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Sample records for curema valenciennes teleostei

  1. Gyrodactylus salinae n. sp. (Platyhelminthes: Monogenea) infecting the south European toothcarp Aphanius fasciatus (Valenciennes) (Teleostei, Cyprinodontidae) from a hypersaline environment in Italy

    PubMed Central

    2011-01-01

    Background Historically, non-native species of Gambusia (Poeciliidae) have been used to control larval stages of the Asian tiger mosquito, Stegomyia albopicta Reinert, Harbach et Kitching, 2004 throughout Italy. The potential utility of indigenous populations of Aphanius fasciatus (Valenciennes) (Teleostei: Cyprinodontidae) as an appropriate alternative biological control is currently being explored. A sub-sample of ten fish collected from Cervia Saline, Italy (salinity 65 ppt; 30°C) to assess their reproductive capability in captivity, harboured a moderate infection of Gyrodactylus von Nordmann, 1832 (Platyhelminthes, Monogenea). A subsequent morphological and molecular study identified this as being a new species. Results Gyrodactylus salinae n. sp. is described from the skin, fins and gills of A. fasciatus. Light and scanning electron microscopical (SEM) examination of the opisthaptoral armature and their comparison with all other recorded species suggested morphological similarities to Gyrodactylus rugiensoides Huyse et Volckaert, 2002 from Pomatoschistus minutus (Pallas). Features of the ventral bar, however, permit its discrimination from G. rugiensoides. Sequencing of the nuclear ribosomal DNA internal transcribed spacers 1 and 2 and the 5.8S rRNA gene and a comparison with all species listed in GenBank confirmed they are unique and represent a new species (most similar to Gyrodactylus anguillae Ergens, 1960, 8.3% pair-wise distance based on 5.8S+ITS2). This represents the first species of Gyrodactylus to be described from Aphanius and, to date, has the longest ITS1 (774 bp) sequenced from any Gyrodactylus. Additional sampling of Cervia Saline throughout the year, found G. salinae n. sp. to persist in conditions ranging from 35 ppt and 5°C in December to 65 ppt and 30°C in July, while in captivity a low level of infection was present, even in freshwater conditions (0 ppt). Conclusions The ability of G. salinae n. sp. to tolerate a wide range of salinities

  2. Ligophorus spp. (Monogenoidea: Dactylogyridae) parasitizing mullets (Teleostei: Mugiliformes: Mugilidae) occurring in the fresh and brackish waters of the Shatt Al-Arab River and Estuary in southern Iraq, with the description of Ligophorus sagmarius sp. n. from the greenback mullet Chelon subviridis (Valenciennes).

    PubMed

    Kritsky, Delane C; Khamees, Najim R; Ali, Atheer H

    2013-12-01

    The gills of three of five species of mullets (Teleostei: Mugiliformes: Mugilidae) collected from the brackish and fresh waters of southern Iraq were infected with species of Ligophorus (Monogenoidea: Dactylogyridae) as follows: greenback mullet Chelon subviridis (Valenciennes) infected with Ligophorus lebedevi Dmitrieva, Gerasev, Gibson, Pronkina and Galli, 2012, Ligophorus bantingensis Soo and Lim, 2012, Ligophorus sagmarius n. sp., and Ligophorus fluviatilis (Bychowsky, 1949) Dmitrieva, Gerasev, Gibson, Pronkina, and Galli, 2012; Klunzinger’s mullet Liza klunzingeri (Day) with L. bantingensis, L. fluviatilis, and an apparently undescribed species of Ligophorus; and abu mullet Liza abu (Heckel) with L. bantingensis and L. fluviatilis. The keeled mullet Liza carinata (Valenciennes) and Speigler’s mullet Valamugil speigleri (Bleeker) were uninfected. L. sagmarius n. sp. is described, and L. lebedevi and L. bantingensis are redescribed. Available specimens of L. fluviatilis and the undescribed species of Ligophorus from Klunzinger’s mullet were insufficient for description.

  3. First record of Mugil hospes in the Gulf of Mexico and its identification from Mugil curema using ctenii.

    PubMed

    Ibáñez, A L; González-Castro, M; Pacheco-Almanzar, E

    2011-01-01

    This study gives the first record of Mugil hospes distributed in the Gulf of Mexico. This species previously has been confused with its congener Mugil curema and can be easily differentiated by the shape of the ctenii on their scales.

  4. Surface ultrastructure of the gills of the mullets Mugil curema, M. liza and M. platanus (Mugilidae, Pisces).

    PubMed

    Eiras-Stofella, D R; Charvet-Almeida, P; Fanta, E; Vianna, A C

    2001-02-01

    Mugil curema, M. liza, and M. platanus were collected from the southeastern and southern coast of Brazil. The second gill arches were analyzed by scanning electron microscopy and histology. The highest density of chloride and mucus-secreting cells was observed in the gill filaments of M. liza and M. platanus. Spines are scarce and were found only in the pharyngeal region of M. curema. The dorsal angle of curvature of the simple projections is most reduced in the rakers of M. liza and M. platanus. The raker borderline on the internal side of the arches of M. curema has grooves that do not occur in the other two species. On the external side of the branchial arches, the borders of the rakers of M. liza and M. platanus are smooth. The shape of the rakers is characteristic for each species: in M. curema, it resembles the letter "D"; in M. liza, it is trapezoidal, and in M. platanus, it is triangular. Thus there is a morphologic similarity between M. liza and M. platanus, and both differ from M. curema. All three species show elongated and extremely elaborated rakers that are placed next to each other and turned toward the opercular cavity. There are few taste buds and only several mucus-secreting cells along the whole pharyngeal region. These characteristics suggest that these species do not select food chemically but obtain it mechanically with the rakers and aggregate it with mucus.

  5. The complete mitochondrial genome of the rocky reef fish Cheilodactylus variegatus Valenciennes, 1833 (Teleostei: Cheilodactylidae).

    PubMed

    Quezada-Romegialli, Claudio; Véliz, David; Docmac, Felipe; Harrod, Chris

    2016-07-01

    Cheilodactylus variegatus is a common benthivorous marine fish inhabiting in rocky subtidal habitats in the eastern south Pacific coast of Chile and Peru. However, its biology and ecology are relatively understudied and its taxonomic assignment has been debated recently. The complete mitochondrial genome was assembled de novo and mapped to a reference using 5.97 million of reads obtained through Ion Torrent next generation sequencing, resulting in a circular sequence of 16,652 bp in length. Gene composition and arrangement comprised to that reported for most fishes and contained the typical structure of 2 rRNAs, 13 protein-coding genes, 22 tRNAs and 1 non-coding region. This mitogenome provides a valuable resource for studies of fish molecular systematics, phylogeography and population genetics.

  6. The white mullet (Mugil curema) as biological indicator to assess environmental stress in tropical coastal lagoons.

    PubMed

    García-Gasca, Alejandra; Ríos-Sicairos, Julián; Hernández-Cornejo, Rubí; Cunha, Isabel; Gutiérrez, Jesús N; Plascencia-González, Héctor; de la Parra, Luz María García; Abad-Rosales, Selene; Betancourt-Lozano, Miguel

    2016-12-01

    Several coastal lagoons and estuaries in Mexico receive untreated domestic and industrial discharges which contain complex mixtures of contaminants. In order to assess the effects of chemical contamination, we used the White mullet (Mugil curema) as biological indicator. We worked in two estuaries located in Northwest Mexico: Urias (highly polluted) and Teacapan (less polluted, therefore used as reference site). We measured several endpoints at different levels of biological organization: vitellogenin transcription in males as biomarker of estrogenic contamination, as well as reproductive, morphological (deformities), morphometric, and meristic parameters. Total RNA was isolated from the liver, and a partial sequence of the mullet vitellogenin gene was obtained; gene expression was analyzed by quantitative PCR. At the same time, gonad samples were analyzed by histologic techniques to determine sex ratios and the reproductive cycle stage. The reproductive season was detected from February to June in both sites, but the gonadosomatic index was consistently higher in Teacapan. Sex ratios were female-biased in both estuaries, and one intersex gonad and several malformations were found in fish from Urias. Vitellogenin gene transcription in males was detected in both sites, although gene expression was slightly higher in Urias. The results obtained in this study indicate that biological effects of contamination are evident in fish, environmental estrogens may be present in both estuaries, and the white mullet is useful as biological indicator to identify and characterize environmental stressors in tropical coastal ecosystems.

  7. Grammoplites vittatus (Valenciennes), (Scorpaeniformes, Platycephalidae), removed from synonymy with Grammoplites scaber (Linnaeus).

    PubMed

    Knapp, Leslie W; Imamura, Hisashi

    2014-08-04

    Grammoplites vittatus (Valenciennes), often previously overlooked by authors or regarded as a junior synonym of G. scaber (Linnaeus), is shown here to be a valid species.  It has more gill rakers (7-8) then G. scaber and G. knappi (usually 6) and a narrower interorbital width than G. scaber.  A key to the species of Grammoplites Fowler is  given. 

  8. Is otolith microchemistry (Sr: Ca and Ba:Ca ratios) useful to identify Mugil curema populations in the southeastern Caribbean Sea?

    PubMed

    Avigliano, E; Callicó-Fortunato, R; Buitrago, J; Volpedo, A V

    2015-11-01

    The aim of the present study was to evaluate the potential use of otolith microchemistry (Sr:Ca and Ba:Ca ratios) to identify silver mullet, Mugil curema, populations in Southeastern Caribbean Sea. Fish samples were collected in 7 areas of Nueva Esparta State (Venezuela). The otolith Sr:Ca and Ba:Ca ratios and water Sr:Ca were determined (by ICP-OES and EDTA volumetric method). Otoliths Sr:Ca and Ba:Ca ratios and Sr:Ca partition coefficient of mullets in Cubagua island (south of the State) were significantly different from ratios in La Guardia (north of the State). A discriminant analysis of otolith Sr:Ca and Ba:Ca ratios separated Cubagua Island from La Guardia values. These results suggest the existence of different mullet groups in the Southeastern Caribbean Sea. For this, the simultaneous use of Sr:Ca and Ba:Ca ratios could be a potential tool to identify populations in the study area.

  9. Ultrastructural study of spermiogenesis and the spermatozoon of Cavisoma magnum (Southwell, 1927) (Acanthocephala, Palaeacanthocephala, Cavisomidae), from Siganus lineatus (Pisces, Teleostei, Siganidae) (Valenciennes, 1835) in New Caledonia.

    PubMed

    Foata, J; Quilichini, Y; Justine, J-L; Bray, R A; Marchand, B

    2012-02-01

    This paper presents an ultrastructural study of Cavisoma magnum (Acanthocephala, Cavisomatidae) with a Transmission Electron Microscopy tool. This parasite of the fish Siganus lineatus is here reported for the first time from off New Caledonia, South Pacific. It is the first study describing the ultrastructure, spermiogenesis and spermatozoon of a species of the family Cavisomatidae. The young spermatid of C. magnum possesses a centriole constituted of doublets without a central element. After the elaboration of a flagellum of 9+2 pattern, the centriole migrates in a nuclear groove. Then the flagellum migration occurs and gives rise to a spermatozoon. The distribution and the size of the protein granules are reported and the posterior extremity appears like a chromatin lamina wave. Comparative ultrastructural data are presented on sperm and spermiogenesis of the Acanthocephala and Rotifers examined to date and the phylogenetic implications are discussed.

  10. Persistence of external signs in Pacific herring Clupea pallasii Valenciennes with ichthyophoniasis

    USGS Publications Warehouse

    Hart, Lucas M.; Conway, Carla M.; Elliott, Diane G.; Hershberger, Paul K.

    2016-01-01

    The progression of external signs of Ichthyophonus infection in Pacific herring Clupea pallasii Valenciennes was highly variable and asynchronous after intraperitoneal injection with pure parasite preparations; however, external signs generally persisted through the end of the study (429 days post-exposure). Observed signs included papules, erosions and ulcers. The prevalence of external signs plateaued 35 days post-exposure and persisted in 73–79% of exposed individuals through the end of the first experiment (147 days post-exposure). Among a second group of infected herring, external signs completely resolved in only 10% of the fish after 429 days. The onset of mortality preceded the appearance of external signs. Histological examination of infected skin and skeletal muscle tissues indicated an apparent affinity of the parasite for host red muscle. Host responses consisted primarily of granulomatous inflammation, fibrosis and necrosis in the skeletal muscle and other tissues. The persistence and asynchrony of external signs and host response indicated that they were neither a precursor to host mortality nor did they provide reliable metrics for hindcasting on the date of exposure. However, the long-term persistence of clinical signs in Pacific herring may be useful in ascertaining the population-level impacts of ichthyophoniasis in regularly observed populations.

  11. Henneguya mauritaniensis n. sp. (Myxozoa) from the arterial bulb of Pagrus caeruleostictus (Valenciennes, 1830) off Mauritania.

    PubMed

    Khlifa, Sidi; Miller, Terrence L; Adlard, Robert D; Faye, N'gor; Sasal, Pierre

    2012-09-01

    We describe a new species of myxozoan, Henneguya mauritaniensis n. sp., extracted from the arterial bulb of the bluespotted seabream, Pagrus caeruleostictus (Valenciennes, 1830), collected in Mauritanian waters. Out of the 209 individuals examined, 30.1 % were infected with this new taxon. Spore total length ranged from 15.0 to 20.5 μm with a mean of 17.9 μm. The two polar capsules were equal in size, and pyriform and caudal appendages joined until mid-length. Morphometric analysis revealed significant differences between H. mauritaniensis n. sp. and morphologically similar species from this region as well as congeners known from other sparid hosts. Phylogenetic analysis of 18 S rDNA indicated that this new species is closely related to Henneguya pagri, reported recently from Pagrus major off Japan. Bayesian inference and maximum likelihood analyses of the 18 S rDNA dataset also revealed that species of marine Henneguya reported forming pseudocysts in the hearts of their fish hosts were closely related. Histological analysis of the H. mauritaniensis n. sp. pseudocysts embedded in the arterial bulb of P. caeruleostictus suggests that these parasites may cause considerable pathology, which may impact negatively on the health of the fish host. Finally, we discussed the importance of a combination of morphological and molecular analysis for species description because of high variability in size within the same taxa.

  12. Length-weight relationship and condition factor of Liza subviridis (Valenciennes, 1836) of Parangipettai waters, southeast coast of India.

    PubMed

    Ashiq Ur Rahman, M; Khan, S Ajmal; Lyla, P S; Kadharsha, K; Chander, P Mohan; John, B Akbar

    2013-04-01

    Determination of Length-weight Relationship (LWR) of any commercially important fish is crucial to validate the wild stock level, to predict their wellbeing in the natural habitat and for various sustainable fishery management practices. Liza subviridis (Valenciennes) is noted to be highly abundant along the coast of Parangipettai, South east coast of India. Hence, the present study was aimed to establish Length-weight relationship and condition factor of Greenback mullet, Liza subviridis (Valenciennes) occurring in Vellar estuary, Parangipettai (lat. 11 degrees 30' N, long. 79 degrees 46' E) using least square method. To determine the actual relationship between length and weight of L. subviridis exponent coefficient or equilibrium constant (b) and relative condition factor (Kn) analysis were adopted. The females were found to be heavier than males at similar length. The equilibrium constant 'b' was found to be 2.7106 in males and 2.8927 in females. The corresponding parabolic representation for male was W = 0.0462L(2.7106) and for female W = 0.0382L(2.8927). The equilibrium constant did not obey the cube law as it deviated significantly from 3 in the case of males. The relative condition factor around 1 and little over it revealed the well-being of L. subviridis in Parangipettai waters.

  13. Molecular Phylogeny and Biogeography of Percocypris (Cyprinidae, Teleostei)

    PubMed Central

    Wang, Mo; Yang, Jun-Xing; Chen, Xiao-Yong

    2013-01-01

    Fierce predatory freshwater fishes, the species of Percocypris (Cyprinidae, Teleostei) inhabit large rivers or lakes, and have a specific distribution pattern. Only a single species or subspecies occurs in each large-scale drainage basin of the Southeastern Tibetan Plateau. In this study, the molecular phylogenetic relationships for all but one of the described subspecies/species of Percocypris were investigated based on three mitochondrial genes (16S; COI; Cyt b) and one nuclear marker (Rag2). The results of Maximum Likelihood and Bayesian Inference analyses show that Percocypris is a strongly supported monophyletic group and that it is the sister group of Schizothorax. Combined with analyses of morphological characters, our results suggest that Percocypris needs to be reclassified, and we propose that six species be recognized, with corresponding distributions in five main drainages (including one lake). In addition, based on the results of the estimation of divergence times and ancestral drainages, we hypothesize that Percocypris likely originated in the early Miocene from a paleo-connected drainage system containing the contemporary main drainages of the Southeastern Tibetan Plateau. This study suggests that vicariance (due to the uplift of the Tibetan Plateau modifying the large-scale morphologies of drainage basins in the Southeastern Tibetan Plateau) has played an important role in the speciation of the genus. Furthermore, external morphological characters (such as the length of the fins) and an internal trait (the position of pterygiophore) appear to be correlated with different habitats in rivers and the lake. PMID:23750199

  14. Microcotyle omanae n. sp. (Monogenea: Microcotylidae), a parasite of Cheimerius nufar (Valenciennes) (Sparidae) from the Arabian Sea.

    PubMed

    Machkewskyi, Volodymyr K; Dmitrieva, Evgenija V; Al-Jufaili, Sara; Al-Mazrooei, Nashwa A M

    2013-10-01

    Microcotyle omanae n. sp. (Monogenea: Microcotylidae) is described from the gills of Cheimerius nufar (Valenciennes) (Sparidae) from the Arabian Sea. The new species closely resembles Microcotyle arripis Sandars, 1945, M. helotes Sandars, 1944, M. caudata Goto, 1984 and M. sebastis Goto, 1984, which have also been found in the Indo-Pacific. Microcotyle omanae n. sp. differs from M. arripis, M. helotes and M. caudata by its greater number of testes, from M. arripis, M. helotes by its greater length of the genital atrium, length/width ratio of the genital atrium and length of the eggs, and from M. helotes also in greater width of the clamps, from M. caudata and M. sebastis in its greater number of clamps and additionally from M. sebastis by its smaller genital atrial spines and clamps and by the ratio between length and width of the genital atrium. Moreover, the mature specimens of the new species have greater average body length than all above mentioned species. Correlations between 15 morphometric characters and body length are analysed in the new species, and their significance for species differentiation is discussed.

  15. Comparative analysis of Rapana venosa (Valenciennes, 1846) from different biotopes of the Black Sea based on its morphological characteristics

    NASA Astrophysics Data System (ADS)

    Kos'yan, A. R.

    2013-02-01

    The Asian whelk Rapana venosa (Valenciennes, 1846) (Gastropoda: Neogastropoda: Muricidae), being tolerant to wide variations in the temperature, salinity, and oxygen concentration, successfully settled down in the Black Sea and eventually became one of the dominant species in the benthic ecosystems. The whelk inhabits all types of grounds all over the Black sea demonstrating a wide spectrum of morphological modifications. The objective of this research is to compare 10 samples of R. venosa from different biotopes of the Black Sea coast from the western Crimea to Sochi. The results of the statistical comparison based on 15 morphological characteristics showed that most of the samples differed from each other with high statistical significance ( p < 0.001). The material fell into five groups on the discriminant analysis diagram corresponding to the biotope in which each was collected. The main ecological factor influencing the morphological variability of the rapa whelk populations is the characteristics of prey items they feed on, i.e., the bivalve species ( Mytilus galloprovincialis, Anadara sp., Chamelea gallina), the prevailing prey size, and its abundance.

  16. A new species of Anchistrotos Brian, 1906 (Copepoda: Cyclopoida: Taeniacanthidae) from the filamentous shrimpgoby Myersina filifer (Valenciennes) (Perciformes: Gobiidae) in Korean waters.

    PubMed

    Moon, Seong Yong; Lee, Jeong-Hoon; Kim, Doo Nam

    2015-10-01

    A new species of Anchistrotos Brian, 1906 (Copepoda: Cyclopoida: Taeniacanthidae), parasitic in the branchial cavities of the filamentous shrimpgoby Myersina filifer (Valenciennes) (Perciformes: Gobiidae) from Korea is described. The new species is most closely related to A. tangi Venmathi Maran, Moon & Adday, 2014, but differs from it by the following combination of characters in the adult female: the U-shaped rostrum, the distal margin of the anal somite lacks patches of spinules, the proximal segment of the maxilliped is without seta, and the maxilliped claw is armed with long and small naked setae. This is the tenth species of the genus and a key is provided to distinguish all nominal species.

  17. Neoechinorhynchus (Neoechinorhynchus) chimalapasensis n. sp. (Acanthocephala: Neoechinorhynchidae) from the freshwater fish Awaous banana (Valenciennes) (Gobiidae) in Mexico.

    PubMed

    Salgado-Maldonado, Guillermo; Caspeta-Mandujano, Juan Manuel; Martínez-Ramírez, Emilio

    2010-03-01

    Neoechinorhynchus (Neoechinorhynchus) chimalapasensis n. sp. (Eoacanthocephala: Neoechinorhynchidae) is described from the intestine of Awaous banana (Valenciennes) (Pisces: Gobiidae) collected in the Río Negro, a tributary in the upper Río Coatzacoalcos basin, Santa María Chimalapa, Oaxaca State, Mexico. It is the third species of Neoechinorhynchus Stiles & Hassall, 1905 described from Mexican freshwater fishes, although 36 other species are known from freshwater fishes in the Americas. Like four other species of Neoechinorhynchus from freshwater fishes in North America and Mexico, N. (N.) limi Muzzall & Buckner, 1982, (N.) rutili (Müller, 1780) Stiles & Hassall, 1905, N. (N.) salmonis Ching, 1984 and N. (N.) roseus Salgado-Maldonado, 1978, males and females of the new species are less than 20 mm in length, lack conspicuous sexual dimorphism in size, have a small proboscis of about 0.1 mm in length with the largest hooks being the anteriormost, about 30-90 microm in length and of equal size, and have subequal lemnisci, larger than the proboscis receptacle but still relatively short and, in males, generally restricted to a position considerably anterior to the testes. The new species is closest to N. (N.) roseus, but it is distinguished from it by having: (1) a slightly larger cylindrical proboscis with almost parallel sides versus a globular proboscis with a rounded tip which is shorter and somewhat wider in N. (N.) roseus; (2) smaller but robust anterior proboscis hooks that do not reach the equatorial level or extend beyond the hooks of the middle circle as in N. (N.) roseus; and (3) the female gonopore situated ventrally subterminal, as opposed to being a significant distance anteriorly to the posterior extremity in N. (N.) roseus.

  18. Morphological aspects and histological effects of the attachment organ of Parabrachiella sp. (Copepoda: Lernaeopodidae) on the grey mullet, Mugil liza Valenciennes.

    PubMed

    Plaul, S E; Montes, M M; Barbeito, C G; Martorelli, S R

    2013-10-01

    The genus Parabrachiella Wilson, 1915 (Lernaeopodidae) is represented by copepods that are highly adapted to a parasitic way of life. In Argentina, only P. insidiosa var. lageniformis Heller, 1865, P. chevreuxii Van Beneden, 1891 and P. spinicephala Ringuelet, 1945 have been cited, but none of these have been reported on mugilids. Recently, other species of this genus were found attached to the nasal cavities of juvenile grey mullets, Mugil liza Valenciennes, from Samborombón bay, Buenos Aires province. In this study, the prevalence and mean intensity of the Parabrachiella sp. on grey mullet is investigated. In addition, the damage the parasite imposes on its hosts is examined through evaluation of histological sections and immunostaining for proliferative cell nuclear antigen (PCNA). The morphology of the parasite's bulla is described from light and scanning electron micrographs.

  19. A cladistic re-analysis of the Gadiformes (Teleostei, Paracanthopterygii) using three-item analysis.

    PubMed

    Grand, Anaïs; Zaragüeta Bagils, Rene; Vélez, Lina María Duque; Vélez, Lina María; Ung, Visotheary

    2014-12-02

    In the present paper, we describe LisBeth, a newly published phylogenetic program. LisBeth implements the cladistic three-item analysis for systematics and biogeography. We show how LisBeth handles character representation, character analysis, exact search functions, reconstruction of the intersection tree and other features, such as retention index, completeness index, character history and link with other programs such as PAUP*, version 4.0b10, TNT and Xper2. Using LisBeth, we reanalyze the phylogeny based on morphological characters of the order Gadiformes (Teleostei, Paracanthopterygii) published by Endo (2002) and compare our results. We also describe the generation of hypotheses of homology following Endo's guidelines versus 3ia representation schemes. We compare the topologies of all results and show the implications of the interpretation of character history.

  20. Relationship between ecomorphology and trophic segregation in four closely related sympatric fish species (Teleostei, Sciaenidae).

    PubMed

    Blasina, Gabriela; Molina, Juan; Lopez Cazorla, Andrea; Díaz de Astarloa, Juan

    This study explores the relationship between ecomorphology and trophic segregation in four closely related sympatric fish species (Teleostei, Sciaenidae) that are known to differ in their trophic habits. Only adult specimens were analyzed: 103 Cynoscion guatucupa, 77 Pogonias cromis, 61 Micropogonias furnieri, and 48 Menticirrhus americanus. The four species presented divergent ecomorphological traits related to swimming agility, prey spotting and capture, and the potential size of prey they were able to swallow. Results suggest that these sciaenid species can partition the food resources, even though they completely overlap in space. Differences in their ecomorphological traits appear to correlate closely with the diet and consequently could explain the trophic differentiation observed. Arguably, these ecomorphological differences play a significant role in the coexistence of the adults of these sympatric fish species.

  1. Effects of temperature and salinity on the development of embryos and larvae of the veined rapa whelk Rapana venosa (Valenciennes, 1846)

    NASA Astrophysics Data System (ADS)

    Ban, Shaojun; Zhang, Tao; Pan, Hengqian; Pan, Yang; Wang, Pingchuan; Xue, Dongxiu

    2014-07-01

    The major population of the veined rapa whelk Rapana venosa (Valenciennes, 1846), which is an important fishery resource, is facing a large decline in China. We studied the effects of incubation temperature (16-34°C at salinity 30) and salinity (5-45 at 25°C) on the incubation period and subsequent larval development. In the temperature experiment, the shortest incubation period was 12 days at 34°C, the lower temperature limit was 16°C, the longest mean shell length (1 193±17 μm) occurred at 25°C and the highest survival rate 72.28%±5.62% was observed at 28°C. In the salinity experiment, the shortest incubation period was 15 days at 25. The salinity tolerance range was 15-40, the longest mean shell length (855±9 μm) and the highest survival rate 72.93%±4.85% were both observed at 35. This study demonstrated that, during the egg-mass stage, temperature and salinity regimes influence later growth and survival of larvae. These observations deepen our understanding of the ecology and conservation of natural populations of Rapana venosa.

  2. Genus-level taxonomic changes implied by the mitochondrial phylogeny of grey mullets (Teleostei: Mugilidae).

    PubMed

    Durand, Jean-Dominique; Chen, Wei-Jen; Shen, Kang-Ning; Fu, Cuizhang; Borsa, Philippe

    2012-01-01

    , Osteomugil))]. Agonostomus monticola and several species with large distribution ranges (including Moolgarda seheli, Mugil cephalus and M. curema) consist of separate lineages whose geographic distribution suggests they are cryptic species, thus warranting further taxonomic work in the Mugilidae at the infra-generic level.

  3. Description of two new Bathyaethiops species (Teleostei: Alestidae) from the Congo basin.

    PubMed

    Moritz, Timo; Schliewen, Ulrich K

    2016-06-02

    Two new species of Bathyaethiops (Teleostei: Characiformes: Alestidae) are described. Bathyaethiops baka n. sp. is a dwarf species with the largest known specimen being only 24.4 mm SL. The species is characterized by an incomplete squamation and a large humeral spot. Bathyaethiops baka n. sp. is known so far only from the Ngoko River of Southeastern Cameroon, a tributary of the Sangha River in the northern Congo basin. The second species, Bathyaethiops flammeus n. sp., shows a diagnostic spot in front of the dorsal-fin base, which is devoid of melanophores and bright red in life. The species is described from the Bakéré River at Yambula-Bakéré, a locality north-west of Kisangani in the Central Congo basin. Other records of Bathyaethiops flammeus n. sp. from the Tshuapa respectively Ruki River at Boende and Eala, Central Congo basin, suggests a wider geographic distribution. A key to all species of Bathyaethiops is provided.

  4. Karyotype diversity and patterns of chromosomal evolution in Eigenmannia (Teleostei, Gymnotiformes, Sternopygidae)

    PubMed Central

    Sene, Viviani França; Pansonato-Alves, José Carlos; Utsunomia, Ricardo; Oliveira, Claudio; Foresti, Fausto

    2014-01-01

    Abstract Conventional (Giemsa, C-banding, Ag – NORs) and molecular [5S rDNA, 18S rDNA, (TTAGGG)n] cytogenetic techniques were employed to study six species of the genus Eigenmannia Jordan & Evermann, 1896. They exhibited diploid chromosome numbers ranging from 2n=28 (Eigenmannia sp.1) to 2n=38 (Eigenmannia virescens (Valenciennes, 1836)). The C-banding results revealed that species with the lowest 2n have less heterochromatin content and that morphologically differentiated sex chromosomes observed in two species showed distinct patterns of heterochromatin. While the X1, X2 and Y-chromosomes of Eigenmannia sp.2 showed only centromeric heterochromatin, the XY sex chromosomes of Eigenmannia virescens possessed large heterochromatic blocks in the terminal position, particularly on the X chromosome. The nucleolus organizer regions (NORs) were located in different positions when compared to the 5S rDNA sites. Additionally, the presence of minor ribosomal gene sites on the sex chromosome pair of Eigenmannia virescens represented a new type of the sex chromosomes in this group. The telomeric probe (TTAGGG)n hybridized to the terminal portion of all chromosomes in all species examined however, interstitial telomeric sites were found in the metacentric pair No. 2 in Eigenmannia sp.1. The analyzes confirmed some hypotheses about karyotype evolution in the genus Eigenmannia, and brought new information about the distribution of the genetic material in the chromosomes of the samples analyzed providing new insights for understanding the process differentiation in the genomes of species under study. PMID:25610544

  5. Un nouveau genre d'Aipichthyoidea (Teleostei, Acanthomorpha) du Cénomanien inférieur marin de Hgula (Liban): description et relations phylogénétiques

    NASA Astrophysics Data System (ADS)

    Otero, Olga

    1997-09-01

    Freigichthys elleipsis nov. gen., nov. sp., from the Lower Cenomanian of Hgula (Lebanon) is described. Its phylogenetic relationships within the Aipichthyoidea (Teleostei, Ctenosquamata) are established. It is the plesiomorphic member of this superfamily that includes the genera Aipichthys Steindachner, 1860, ParaipichthysGaudant, 1978and Aipichthyoides Gayet 1980.

  6. The importance of gobies (Gobiidae, Teleostei) as hosts and transmitters of parasites in the SW Baltic

    NASA Astrophysics Data System (ADS)

    Zander, C. D.; Strohbach, U.; Groenewold, S.

    1993-02-01

    The parasite fauna of five goby species (Gobiidae, Teleostei) was investigated in the Baltic Sea during the period 1987 to 1990. 13 parasite species were found in samples from the Lübeck Bight: Bothriocephalus scorpii, Schistocephalus sp. (Cestoda); Cryptocotyle concavum, Cryptocotyle lingua, Podocotyle atomon, Derogenes varicus (Digenea); Hysterothylacium sp. (cf. auctum), Contracaecum sp., Anisakis simplex (Nematoda); Corynosoma sp., Echinorhynchus gadi, Neoechinorhynchus rutili, Pomphorhynchus laevis (Acanthocephala). The number of parasite species were: 10 in the sand goby Pomatoschistus minutus, 8 in the black goby Gobius niger, 7 in the two-spotted goby Gobiusculus flavescens, 6 in the common goby Pomatoschistus microps, and 5 in the painted goby Pomatoschistus pictus. Neoechinorhynchus rutili occurred only in P. minutus, and Corynosoma sp. only in G. niger. The extent to which the gobies were parasitized clearly depended on the respective ways of life and, moreover, on the kind of prey ingested by the hosts. Additionally, the age of the hosts might be important. The highest rate of parasitism, more than 60%, was reached by Hysterothylacium sp. in G. niger and by Cryptocotyle concavum in P. microps. Infestation incidence lay mostly below 40% which means a satellite species status (Holmes, 1991). The number of parasite species was highest in summer; the highest intensities of single parasites occurred in spring ( Podocotyle atomon) or autumn ( Crytocotyle concavum). Bothriocephalus scorpii, Hysterothylacium sp. and Podocotyle infested their juvenile hosts very early, but only Hysterothylacium was accumulated by G. niger during its whole life span, whereas Bothriocephalus persisted also in older gobies in low intensities. The cercariae of Cryptocotyle spp. penetrate actively into their hosts; all the other parasites named were transmitted in larval form by prey organisms which consisted mainly of planktonic and benthic crustaceans. The gobies were final hosts

  7. Ultrastructure of the spermatozoon of the digenean Tergestia acanthocephala (Stossich, 1887) (Gymnophalloidea: Fellodistomidae): An intestinal parasite of Belone belone gracilis (Pisces: Teleostei).

    PubMed

    Kacem, H; Ndiaye, P I; Neifar, L; Torres, J; Miquel, J

    2015-06-01

    The ultrastructural organization of the spermatozoon of the digenean Tergestia acanthocephala (Gymnophalloidea: Fellodistomidae) is described. Live digeneans were collected from Belone belone gracilis (Teleostei: Belonidae), caught off the Gulf of Gabès in Chebba (Tunisia). The mature spermatozoon of T. acanthocephala exhibits the general pattern described in numerous digeneans, characterized by the presence of two axonemes of the different length of the 9+'1' pattern of the Trepaxonemata, a nucleus, two mitochondria, two bundles of parallel cortical microtubules, external ornamentation, spine-like bodies and granules of glycogen. Moreover, the morphology of the posterior spermatozoon extremity in T. acanthocephala corresponds to the fasciolidean type of Quilichini et al. (2010a).

  8. From sneaker to parental male: change of reproductive traits in the black goby, Gobius niger (Teleostei, Gobiidae).

    PubMed

    Immler, Simone; Mazzoldi, Carlotta; Rasotto, Maria Berica

    2004-02-01

    This study focuses on the consequences of the switch of tactic from parasitic to parental male in the black goby, Gobius niger (Teleostei: Gobiidae), a species showing two alternative male mating tactics. Older and larger males defend nests, court, and perform parental care on eggs, while younger and smaller ones behave as parasites, sneaking into nests while spawning occurs. Males adopting different tactics are known to present differences in primary and secondary sex traits. The social context of sneaker males was manipulated to induce a tactic switch. Sneakers were kept under two different experimental treatments with or without a female, and under exclusion of male-male competition. Males changed tactics, courting females, spawning, and performing parental care. All males showed substantial changes in primary sexual traits, such as a reduction in gonadal development and an increase in the investment in accessory structures. The experimental groups differed in the functionality of gonads and accessory organs and in the development of the secondary sex traits. These results demonstrate that the moment of switching is not genetically fixed in the black goby. Sneaker males are able to quickly reallocate energy in primary and secondary sex traits, in accordance with the adopted tactic. Several aspects of this flexible reproductive pattern resemble the socially controlled sex change found in sequential hermaphrodites.

  9. Evolution of microhabitat association and morphology in a diverse group of cryptobenthic coral reef fishes (Teleostei: Gobiidae: Eviota).

    PubMed

    Tornabene, Luke; Ahmadia, Gabby N; Berumen, Michael L; Smith, Dave J; Jompa, Jamaluddin; Pezold, Frank

    2013-01-01

    Gobies (Teleostei: Gobiidae) are an extremely diverse and widely distributed group and are the second most species rich family of vertebrates. Ecological drivers are key to the evolutionary success of the Gobiidae. However, ecological and phylogenetic data are lacking for many diverse genera of gobies. Our study investigated the evolution of microhabitat association across the phylogeny of 18 species of dwarfgobies (genus Eviota), an abundant and diverse group of coral reef fishes. In addition, we also explore the evolution of pectoral fin-ray branching and sensory head pores to determine the relationship between morphological evolution and microhabitat shifts. Our results demonstrate that Eviota species switched multiple times from a facultative hard-coral association to inhabiting rubble or mixed sand/rubble habitat. We found no obvious relationship between microhabitat shifts and changes in pectoral fin-ray branching or reduction in sensory pores, with the latter character being highly homoplasious throughout the genus. The relative flexibility in coral-association in Eviota combined with the ability to move into non-coral habitats suggests a genetic capacity for ecological release in contrast to the strict obligate coral-dwelling relationship commonly observed in closely related coral gobies, thus promoting co-existence through fine scale niche partitioning. The variation in microhabitat association may facilitate opportunistic ecological speciation, and species persistence in the face of environmental change. This increased speciation opportunity, in concert with a high resilience to extinction, may explain the exceptionally high diversity seen in Eviota compared to related genera in the family.

  10. The mitochondrial genome of spotted green pufferfish Tetraodon nigroviridis (Teleostei: Tetraodontiformes) and divergence time estimation among model organisms in fishes.

    PubMed

    Yamanoue, Yusuke; Miya, Masaki; Inoue, Jun G; Matsuura, Keiichi; Nishida, Mutsumi

    2006-02-01

    We determined the whole mitochondrial genome sequence for spotted green pufferfish, Tetraodon nigroviridis (Teleostei: Tetraodontiformes). The genome (16,488 bp) contained 37 genes (two ribosomal RNA genes, 22 transfer RNA genes, and 13 protein-coding genes) plus control region as found in other vertebrates, with the gene order identical to that of typical vertebrates. The sequence was used to estimate phylogenetic relationships and divergence times among major lineages of fishes, including representative model organisms in fishes. We employed partitioned Bayesian approaches for these two analyses using two datasets that comprised concatenated amino acid sequences from 12 protein-coding genes (excluding the ND6 gene) and concatenated nucleotide sequences from the 12 protein-coding genes (without 3rd codon positions), 22 transfer RNA genes, and two ribosomal RNA genes. The resultant trees from the two datasets were well resolved and largely congruent with those from previous studies, with spotted green pufferfish being placed in a reasonable phylogenetic position. The approximate divergence times between spotted green pufferfish and model organisms in fishes were 85 million years ago (MYA) vs. torafugu, 183 MYA vs. three-spined stickleback, 191 MYA vs. medaka, and 324 MYA vs. zebrafish, all of which were about twice as old as the divergence times estimated by their earliest occurrences in fossil records.

  11. Phylogeny and biogeography of highly diverged freshwater fish species (Leuciscinae, Cyprinidae, Teleostei) inferred from mitochondrial genome analysis.

    PubMed

    Imoto, Junichi M; Saitoh, Kenji; Sasaki, Takeshi; Yonezawa, Takahiro; Adachi, Jun; Kartavtsev, Yuri P; Miya, Masaki; Nishida, Mutsumi; Hanzawa, Naoto

    2013-02-10

    The distribution of freshwater taxa is a good biogeographic model to study pattern and process of vicariance and dispersal. The subfamily Leuciscinae (Cyprinidae, Teleostei) consists of many species distributed widely in Eurasia and North America. Leuciscinae have been divided into two phyletic groups, leuciscin and phoxinin. The phylogenetic relationships between major clades within the subfamily are poorly understood, largely because of the overwhelming diversity of the group. The origin of the Far Eastern phoxinin is an interesting question regarding the evolutionary history of Leuciscinae. Here we present phylogenetic analysis of 31 species of Leuciscinae and outgroups based on complete mitochondrial genome sequences to clarify the phylogenetic relationships and to infer the evolutionary history of the subfamily. Phylogenetic analysis suggests that the Far Eastern phoxinin species comprised the monophyletic clades Tribolodon, Pseudaspius, Oreoleuciscus and Far Eastern Phoxinus. The Far Eastern phoxinin clade was independent of other Leuciscinae lineages and was closer to North American phoxinins than European leuciscins. All of our analysis also suggested that leuciscins and phoxinins each constituted monophyletic groups. Divergence time estimation suggested that Leuciscinae species diverged from outgroups such as Tincinae to be 83.3 million years ago (Mya) in the Late Cretaceous and leuciscin and phoxinin shared a common ancestor 70.7 Mya. Radiation of Leuciscinae lineages occurred during the Late Cretaceous to Paleocene. This period also witnessed the radiation of tetrapods. Reconstruction of ancestral areas indicates Leuciscinae species originated within Europe. Leuciscin species evolved in Europe and the ancestor of phoxinin was distributed in North America. The Far Eastern phoxinins would have dispersed from North America to Far East across the Beringia land bridge. The present study suggests important roles for the continental rearrangements during the

  12. Lamellodiscus aff. euzeti Diamanka, Boudaya, Toguebaye & Pariselle, 2011 (Monogenea: Diplectanidae) from the gills of Cheimerius nufar (Valenciennes) (Pisces: Sparidae) collected in the Arabian Sea, with comments on the distribution, specificity and historical biogeography of Lamellodiscus spp.

    PubMed

    Machkewskyi, Volodymyr K; Dmitrieva, Evgenija V; Gibson, David I; Al-Jufaili, Sara

    2014-11-01

    Specimens of Lamellodiscus Johnston & Tiegs, 1922 (Monogenea: Diplectanidae) were collected from the gills of Cheimerius nufar (Valenciennes) (Sparidae) in the Arabian Sea. All of these parasites belonged to one and the same species, which is morphologically very close to L. euzeti Diamanka, Boudaya, Toguebaye & Pariselle, 2011. A different host, distant locality and small morphological differences compared with the original description of L. euzeti acted as a stimulus for a detailed redescription. The specimens from the Arabian Sea differ slightly in the details of the male copulatory organ (MCO) from the type-specimens of L. euzeti, which were re-examined, and from the respective drawings in its original description. Such differences include a longer inner process of the large element of the accessory piece associated with the proximal part of the copulatory tube, a longer point on the small element of the accessory piece associated with the distal part of the copulatory tube, and the presence of a smooth or slightly folded inner margin of this element rather than structures resembling spines which occur in the type-specimens of L. euzeti. Therefore, the present specimens infecting C. nufar in the Indo-Pacific may represent a different, but morphologically very similar species to the Atlantic form L. euzeti; consequently, they are recognised here as Lamellodiscus aff. euzeti. This form belongs to the 'ignoratus s. str.' subgroup of the genus. The composition of this subgroup is redefined to comprise 17 species, including L. corallinus Paperna, 1965 but excluding L. acanthopagri Roubal, 1981, and the morphology of the MCO of representatives of this group is clarified. A link between the diversity of Lamellodiscus species and the ancestral origin of present-day sparid species in the Tethys Sea is suggested. It is shown that Lamellodiscus spp. exhibit rather high levels of specificity to their hosts, since half of them parasitise only a single host species and c.90

  13. New records of lampriform fishes (Teleostei: Lampriformes) from the Pacific coast of lower Central America, with comments on the diversity, taxonomy and distribution of the Lampriformes in the eastern Pacific Ocean.

    PubMed

    Angulo, Arturo; López-Sánchez, Myrna I

    2017-02-23

    New records of occurrence for four species of lampriform fishes (Teleostei: Lampriformes; Desmodema polystictum, Regalecus russelii, Trachipterus fukuzakii and Zu cristatus) poorly known or previously unknown for the Pacific coast of lower Central America (Costa Rica-Panama) are herein reported. Museum specimens supporting such records are characterized and described. Comparative morphometric and meristic data on other collections and species of lampriforms, as well as distributional information, are provided and discussed. Diversity, taxonomy and distribution of the eastern Pacific species of the order also are briefly discussed. Finally, a key to the eastern Pacific species of the Lampriformes, based on our research and data available in the literature, is presented.

  14. Taxonomic review of the species of Mugil (Teleostei: Perciformes: Mugilidae) from the Atlantic South Caribbean and South America, with integration of morphological, cytogenetic and molecular data.

    PubMed

    Menezes, Naércio A; Nirchio, Mauro; De Oliveira, Cláudio; Siccharamirez, Raquel

    2015-01-10

    Analysis of morphological, molecular and cytological data helped to define and more precisely characterize the species of Mugil from the Atlantic coasts of South Caribbean and South America, allowing a correction of prior misidentifications and distributional ranges. A new species from Venezuela is described and all the species from the area are redescribed. It is demonstrated that the apparent similarity in morphological traits, which contradicted the results from recent molecular studies, is the result of the misuse of traditional morphological characters, and thus both the molecular and cytological data instead are congruent with the morphological differences that are found among mullet species. The presence of Mugil hospes Jordan & Culver in the western south Atlantic is refuted based on the comparison of type material of this species with specimens from this area that also indicated a very significant morphological difference, what on the other hand justifies the recognition of these specimens as Mugil brevirostris (Ribeiro). The distribution of Mugil incilis Hancock is restricted and the similarities among the species formerly depicted in a prior dendrogram is modified following the inclusion of recently obtained molecular data for Mugil curvidens Valenciennes.

  15. Diversification of substrate specificities in teleostei Fads2: characterization of Δ4 and Δ6Δ5 desaturases of Chirostoma estor[S

    PubMed Central

    Fonseca-Madrigal, Jorge; Navarro, Juan C.; Hontoria, Francisco; Tocher, Douglas R.; Martínez-Palacios, Carlos A.; Monroig, Óscar

    2014-01-01

    Currently existing data show that the capability for long-chain PUFA (LC-PUFA) biosynthesis in teleost fish is more diverse than in other vertebrates. Such diversity has been primarily linked to the subfunctionalization that teleostei fatty acyl desaturase (Fads)2 desaturases have undergone during evolution. We previously showed that Chirostoma estor, one of the few representatives of freshwater atherinopsids, had the ability for LC-PUFA biosynthesis from C18 PUFA precursors, in agreement with this species having unusually high contents of DHA. The particular ancestry and pattern of LC-PUFA biosynthesis activity of C. estor make this species an excellent model for study to gain further insight into LC-PUFA biosynthetic abilities among teleosts. The present study aimed to characterize cDNA sequences encoding fatty acyl elongases and desaturases, key genes involved in the LC-PUFA biosynthesis. Results show that C. estor expresses an elongase of very long-chain FA (Elovl)5 elongase and two Fads2 desaturases displaying Δ4 and Δ6/Δ5 specificities, thus allowing us to conclude that these three genes cover all the enzymatic abilities required for LC-PUFA biosynthesis from C18 PUFA. In addition, the specificities of the C. estor Fads2 enabled us to propose potential evolutionary patterns and mechanisms for subfunctionalization of Fads2 among fish lineages. PMID:24792929

  16. Integrative taxonomy identifies a new species of Phyllodistomum (Digenea: Gorgoderidae) from the twospot livebearer, Heterandria bimaculata (Teleostei: Poeciliidae), in Central Veracruz, Mexico.

    PubMed

    Razo-Mendivil, Ulises; Pérez-Ponce de León, Gerardo; Rubio-Godoy, Miguel

    2013-12-01

    Phyllodistomum inecoli n. sp. is described from the twospot livebearer, Heterandria bimaculata (Teleostei: Poeciliidae), collected in the Río La Antigua basin, Veracruz, Mexico. The new species is described and characterised by using a combination of morphology, scanning electron microscopy, and sequences of nuclear and mitochondrial genes. Diagnostic characters of the new species of Phyllodistomum include a genital pore opening at the level of the caecal bifurcation; oval vitellarium, situated just posterior to the ventral sucker and not extended laterally and anterior extracaecal uterine loops variable in extension (reaching the anterior, median or posterior margin of the ventral sucker). P. inecoli n. sp. most closely resembles P. brevicecum, a species described as a parasite of the central mudminnow, Umbra limi, in other parts of North America; however, the genital pore in P. brevicecum is situated between the caecal bifurcation and the ventral sucker, the ovary is larger, the vitellarium is lobed and extended laterally and the anterior portion of the uterus extends to the posterior margin of the ventral sucker. Comparison of about 1,500–2,200 nucleotides of cox1 and 28S rDNA and ITS1 strongly supports the status of P. inecoli as a new species. Bayesian inference analysis of combined datasets of 28S rDNA and cox1 sequences showed that P. inecoli n. sp. and the other species found in freshwater fishes of Mexico, including the species complex of P. lacustri, are not sister species. Phylogenetic analysis based on 28S rDNA sequences of several gorgoderid taxa revealed the close relationship of P. inecoli n. sp. with several species of Phyllodistomum, Gorgodera and Gorgoderina with cystocercous cercariae developing in sphaeriid bivalves. Dot-plot analysis of ITS1 sequences of P. inecoli n. sp. revealed the presence of eight repetitive elements with different length, which together represent almost half the length of ITS1.

  17. Ultrastructure and development of Nosema podocotyloidis n. sp. (Microsporidia), a hyperparasite of Podocotyloides magnatestis (Trematoda), a parasite of Parapristipoma octolineatum (Teleostei)

    PubMed Central

    2014-01-01

    Nosema podocotyloidis n. sp. (Microsporidia, Nosematidae) is described from Podocotyloides magnatestis (Trematoda: Opecoelidae), a parasite of the fish Parapristipoma octolineatum (Teleostei) in the Atlantic Ocean. Electron microscopy reveals that all the stages of the cycle (merogony and sporogony) are diplokaryotic and in direct contact with the cytoplasm of host cells. There is no sporophorous vesicle (pansporoblast). The earliest stages observed are meronts, which have a simple plasmic membrane. Their cytoplasm is granular, rich in ribosomes and contains some sacculi of endoplasmic reticulum. They divide by binary fission into diplokaryotic sporonts. The sporonts have a thick electron-dense wall. Their diplokaryon is slightly less electron-dense than the cytoplasm. The cytoplasm of more advanced sporonts has numerous electron-lucent vesicles. Sporonts with two diplokarya divide by binary fission into diplokaryotic sporoblasts. The older sporoblasts are irregular or elongate and the polar filament is in formation. Their cytoplasm is denser, with ribosomes and lamellae of granular endoplasmic reticulum. The sporoblasts evolve into spores. The mature spores are broadly oval and measure 3.6 (3.1–4.0) × 2.58 (1.8–3.3) μm. Their wall is 100–300 nm thick. The polar tube is isofilar with 11–16 coils, 130–155 nm in diameter and arranged in many layers in the centre of the spore. The polaroplast is divided into two regions: an outer electron-dense cup with granular content and lacking lamellae and an internal region, less electron-dense, composed of irregularly arranged sacs. The posterior vacuole, with an amorphous electron-dense content, is present. The new species is compared with other species of Nosema from trematodes. PMID:25174849

  18. Simultaneous analysis of five molecular markers provides a well-supported phylogenetic hypothesis for the living bony-tongue fishes (Osteoglossomorpha: Teleostei).

    PubMed

    Lavoué, Sébastien; Sullivan, John P

    2004-10-01

    Fishes of the Superorder Osteoglossomorpha (the "bonytongues") constitute a morphologically heterogeneous group of basal teleosts, including highly derived subgroups such as African electric fishes, the African butterfly fish, and Old World knifefishes. Lack of consensus among hypotheses of osteoglossomorph relationships advanced during the past 30 years may be due in part to the difficulty of identifying shared derived characters among the morphologically differentiated extant families of this group. In this study, we present a novel phylogenetic hypothesis for this group, based on the analysis of more than 4000 characters from five molecular markers (the mitochondrial cytochrome b, 12S and 16S rRNA genes, and the nuclear genes RAG2 and MLL). Our taxonomic sampling includes one representative of each extant non-mormyrid osteoglossomorph genus, one representative for the monophyletic family Mormyridae, and four outgroup taxa within the basal Teleostei. Maximum parsimony analysis of combined and equally weighted characters from the five molecular markers and Bayesian analysis provide a single, well-supported, hypothesis of osteoglossomorph interrelationships and show the group to be monophyletic. The tree topology is the following: (Hiodon alosoides, (Pantodon buchholzi, (((Osteoglossum bicirrhosum, Scleropages sp.), (Arapaima gigas, Heterotis niloticus)), ((Gymnarchus niloticus, Ivindomyrus opdenboschi), ((Notopterus notopterus, Chitala ornata), (Xenomystus nigri, Papyrocranus afer)))))). We compare our results with previously published phylogenetic hypotheses based on morpho-anatomical data. Additionally, we explore the consequences of the long terminal branch length for the taxon Pantodon buchholzi in our phylogenetic reconstruction and we use the obtained phylogenetic tree to reconstruct the evolutionary history of electroreception in the Notopteroidei.

  19. Ultrastructure and development of Nosema podocotyloidis n. sp. (Microsporidia), a hyperparasite of Podocotyloides magnatestis (Trematoda), a parasite of Parapristipoma octolineatum (Teleostei).

    PubMed

    Toguebaye, Bhen Sikina; Quilichini, Yann; Diagne, Papa Mbagnick; Marchand, Bernard

    2014-01-01

    Nosema podocotyloidis n. sp. (Microsporidia, Nosematidae) is described from Podocotyloides magnatestis (Trematoda: Opecoelidae), a parasite of the fish Parapristipoma octolineatum (Teleostei) in the Atlantic Ocean. Electron microscopy reveals that all the stages of the cycle (merogony and sporogony) are diplokaryotic and in direct contact with the cytoplasm of host cells. There is no sporophorous vesicle (pansporoblast). The earliest stages observed are meronts, which have a simple plasmic membrane. Their cytoplasm is granular, rich in ribosomes and contains some sacculi of endoplasmic reticulum. They divide by binary fission into diplokaryotic sporonts. The sporonts have a thick electron-dense wall. Their diplokaryon is slightly less electron-dense than the cytoplasm. The cytoplasm of more advanced sporonts has numerous electron-lucent vesicles. Sporonts with two diplokarya divide by binary fission into diplokaryotic sporoblasts. The older sporoblasts are irregular or elongate and the polar filament is in formation. Their cytoplasm is denser, with ribosomes and lamellae of granular endoplasmic reticulum. The sporoblasts evolve into spores. The mature spores are broadly oval and measure 3.6 (3.1-4.0) × 2.58 (1.8-3.3) μm. Their wall is 100-300 nm thick. The polar tube is isofilar with 11-16 coils, 130-155 nm in diameter and arranged in many layers in the centre of the spore. The polaroplast is divided into two regions: an outer electron-dense cup with granular content and lacking lamellae and an internal region, less electron-dense, composed of irregularly arranged sacs. The posterior vacuole, with an amorphous electron-dense content, is present. The new species is compared with other species of Nosema from trematodes.

  20. Ortholinea auratae n. sp. (Myxozoa, Ortholineidae) infecting the urinary bladder of the gilthead seabream Sparus aurata (Teleostei, Sparidae), in a Portuguese fish farm.

    PubMed

    Rangel, Luis F; Rocha, Sónia; Borkhanuddin, Muhammad H; Cech, Gábor; Castro, Ricardo; Casal, Graça; Azevedo, Carlos; Severino, Ricardo; Székely, Csaba; Santos, Maria J

    2014-09-01

    A new myxosporean species, Ortholinea auratae n. sp., is described from the gilthead seabream, Sparus aurata Linnaeus, 1758 (Teleostei, Sparidae) from a fish farm in Algarve, Portugal. Plasmodia and spores were found in the urinary bladder and, less frequently, in the posterior kidney. Plasmodia were polymorphic, presenting an irregular cellular membrane due to the presence of several peripheral projections, which in turn were covered by a glycocalyx-like sheet. Mature spores were subspherical in valvular view and ellipsoidal in sutural view, measuring 9.0 ± 0.3 (8.2-10.1) μm in length, 8.3 ± 0.4 (7.5-9.1) μm in width, and 7.2 ± 0.5 (6.3-8.4) μm in thickness. The two valves comprising the spores displayed an intricate pattern of surface ridges and were also enveloped by a glycocalyx-like sheet. Two subspherical polar capsules, 3.2 ± 0.1 (2.9-3.6) μm long and 2.7 ± 0.1 (2.4-2.9) μm wide, were located at the anterior pole and displayed divergent orientation. The polar filament coiled in three to four turns. The comprehensive analysis of the parasite's ultrastructural observations and molecular data for the small subunit (SSU) ribosomal DNA (rDNA) gene identify O. auratae n. sp. as a new species, clustering together with other myxosporeans infecting the excretory system to form a subclade of the main freshwater clade.

  1. Karyotypic diversity in four species of the genus Gymnotus Linnaeus, 1758 (Teleostei, Gymnotiformes, Gymnotidae): physical mapping of ribosomal genes and telomeric sequences

    PubMed Central

    Scacchetti, Priscilla Cardim; Pansonato-Alves, José Carlos; Utsunomia, Ricardo; Oliveira, Claudio; Foresti, Fausto

    2011-01-01

    Abstract Conventional (Giemsa, C-Banding, Ag-NORs, CMA3) and molecular (5S rDNA, 18S rDNA, telomeric sequences) cytogenetic studies were carried out in specimens of ten distinct fish populations of the genus Gymnotus (Gymnotus sylvius Albert and Fernandes-Matioli, 1999, Gymnotus inaequilabiatus Valenciennes, 1839, Gymnotus pantherinus Steindachner, 1908, and G. cf. carapo Linnaeus, 1758) from different Brazilian hydrographic basins. Gymnotus sylvius presented a diploid number of 40 chromosomes (22m+12sm+6st), Gymnotus pantherinus presented 52 chromosomes (32m+18sm+2st), while Gymnotus inaequilabiatus (42m+10sm+2a)and Gymnotus cf. carapo (38m+12sm+4st) presented 54 chromosomes. The C-banding technique revealed centromeric marks in all chromosomes of all species. Besides that, conspicuous blocks of heterochromatin were found interstitially on the chromosomes of Gymnotus inaequilabiatus, Gymnotus cf. carapo,and Gymnotus pantherinus. All four species showed single nucleolus organizing regions confirmed by results obtained through Ag-NORs and FISH experiments using 18S rDNA probes, which showed the NORs localized on the first chromosome pair in Gymnotus inaequilabiatus, Gymnotus cf. carapo,and Gymnotus pantherinus, and on pair 2 in Gymnotus sylvius. CMA3 staining revealed additional unrelated NORs marks in Gymnotus sylvius and Gymnotus pantherinus. The 5S rDNA probes revealed signals on one pair in Gymnotus sylvius and two pairs in Gymnotus pantherinus; Gymnotus inaequilabiatus had about seventeen pairs marked, and Gymnotus cf. carapo had about fifteen pairs marked. It is considered that the high amount of heterochromatin identified in the chromosomes of Gymnotus inaequilabiatus and Gymnotus cf. carapo could have facilitated the dispersion of 5S rDNA in these species. Interstitial signals were detected on the first metacentric pair of Gymnotus sylvius by telomeric probes (TTAGGG)n indicating the possible occurrence of chromosomal fusions in this species. The present

  2. A specimen of Paralycoptera Chang & Chou 1977 (Teleostei: Osteoglossoidei) from Hong Kong (China) with a potential Late Jurassic age that extends the temporal and geographical range of the genus

    PubMed Central

    Tse, Tze-Kei; Chang, Mee-mann

    2015-01-01

    We describe a Mesozoic fish Paralycoptera sp. (Teleostei: Osteoglossoidei), on the basis of a postcranial skeleton collected from the volcaniclastic mudstones of the Lai Chi Chong Formation of Hong Kong, China. The new finding—representing the city’s first Mesozoic fish—extends the geographical distribution of Paralycoptera from eastern mainland China into Hong Kong, demonstrating a wider distribution than previously appreciated for this genus. A radiometric age for the Lai Chi Chong Formation of 146.6 ± 0.2 Ma implies a temporal range expansion for Paralycoptera of approximately 40 million years back from the Early Cretaceous (∼110 Ma). However, spores found in the Formation suggest an Early Cretaceous age that is consistent with the existing age assignment to Paralycoptera. We argue that the proposed temporal range extension is genuine because it is based on recent high precision radiometric age data, but given the discrepancies with the biostratigraphic ages further investigation is needed to confirm this. This study provides an important step towards revealing Hong Kong’s Mesozoic vertebrate fauna and understanding its relationship to well-studied mainland Chinese ones. PMID:25834774

  3. A specimen of Paralycoptera Chang & Chou 1977 (Teleostei: Osteoglossoidei) from Hong Kong (China) with a potential Late Jurassic age that extends the temporal and geographical range of the genus.

    PubMed

    Tse, Tze-Kei; Pittman, Michael; Chang, Mee-Mann

    2015-01-01

    We describe a Mesozoic fish Paralycoptera sp. (Teleostei: Osteoglossoidei), on the basis of a postcranial skeleton collected from the volcaniclastic mudstones of the Lai Chi Chong Formation of Hong Kong, China. The new finding-representing the city's first Mesozoic fish-extends the geographical distribution of Paralycoptera from eastern mainland China into Hong Kong, demonstrating a wider distribution than previously appreciated for this genus. A radiometric age for the Lai Chi Chong Formation of 146.6 ± 0.2 Ma implies a temporal range expansion for Paralycoptera of approximately 40 million years back from the Early Cretaceous (∼110 Ma). However, spores found in the Formation suggest an Early Cretaceous age that is consistent with the existing age assignment to Paralycoptera. We argue that the proposed temporal range extension is genuine because it is based on recent high precision radiometric age data, but given the discrepancies with the biostratigraphic ages further investigation is needed to confirm this. This study provides an important step towards revealing Hong Kong's Mesozoic vertebrate fauna and understanding its relationship to well-studied mainland Chinese ones.

  4. [Population genetic structure of the char species of the Northern Kuril Islands and the rank of the Dolly Varden Char in the system of the genus Salvelinus (Salmonidae: Teleostei)].

    PubMed

    Shubina, E A; Ponomareva, E V; Gritsenko, O F

    2006-01-01

    Analysis of the taxonomic position of most species and forms of the char (genus Salvelinus, Salmonidae: Teleostei) was made based on RAPD-PCR. The material was represented by samples from 29 populations from the Kuril Islands, coast of the Sea of Okhotsk, Kamchatka, Chukotka, Taymyr, Transbaikalia, the Kola Peninsula, Svalbard, Finland, and North America. It was shown that the genus Salvelinus splits into three well-justified clusters: (1) all the forms assigned to the Salvelinus alpinus--S. malma complex; (2) two samples of the White-Spotted Char from the Southern Kuril Islands and from Kamchatka; (3) two North American species, S. fontinalis and S. namaycush (samples of the North American species S. confluentis were absent from the collection). Analysis of the absolute values of genetic disctances of the S. alpinus--S. malma forms relative to S. leucomaenis, S. fontinalis, and S. namaycush revealed distances approaching the species rank between the following isolates: Frolikh Char, Mountain Char, Black Lake Char, Goggle-Eyed Char, and Neyva Char. Samples of Dolly Varden currently considered as "S. malma", do not constitute a separate cluster, falling within the group of the Arctic char S. alpinus. This conclusion is supported by the analysis of the results of three series of experiments by R. Phillips on ITS1 ribosome genes (Pleute et al., 1992; Phillips et al., 1995; Phillips et al., 1999). This indicates the infraspecific rank of malma within S. alpinus. Isolated populations of "Salvethymus svetovidovi" from the lake Elgygytgyn (Chukotka Peninsula) and of the char from the lake Chyornoye (Onekotan Island), recently described as S. gritzenkoi (Vasil'eva, Stygar, 2000), fell withing the S. alpinus--S. malma complex, the Onekotan char grouped together with another isolate from the same island. Comparison of genetic distances between the samples showed that the differences between the two isolated of Onekotan and migratory forms of the Kuril Islands are

  5. Genomics and Mapping of Teleostei (Bony Fish)

    PubMed Central

    2003-01-01

    Until recently, the Human Genome Project held centre stage in the press releases concerning sequencing programmes. However, in October 2001, it was announced that the Japanese puffer fish (Takifugu rubripes, Fugu) was the second vertebrate organism to be sequenced to draft quality. Briefly, the spotlight was on fish genomes. There are currently two other fish species undergoing intensive sequencing, the green spotted puffer fish (Tetraodon nigroviridis) and the zebrafish (Danio rerio). But this trio are, in many ways, atypical representations of the current state of fish genomic research. The aim of this brief review is to demonstrate the complexity of fish as a group of vertebrates and to publicize the ‘lesser-known’ species, all of which have something to offer. PMID:18629122

  6. Influence of temperature on viral hemorrhagic septicemia (Genogroup IVa) in Pacific herring, Clupea pallasii Valenciennes

    USGS Publications Warehouse

    Hershberger, P.K.; Purcell, M.K.; Hart, L.M.; Gregg, J.L.; Thompson, R.L.; Garver, K.A.; Winton, J.R.

    2013-01-01

    An inverse relationship between water temperature and susceptibility of Pacific herring (Clupea pallasii) to viral hemorrhagic septicemia, genogroup IVa (VHS) was indicated by controlled exposure studies where cumulative mortalities, viral shedding rates, and viral persistence in survivors were greatest at the coolest exposure temperatures. Among groups of specific pathogen-free (SPF) Pacific herring maintained at 8, 11, and 15 °C, cumulative mortalities after waterborne exposure to viral hemorrhagic septicemia virus (VHSV) were 78%, 40%, and 13%, respectively. The prevalence of survivors with VHSV-positive tissues 25 d post-exposure was 64%, 16%, and 0% (at 8, 11 and 15 °C, respectively) with viral prevalence typically higher in brain tissues than in kidney/spleen tissue pools at each temperature. Similarly, geometric mean viral titers in brain tissues and kidney/spleen tissue pools decreased at higher temperatures, and kidney/spleen titers were generally 10-fold lower than those in brain tissues at each temperature. This inverse relationship between temperature and VHS severity was likely mediated by an enhanced immune response at the warmer temperatures, where a robust type I interferon response was indicated by rapid and significant upregulation of the herring Mx gene. The effect of relatively small temperature differences on the susceptibility of a natural host to VHS provides insights into conditions that preface periodic VHSV epizootics in wild populations throughout the NE Pacific.

  7. The complete mitochondrial DNA of the endemic shortfin silverside, Chirostoma humboldtianum (Valenciennes, 1835).

    PubMed

    Barriga-Sosa, Irene de los A; De León, Francisco J García; Del Río-Portilla, Miguel A

    2016-01-01

    The shortfin silverside Chirostoma humboldtianum, is an endemic fish from the Mesa Central of Mexico, it is considered the "ancestral" species of the "peces blancos" and plays an important role as a potential species for aquaculture. Here we sequence its mitogenome (Genbank accession number KJ921739), which has a total length of 16,447 bp, and the arrangement consist of 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes and 22 transfer RNA similar to other Atheriniformes. This mitogenome will be useful for phylogenetic, population and phylogeographic studies of this and other important atherinopsid species.

  8. Exogenous enzyme complex prevents intestinal soybean meal-induced enteritis in Mugil liza (Valenciennes, 1836) juvenile.

    PubMed

    Ramos, Leonardo R V; Pedrosa, Virgínia F; Mori, Agnes; Andrade, Carlos F F DE; Romano, Luis A; Abreu, Paulo C; Tesser, Marcelo B

    2017-02-09

    Four soybean meal-based diets containing increasing levels of an enzyme complex (E50, E100, E150 and E200 at 50, 100, 150 and 200 g ton-1, respectively) and one soybean meal-based diet without the enzyme complex (E0) were fed in triplicate to M. liza juveniles in a semi-static flow system with 20 fish per tank for 75 days. There were no differences between the treatments for animal performance parameters, but fish fed the enzyme complex treatment exhibited significantly (P<0.05) higher values of calcium bone retention compared with control fish. Although there was no relationship between bacterial counts in different sections of the gastrointestinal tract or enzyme levels, filamentous bacteria were increased in E50 compared with E150. All of the treatments resulted in higher bacterial counts in the stomach than in intestinal segments. Histological screening showed serious to moderate infiltration of inflammatory cells, modification in villus morphology and necrosis in some cases in fish fed the E0 diet. In addition, fish from the E0 treatment exhibited significantly (P<0.05) lower lipid deposition in the peritoneal cavity. Therefore, the use of low levels of exogenous enzyme is recommended in diets for M. liza when soybean meal is used as the main source of protein.

  9. Effects of sediment burial on grass carp, Ctenopharyngodon idella (Valenciennes,1844), eggs

    USGS Publications Warehouse

    George, Amy E.; Chapman, Duane C.; Deters, Joseph E.; Erwin, Susannah O.; Hayer, Cari-Ann

    2015-01-01

    It is thought that grass carp (Ctenopharyngodon idella) eggs must remain suspended in the water column in order to hatch successfully. Using sand, the effects of varying sediment levels on grass carp eggs were tested at different developmental states and temperatures. Survival was high (15–35%, depending on temperature and trial) in the unburied treatment where eggs rested on a sand bed but were not covered by sediment. Survival was lower in the partial burial (5–10%) and very low (0–4%) in the full burial treatment. In all treatments, delayed hatching (organisms remaining in membranes past the stage of hatching competence) was noted. Deformities such as missing heads and pericardial edema occurred at high rates in the partial and full burials. Eggs that come in contact with the benthos and are resuspended in the water column should be considered in embryonic drift models.

  10. Ovarian development of a river catfish Hemibagrus nemurus (Valenciennes, 1840) in captivity.

    PubMed

    Adebiyi, Fatimat Adenike; Siraj, Siti Shapor; Harmin, Sharr Azni; Christianus, Annie

    2011-11-01

    Hemibagrus nemurus is a riverine catfish with high economic and nutritive values. Investigations on ovarian development of this fish were carried out to determine the mode of ovarian development and describe the oocyte developmental stages. Histological studies were done on ovaries using light microscopy and scanning electron microscopy. Fish were sampled monthly for a period of six months (August 2009 to January 2010). The mean oocyte diameter (OD) ranged from 871 ± 161.41 µm to 1,167 ± 26.77 µm and the highest OD was in November. Oocyte size-frequency distribution showed a polymodal distribution. The mean gonadosomatic index (GSI) ranged from 1.14 ± 0.87% to 7.06 ± 1.40% and highest GSI was in November. The ovaries exhibited three phases of oocyte growth, which were primary growth, secondary growth and maturation phases. Based on histological criteria, the oocyte developmental stages were divided into seven stages as chromatin nucleolar, early perinucleolar, late perinucleolar, cortical alveolar, vitellogenesis, mature oocyte and germinal vesicle migration stages. All the seven stages of oocyte development were observed in the ovaries. Oogonia were always present throughout the developmental stages. The ovaries had more than two stages of oocyte development. This is the first report on the mode of ovarian development of H. nemurus. These findings indicated that H. nemurus has asynchronous mode of ovarian development and is capable of spawning several times in a year under favourable conditions.

  11. Bone development of the skull, pectoral and pelvic fins in Seriola rivoliana (Valenciennes, 1833) larvae.

    PubMed

    Mesa-Rodríguez, A; Hernández-Cruz, C M; Betancor, M B; Fernández-Palacios, H; Izquierdo, M S; Roo, J

    2016-12-01

    Skull, pectoral and pelvic fin bone structures in longfin yellowtail Seriola rivoliana were studied from 3.43 ± 0.15 to 16.20 ± 0.73 mm standard length (SL) specimens. The S. rivoliana skull started to mineralize with the appearance of the parasphenoid and maxillary by 3.43 ± 0.15 mm SL at the neurocranium and jaw regions, respectively. The first pectoral structure to mineralize was the cleithrum at 3.75 ± 0.14 mm SL shortly followed by the supracleithrum and posttemporal. The pelvic fin started by 6.16 ± 0.32 mm SL with the spine and continued with the soft rays and basipterygium. The present study determined the onset of the skull, pectoral and pelvic fin mineralization. These results might be used as a reference for future studies in S. rivoliana or related species.

  12. Genetic identification of bucktooth parrotfish Sparisoma radians (Valenciennes, 1840) (Labridae, Scarinae) by chromosomal and molecular markers.

    PubMed

    Paim, Fabilene Gomes; Brandão, José Henrique Souza Galdino; Sampaio, Iracilda; de Mello Affonso, Paulo Roberto Antunes; Diniz, Débora

    2014-10-01

    Parrotfishes (Labridae, Scarinae) comprise a large marine fish group of difficult identification, particularly during juvenile phase when the typical morphology and coloration of adults are absent. Therefore, the goal of this study was to test cytogenetic markers and DNA barcoding in the identification of bucktooth parrtotfish Sparisoma radians from the northeastern coast of Brazil. Sequencing of cytochrome c oxidase subunit I (COI) confirmed all studied samples as S. radians, and all showed high similarity (99-100%) with Caribbean populations. The karyotype of this species was divergent from most marine Perciformes, being composed of 2n = 46 chromosomes. These consisted of a large number of metacentric and submetacentric pairs with small amounts of heterochromatin and GC-rich single nucleolar organizer regions (NORs) not syntenic to 5S rDNA clusters. These are the first data about DNA barcoding in parrotfish from the Brazilian province and the first refined chromosomal analysis in Scarinae, providing useful data to a reliable genetic identification of S. radians.

  13. Genetic identification of bucktooth parrotfish Sparisoma radians (Valenciennes, 1840) (Labridae, Scarinae) by chromosomal and molecular markers

    PubMed Central

    Paim, Fabilene Gomes; Brandão, José Henrique Souza Galdino; Sampaio, Iracilda; de Mello Affonso, Paulo Roberto Antunes; Diniz, Débora

    2014-01-01

    Parrotfishes (Labridae, Scarinae) comprise a large marine fish group of difficult identification, particularly during juvenile phase when the typical morphology and coloration of adults are absent. Therefore, the goal of this study was to test cytogenetic markers and DNA barcoding in the identification of bucktooth parrtotfish Sparisoma radians from the northeastern coast of Brazil. Sequencing of cytochrome c oxidase subunit I (COI) confirmed all studied samples as S. radians, and all showed high similarity (99–100%) with Caribbean populations. The karyotype of this species was divergent from most marine Perciformes, being composed of 2n = 46 chromosomes. These consisted of a large number of metacentric and submetacentric pairs with small amounts of heterochromatin and GC-rich single nucleolar organizer regions (NORs) not syntenic to 5S rDNA clusters. These are the first data about DNA barcoding in parrotfish from the Brazilian province and the first refined chromosomal analysis in Scarinae, providing useful data to a reliable genetic identification of S. radians. PMID:25505839

  14. Banded karyotype of the Konya wild sheep (Ovis orientalis anatolica Valenciennes, 1856) from Turkey.

    PubMed

    Arslan, Atilla; Zima, Jan

    2011-01-01

    Thekaryotype, C-banding, and nucleoar organizer regions (NORs) of eight specimens ofKonya wild sheepfrom Turkey were examined. The complement included six large metacentric autosomes, 46 acrocentric autosomes of decreasing size, a medium-sized acrocentric X chromosome, and a small bi-armed Y chromosome (the diploid chromosome number 2n=54, the number of autosomal arms NFa=58, the number of chromosome arms NF=61). G-banding allowed reliable identification of all the chromosome pairs and the pairing of homologous elements. All the autosomes possessed distinct centromeric or pericentromeric C-positive bands. The X chromosome had a pericentromeric C-positive band, and the Y chromosome was entirely C-heterochromatic. The NORs were located in the terminal regions of the long arms of three metacentric and two acrocentric autosomes. The karyotype of the Konya wild sheep and its banding patterns are quite similar to chromosome complement reported in domestic sheep and European mouflon.

  15. Quantitative genetic properties of four measures of deformity in yellowtail kingfish Seriola lalandi Valenciennes, 1833.

    PubMed

    Nguyen, N H; Whatmore, P; Miller, A; Knibb, W

    2016-02-01

    The main aim of this study was to estimate the heritability for four measures of deformity and their genetic associations with growth (body weight and length), carcass (fillet weight and yield) and flesh-quality (fillet fat content) traits in yellowtail kingfish Seriola lalandi. The observed major deformities included lower jaw, nasal erosion, deformed operculum and skinny fish on 480 individuals from 22 families at Clean Seas Tuna Ltd. They were typically recorded as binary traits (presence or absence) and were analysed separately by both threshold generalized models and standard animal mixed models. Consistency of the models was evaluated by calculating simple Pearson correlation of breeding values of full-sib families for jaw deformity. Genetic and phenotypic correlations among traits were estimated using a multitrait linear mixed model in ASReml. Both threshold and linear mixed model analysis showed that there is additive genetic variation in the four measures of deformity, with the estimates of heritability obtained from the former (threshold) models on liability scale ranging from 0.14 to 0.66 (SE 0.32-0.56) and from the latter (linear animal and sire) models on original (observed) scale, 0.01-0.23 (SE 0.03-0.16). When the estimates on the underlying liability were transformed to the observed scale (0, 1), they were generally consistent between threshold and linear mixed models. Phenotypic correlations among deformity traits were weak (close to zero). The genetic correlations among deformity traits were not significantly different from zero. Body weight and fillet carcass showed significant positive genetic correlations with jaw deformity (0.75 and 0.95, respectively). Genetic correlation between body weight and operculum was negative (-0.51, P < 0.05). The genetic correlations' estimates of body and carcass traits with other deformity were not significant due to their relatively high standard errors. Our results showed that there are prospects for genetic selection to improve deformity in yellowtail kingfish and that measures of deformity should be included in the recording scheme, breeding objectives and selection index in practical selective breeding programmes due to the antagonistic genetic correlations of deformed jaws with body and carcass performance.

  16. Water quality and zooplankton in tanks with larvae of Brycon Orbignyanus (Valenciennes, 1949).

    PubMed

    Sipaúba-Tavares, L H; Alvarez, E J da S; Braga, F M de S

    2008-02-01

    Due to the importance of water variables conditions and available food in the development and survival of fish larvae, the current research evaluates the effects of two different food treatments (ration + zooplankton and only zooplankton) and water quality in tanks with Brycon orbignyanus larvae. Total water transparency (45 cm) has been mainly associated with short residence time, continuous water flow and shallowness. Dissolved oxygen ranged between 1.32 and 7.00 mg.L(-1) in tanks with ration + zooplankton and between 1.82 and 7.60 mg.L(-1) in tanks with only zooplankton treatments. Nutrients were directly affected by the addition of ration in water, with the exception of nitrite. Ten Rotifera species were found represented by high densities, ranging between 8.7 x 10(5) and 1.3 x 10(6) org.m(-3), throughout the experimental period (January to March/1996). Cladocera had the lowest density in the four tanks under analysis and ranged between 4.7 x 10(4) and 2.1 x 10(5) org.m(-3) for the six species. Diaphanosoma birgei has been classified as the most frequent species. Since ration + zooplankton produced better larvae yield, this treatment is recommended for Brycon orbignyanus larvae.

  17. Molecular phylogenetics of the Neotropical fish family Prochilodontidae (Teleostei: Characiformes).

    PubMed

    Melo, Bruno F; Sidlauskas, Brian L; Hoekzema, Kendra; Frable, Benjamin W; Vari, Richard P; Oliveira, Claudio

    2016-09-01

    Migratory detritivores of the characiform family Prochilodontidae occur throughout the freshwaters of much of South America. Prochilodontids often form massive populations and many species achieve substantial body sizes; a combination that makes them one of the most commercially important fish groups on the continent. Their economic significance notwithstanding, prochilodontids have never been the subject of a comprehensive molecular phylogenetic analysis. Using three mitochondrial and three nuclear loci spanning all prochilodontid species, we generated a novel phylogenetic hypothesis for the family. Our results strongly support monophyly of the family and the three included genera. A novel, highly supported placement of Ichthyoelephas sister to the clade containing Prochilodus and Semaprochilodus diverges from a previous morphological hypothesis. Most previously hypothesized interspecific relationships are corroborated and some longstanding polytomies within Prochilodus and Semaprochilodus are resolved. The morphologically similar P. brevis, P. lacustris, P. nigricans and P. rubrotaeniatus are embedded within what is herein designated as the P. nigricans group. Species limits and distributions of these species are problematic and the group clearly merits taxonomic revision.

  18. Glycoproteins histochemistry of the gills of Odontesthes bonariensis (Teleostei, Atherinopsidae).

    PubMed

    Díaz, A O; García, A M; Escalante, A H; Goldemberg, A L

    2010-11-01

    The histochemistry of glycoproteins (GP) in the mucous cells of the gills of the silverside Odontesthes bonariensis was identified with: (1) oxidizable vicinal diols; (2) sialic acid and some of their chain variants, carbon 7 ((7) C), carbon 8 ((8) C) or carbon 9 ((9) C); (3) sialic acid residues without O-acyl substitution and with O-acyl substitution at (7) C, (8) C or (9) C; (4) carboxyl groups and (5) sulphate groups. A battery of seven biotinylated lectins allowed GPs sugar residues to be distinguished. Mucous cells showed the presence of neutral, sulphated and sialylated GPs. Dolichos biflorus agglutinin (DBA) and Glycine max agglutinin (SBA) showed strong positive staining; Arachis hypogaea agglutinin (PNA), Ricinus communis agglutinin-I (RCA-I) and Triticum vulgaris agglutinin (WGA) showed moderate staining, while Ulex europaeus agglutinin-I (UEA-I) was completely negative.

  19. Parallel speciation in Astyanax cave fish (Teleostei) in Northern Mexico.

    PubMed

    Strecker, Ulrike; Hausdorf, Bernhard; Wilkens, Horst

    2012-01-01

    We investigated differentiation processes in the Neotropical fish Astyanax that represents a model system for examining adaptation to caves, including regressive evolution. In particular, we analyzed microsatellite and mitochondrial data of seven cave and seven surface populations from Mexico to test whether the evolution of the cave fish represents a case of parallel evolution. Our data revealed that Astyanax invaded northern Mexico across the Trans-Mexican Volcanic Belt at least three times and that populations of all three invasions adapted to subterranean habitats. Significant differentiation was found between the cave and surface populations. We did not observe gene flow between the strongly eye and pigment reduced old cave populations (Sabinos, Tinaja, Pachon) and the surface fish, even when syntopically occurring like in Yerbaniz cave. Little gene flow, if any, was found between cave populations, which are variable in eye and pigmentation (Micos, Chica, Caballo Moro caves), and surface fish. This suggests that the variability is due to their more recent origin rather than to hybridization. Finally, admixture of the young Chica cave fish population with nuclear markers from older cave fish demonstrates that gene flow between populations that independently colonized caves occurs. Thus, all criteria of parallel speciation are fulfilled. Moreover, the microsatellite data provide evidence that two co-occurring groups with small sunken eyes and externally visible eyes, respectively, differentiated within the partly lightened Caballo Moro karst window cave and might represent an example for incipient sympatric speciation.

  20. Mahseers genera Tor and Neolissochilus (Teleostei: Cyprinidae) from southern Vietnam.

    PubMed

    Hoàng, Huy Đức; Phạm, Hùng Mạnh; Durand, Jean-Dominique; Trần, Ngân Trọng; Phan, Phúc Đình

    2015-08-25

    Two new species and two new basin records of mahseers in the genera Tor and Neolissochilus are described from the upper Krong No and middle Đồng Nai drainages of the Langbiang Plateau in southern Vietnam. These new species and new records are known from streams and rivers in montane mixed pine and evergreen forests between 140 and 1112 m. Their populations are isolated in the Sre Pok River of the Mekong basin, the middle of the Đồng Nai basin, and the An Lão River. Both new species are differentiated from their congeners by a combination of the following characters: 23-24 lateral scales, 9-10 predorsal scales, 2/7 or 1/8 pelvic-fin rays, mouth position, median lobe of lower lip, rostral hood, colour in life and by divergent mitochondrial DNA. Tor mekongensis sp. nov. is differentiated from Tor dongnaiensis sp. nov. by the number of transverse scale rows (3/1/2 vs. 4/1/2), number of pelvic-fin rays (2/7 vs. 1/8), a blunt rostral hood vs. pointed, caudal-fin lobes that are equal vs. unequal, and by mitochondrial DNA (0.7% sequence divergence). Molecular evidence identifies both species as members of the genus Tor and distinct from all congeners sampled (uncorrected sequence divergences >1.9% for all Tor species for which homologous COI sequences are available). Tor sinensis is recorded in the Krong No and the Sre Pok rivers, further south of its known distribution. Polymorphism is described in Neolissochilus stracheyi with a Tor-like morph and a Neolissochilus-like morph.

  1. Growth and mortality of larval Myctophum affine (Myctophidae, Teleostei).

    PubMed

    Namiki, C; Katsuragawa, M; Zani-Teixeira, M L

    2015-04-01

    The growth and mortality rates of Myctophum affine larvae were analysed based on samples collected during the austral summer and winter of 2002 from south-eastern Brazilian waters. The larvae ranged in size from 2·75 to 14·00 mm standard length (L(S)). Daily increment counts from 82 sagittal otoliths showed that the age of M. affine ranged from 2 to 28 days. Three models were applied to estimate the growth rate: linear regression, exponential model and Laird-Gompertz model. The exponential model best fitted the data, and L(0) values from exponential and Laird-Gompertz models were close to the smallest larva reported in the literature (c. 2·5 mm L(S)). The average growth rate (0·33 mm day(-1)) was intermediate among lanternfishes. The mortality rate (12%) during the larval period was below average compared with other marine fish species but similar to some epipelagic fishes that occur in the area.

  2. Distribution and Segregation of Two Sympatric Brevoortia Species (Teleostei: Clupeidae)

    NASA Astrophysics Data System (ADS)

    Castillo-Rivera, M.; Kobelkowsky, A.

    2000-05-01

    The authors described and analysed the temporal and spatial distribution and segregation patterns ofBrevoortia patronus and B. gunteri, in a coastal lagoon of Veracruz, Mexico. A total of 394 individuals of B. gunteri (mean SL of 61·7 mm) and 378 of B. patronus (mean SL of 128·0) were collected, in 189 monthly and 48 diel (24-h cycles) samples. Both species showed two catchability peaks-one during March-May (dry season) and the second in July-October (rainy season)-and these peaks were related with the two primary production pulses in the system. These patterns were slightly different for each species, the first peak being more important for B. gunteri (68·6%), and the second for B. patronus (78·2%). Brevoortia patronus number was correlated with rainfall (P<0·01), and the relative abundance of both species was correlated with salinity (P<0·05). In 24-h cycle analysis, the two species were more abundant around midday (10:00 to 14:00 h), with few individuals captured during the night, and this behaviour was probably related to light intensity and their trophic activities. Moreover, no diel separation between species was observed. Spatially, B. gunteri was principally captured (67·4%) in sites with higher salinities and with no submerged vegetation, and B. patronus was mainly captured (70·9%) in sites with low salinity and with dense beds of Ruppia maritima. Thus, the authors consider salinity as an important factor in the seasonal and spatial segregation of Brevoortia species, with B. gunteri common in periods and zones with higher salinity and B. patronus in periods and areas of low salinity. The results presented here suggest that these segregation patterns permit resource partitioning between these species and facilitate their local co-existence.

  3. A Time-Calibrated Mitogenome Phylogeny of Catfish (Teleostei: Siluriformes)

    PubMed Central

    Kappas, Ilias; Vittas, Spiros; Pantzartzi, Chrysoula N.; Drosopoulou, Elena; Scouras, Zacharias G.

    2016-01-01

    A very significant part of the world’s freshwater ichthyofauna is represented by ancient, exceptionally diverse and cosmopolitan ray-finned teleosts of the order Siluriformes. Over the years, catfish have been established as an exemplary model for probing historical biogeography at various scales. Yet, several tantalizing gaps still exist in their phylogenetic history, timeline and mode of diversification. Here, we re-examine the phylogeny of catfish by assembling and analyzing almost all publicly available mitogenome data. We constructed an ingroup matrix of 62 full-length mitogenome sequences from 20 catfish families together with four cypriniform outgroups, spanning 15,557 positions in total. Partitioned maximum likelihood analyses and Bayesian relaxed clock dating using fossil age constraints provide some useful and novel insights into the evolutionary history of this group. Loricarioidei are recovered as the first siluriform group to diversify, rendering Neotropics the cradle of the order. The next deepest clade is the South American Diplomystoidei placed as a sister group to all the remaining Siluroidei. The two multifamilial clades of “Big Asia” and “Big Africa” are also recovered, albeit nodal support for the latter is poor. Within “Big Asia”, Bagridae are clearly polyphyletic. Other interfamilial relationships, including Clariidae + Heteropneustidae, Doradidae + Auchenipteridae and Ictaluridae + Cranoglanididae are robustly resolved. Our chronogram shows that siluriforms have a Pangaean origin, at least as far back as the Early Cretaceous. The inferred timeline of the basal splits corroborates the “Out-of-South America” hypothesis and accords well with the fossil record. The divergence of Siluroidei most likely postdated the final separation of Africa and South America. An appealing case of phylogenetic affinity elaborated by biogeographic dispersal is exemplified by the Early Paleogene split between the Southeast Asian Cranoglanididae and Ictaluridae, with the latter radiating into North America’s freshwater realm by Eocene. The end of Cretaceous probably concludes the major bout of diversification at the family level while with the dawn of the Cenozoic a prolific radiation is evident at the generic level. PMID:27907107

  4. Phylogenetic placement of enigmatic percomorph families (Teleostei: Percomorphaceae).

    PubMed

    Sanciangco, Millicent D; Carpenter, Kent E; Betancur-R, Ricardo

    2016-01-01

    Percomorphs are a large and diverse group of spiny-finned fishes that have come to be known as the "bush at the top" due to their persistent lack of phylogenetic resolution. Recently, the broader Euteleost Tree of Life project (EToL) inferred a well-supported phylogenetic hypothesis that groups the diversity of percomorphs into nine well-supported series (supraordinal groups): Ophidiaria, Batrachoidaria, Gobiaria, Syngnatharia, Pelagiaria, Anabantaria, Carangaria, Ovalentaria, and Eupercaria. The EToL also provided, for the first time, a monophyletic definition of Perciformes - the largest order of vertebrates. Despite significant progress made in accommodating the diversity of percomorph taxa into major clades, some 62 families (most previously placed in "Perciformes", as traditionally defined) were not examined by the EToL. Here, we provide evidence for the phylogenetic affinities of 10 of those 62 families, seven of which have largely remained enigmatic. This expanded taxonomic sampling also provides further support for the nine EToL supraordinal series. We examined sequences from 21 genes previously used by the EToL and added two fast-evolving mitochondrial markers in an attempt to increase resolution within the rapid percomorph radiations. We restricted the taxonomic sampling to 1229 percomorph species, including expanded sampling from recent studies. Results of maximum likelihood analysis revealed that bathyclupeids (Bathyclupeidae), galjoen fishes (Dichistiidae), kelpfishes (Chironemidae), marblefishes (Aplodactylidae), trumpeters (Latridae), barbeled grunters (Hapalogenyidae), slopefishes (Symphysanodontidae), and picarel porgies (formerly Centracanthidae) are members of the series Eupercaria ("new bush at the top"). The picarel porgies and porgies (Sparidae) are now placed in the same family (Sparidae). Our analyses suggest a close affinity between the orders Spariformes (including Lethrinidae, Nemipteridae and Sparidae) and Lobotiformes (including the tripletails or Lobotidae, the barbeled grunters, and tigerperches or Datnioididae), albeit support for this group is low. None of the newly examined families belong in the order Perciformes, as recently defined. Finally, we confirm results from other recent studies that place the Australasian salmons (Arripidae) within Pelagiaria, and the false trevallies (Lactariidae) close to flatfishes, jacks, and trevallies, within Carangaria.

  5. Complete mitochondrial genome of Florida pompano Trachinotus carolinus (Teleostei, Carangidae).

    PubMed

    Zhang, Dianchang; Wang, Long; Guo, Huayang; Ma, Zhenhua; Zhang, Nan; Lin, Junda; Jiang, Shigui

    2016-01-01

    The complete mitochondrial genome sequence of Florida pompano Trachinotus carolinus was determined by the overlapped polymerase chain reaction. The complete mitochondrial DNA sequence is 16,544 bp in length. It consists of 13 protein-coding genes, 22 transfer RNA genes, two rRNA genes and two non-coding regions. Overall base composition of its mitochondrial genome is estimated to be 28.68% for A, 16.27% for G, 26.00% for T, 29.06% for C, respectively, with a high A+T content (54.68%). The control region contains three conserved sequence blocks, a termination-associated sequence and a TATA box. The sequence data of T. carolinus can provide useful information for the studies on population structure, molecular systematic, stock evaluation and conservation genetics. It is also helpful to develop the rational management strategies for T. carolinus resource.

  6. Evolutionary history of anglerfishes (Teleostei: Lophiiformes): a mitogenomic perspective

    PubMed Central

    2010-01-01

    Background The teleost order Lophiiformes, commonly known as the anglerfishes, contains a diverse array of marine fishes, ranging from benthic shallow-water dwellers to highly modified deep-sea midwater species. They comprise 321 living species placed in 68 genera, 18 families and 5 suborders, but approximately half of the species diversity is occupied by deep-sea ceratioids distributed among 11 families. The evolutionary origins of such remarkable habitat and species diversity, however, remain elusive because of the lack of fresh material for a majority of the deep-sea ceratioids and incompleteness of the fossil record across all of the Lophiiformes. To obtain a comprehensive picture of the phylogeny and evolutionary history of the anglerfishes, we assembled whole mitochondrial genome (mitogenome) sequences from 39 lophiiforms (33 newly determined during this study) representing all five suborders and 17 of the 18 families. Sequences of 77 higher teleosts including the 39 lophiiform sequences were unambiguously aligned and subjected to phylogenetic analysis and divergence time estimation. Results Partitioned maximum likelihood analysis confidently recovered monophyly for all of the higher taxa (including the order itself) with the exception of the Thaumatichthyidae (Lasiognathus was deeply nested within the Oneirodidae). The mitogenomic trees strongly support the most basal and an apical position of the Lophioidei and a clade comprising Chaunacoidei + Ceratioidei, respectively, although alternative phylogenetic positions of the remaining two suborders (Antennarioidei and Ogcocephaloidei) with respect to the above two lineages are statistically indistinguishable. While morphology-based intra-subordinal relationships for relatively shallow, benthic dwellers (Lophioidei, Antennarioidei, Ogcocephaloidei, Chaunacoidei) are either congruent with or statistically indistinguishable from the present mitogenomic tree, those of the principally deep-sea midwater dwellers (Ceratioidei) cannot be reconciled with the molecular phylogeny. A relaxed molecular-clock Bayesian analysis of the divergence times suggests that all of the subordinal diversifications have occurred during a relatively short time period between 100 and 130 Myr ago (early to mid Cretaceous). Conclusions The mitogenomic analyses revealed previously unappreciated phylogenetic relationships among the lophiiform suborders and ceratioid familes. Although the latter relationships cannot be reconciled with the earlier hypotheses based on morphology, we found that simple exclusion of the reductive or simplified characters can alleviate some of the conflict. The acquisition of novel features, such as male dwarfism, bioluminescent lures, and unique reproductive modes allowed the deep-sea ceratioids to diversify rapidly in a largely unexploited, food-poor bathypelagic zone (200-2000 m depth) relative to the other lophiiforms occurring in shallow coastal areas. PMID:20178642

  7. The Dorsal Pallium in Zebrafish, Danio rerio (Cyprinidae, Teleostei)

    PubMed Central

    Mueller, Thomas; Dong, Zhiqiang; Berberoglu, Michael A.; Guo, Su

    2011-01-01

    Zebrafish as a neurogenetic model system depends on the correct neuroanatomical understanding of its brain organization. Here, we address the unresolved question regarding a possible zebrafish homologue of the dorsal pallial division, the region that in mammals gives rise to the isocortex. Analyzing the distributions of nicotine adenine dinucleotide phosphate diphorase (NADPHd) activity and parvalbumin in the anterior zebrafish telencephalon, we show that against previous assumptions the central (Dc) zone possesses its own germinative region in the dorsal proliferative zone. We define the central (Dc) zone as topologically corresponding to the dorsal pallial division of other vertebrates (mammalian isocortex). In addition, we confirm through BrdU-labeling experiments that the posterior (Dp) zone is formed by radial migration and homologous to the mammalian piriform cortex. Based on our results, we propose a new developmental and organizational model of the zebrafish pallium—one which is the result of a complex outward-inward folding. PMID:21219890

  8. The complete mitochondrial genome of Gobiobotia filifer (Teleostei, Cypriniformes: Cyprinidae).

    PubMed

    Li, Qiang; Liu, Ya; Zhou, Jian; Gong, Quan; Li, Hua; Lai, Jiansheng; Li, Lianman

    2016-09-01

    The Gobiobotia filifer is a small economic fish which distributes in the upstream of Yangtze River and its distributaries. For the environmental pollution and overfishing, its population declined drastically in recent decades, so it is essential to protect its resource. In this study, the complete mitochondrial genome sequence of G. filifer was determined with PCR technology, which contains 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and a non-coding control region with the total length of 16,613 bp. The order and composition of genes were similar to most of the other teleost fish. Most of the genes were encoded on heavy strand, except for ND6 genes and eight tRNAs. Just like most other vertebrates, the bias of G and C has been found in different genes/regions. The complete mitochondrial genome sequence of G. filifer would contribute to better understand evolution of this lineage, population genetics, and will help administrative department to make rules and laws to protect this lineage.

  9. A description on pharyngeal jaw apparatus and diets of halfbeak fish Zenarchopterus buffonis (Valenciennes 1847) in Malaysian waters

    NASA Astrophysics Data System (ADS)

    Abidin, Diana Atiqah Zainal; Hashim, Marina; Das, Simon K.; Ghaffar, Mazlan Abd.

    2015-09-01

    Information on the feeding mechanism and diet of halfbeak fish species in harsh estuarine environment ecosystem is still lacking. The present study investigates the fine structure of pharyngeal jaw apparatus and diets of halfbeak fish Zenarchopterus buffonis. A total of 84 halfbeak fish samples have been collected from the coastal water of Peninsular Malaysia using fishing rod. Scanning electron microscopy was used to examine the micrographs of fine microstructure of the pharyngeal teeth. The fundamental anatomy of pharyngeal jaw apparatus displayed that the upper pharyngeal jaw (third pharyngobranchials) displays larger size of hook-like or tricuspid teeth which was analogous to tricuspid morphology. The lower pharyngeal jaw (fifth ceratobranchial) bears mainly conical teeth and appears triangular shape with two, short projections. The estimated TROPH values (1 - 3.2±0.55) denoted that halfbeak fish were omnivores in nature. The findings of this study was found to be useful as a baseline information for a better representation of the trophic flows associated with large medium and small surface water fishes.

  10. Efficacy of a glycoprotein DNA vaccine against viral haemorrhagic septicaemia (VHS) in Pacific herring, Clupea pallasii Valenciennes

    USGS Publications Warehouse

    Hart, L.M.; Lorenzen, Niels; LaPatra, S.E.; Grady, C.A.; Roon, S.E.; O’Reilly, J.; Gregg, J.L.; Hershberger, P.K.

    2012-01-01

    Viral haemorrhagic septicaemia virus (VHSV) and its associated disease state, viral haemorrhagic septicaemia (VHS), is hypothesized to be a proximate factor accounting for the decline and failed recovery of Pacific herring populations in Prince William Sound, AK (Marty et al. 1998, 2003, 2010). Survivors of laboratory-induced VHSV epizootics develop resistance to subsequent viral exposure (Kocan et al. 2001; Hershberger et al. 2007, 2010), which is likely the result of immune system recognition of the viral glycoprotein (G) (Lecocq-Xhonneux et al. 1994), a surface antigen that contains neutralizing epitopes (Lorenzen, Olesen & Jorgensen 1990; Jørgensen et al. 1995) and cell attachment domains (Lecocq-Xhonneux et al. 1994; Estepa & Coll 1996). These properties have proven useful in the development of G-gene-based DNA vaccines for VHSV and a related rhabdovirus, infectious haematopoietic necrosis virus (IHNV) (Anderson et al. 1996; Heppell et al. 1998; Corbeil et al. 1999; Einer-Jensen et al. 2009). Rainbow trout fingerlings, Oncorhynchus mykiss (Walbaum), vaccinated with 1 µg of either the VHS or IHN vaccine are protected from VHS when exposed to virus as early as 4 days (44 degree days) post-vaccination (p.v.) (Lorenzen et al. 2002). At later time points (80 days p.v.; 880 degree days), the level of cross-protection against VHS by IHN vaccination is either completely lost (60 days p.v.; 660 degree days) (3 g rainbow trout; 1 µg vaccine dose) (Lorenzen et al. 2002) or present at intermediate levels (6.5 g rainbow trout; 1 µg vaccine dose) (Einer-Jensen et al. 2009). Comparatively, VHS vaccination remains effective as long as 9 months (2520 degree days) p.v. (100 g rainbow trout; 0.5 µg vaccine dose) (McLauchlan et al. 2003). These results suggest that IHN and VHS vaccination activate a rapid transitory innate immune response against VHSV that is followed by long-term adaptive immunity in VHS-vaccinated trout (Lorenzen et al. 2002).

  11. Dynamics and effects of Ligula intestinalis (L.) infection in the native fish Barbus callensis Valenciennes, 1842 in Algeria.

    PubMed

    Rouis, Sonia Ould; Rouis, Abdelhalim Ould; Dumont, Henri J; Magellan, Kit; Arab, Abdeslem

    2016-03-01

    The dynamics of the emergence, duration, and decline phases in epizootic cycles are well known for humans and some crops, but they are poorly understood for host-parasite systems in the wild. Parasites may be particularly insidious as they are often introduced unintentionally, simultaneously with their hosts, and later transferred to species in the new location. Here we investigate the epizootic dynamics of the tapeworm Ligula intestinalis in the Hamiz reservoir, Algeria, and explore its effects on the cyprinid fish Barbus callensis. Regular sampling was conducted from October 2005 to February 2008 with intermittent surveys carried out until 2010. Five percent of the 566 specimens of B. callensis that were caught were infected, with the maximum number of parasites found in spring. There was no obvious difference in weight between uninfected fish and infected ones, and infection did not affect fish condition. However, infected fish were significantly longer than uninfected fish and had inhibited gonad development. The proportion of infected fish caught was significantly higher in year 1 and by the second winter, infection collapsed to zero. The Ligula infection thus appeared to have minimal ecological effects and be of a temporary nature, thus exhibiting an epizootic cycle. Taken together, our data indicates that this infection declined or even failed during our study period. Failure may be due to the specific genetic strain of Ligula, but invasive carp may also have been influential in both the introduction and subsequent decline of this parasite.

  12. Morphological, cytochemical, and ultrastructural study of thrombocytes and leukocytes in neotropical fish, Brycon orbignyanus Valenciennes, 1850 (Characidae, Bryconinae).

    PubMed

    Tavares-Dias, M; Moraes, F R

    2006-01-01

    Morphological, cytochemical and ultrastructural studies are important to demonstrate the function of the blood cells, which is very little understood in teleosts. In peripheral blood of 'piracanjuba' Brycon orbignyanus, thrombocytes, lymphocytes, monocytes, neutrophils and heterophils were studied and characterized. Thrombocytes had a fusiform or oval shape with PAS-positive granules. Lymphocytes presented small size with sparse basophilic cytoplasm. Monocytes were large in size, presented basophilic cytoplasm that may be foamy or vacuolated, with non-specific esterase staining. The neutrophils presented lightly neutrophilic granule cytoplasm, with positivity for PAS and peroxidase. The heterophils were large in size, with eosinophilic and basophilic granules cytoplasm and PAS-positive. Transmission electron microscopy study demonstrated that the thrombocytes, lymphocytes and monocytes features were similar to other teleosts. In ultrastructural study only one type of neutrophils was observed. Cytochemical findings indicated that neutrophils and monocytes of B. orbignyanus may be involved in phagocytosis, and neutrophils play an important microbicidal role.

  13. A preliminary study on Oxya fuscovittata (Marschall) as an alternative nutrient supplement in the diets of Poecillia sphenops (Valenciennes).

    PubMed

    Ganguly, Arijit; Chakravorty, Ranita; Sarkar, Angshuman; Mandal, Dipak K; Haldar, Parimalendu; Ramos-Elorduy, Julieta; Moreno, Jose Manuel Pino

    2014-01-01

    Growth of the ornamental fish industry is being hindered by the scarcity of low cost feed; hence alternative protein supplements should be explored. In this context the present study aims to evaluate whether the grasshopper Oxya fuscovittata could be used as a supplement for fish meal in the diets of Poecillia sphenops, which is one of the most common ornamental fishes worldwide. The present work is divided into three phases: In the first phase proximate composition of the grasshopper is obtained and five diets are prepared where fish meal is gradually replaced by Oxya meal and named as control, D1, D2, D3 and D4. All the diets are formulated on iso-nitrogenous basis where the protein percentage is fixed at 400 g/kg. The second phase deals with feeding trial and in the third phase all the data of the feeding trial are subjected to a linear model. The feeding trial shows that the control, D1 and D2 fed fishes have almost similar results. The linear model proves that the variation in the indices are mainly due to replacement of fish meal by Oxya meal, not due to the variations of rice husk and mustard oil cake that are also used to formulate the diets of the present study. From the results two Oxya supplemented diets, i.e. D1 and D2 are proved to be almost equivalent to the control diet. Hence it is concluded that Oxya meal is able to replace 25% to 50% of fish meal from the diets of P. sphenops.

  14. [Composition and content of carotenoids in body of the Black Sea gastropod mollusc Rapana venosa (Valenciennes, 1846)].

    PubMed

    Borodina, A V; Maoka, T; Soldatov, A A

    2013-01-01

    There were studied content and composition of carotenoids in body of the Black Sea gastropod mollusc Rapana venosa. To separate and identify this group of compounds, methods of thin layer and high performance liquid chromatography, mass-spectra and spectra in UV-VIS range were used. There were identified 84-87% of carotenoids. The main proportion belonged to mytiloxanthine--28-30%. The rest--pectenolon, diatoxanthin, alloxanthin--accounted for 10-15% of the total content except for beta-carotene--3-4%. The fraction is also isolated which contains complex esters of pectenolon, diatoxanthin, alloxanthin, and mytiloxanthin. It amounts to 17-20 % of pigments of carotenoid line. Minor components were not determined. Pathways of metabolic transformation of carotenoids in tissues of R. venosa are considered on the basis of study of the trophic system "mollusc-filtrator--mollusc-predator" by the example of Mytilus galloprovincialis and R. venosa.

  15. A description on pharyngeal jaw apparatus and diets of halfbeak fish Zenarchopterus buffonis (Valenciennes 1847) in Malaysian waters

    SciTech Connect

    Abidin, Diana Atiqah Zainal Hashim, Marina; Ghaffar, Mazlan Abd.; Das, Simon K.

    2015-09-25

    Information on the feeding mechanism and diet of halfbeak fish species in harsh estuarine environment ecosystem is still lacking. The present study investigates the fine structure of pharyngeal jaw apparatus and diets of halfbeak fish Zenarchopterus buffonis. A total of 84 halfbeak fish samples have been collected from the coastal water of Peninsular Malaysia using fishing rod. Scanning electron microscopy was used to examine the micrographs of fine microstructure of the pharyngeal teeth. The fundamental anatomy of pharyngeal jaw apparatus displayed that the upper pharyngeal jaw (third pharyngobranchials) displays larger size of hook-like or tricuspid teeth which was analogous to tricuspid morphology. The lower pharyngeal jaw (fifth ceratobranchial) bears mainly conical teeth and appears triangular shape with two, short projections. The estimated TROPH values (1 − 3.2±0.55) denoted that halfbeak fish were omnivores in nature. The findings of this study was found to be useful as a baseline information for a better representation of the trophic flows associated with large medium and small surface water fishes.

  16. Preliminary Assessment on Autecological Studies of Beardless Barb, Cyclocheilichthys apogon (Valenciennes, 1842) from Muda Reservoir of Kedah, Malaysia

    PubMed Central

    Rosli, Nor Aziella Mohd; Zain, Khaironizam Md

    2016-01-01

    Like many other countries, reservoirs in Malaysia are primarily built for various functions such as hydroelectric power generation, drinking water supply, flood mitigation and irrigation for agricultural purposes. Artisanal fisheries activities were also performed in these reservoirs. The freshwater fish are a requisite source of protein for the rural population. Consequently, the fish resources in reservoirs should be carefully maintained at sustainable level. Present study elucidates the preliminary assessment on autecological studies of beardless barb, Cyclocheilichthys apogon as a model of fish biota in Muda Reservoir. This research investigates the growth pattern of C. apogon using length-weight relationship and their condition factor. A total of 307 specimens were captured using cast net for six consecutive months from March 2014 until August 2014. The growth coefficient (b) from the length-weight equation (W = aLb) for male and female of C. apogon were 3.150 and 3.185, respectively, indicating positive allometric growth. The condition factor values of male and female of C. apogon were 1.023 ± 0.111 and 1.026 ± 0.100, respectively, suggesting that C. apogon is in good condition in Muda Reservoir. The paucity of research on the autecological study in the Muda Reservoir contributes to the main reason of performing this research. The findings will serve as baseline information of this species in Muda Reservoir, as well as for comparative study in the future. PMID:27965742

  17. A Preliminary Study on Oxya fuscovittata (Marschall) as an Alternative Nutrient Supplement in the Diets of Poecillia sphenops (Valenciennes)

    PubMed Central

    Ganguly, Arijit; Chakravorty, Ranita; Sarkar, Angshuman; Mandal, Dipak K.; Haldar, Parimalendu; Ramos-Elorduy, Julieta; Moreno, Jose Manuel Pino

    2014-01-01

    Growth of the ornamental fish industry is being hindered by the scarcity of low cost feed; hence alternative protein supplements should be explored. In this context the present study aims to evaluate whether the grasshopper Oxya fuscovittata could be used as a supplement for fish meal in the diets of Poecillia sphenops, which is one of the most common ornamental fishes worldwide. The present work is divided into three phases: In the first phase proximate composition of the grasshopper is obtained and five diets are prepared where fish meal is gradually replaced by Oxya meal and named as control, D1, D2, D3 and D4. All the diets are formulated on iso-nitrogenous basis where the protein percentage is fixed at 400 g/kg. The second phase deals with feeding trial and in the third phase all the data of the feeding trial are subjected to a linear model. The feeding trial shows that the control, D1 and D2 fed fishes have almost similar results. The linear model proves that the variation in the indices are mainly due to replacement of fish meal by Oxya meal, not due to the variations of rice husk and mustard oil cake that are also used to formulate the diets of the present study. From the results two Oxya supplemented diets, i.e. D1 and D2 are proved to be almost equivalent to the control diet. Hence it is concluded that Oxya meal is able to replace 25% to 50% of fish meal from the diets of P. sphenops. PMID:25383946

  18. Species of Haliotrema Johnston & Tiegs, 1922 (Monogenea: Dactylogyridae) from Zanclus cornutus (L.) (Teleostei: Zanclidae) and Acanthurus nigrofuscus (Forsskål) (Teleostei: Acanthuridae) in the South China Sea.

    PubMed

    Sun, Yuan; Gibson, David I; Yang, Tingbao

    2011-07-01

    Four species of Haliotrema Johnston & Tiegs, 1922, including three new taxa, are described from the gills of two species of coral reef fishes, Zanclus cornutus (Linnaeus) and Acanthurus nigrofuscus (Forsskål), off the Dongsha Islands in the South China Sea. Haliotrema dongshaense n. sp., from Z. cornutus, is differentiated from other existing congeneric species by its peculiar male copulatory organ, comprising a harp-shaped copulatory tube and a cup-shaped base, and two groups of short longitudinal muscles lying on either side of the vaginal vestibule. Haliotrema zigmoidocirrus n. sp. from Z. cornutus and H. nigrofusci n. sp. from A. nigrofuscus are differentiated from other congeneric species by their male copulatory organ, which has a cup-shaped base, bell-shaped middle and Z-shaped distal part, and the latter can be readily differentiated from the former by its distinctively wider haptor and longer connecting bars. Haliotrema sicklocirrus Wang, 2007, from Z. cornutus, is redescribed with additional details, including the sinistral position of the accessory piece of the male copulatory organ, the absence of eyespots and the morphology of the connecting bars.

  19. Viral replication in excised fin tissues (VREFT) corresponds with prior exposure of Pacific herring, Clupea pallasii (Valenciennes), to viral haemorrhagic septicaemia virus (VHSV).

    PubMed

    Grady, C A; Gregg, J L; Wade, R M; Winton, J R; Hershberger, P K

    2011-01-01

    Procedures for a viral replication in excised fin tissue (VREFT) assay were adapted to Pacific herring, Clupea pallasii, and optimized both to reduce processing time and to provide the greatest resolution between naïve herring and those previously exposed to viral haemorrhagic septicaemia virus (VHSV), Genogroup IVa. The optimized procedures included removal of the left pectoral fin from a euthanized fish, inoculation of the fin with >10(5) plaque-forming units (PFU) mL(-1) VHSV for 1 h, rinsing the fin in fresh medium six times to remove unadsorbed virions, incubation of the fin in fresh medium for 4 days and enumeration of the viral titre in a sample of the incubation medium by plaque assay. The optimized VREFT assay was effective at identifying the prior exposure history of laboratory-reared Pacific herring to VHSV. The geometric mean VREFT value was significantly greater (P < 0.01) among naïve herring (1.2 × 10(3) PFU mL(-1) ) than among groups that survived exposure to VHSV (1.0-2.9 × 10(2) PFU mL(-1) ); additionally, the proportion of cultures with no detectable virus was significantly greater (P = 0.0002) among fish that survived exposure to VHSV (39-47%) than among naïve fish (3.3%). The optimized VREFT assay demonstrates promise for identifying VHSV exposure history and forecasting disease potential in populations of wild Pacific herring.

  20. Genetic Structure and Preliminary Findings of Cryptic Diversity of the Malaysian Mahseer (Tor tambroides Valenciennes: Cyprinidae) Inferred from Mitochondrial DNA and Microsatellite Analyses

    PubMed Central

    Abdul Rahim, Khairul Adha

    2013-01-01

    This study examines the population genetic structure of Tor tambroides, an important freshwater fish species in Malaysia, using fifteen polymorphic microsatellite loci and sequencing of 464 base pairs of the mitochondrial cytochrome c oxidase I (COI) gene. A total of 152 mahseer samples were collected from eight populations throughout the Malaysia river system. Microsatellites results found high levels of intrapopulation variations, but mitochondrial COI results found high levels of interpopulations differentiation. The possible reasons for their discrepancies might be the varying influence of genetic drift on each marker or the small sample sizes used in most of the populations. The Kelantan population showed very low levels of genetic variations using both mitochondrial and microsatellite analyses. Phylogenetic analysis of the COI gene found a unique haplotype (ER8∗), possibly representing a cryptic lineage of T. douronensis, from the Endau-Rompin population. Nevertheless, the inclusion of nuclear microsatellite analyses could not fully resolve the genetic identity of haplotype ER8∗ in the present study. Overall, the findings showed a serious need for more comprehensive and larger scale samplings, especially in remote river systems, in combination with molecular analyses using multiple markers, in order to discover more cryptic lineages or undescribed “genetic species” of mahseer. PMID:24455674

  1. Histopathological and bacterial study of skin and gill of grass carp, Ceteopharyngodon idella, (Valenciennes 1844) exposed to copper sulfate and potassium permanganate.

    PubMed

    Jooyandeh, Fatemeh; Sadeghpour, Ali; Khara, Hossein; Pajand, Zabihollah

    2016-09-01

    The gill histology and bacterial load of skin of the grass carp juveniles were investigated in relation to various concentrations of copper sulfate and potassium permanganate. For this purpose, the sublethal doses were determined after a pre-test and then the experiment was done in five treatments (for copper sulfate: 1, 1.94, 3.71, 7.07 and 15 mg/l and for potassium permanganate: 0.25, 0.52, 1.91, 2.27 and 5 mg/l) with three replicates inside the glass aquaria. Also, one group without disinfecting product was considered as control for each experiment. The microbial and histopathological investigations were done after 96 h exposure. According to results, the lowest bacterial load (CFU/g) of skin was observed in 15 mg/l copper sulfate treatment and 0.25 mg/l potassium permanganate treatment (P < 0.05). Also, the histological investigation showed a range of histopathological alternations in gills tissue including lamellar necrosis, hyperplasia, lamellar adhesion, haemorrhage, clubbing of gill lamellae. The severity of these alternations increased with increasing of the doses of the copper sulfate and potassium permanganate. In this regard, the highest histological damages were observed in 15 mg/l copper sulfate and 5 mg/l potassium permanganate respectively. Our results showed that low dosage of potassium permanganate has best effect on reducing of bacterial load of skin with lowest adverse effects on gill tissue.

  2. Larval Pacific herring, Clupea pallasii (Valenciennes), are highly susceptible to viral haemorrhagic septicaemia and survivors are partially protected after their metamorphosis to juveniles

    USGS Publications Warehouse

    Hershberger, P.K.; Gregg, J.; Pacheco, C.; Winton, J.; Richard, J.; Traxler, G.

    2007-01-01

    Pacific herring were susceptible to waterborne challenge with viral haemorrhagic septicaemia virus (VHSV) throughout their early life history stages, with significantly greater cumulative mortalities occurring among VHSV-exposed groups of 9-, 44-, 54- and 76-day-old larvae than among respective control groups. Similarly, among 89-day-1-year-old and 1+year old post-metamorphosed juveniles, cumulative mortality was significantly greater in VHSV-challenged groups than in respective control groups. Larval exposure to VHSV conferred partial protection to the survivors after their metamorphosis to juveniles as shown by significantly less cumulative mortalities among juvenile groups that survived a VHS epidemic as larvae than among groups that were previously nai??ve to VHSV. Magnitude of the protection, measured as relative per cent survival, was a direct function of larval age at first exposure and was probably a reflection of gradual developmental onset of immunocompetence. These results indicate the potential for easily overlooked VHS epizootics among wild larvae in regions where the virus is endemic and emphasize the importance of early life history stages of marine fish in influencing the ecological disease processes. ?? 2007 The Authors.

  3. Viral replication in excised fin tissues (VREFT) corresponds with prior exposure of Pacific herring, Clupea pallasii (Valenciennes), to viral haemorrhagic septicaemia virus (VHSV)

    USGS Publications Warehouse

    Grady, C.A.; Gregg, J.L.; Wade, R.M.; Winton, J.R.; Hershberger, P.K.

    2011-01-01

    Procedures for a viral replication in excised fin tissue (VREFT) assay were adapted to Pacific herring, Clupea pallasii, and optimized both to reduce processing time and to provide the greatest resolution between na??ve herring and those previously exposed to viral haemorrhagic septicaemia virus (VHSV), Genogroup IVa. The optimized procedures included removal of the left pectoral fin from a euthanized fish, inoculation of the fin with >105 plaque-forming units (PFU) mL-1 VHSV for 1 h, rinsing the fin in fresh medium six times to remove unadsorbed virions, incubation of the fin in fresh medium for 4 days and enumeration of the viral titre in a sample of the incubation medium by plaque assay. The optimized VREFT assay was effective at identifying the prior exposure history of laboratory-reared Pacific herring to VHSV. The geometric mean VREFT value was significantly greater (P < 0.01) among na??ve herring (1.2 ?? 103 PFU mL-1) than among groups that survived exposure to VHSV (1.0-2.9 ?? 102 PFU mL-1); additionally, the proportion of cultures with no detectable virus was significantly greater (P = 0.0002) among fish that survived exposure to VHSV (39-47%) than among na??ve fish (3.3%). The optimized VREFT assay demonstrates promise for identifying VHSV exposure history and forecasting disease potential in populations of wild Pacific herring. ?? 2010 Blackwell Publishing Ltd.

  4. Stress indices of Grass carp, Ceteopharyngodon idella, (Cuvier and Valenciennes, 1884) change in response to Monogenean parasites pollution, Gyrodactylus spp. and Dactylogyrus spp.

    PubMed

    Tekmedash, Fatemeh Shojaei; Hemmatzadeh, Mohtaram; Khara, Hossein

    2016-09-01

    The aim of this research was study of stress indices in response to Monogenean infection in Grass carp, Ceteopharyngodon idella. In this regard, some stress indices were measured in two adult groups of Grass carp including healthy and infected fish. According to our results, the values of cortisol and glucose and lactate were significantly higher in infected fishes than healthy individuals. Elevation of cortisol and glucose demonstrated the existence of stressful condition caused by parasitic infection and demands for energy for adaptation. In conclusion, our results showed that Monogenean infection by Gyrodactylus spp. and Dactylogyrus spp. affects health condition of Grass carp through alternation of stress components.

  5. Capoeta damascina (Valenciennes, 1842), a new host of Contracaecum sp. and Capillaria sp. (Nematoda) from the Kor River Basin, southwestern Iran

    PubMed Central

    Gholami, Zeinab; Rahimi, Mohammad Taghi; Kia, Eshrat Beigom; Esmaeili, Hamid Reza; Mobedi, Iraj

    2014-01-01

    Objective To investigate the parasitic infection status of cyprinid fish, Capoeta damascina in Gomban spring-stream, Kor River Basin, Fars Province, southwestern Iran. Methods A total of 12 cyprinid fish (7 females and 5 males) were collected from Gomban spring-stream, Kor River Basin, Fars Province, southwestern Iran. The collected fish were dissected carefully and their internal organs such as liver, gonad, muscle, abdominal lobes, whole viscera and digestive tract were surveyed parasitologically. Results One female cyprinid fish out of 12 fish was infected with three nematodes. Two nematodes (larvae) were identified as Contracaecum sp. which were attached firmly to the outer part of intestine and another adult helminth was recognized as Capillaria sp. which was recovered from digestive content. Conclusions This study is the first record indicating that cyprinid fish acts as a new host for recovered nematodes. Further helminthological investigations are highly recommended in different parts of Iran in order to expand our knowledge about helmintic parasites of cyprinid fish and their role in transmission of diseases to human and animal. PMID:25183068

  6. Integrated biological control of water hyacinths, Eichhornia crassipes by a novel combination of grass carp, Ctenopharyngodon idella (Valenciennes, 1844), and the weevil, Neochetina spp.

    NASA Astrophysics Data System (ADS)

    Gopalakrishnan, Ayyaru; Rajkumar, Mayalagu; Sun, Jun; Parida, Ajay; Venmathi Maran, Balu Alagar

    2011-01-01

    The efficacy of grass carp Ctenopharyngodon idella (Cyprinidae) and weevils Neochetina spp. (Curculionidae) to control the aquatic weed, water hyacinth, is investigated in a square net cage (happas) setting at a farm in Cuddalore District, South India. This novel combination of insects and fish is found to be superior to individual treatments for controlling the weed growth within 110 d. The biomass of the weed, number of plants, percentage of flowered plants and chlorophyll contents were studied. The weed biomass is reduced from 5 kg (day 1) to 0.33 kg (day 110) when exposed to grass carp and weevils. The number of plants is reduced to 0.75 in grass carp and weevil exposed happas, while it is 741.5 in the control. The mean number of leaves per plant is also reduced. In addition, the chlorophyll a and b are significantly reduced in happas exposed to the combination of fish and insects when compared to the other treatments. Based on the results of this study, we consider the combined use of grass carp and weevils to be more efficient and sustainable for managing water hyacinths than the use of these organisms individually.

  7. A new cave-dwelling loach, Triplophysa xichouensis sp. nov. (Teleostei Nemacheilidae) from Yunnan, China.

    PubMed

    Liu, S W; Pan, X F; Yang, J X; Chen, X Y

    2017-03-01

    A new cave-dwelling loach of the genus Triplophysa, T. xichouensis, is described from an outlet of a subterranean river in Xisa Town, Xichou County, Yunnan Province, China. It can be distinguished from its congeners by the following characters: dorsal-fin rays iii, 8; anal-fin rays ii, 6; pectoral-fin rays i, 9 or 10; pelvic-fin rays i, 5 or 6; branched caudal-fin rays 16(8+8); eyes highly degenerated to a very tiny black dot; dorsal-fin origin closer to snout tip than to caudal-fin base and anterior to vertical line of pelvic-fin origin; pectoral fin length about two-thirds the distance between pectoral-fin origin to pelvic-fin origin; caudal peduncle slender, its length about three times its depth; caudal fin emarginate; body smooth and scaleless; lateral line complete and straight; anterior chamber of air bladder wrapped in dumbbell-shaped bony capsule and the posterior one well developed, long, oval; intestine short, bending in zigzag shape behind stomach. A key for the cave-dwelling species of Triplophysa is provided. urn:lsid:zoobank.org:pub:9162FFB1-7911-47C3-AE50-6A00E9590327.

  8. Multiple Invasions into Freshwater by Pufferfishes (Teleostei: Tetraodontidae): A Mitogenomic Perspective

    PubMed Central

    Yamanoue, Yusuke; Miya, Masaki; Doi, Hiroyuki; Mabuchi, Kohji; Sakai, Harumi; Nishida, Mutsumi

    2011-01-01

    Pufferfishes of the Family Tetraodontidae are the most speciose group in the Order Tetraodontiformes and mainly inhabit coastal waters along continents. Although no members of other tetraodontiform families have fully discarded their marine lives, approximately 30 tetraodontid species spend their entire lives in freshwaters in disjunct tropical regions of South America, Central Africa, and Southeast Asia. To investigate the interrelationships of tetraodontid pufferfishes and thereby elucidate the evolutionary origins of their freshwater habitats, we performed phylogenetic analysis based on whole mitochondrial genome sequences from 50 tetraodontid species and closely related species (including 31 newly determined sequences). The resulting phylogenies reveal that the family is composed of four major lineages and that freshwater species from the different continents are independently nested in two of the four lineages. A monophyletic origin of the use of freshwater habitats was statistically rejected, and ancestral habitat reconstruction on the resulting tree demonstrates that tetraodontids independently entered freshwater habitats in different continents at least three times. Relaxed molecular-clock Bayesian divergence time estimation suggests that the timing of these invasions differs between continents, occurring at 0–10 million years ago (MA) in South America, 17–38 MA in Central Africa, and 48–78 MA in Southeast Asia. These timings are congruent with geological events that could facilitate adaptation to freshwater habitats in each continent. PMID:21364898

  9. Ontogeny, variation, and homology in Salvelinus alpinus caudal skeleton (Teleostei: Salmonidae).

    PubMed

    Grünbaum, Thomas; Cloutier, Richard

    2010-01-01

    The ontogeny of the caudal skeleton in the Arctic charr, Salvelinus alpinus was examined using an extensive series of cleared and stained specimens. We demonstrate the presence of skeletal components never reported previously within the Salmonidae. In contrast to the generalized condition for salmonids, seven hypurals (instead of six), and four uroneurals (instead of three) have been found in some specimens. Variation in the number and condition of epurals is documented. New hypotheses are proposed concerning (1) relationships among centra and their associated elements, (2) phylogenetic distribution of caudal characters within the Salmonidae, and (3) homology of caudal components. Using the published phylogenetic hypotheses, we provide evidence, that a seventh hypural and a fourth uroneural are taxic atavism in salmonids. The development of the salmonid homocercal fin is discussed in the light of a polyural scheme based on evidences of a one-to-one relationship among ural centra and their associated elements.

  10. Evolution and phylogenetic application of the MC1R gene in the Cobitoidea (Teleostei: Cypriniformes)

    PubMed Central

    TANG, Qiong-Ying; LIANG, Li-Xia; LIU, Fei; YU, Dan; LIU, Huan-Zhang

    2016-01-01

    Fish of the superfamily Cobitoidea sensu stricto (namely loaches) exhibit extremely high diversity of color patterns, but so far little is known about their evolutionary mechanism. Melanocortin 1 receptor gene (MC1R) plays an important role during the synthesis of melanin and formation of animal body color patterns. In this study, we amplified and sequenced the partial MC1R gene for 44 loach individuals representing 31 species of four families. Phylogenetic analyses yielded a topology congruent with previous studies using multiple nuclear loci, showing that each of the four families was monophyletic with sister relationships of Botiidae+ (Cobitidae+(Balitoridae+Nemacheilidae)). Gene evolutionary analyses indicated that MC1R in loaches was under purifying selection pressure, with various sites having different dN/dS values. Both Botiidae and Cobitidae had lower dN/dS values than those of background lineages, suggesting their evolution might be strongly affected by purifying selection pressure. For Balitoridae and Nemacheilidae, both had larger dN/dS values than those of background lineages, suggesting they had a faster evolutionary rate under more relaxed selection pressure. Consequently, we inferred that the relatively stable color patterns in Botiidae and Cobitidae might result from the strong purifying selection pressure on the MC1R gene, whereas the complicated and diverse color patterns in Balitoridae and Nemacheilidae might be associated with the relaxed selection pressure. Given the easy experimental procedure for the partial MC1R gene and its excellent performance in reconstructing phylogeny, we suggest this gene could be used as a good molecular marker for the phylogenetic study of fish species. PMID:27686787

  11. Huangshan population of Chinese Zacco platypus (Teleostei, Cyprinidae) harbors diverse matrilines and high genetic diversity.

    PubMed

    Zheng, Xin; Zhou, Tian-Qi; Wan, Tao; Perdices, Anabel; Yang, Jin-Quan; Tang, Xin-Sheng; Wang, Zheng-Ping; Huang, Li-Qun; Huang, Song; He, Shun-Ping

    2016-03-18

    Six main mitochondrial DNA (mtDNA) lineages have been described in minnow (Zacco platypus) samples obtained from northern, western and southern China. Perdices et al. (2004) predicted that further sampling of other tributaries might discover more lineages of this species. In this study, we collected 26 Zacco platypus individuals in the Huangshan area of eastern China and determined the cytochrome b (cytb) sequence variations. Combined with reported data in GenBank, we identified ten matrilines (Zacco A-J) in a total of 169 samples, with relatively high molecular divergence found among them. The Huangshan population had the greatest genetic variation among all sampled regions and hosted six of the ten matrilines. Our results highlight the significance of the Huangshan area for the conservation of Zacco platypus.

  12. Aspidoras mephisto, new species: The first troglobitic Callichthyidae (Teleostei: Siluriformes) from South America.

    PubMed

    Tencatt, Luiz Fernando Caserta; Bichuette, Maria Elina

    2017-01-01

    Aspidoras mephisto n. sp. is described from the Anésio-Russão cave system, upper Tocantins River basin, Goiás, Brazil. The species can be readily distinguished from its congeners by troglomorphic features and also by presenting the following combination of features: infraorbital 1 generally with well-developed ventral laminar; or moderately developed; poorly-developed serrations on posterior margin of pectoral spine; nuchal plate not externally visible; dorsal fin, even in conspicuously colored specimens, with only dark brown or black chromatophores concentrated on rays, forming spots in some specimens; membranes hyaline; or sparse dark brown or black chromatophores on membranes, not forming any conspicuous pattern; and inner laminar expansion of infraorbital 1 moderately developed. Information about its habitat, ecology, behaviour and conservation status are provided and also a brief description of the juvenile stage.

  13. A new redfin species, Pseudobarbus skeltoni (Cyprinidae, Teleostei), from the Cape Floristic Region, South Africa.

    PubMed

    Chakona, Albert; Swartz, Ernst R

    2013-01-01

    A new cyprinid species, Pseudobarbus skeltoni sp. nov, is described from material recently collected in the upper Riviersonderend River (a major tributary of the Breede River system) and the Krom River (a tributary of the Molenaars River in the upper Breede River) in the Cape Floristic Region of South Africa. The new species is readily distinguished from congeners, except P. burgi and P burchelli, by having two pairs of prominent oral barbels. Pseudobarbus skeltoni can be distinguished from P. burgi and P burchelli by the following combination of characters: distinctive terminal (vs. subterminal) mouth in adults; mouth inferior in sub-adults and young adults of P skeltoni but lower lips are unretracted (vs. retracted) and lack a distinct cartilaginous plate; snout prominent; more slender head (head depth 64.2% of HL, vs. 70.1% of HL in P. burchelli and 74.1% of HL in P. burgi); and a longer head relative to standard length (30.5 % vs. 26.8% in P. burchelli and 25.8% in P. burgi). The new species attains the largest size of any Pseudobarbus. The restricted distribution and the small remaining population sizes of P skeltoni indicate that this species is highly threatened and requires immediate conservation attention.

  14. Haematological parameters in Umbrina cirrosa (Teleostei, Sciaenidae): a comparison between diploid and triploid specimens.

    PubMed

    Ballarin, Loriano; Dall'Oro, Manuela; Bertotto, Daniela; Libertini, Angelo; Francescon, Antonia; Barbaro, Alvise

    2004-05-01

    Haematological features were compared between diploid and triploid specimens of the ray-finned fish Umbrina cirrosa. No significant differences between diploids and triploids were reported in haematocrit and total haemoglobin concentration, but erythrocytes and thrombocytes were significantly greater in size in triploids. Glycaemia was significantly lower in diploids, whereas triploid erythrocytes were more resistant to osmotic stress. In triploids, a greater fraction of leukocytes was positive for alkaline phosphatase activity, when stimulated with Bacillus clausii spores, otherwise no significant increase of oxygen consumption was observed in triploid leukocytes after stimulation, based on assays for superoxide anions. Triploids were characterized by a lower concentration of circulating blood cells with a lower surface/volume ratio when compared with diploids. These features may lead to a general disadvantage of triploids in withstanding stress conditions: a situation that needs to be taken into account in aquaculture practice.

  15. Sensitivity of Danio rerio (Teleostei, Cyprinidae) during two stages of development based on acute toxicity tests.

    PubMed

    Freiry, R; Stelzer, J A A; Maltchik, L; Arenzon, A

    2014-10-01

    The sensitivity of Danio rerio to three chemicals was compared at two growth stages [larval (10 ± 2 after hatching) and post-larval (60 ± 4 days after hatching)] based on acute toxicity tests. Thirty-nine 48 h acute toxicity tests were performed with the substances CuSO4, NaCl and KCl. The 48 h LC50 values at the two growth stages were compared by independent samples t-tests. The results showed a clear decrease in sensitivity when post-larval organisms were used. Since acute toxicity test methods for D. rerio that recommend using post-larval stage fish do not represent the most sensitive stage of the test organism, our study suggests a revision of the methods to use larval fish.

  16. Sequence analyses and chromosomal distribution of the Tc1/Mariner element in Parodontidae fish (Teleostei: Characiformes).

    PubMed

    Schemberger, Michelle Orane; Nogaroto, Viviane; Almeida, Mara Cristina; Artoni, Roberto Ferreira; Valente, Guilherme Targino; Martins, Cesar; Moreira-Filho, Orlando; Cestari, Marta Margarete; Vicari, Marcelo Ricardo

    2016-11-30

    Transposable elements are able to move along eukaryotic genomes. They are divided into two classes according to their transposition intermediate: RNA (class I or retrotransposons) or DNA (class II or DNA transposons). Most of these sequences are inactive or non-autonomous in eukaryotic genomes. Inactivate transposons can accumulate mutations at neutral rates until losing their molecular identity. They may either be eliminated from the genome or take on different molecular functions. Transposable elements may also participate in the differentiation of sex chromosomes. Therefore, the structural variations and nucleotide similarity of Tc1/Mariner sequences were analyzed along with their potential participation in the differentiation processes of sex chromosomes in the genomes of Parodontidae fish. All Parodontidae species presented non-autonomous copies of Tc1/Mariner with structural variation, different levels of deterioration (genetic distance), and variations in insertion and deletion patterns. The physical mapping of Tc1/Mariner on chromosomes revealed dispersed signals in euchromatins, with small accumulations in terminal regions and in the sex chromosomes. The gene dosage ratios indicated copy number variations of Tc1/Mariner among the genomes and high transposase open reading frame deterioration in Parodon hilarii and Parodon pongoensis genomes. This transposon presented transcriptional activity in gonads, but there was no significant difference between sexes. This may indicate non-functional protein expression or may correspond to DNA binding proteins derived from Tc1/Mariner. Thus, our results show Tc1/Mariner inactivation along with a diversity in Parodontidae genomes and its participation in the differentiation of the W sex chromosome.

  17. Mixed mesodermal and mesenchymal origin of myotomal muscles in pike (Esox lucius: Teleostei).

    PubMed

    Kacperczyk, A; Daczewska, M

    2006-02-01

    During the myotomal myogenesis in pike (Esox lucius) two phases of muscle differentiation can be distinguished. In the first phase, the somite cells-derived stock, the primary myoblasts (of mesodermal origin), fuse to form multinucleate myotubes. Participation of myotomal cells of mesodermal origin is insufficient for further muscle development. In the second stage mesenchymal cells migrate, via myosepts, into the myotome between myotubes. Immunocytochemical detection of proliferating cell nuclear antigen (marker of S phase of cell cycle) showed their mitotic activity. Transmission electron microscope analysis revealed that the differentiation of these cells depends on their position. Cells remaining in the myosepts develop into fibroblasts and produce collagen fibres, while those that have migrated into the myotomes transform into secondary myoblasts. Mesenchymal cells in the studied species are believed to participate in hypertrophy and hyperplasy of muscle fibres. Thus the muscle fibres in pike (E. lucius) are of mesodermal-mesenchymal origin.

  18. Liver transcriptome characterization of the endangered freshwater silverside Basilichthys microlepidotus (Teleostei: Atherinopsidae) using next generation sequencing.

    PubMed

    Vega-Retter, Caren; Véliz, David

    2014-10-25

    Twenty eight out of 44 Chilean freshwater fishes have been considered to fall within the vulnerable or threatened category. Thus, information about the biology, ecology and the effects of the anthropic activity on these species is fundamental to take appropriate conservation measures. In Chile the endemic silverside Basilichthys microlepidotus inhabits mainly rivers surrounded by cities; during the last 10years it was categorized as an endangered species, thus more basic information is needed in order to elaborate a plan of protection for this species. To this end, the transcriptome of B. microlepidotus was sequenced, assembled and characterized. A total of 7.8 million reads (1.05Gb) were obtained from the sequencing and 5.93 million reads (0.83Gb) were used for the de novo assembly, obtaining a total of 31,523 contigs. Of these, 13,724 contigs with expression in all the individuals used were retained for the functional annotation. 7938 sequences were successfully annotated; the biological processes class was the most highly represented, followed by molecular function and cellular component. These sequence data provide a useful new molecular resource for future studies on gene expression and the effects of the human activity on B. microlepidotus, which will facilitate obtaining more information about that, as well as the developing of appropriate conservation strategies for this species.

  19. Schindleria elongata, a new species of paedomorphic gobioid from the Red Sea (Teleostei: Schindleriidae).

    PubMed

    Fricke, R; Abu El-Regal, M

    2017-02-14

    A new species of paedomorphic gobioid, Schindleria elongata, from the Red Sea, is described on the basis of five specimens. The new species is characterized by its lack of body pigmentation; the body depth at pectoral-fin origin 4-5% of standard length (LS ) and at anal-fin origin 5-7% LS ; the predorsal length 66-70% LS ; pre-anal length 66-71% LS ; dorsal-fin rays 13 or 14; anal-fin rays 10 or 11; first dorsal-fin ray at myomere 20 or 21; first anal-fin ray below second to fourth dorsal-fin rays; myomeres 19 or 20 + 13 or 14 = 33 or 34 total; premaxillae and dentaries with small teeth; gas bladder located posteriorly at 56-60% LS ; males with a rod-like, flexible urogenital papilla lacking lobes, projections or accessory papillae, with distal half tapering to a broad, angular point and usually posteriorly directed. A key to the species of Schindleriidae is presented.

  20. Profundulus kreiseri, a new species of Profundulidae (Teleostei, Cyprinodontiformes) from northwestern Honduras

    PubMed Central

    Matamoros, Wilfredo A.; Schaefer, Jacob F.; Hernández, Carmen L.; Prosanta Chakrabarty

    2012-01-01

    Abstract A new species of Profundulus, Profundulus kreiseri (Cyprinodontiformes: Profundulidae), is described from the Chamelecón and Ulúa Rivers in the northwestern Honduran highlands. Based on a phylogenetic analysis using cytochrome b and the presence of synapomorphic characters (dark humeral spot, a scaled preorbital region and between 32-34 vertebrae), this new species is placed in the subgenus Profundulus, which also includes Profundulus (Profundulus) oaxacae, Profundulus (Profundulus) punctatus and Profundulus (Profundulus) guatemalensis. Profundulus kreiseri can be distinguished from other members of the subgenus Profundulus by having less than half of its caudal fin densely scaled. Profundulus kreiseri can further be differentiated from Profundulus (Profundulus) oaxacae and Profundulus (Profundulus) punctatus by the absence of rows of dark spots on its flanks. The new species can further be differentiated from Profundulus (Profundulus) guatemalensis by the presence of fewer caudal- and pectoral-fin rays. The new species is distinguished from congeners of the profundulid subgenus Tlaloc (viz., Profundulus (Tlaloc) hildebrandi, Profundulus (Tlaloc) labialis, Profundulus (Tlaloc) candalarius and Profundulus (Tlaloc) portillorum) by having a scaled preorbital region and a dark humeral spot. Profundulus kreiseri and Profundulus portillorum are the only two species of Profundulus that are endemic to the region south of the Motagua River drainage in southern Guatemala and northwestern Honduras. PMID:23166464

  1. Multi-locus fossil-calibrated phylogeny of Atheriniformes (Teleostei, Ovalentaria).

    PubMed

    Campanella, Daniela; Hughes, Lily C; Unmack, Peter J; Bloom, Devin D; Piller, Kyle R; Ortí, Guillermo

    2015-05-01

    Phylogenetic relationships among families within the order Atheriniformes have been difficult to resolve on the basis of morphological evidence. Molecular studies so far have been fragmentary and based on a small number taxa and loci. In this study, we provide a new phylogenetic hypothesis based on sequence data collected for eight molecular markers for a representative sample of 103 atheriniform species, covering 2/3 of the genera in this order. The phylogeny is calibrated with six carefully chosen fossil taxa to provide an explicit timeframe for the diversification of this group. Our results support the subdivision of Atheriniformes into two suborders (Atherinopsoidei and Atherinoidei), the nesting of Notocheirinae within Atherinopsidae, and the monophyly of tribe Menidiini, among others. We propose taxonomic changes for Atherinopsoidei, but a few weakly supported nodes in our phylogeny suggests that further study is necessary to support a revised taxonomy of Atherinoidei. The time-calibrated phylogeny was used to infer ancestral habitat reconstructions to explain the current distribution of marine and freshwater taxa. Based on these results, the current distribution of Atheriniformes is likely due to widespread marine dispersal along the margins of continents, infrequent trans-oceanic dispersal, and repeated invasion of freshwater habitats. This conclusion is supported by post-Gondwanan divergence times among families within the order, and a high probability of a marine ancestral habitat.

  2. Phylogeny and biogeography of Triportheidae (Teleostei: Characiformes) based on molecular data.

    PubMed

    Mariguela, T C; Roxo, F F; Foresti, F; Oliveira, C

    2016-03-01

    Triportheidae represents a relatively small family of characiform fishes with highly modified morphology. The relationship among characiform families is still unclear, and a phylogenetic analysis for the family including a representative number of Triportheus species has never been performed. Here, we inferred a phylogeny for 19 of the 22 species recognized for this family and two possible new Triportheus species using two mitochondrial and three nuclear genes. Our results show that (1) Triportheidae is monophyletic and a sister group of the clade consisting of the families Bryconidae and Gasteropelecidae; (2) Triportheus is monophyletic, but some species need to be reviewed and described; (3) all genera in Triportheidae, except for Agoniates originated in the period between Early Oligocene and Early Miocene; and (4) speciation in Triportheidae coincides with important geological events in South America, reinforcing the importance of time-calibrated trees to study fish evolution.

  3. Multilocus resolution of Mugilidae phylogeny (Teleostei: Mugiliformes): Implications for the family's taxonomy.

    PubMed

    Xia, Rong; Durand, Jean-Dominique; Fu, Cuizhang

    2016-03-01

    The interrelationships among mugilids (Mugiliformes: Mugilidae) remain highly debated. Using a mitochondrial gene-based phylogeny as criterion, a revised classification with 25 genera in the Mugilidae has recently been proposed. However, phylogenetic relationships of major mitochondrial lineages remain unresolved and to gain a general acceptance the classification requires confirmation based on multilocus evidence and diagnostic morphological characters. Here, we construct a species-tree using twelve nuclear and three mitochondrial loci and infer the evolution of 71 morphological characters. Our multilocus phylogeny does not agree with previous morphology-based hypotheses for the relationships within Mugilidae, confirms the revised classification with 25 genera and further resolves their phylogenetic relationships. Using the well-resolved multilocus phylogeny as the criterion, we reclassify Mugilidae genera into three new subfamilies (Myxinae, Rhinomugilinae, and Cheloninae) and one new, recombined, subfamily (Mugilinae). The Rhinomugilinae subfamily is further divided into four tribes. The revised classification of Mugilidae is supported by morpho-anatomical synapomorphies or a combination of characters. These characters are used to erect a key to the subfamilies and genera.

  4. Two new species of the genus Cobitis Linnaeus (Teleostei: Cobitidae) from southern China

    NASA Astrophysics Data System (ADS)

    Chen, Yongxia; Sui, Xiaoyun; Liang, Na; Chen, Yifeng

    2016-05-01

    Two new species of the genus Cobitis from southern China, C. hereromacula from the Luohe River in Guangdong Province and C. baishagensis from the Nandujiang River in Hainan Province, are described and illustrated here. C. hereromacula can be distinguished from its congeners by possessing the following combination of characteristics: absence of the second and third pigmentary zones of Gambetta; 13-16 oval blotches on the dorsum and 10-13 vertical, elongated triangular blotches below the midlateral line with more than 20 vertical dark brown bars between them; 6-7 narrow rows of dark spots on the caudal fin; a vertical oval spot smaller than the eye diameter on the upper part of the caudal peduncle; pointed mental lobes of the lower lip pointed with a slightly filiform tip; one slender and long needle-shaped lamina circularis at the base of the first branched ray of the male pectoral fins. C. baishagensis can be distinguished from its congeners by the fourth Gambetta zone being covered by 10-12 transverse elongated blotches; 4-5 narrow rows of dark spots on the caudal fin; a vertical blotch smaller than the eye diameter on the upper part of the caudal peduncle; males with a slender and long needle-shaped lamina circularis at the second branched pectoral fin ray in males; large scales with a slightly large focal zone; undeveloped mental lobes with a lower lip that does not end posteriorly in a filiform tip.

  5. Redescription of Gobio nigrescens from the Hari River drainage (Teleostei: Cyprinidae).

    PubMed

    Mousavi-Sabet, Hamed; Ganjbakhsh, Babak; Geiger, Matthias F; Geiger, Matthias F; Freyhof, Jörg

    2016-05-20

    Gobio nigrescens, from the Hari River drainage, is redescribed. It represents a valid species distinguished from congeners in the adjacent Caspian and Aral Sea basins by a combination of characters: a naked breast, 16 circumpeduncular scales and 6-7 irregularly shaped, black or brown blotches on back behind dorsal-fin base.

  6. Sexual Ornaments, Body Morphology, and Swimming Performance in Naturally Hybridizing Swordtails (Teleostei: Xiphophorus)

    PubMed Central

    Johnson, James B.; Macedo, Danielle C.; Passow, Courtney N.; Rosenthal, Gil G.

    2014-01-01

    Determining the costs of sexual ornaments is complicated by the fact that ornaments are often integrated with other, non-sexual traits, making it difficult to dissect the effect of ornaments independent of other aspects of the phenotype. Hybridization can produce reduced phenotypic integration, allowing one to evaluate performance across a broad range of multivariate trait values. Here we assess the relationship between morphology and performance in the swordtails Xiphophorus malinche and X. birchmanni, two naturally-hybridizing fish species that differ extensively in non-sexual as well as sexual traits. We took advantage of novel trait variation in hybrids to determine if sexual ornaments incur a cost in terms of locomotor ability. For both fast-start and endurance swimming, hybrids performed at least as well as the two parental species. The sexually-dimorphic sword did not impair swimming performance per se. Rather, the sword negatively affected performance only when paired with a sub-optimal body shape. Studies seeking to quantify the costs of ornaments should consider that covariance with non-sexual traits may create the spurious appearance of costs. PMID:25329558

  7. Devario deruptotalea, a new species of cyprinid fish from Manipur, India (Teleostei: Cyprinidae).

    PubMed

    Ramananda, Yumnam; Vishwanath, Waikhom

    2014-07-02

    Devario deruptotalea, a new cyprinid fish, is described from Dutah Stream, a tributary of the Yu River (Chindwin drainage) in Manipur, India. It is distinguished from all its congeners by a unique colour pattern consisting of the following combination of pigmented elements: 4‒6 dark brown irregularly shaped and arranged bars that are partly confluent with adjacent bars at different levels on the anterior one-third of the side of the body, followed by three distinct dark brown stripes posteriorly, a P stripe that is darker and about twice as broad as other stripes and extending to the tip of the median caudal-fin rays.

  8. A new species of Psilorhynchus (Teleostei: Psilorhynchidae) from the Chindwin basin of Manipur, India.

    PubMed

    Shangningam, Bungdon; Vishwanath, Waikhom

    2013-01-01

    Psilorhynchus chakpiensis, new species, is described from the Chakpi River, Chindwin basin in Manipur, India. It is distinguished from its congeners by a combination of characters: a dome-shaped rostral cap with horizontally arranged pointed tubercles, 1-2 rows of prominent globular papillae behind the upper lip, three unbranched and nine branched dorsal-fin rays, 30-31 lateral-line scales, head width 74-83% HL, and characteristic colour bands on the dorsal and caudal fins. It is distinguished from all congeners in having a caudal-fin pattern consisting of two black bars, one incomplete bar near the base of the upper lobe, and a complete bar across the centre of the fin, traversing from the upper to the lower margin of the fin.

  9. Two new dwarfgobies (Teleostei: Gobiidae) from the Ryukyu Islands, Japan: Eviota flavipinnata and Eviota rubrimaculata.

    PubMed

    Suzuki, Toshiyuki; Greenfield, David W; Motomura, Hiroyuki

    2015-08-28

    Two new species of Eviota from Yoron Island, the Ryukyu Islands, Japan, are described. Both species belong to the cephalic sensory-canal pore system pattern 2 (lacking only the H [IT] pore); have some pectoral-fin rays branched; have a dorsal/anal-fin formula of 9/8; no dark spot over the ural centrum; no prominent distinct dark spots on the pectoral-fin base; no postocular spots; and no strong dark spots on the caudal fin. The species share the most characters with E. afelei, E. bimaculata and E. punctulata, but differ from Eviota afelei and E. punctulata by having two versus three dark marks over the anal-fin base, and from Eviota bimaculata by lacking the two dark, prominent occipital spots present in that species. Both species differ from all other described species of Eviota in fresh coloration. Eviota flavipinnata has bright golden-yellow dorsal fins and an orange anal fin, and a fifth pelvic-fin ray that is 12% the length of the fourth ray. Eviota rubrimaculata has clear dorsal fins with red spots, large red spots on the body, and lacks the fifth pelvic-fin ray.

  10. Two new dwarfgobies of the genus Eviota from the Ryukyu Islands, Japan (Teleostei: Gobiidae).

    PubMed

    Greenfield, David W; Suzuki, Toshiyuki; Shibukawa, Koichi

    2014-03-10

    Two species of dwarfgoby are described from the Ryukyu Islands, Japan. Eviota flebilis n. sp. belongs to cephalic sensory-pore system pattern 2 (lacking only IT pore), has a dorsal/anal fin-ray formula of 8/7, unbranched pectoral-fin rays, the 5th pelvic-fin ray 12.9% of the 4th, a distinctive narrow, red-orange line under the eye, and a dark vertical line at the caudal-fin base. Eviota specca n. sp. has a cephalic sensory-pore system pattern 1 (complete), has a dorsal/anal-fin formula of 8/8, the body heavily sprinkled with chromatophores, and a single dark spot on the upper pectoral-fin base.

  11. Site selection of Acanthochondria cornuta (Copepoda: Chondracanthidae) in Platichthys flesus (Teleostei: Pleuronectidae).

    PubMed

    Cavaleiro, F I; Santos, M J

    2011-07-01

    Acanthochondria cornuta (Copepoda: Chondracanthidae) (N=4841; prevalence: 80·0%; mean±s.d. [range] intensity: 28·8±24·0 [1-110] parasites) infected the branchial chambers of the European flounder, Platichthys flesus (L.), (N=210) according to an established spatial pattern. This was independent of host size. Higher intensities resulted, most frequently, in higher numbers of infection sites, probably due to increased intraspecific competition. Preferential infection of the ocular side was supported by the recorded abundance data and reflected, probably, the fish's bottom-dwelling behaviour. As the parasite develops from one stage into another, it seems to migrate towards different sites: the copepodites and pre-adult females occurred, mainly, in the holobranchs; the adults preferred the internal wall (non-gravid/post-gravid females; adult males) or the pseudobranchs (gravid females). The ventilating water current along with the blood supply are suggested as 2 major factors in determining parasite spatial distribution within the chamber. Parasite crowding in a restricted and narrow space of the posterior region of the internal wall was recorded frequently and resembled that previously reported for the plaice. Differences to other host-parasite systems previously studied should relate with the anatomy of the respiratory apparatus. Bigamous females are reported for the first time.

  12. Seasonality of metazoan ectoparasites in marine European flounder Platichthys flesus (Teleostei: Pleuronectidae).

    PubMed

    Cavaleiro, F I; Santos, M J

    2009-07-01

    Seasonal occurrence of metazoan ectoparasites is described for the first time in marine European flounder, Platichthys flesus (L.). The parasitofauna, in this study monitored during 1 year, was found to be similar to that previously recorded for flounder. Moreover, specimens of Caligus sp. Müller, 1785 and Lepeophtheirus pectoralis (Copepoda: Caligidae), Acanthochondria cornuta (Copepoda: Chondracanthidae), Holobomolochus confusus (Copepoda: Bomolochidae) and Nerocila orbignyi (Isopoda: Cymothoidae), and also, a praniza larva (Isopoda: Gnathiidae), were isolated. From these, L. pectoralis and A. cornuta were the dominant parasites in all samples of flounder, while Caligus sp., H. confusus, N. orbignyi and the gnathiid praniza seemed to infect the flounder only occasionally. As far as the seasonality of infections is concerned, it differed considerably from that described for estuarine environments. Indeed, both prevalence and abundance of L. pectoralis and A. cornuta reached significant peaks in the summer, whereas the literature identifies the autumn as the season of maximum infection on estuarine flounder. Thus, the former period seems more favourable for the occurrence of epizooties of L. pectoralis and A. cornuta in flounder culturing systems running on seawater and operated in the studied or similar environments.

  13. On the electromotor neurons of both electric organs of Pollimyrus isidori (Mormyridae, Teleostei).

    PubMed

    Kirschbaum, F; Denizot, J P; Tsuji, S

    1979-01-01

    The electromotor neurons (EMNs) of the adult electric organ of Pollimyrus isidori and the "giant neurons" (GNs) found in the more rostral part of the spinal cord were investigated both with light and electron microscopical methods. The two kinds of neuron are more or less similar in size, about 30 microns, and are found in the more dorsal part of the spinal cord. The EMNs show somatosomatic gap junctions, as do the GNs. In addition, chemical synapses could be found between nerve fibres and both types of neurons. Histochemical investigations show that the EMNs and the GNs are both AChE positive. On the basis of the arguments presented in the discussion, we believe that the "giant neurons" are the electromotor neurons of the larval electric organ of Pollimyrus isidori.

  14. Chromosomal location of retrotransposable REX 1 in the genomes in five Prochilodus (Teleostei

    PubMed Central

    Voltolin, Tatiana Aparecida; Mendonça, Bruna Bueno; Ferreira, Daniela Cristina; Senhorini, José Augusto; Foresti, Fausto; Porto-Foresti, Fábio

    2013-01-01

    Transposable elements are repetitive DNA sequences comprising a group of segments able to move and carry sequences within the genome. Studies involving comparative genomics have revealed that most vertebrates have different populations of transposable elements with significant differences among species of the same lineage. Few studies have been conducted in fish, the most diverse group of vertebrates, with the objective to locate different types of transposable elements. Therefore, this study proposed to map the retrotransposable element Rex1 applying Fluorescent in situ Hybridization (FISH) in five species of the genus Prochilodus (Prochilodus argenteus, Prochilodus brevis, Prochilodus costatus, Prochilodus lineatus and Prochilodus nigricans). After the application of the Rex1 probe, scattered markings were found throughout the genome of analyzed species, and also the presence of small clusters located in the centromeric and telomeric regions coincident with the heterochromatin distribution pattern. This was the first description of the retrotransposable element Rex1 in Prochilodus genome seeking for a better understanding of the distribution pattern of these retrotransposons in the genome of teleost fish. PMID:24195015

  15. Physiological adaptation along environmental gradients and replicated hybrid zone structure in swordtails (Teleostei: Xiphophorus).

    PubMed

    Culumber, Z W; Shepard, D B; Coleman, S W; Rosenthal, G G; Tobler, M

    2012-09-01

    Local adaptation is often invoked to explain hybrid zone structure, but empirical evidence of this is generally rare. Hybrid zones between two poeciliid fishes, Xiphophorus birchmanni and X. malinche, occur in multiple tributaries with independent replication of upstream-to-downstream gradients in morphology and allele frequencies. Ecological niche modelling revealed that temperature is a central predictive factor in the spatial distribution of pure parental species and their hybrids and explains spatial and temporal variation in the frequency of neutral genetic markers in hybrid populations. Among populations of parentals and hybrids, both thermal tolerance and heat-shock protein expression vary strongly, indicating that spatial and temporal structure is likely driven by adaptation to local thermal environments. Therefore, hybrid zone structure is strongly influenced by interspecific differences in physiological mechanisms for coping with the thermal environment.

  16. Molecular Phylogeny and Biogeography of the Amphidromous Fish Genus Dormitator Gill 1861 (Teleostei: Eleotridae)

    PubMed Central

    Galván-Quesada, Sesángari; Doadrio, Ignacio; Alda, Fernando; Perdices, Anabel; Reina, Ruth Gisela; García Varela, Martín; Hernández, Natividad; Campos Mendoza, Antonio; Bermingham, Eldredge; Domínguez-Domínguez, Omar

    2016-01-01

    Species of the genus Dormitator, also known as sleepers, are representatives of the amphidromous freshwater fish fauna that inhabit the tropical and subtropical coastal environments of the Americas and Western Africa. Because of the distribution of this genus, it could be hypothesized that the evolutionary patterns in this genus, including a pair of geminate species across the Central American Isthmus, could be explained by vicariance following the break-up of Gondwana. However, the evolutionary history of this group has not been evaluated. We constructed a time-scaled molecular phylogeny of Dormitator using mitochondrial (Cytochrome b) and nuclear (Rhodopsin and β-actin) DNA sequence data to infer and date the cladogenetic events that drove the diversification of the genus and to relate them to the biogeographical history of Central America. Two divergent lineages of Dormitator were recovered: one that included all of the Pacific samples and another that included all of the eastern and western Atlantic samples. In contrast to the Pacific lineage, which showed no phylogeographic structure, the Atlantic lineage was geographically structured into four clades: Cameroon, Gulf of Mexico, West Cuba and Caribbean, showing evidence of potential cryptic species. The separation of the Pacific and Atlantic lineages was estimated to have occurred ~1 million years ago (Mya), whereas the four Atlantic clades showed mean times of divergence between 0.2 and 0.4 Mya. The splitting times of Dormitator between ocean basins are similar to those estimated for other geminate species pairs with shoreline estuarine preferences, which may indicate that the common evolutionary histories of the different clades are the result of isolation events associated with the closure of the Central American Isthmus and the subsequent climatic and oceanographic changes. PMID:27074006

  17. Breeding behavior and reproductive life history of the Neosho Madtom, Noturus placidus (Teleostei: Ictaluridae)

    USGS Publications Warehouse

    Bulger, Angela G.; Wilkinson, Christopher D.; Edds, David R.; Wildhaber, Mark L.

    2002-01-01

    The Neosho madtom, Noturus placidus, is a small catfish listed by the U. S. Fish and Wildlife Service as threatened. Little is known of its breeding biology and behavior because high turbidity and flow during its spawning season prevent direct observation in the field, and captive propagation has met with limited success. We held Neosho madtoms in laboratory aquaria in 1996 and 1998 to study sexual dimorphism during breeding season, courtship and nesting behavior, egg and clutch size, and embryological and larval development. We also attempted to induce spawning. Courtship behaviors were recorded on videotape, including “carousel” and “tail curl” displays in which the fish spun in circles, head to tail, then quivered, with the male's tail wrapped around the female's head. Three clutches were observed, all in nest cavities that had been excavated by the fish under a structure; one clutch (1996) consisted of approximately 60 eggs, with a mean chorion diameter of 3.1 mm, and two (1998) consisted of approximately 30 eggs, with mean diameter of 3.7 mm. In all situations, eggs hatched after eight or nine days, and yolk-sacs were fully depleted seven days later. One spawn (1998) occurred after two days of injection with synthetic hormone. Male parental care of eggs and larvae was observed in 1996. Larvae remained in the nest until yolk-sacs were absorbed, after which they dispersed throughout the tank. Dissection of two females that laid clutches in this study revealed previtellogenic eggs in the lumen of ovaries, with a mean chorion diameter of 0.9 mm. Swollen lips of males, distended abdomen of females, and differences in head shape, premaxillary tooth patch coloring, and genital papillae of breeding males and females were documented during spawning periods.

  18. Huangshan population of Chinese Zacco platypus (Teleostei, Cyprinidae) harbors diverse matrilines and high genetic diversity

    PubMed Central

    ZHENG, Xin; ZHOU, Tian-Qi; WAN, Tao; PERDICES, Anabel; YANG, Jin-Quan; TANG, Xin-Sheng; WANG, Zheng-Ping; HUANG, Li-Qun; HUANG, Song; HE, Shun-Ping

    2016-01-01

    Six main mitochondrial DNA (mtDNA) lineages have been described in minnow (Zacco platypus) samples obtained from northern, western and southern China. Perdices et al. (2004) predicted that further sampling of other tributaries might discover more lineages of this species. In this study, we collected 26 Zacco platypus individuals in the Huangshan area of eastern China and determined the cytochrome b (cytb) sequence variations. Combined with reported data in GenBank, we identified ten matrilines (Zacco A-J) in a total of 169 samples, with relatively high molecular divergence found among them. The Huangshan population had the greatest genetic variation among all sampled regions and hosted six of the ten matrilines. Our results highlight the significance of the Huangshan area for the conservation of Zacco platypus. PMID:27029868

  19. Phylogenetic relationships among families of Gadiformes (Teleostei, Paracanthopterygii) based on nuclear and mitochondrial data.

    PubMed

    Roa-Varón, Adela; Ortí, Guillermo

    2009-09-01

    Phylogenetic hypotheses among Gadiformes fishes at the suborder, family, and subfamily levels are controversial. To address this problem, we analyze nuclear and mitochondrial DNA (mtDNA) sequences for the most extensive taxonomic sampling compiled to date, representing all of the recognized families and subfamilies in the order (except the monotypic family Lyconidae). Our study sampled 117 species from 46 genera, comprising around 20% of the species described for the order (more than 60% of all genera in the order) and produced 2740 bp of DNA sequence data for each species. Our analysis was successful in confirming the monophyly of Gadiformes and most of the proposed families for the order, but alternative hypotheses of sister-group relationships among families were poorly resolved. Our results are consistent with dividing Gadiformes into 12 families in three suborders, Muraenolepidoidei, Macrouroidei, and Gadoidei. Muraenolepidoidei contains the single family Muraenolepididae. The suborder Macrouroidei includes at least three families: Macrouridae, Macruronidae and Steindachneriidae. Macrouridae is deeply divided into two well-supported subfamilies: Macrourinae and Bathygadinae, suggesting that Bathygadinae may be ranked at the family level. The suborder Gadoidei includes the families: Merlucciidae, Melanonidae, Euclichthyidae, Gadidae, Ranicipitidae, and Bregmacerotidae. Additionally, Trachyrincinae could be ranked at family level including two subfamilies: Trachyrincinae and Macrouroidinae within Gadoidei. Further taxonomic sampling and sequencing efforts are needed in order to corroborate these relationships.

  20. Gaidropsarus (Gadidae, Teleostei) of the North Atlantic Ocean: a brief phylogenetic review.

    PubMed

    Francisco, S M; Robalo, J I; Stefanni, S; Levy, A; Almada, V C

    2014-08-01

    The phylogenetic relationships among the North Atlantic Gaidropsarus and between the three Gaidropsarinae genera Gaidropsarus, Ciliata and Enchelyopus are reviewed with the hitherto most comprehensive taxonomic sampling of this group. Phylogenetic results (maximum parsimony, maximum likelihood and Bayesian inference) based on nuclear (rhodopsin) and concatenated mitochondrial (12s, 16s and cytb) markers clearly support this subfamily. For the north-eastern Atlantic species of Gaidropsarus, two previously unreported clades were strongly supported, clarifying the relationships within the genus, and revealing fewer distinct taxa in the north Atlantic Gaidropsarus than previously stipulated. The data challenge the specific status of Gaidropsarus mediterraneus and Gaidropsarus guttatus and raise doubts concerning the distinctiveness of other species. A taxonomic revision of the genus is suggested.

  1. The complete mitochondrial genome of the Gray's grenadier anchovy Coilia grayii (Teleostei, Engraulidae).

    PubMed

    Li, Qiang; Wu, Xiaorui; Shu, Hu; Yang, Huaqiang; Yang, Lidong; Yue, Lei

    2016-01-01

    In this paper, the complete mitochondrial DNA (mtDNA) sequence of Coilia grayii was determined. The mitochondrial genome was 16,851 bp in length, including 13 protein-coding genes, 2 ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs) and a non-coding control region as those found in other vertebrates, with the gene identical to that of typical vertebrates. The overall base composition of the heavy strand were 26.09% of A, 31.14% of T, 15.58% of C and 27.19% of G, with a slight AT bias of 57.23%. With the exception of ND6 and eight tRNA genes, all other mitochondrial genes were encoded on the heavy strand.

  2. Parasitisation by Bathycreadium elongatum (Digenea, Opecoelidae) in pyloric caeca of Trachyrincus scabrus (Teleostei, Macrouridae).

    PubMed

    Constenla, M; Carrassón, M; Moyà, C M; Fernàndez-Chacón, A; Padrós, F; Repullés-Albelda, A; Montero, F E

    2011-10-06

    A novel process of transmural passive displacement of a digenean parasite was studied in the digestive tract of the roughsnout grenadier Trachyrincus scabrus, which is found in the northwestern Mediterranean Sea. This mechanism seems to facilitate the elimination of a significant portion of intestinal parasites. The digenean parasite Bathycreadium elongatum was found in the intestine, mainly within pyloric caeca, in 74.4% of T. scabrus, with a mean abundance of 44 individuals per fish. Nodule-like lesions were also found in the mesentery of pyloric caeca of infected T. scabrus. Histological sections of the nodules revealed granulomatous inflammatory responses surrounding degraded digeneans. Partial nucleotide sequences of the 28S rRNA gene obtained from intracaecal B. elongatum and from the core of the nodules of the mesentery of pyloric caeca showed 100% mutual identity with an overlap of 971 bp. The greatest abundance of both intracaecal B. elongatum and nodules occurred in spring. During summer, and especially autumn, the abundance of intracaecal B. elongatum decreased. Prevalence and abundance of nodules increased in autumn. In winter intracaecal parasite abundance and prevalence began to increase, but decreased again in nodules. During spring and summer, parasites pass into the visceral cavity, hypothetically owing to the fragility of the wall of pyloric caeca in their apical zone, and become degraded through a granulomatous inflammatory response. This process seems to have a detrimental effect on the B. elongatum cycle since some of parasites are trapped and degrade in the connective tissue in which they are unable to complete their life cycle.

  3. Repetitive DNA Sequences and Evolution of ZZ/ZW Sex Chromosomes in Characidium (Teleostei: Characiformes)

    PubMed Central

    Pansonato-Alves, José Carlos; da Costa Silva, Guilherme José; Vicari, Marcelo Ricardo; Artoni, Roberto Ferreira; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    Characidium constitutes an interesting model for cytogenetic studies, since a large degree of karyotype variation has been detected in this group, like the presence/absence of sex and supernumerary chromosomes and variable distribution of repetitive sequences in different species/populations. In this study, we performed a comparative cytogenetic analysis in 13 Characidium species collected at different South American river basins in order to investigate the karyotype diversification in this group. Chromosome analyses involved the karyotype characterization, cytogenetic mapping of repetitive DNA sequences and cross-species chromosome painting using a W-specific probe obtained in a previous study from Characidium gomesi. Our results evidenced a conserved diploid chromosome number of 2n = 50, and almost all the species exhibited homeologous ZZ/ZW sex chromosomes in different stages of differentiation, except C. cf. zebra, C. tenue, C. xavante and C. stigmosum. Notably, some ZZ/ZW sex chromosomes showed 5S and/or 18S rDNA clusters, while no U2 snDNA sites could be detected in the sex chromosomes, being restricted to a single chromosome pair in almost all the analyzed species. In addition, the species Characidium sp. aff. C. vidali showed B chromosomes with an inter-individual variation of 1 to 4 supernumerary chromosomes per cell. Notably, these B chromosomes share sequences with the W-specific probe, providing insights about their origin. Results presented here further confirm the extensive karyotype diversity within Characidium in contrast with a conserved diploid chromosome number. Such chromosome differences seem to constitute a significant reproductive barrier, since several sympatric Characidium species had been described during the last few years and no interespecific hybrids were found. PMID:26372604

  4. A new species of redfin (Teleostei, Cyprinidae, Pseudobarbus) from the Verlorenvlei River system, South Africa

    PubMed Central

    Chakona, Albert; Swartz, Ernst R.; Skelton, Paul H.

    2014-01-01

    Abstract Pseudobarbus verloreni, a new species, is described from material collected in the Verlorenvlei River system on the west coast of South Africa. It differs from its congeners (except Pseudobarbus skeltoni, Pseudobarbus burchelli, and Pseudobarbus burgi) by the presence of two pairs of oral barbels. Pseudobarbus verloreni sp. n. can be distinguished from the three currently described double barbeled Pseudobarbus species by the following combination of characters: pigment pattern, generally deeper body relative to standard length, a longer intestine associated with the deeper body form, shorter snout relative to head length, and much shorter anterior barbels relative to head length. The new species is distinguished from Pseudobarbus burgi in the neighbouring Berg River system by its longer head and longer pre-dorsal length. It seems as if Pseudobarbus verloreni sp. n. has been extirpated from the Langvlei River system and face several threats to its survival in the Verlorenvlei River system. PMID:25493062

  5. Evolution of ontogenetic dietary shifts and associated gut features in prickleback fishes (Teleostei: Stichaeidae).

    PubMed

    German, D P; Gawlicka, A K; Horn, M H

    2014-02-01

    We tested the hypothesis that an ontogenetic dietary shift from carnivory to herbivory or omnivory, and concomitant changes in the gut facilitating digestion of algae, are synapomorphies of the tribes Xiphisterini and Esselenichthyini in the family Stichaeidae (pricklebacks). Previous investigations have revealed that two xiphisterine pricklebacks-Xiphister mucosus and Xiphister atropurpureus-become herbivorous or omnivorous, respectively, as their bodies grow larger, and that their guts show related changes in length and function. In this study we found that, with increase in size, the basal member of the Xiphisterini, Phytichthys chirus, showed an increased proportion of algae in its diet, increased activity of α-amylase and decreased activity of aminopeptidase, all of which support the synapomorphy hypothesis. Cebidichthys violaceus, a herbivore in the Esselenichthyini, shows similar ontogenetic changes in diet and digestive tract length and physiology, but these features were not observed in two derived carnivores, Dictyosoma burgeri and Dictyosoma rubrimaculatum, within the clade. These results suggest that herbivory is isolated to C. violaceus within the Esselenichthyini. Allometric relationships of gut length as a function of body size generally follow diet within the Xiphisterini and Esselenichthyini, with herbivores having the longest guts, which become disproportionately longer than body size as the fishes grow, omnivores intermediate gut lengths, and carnivores the shortest. A carnivore from an adjacent clade, Anoplarchus purpurescens, had the shortest gut, which did not change in length relative to body length as the fish grew. Overall, our results clarify the patterns of dietary evolution within the Stichaeidae and lay the foundation for more detailed studies of dietary and digestive specialization in fishes in the family.

  6. The "pseudo-craniovertebral articulation" in the deep-sea fish Stomias boa (Teleostei: Stomiidae).

    PubMed

    Schnell, Nalani K; Bernstein, Peter; Maier, Wolfgang

    2008-05-01

    Many predatory deep-sea fishes show highly specialized modifications of their feeding apparatus, e.g., elongate jaws studded with long daggerlike teeth, often combined with a very distensible stomach, to be capable of swallowing relatively large prey. These striking features can be observed in members of the marine teleost family Stomiidae. The present study gives a detailed morphological description of the mesopelagic predatory fish, Stomias boa, based on a combined approach of clearing and double staining, serial sections and dissection. In this genus, large pads made of dense connective tissue extend from the first enlarged neural arch to the ventral side of the chordal sheath, embracing the prominent exoccipitals and thus constituting a kind of double ball- and socket joint for the head. The notochordal occipito-vertebral gap is enlarged, probably not by loss of vertebral centra as is proposed for other genera of the stomiid family, e.g., in Astronesthes or Photostomias. We conclude that this "pseudo-craniovertebral articulation" serves as a functional substitute for the absent vertebrae and strengthens the flexible, anterior part of the vertebral column during extreme dorsal expansion of the gape during prey capture and swallowing.

  7. Autonomic control of post-air-breathing tachycardia in Clarias gariepinus (Teleostei: Clariidae).

    PubMed

    Teixeira, Mariana Teodoro; Armelin, Vinicius Araújo; Abe, Augusto Shinya; Rantin, Francisco Tadeu; Florindo, Luiz Henrique

    2015-08-01

    The African catfish (Clarias gariepinus) is a teleost with bimodal respiration that utilizes a paired suprabranchial chamber located in the gill cavity as an air-breathing organ. Like all air-breathing fishes studied to date, the African catfish exhibits pronounced changes in heart rate (f H) that are associated with air-breathing events. We acquired f H, gill-breathing frequency (f G) and air-breathing frequency (f AB) in situations that require or do not require air breathing (during normoxia and hypoxia), and we assessed the autonomic control of post-air-breathing tachycardia using an infusion of the β-adrenergic antagonist propranolol and the muscarinic cholinergic antagonist atropine. During normoxia, C. gariepinus presented low f AB (1.85 ± 0.73 AB h(-1)) and a constant f G (43.16 ± 1.74 breaths min(-1)). During non-critical hypoxia (PO2 = 60 mmHg), f AB in the African catfish increased to 5.42 ± 1.19 AB h(-1) and f G decreased to 39.12 ± 1.58 breaths min(-1). During critical hypoxia (PO2 = 20 mmHg), f AB increased to 7.4 ± 1.39 AB h(-1) and f G decreased to 34.97 ± 1.78 breaths min(-1). These results were expected for a facultative air breather. Each air breath (AB) was followed by a brief but significant tachycardia, which in the critical hypoxia trials, reached a maximum of 143 % of the pre-AB f H values of untreated animals. Pharmacological blockade allowed the calculation of cardiac autonomic tones, which showed that post-AB tachycardia is predominantly regulated by the parasympathetic subdivision of the autonomic nervous system.

  8. Mitogenomic Evidence for an Indo-West Pacific Origin of the Clupeoidei (Teleostei: Clupeiformes)

    PubMed Central

    Lavoué, Sébastien; Miya, Masaki; Musikasinthorn, Prachya; Chen, Wei-Jen; Nishida, Mutsumi

    2013-01-01

    The clupeoid fishes are distributed worldwide, with marine, freshwater and euryhaline species living in either tropical or temperate environments. Regional endemism is important at the species and genus levels, and the highest species diversity is found in the tropical marine Indo-West Pacific region. The clupeoid distribution follows two general pattern of species richness, the longitudinal and latitudinal gradients. To test historical hypotheses explaining the formation of these two gradients, we have examined the early biogeography of the Clupeoidei in reconstructing the evolution of their habitat preferences along with their ancestral range distributions on a time-calibrated mitogenomic phylogeny. The phylogenetic results support the distinction of nine main lineages within the Clupeoidei, five of them new. We infer several independent transitions from a marine to freshwater environment and from a tropical to temperate environment that occurred after the initial diversification period of the Clupeoidei. These results combined with our ancestral range reconstruction hypothesis suggest that the probable region of origin and diversification of the Clupeoidei during the Cretaceous period was the tropical marine precursor to the present Indo-West Pacific region. Thus, our study favors the hypotheses of “Region of origin” and “Tropical conservatism” to explain the origins of the longitudinal and latitudinal gradients of clupeoid species richness, respectively. Additional geological and paleontological evidence further define the tropical marine paleo-region of origin as the eastern Tethys Sea region. The Cretaceous fossil record of the Clupeoidei is partially incongruent with the results here as it contains taxa found outside this region. We discuss three possible causes of conflict between our biogeographical hypothesis and the distributions of the Cretaceous clupeoid fossils: regional extinction, incomplete taxonomic sampling and incorrect timescale estimation. PMID:23431379

  9. Reproductive cycles of Mugil cephalus, Liza ramada and Liza aurata (Teleostei: Mugilidae).

    PubMed

    Bartulović, V; Dulčić, J; Matić-Skoko, S; Glamuzina, B

    2011-06-01

    The reproductive cycles of three mullet species from the Eastern Adriatic coast were described using several biological parameters (gonado-somatic index, oocyte diameter and sex ratio) to improve knowledge about their reproduction.

  10. A revision of the species of Saturnius Manter, 1969 (Digenea: Hemiuridae), parasites of mullets (Teleostei: Mugilidae).

    PubMed

    Blasco-Costa, Isabel; Montero, Francisco E; Gibson, David I; Balbuena, Juan Antonio; Raga, Juan Antonio; Shvetsova, Ludmila S; Kostadinova, Aneta

    2008-09-01

    The genus Saturnius Manter, 1969 is defined, its species re-examined and a key to the species presented. S. overstreeti n. sp. is described from Mugil soiuy Basilewsky and M. cephalus L. from the Russian coast of the Sea of Japan and distinguished from the morphologically related S. papernai Overstreet, 1977 and S. maurepasi Overstreet, 1977. S. segmentatus Manter, 1969 is redescribed on the basis of the type- and newly collected material from M. cephalus on the Russian coast of the Sea of Japan. The morphometric variation of S. papernai is studied based on newly collected material from Liza aurata (Risso) in the Ebro Delta and off Santa Pola, Spain. The comparisons reveal lower ranges of most metrical features than previously known. A principal component analysis, carried out after adding the new data to those of Blasco-Costa et al. (2006), confirms the species identification. Other valid species recognised are S. mugilis (Yamaguti, 1970), S. maurepasi, S. belizensis Fischthal, 1977, S. dimitrovi Blasco-Costa et al., 2006 and S. minutus Blasco-Costa et al., 2006. Forms considered species inquirendae are S. valamugilis Rekharani & Madhavi, 1984, Bunocotyle constrictus Domnich & Sarabeev, 1999 [=S. papernai of Domnich & Sarabeev (2000a, b, c, d)], B. mugilis Yamaguti, 1970 of Solonchenko (1976) and S. mugilis of Dmitrieva & Gaevskaya (2001). Host and locality information is given in detail for all species. Lisa ramado (Risso) and Chelon labrosus (Cuvier) are new host records for S. papernai (sensu stricto) and S. dimitrovi. L. aurata is a new host record for S. dimitrovi and S. minutus, and L. saliens (Risso) is a new host record for S. minutus.

  11. Helminth species richness of introduced and native grey mullets (Teleostei: Mugilidae).

    PubMed

    Sarabeev, Volodimir

    2015-08-01

    Quantitative complex analyses of parasite communities of invaders across different native and introduced populations are largely lacking. The present study provides a comparative analysis of species richness of helminth parasites in native and invasive populations of grey mullets. The local species richness differed between regions and host species, but did not differ when compared with invasive and native hosts. The size of parasite assemblages of endohelminths was higher in the Mediterranean and Azov-Black Seas, while monogeneans were the most diverse in the Sea of Japan. The helminth diversity was apparently higher in the introduced population of Liza haematocheilus than that in their native habitat, but this trend could not be confirmed when the size of geographic range and sampling efforts were controlled for. The parasite species richness at the infracommunity level of the invasive host population is significantly lower compared with that of the native host populations that lends support to the enemy release hypothesis. A distribution pattern of the infracommunity richness of acquired parasites by the invasive host can be characterized as aggregated and it is random in native host populations. Heterogeneity in the host susceptibility and vulnerability to acquired helminth species was assumed to be a reason of the aggregation of species numbers in the population of the invasive host.

  12. Migration and reproductive biology of Mugil liza (Teleostei: Mugilidae) in south Brazil.

    PubMed

    Lemos, V M; Varela, A S; Schwingel, P R; Muelbert, J H; Vieira, J P

    2014-09-01

    The mullet Mugil liza occurs along the Atlantic coast of South America from Venezuela to Argentina, but 95% of the commercial catch is collected from south Brazil between São Paulo and Argentina. Mugil liza is a single spawner with oocyte development occurring synchronously in two groups. Spawning happens in marine areas and occurs after migration. The reproductive migration occurs from Argentina (38° S) to the southern Brazilian states (24-26° S) from April to July, with peak spawning in June between northern Santa Catarina and Paraná. The presence of hyaline oocytes was associated with high salinity and sea surface temperatures of 19-21° C, and followed the seasonal northward displacement of these oceanographic conditions. The average size at first maturity (Lm ) for both sexes was 408·3 mm total length, LT . Males (Lm  = 400·1) matured earlier than females (Lm  = 421·9 mm). Fecundity ranged from 818,992 to 2,869,767 oocytes (mean = 1,624,551) in fish that were between 426 and 660 mm LT .

  13. Physoschistura walongensis, a new species of loach (Teleostei: Nemacheilidae) from Arunachal Pradesh, northeastern India.

    PubMed

    Tamang, Lakpa; Sinha, Bikramjit

    2016-10-04

    Physoschistura walongensis, new species, is described from the bank of the Lohit River (upper Brahmaputra River basin) in the eastern most part of the state Arunachal Pradesh at an altitude of 1096 m above sea level. The new species is distinguished from its congeners by the following combination of characters: an incomplete lateral line extending at least to the anal-fin origin and maximally to the tip of the adpressed anal fin, with 71-89 canal pores; a rounded suborbital flap, the posterior margin of which slightly exceeds the anterior orbital margin, occupying less orbital area; body with 11-18 irregular vertical bars on the flank, bars more irregular on the anterior portion of the body than on posterior; 1-4 bars bifurcate ventrally; 1-4 saddles along the ventrolateral side of the body; a moderately thick W-shaped basicaudal bar; a prominent axillary pelvic fin lobe; dark brown mottled markings on the head; and forked caudal fin with 9 upper + 8 lower branched rays.

  14. Ejaculate of sneaker males is pheromonally inconspicuous in the black goby, Gobius niger (Teleostei, Gobiidae).

    PubMed

    Locatello, L; Mazzoldi, C; Rasotto, M B

    2002-11-01

    The black goby, Gobius niger, shows alternative male mating tactics, i.e., parental and sneaker males. Males release a sexual pheromone that attracts females and stimulates aggressive displays in males. This pheromone is produced by the mesorchial gland, a structure well developed in parental males but markedly undeveloped in sneakers. We measured the behavioral response of parental males to the ejaculates of males performing different reproductive tactics. Parental males reacted to the ejaculate of other parental males, with stereotypic aggressive behaviors, but not to the ejaculate of sneakers; consequently sneaker male ejaculate appears to be pheromonally inconspicuous.

  15. Fiber connections and synaptic organization of the preoptic retinopetal nucleus in the filefish (Balistidae, Teleostei).

    PubMed

    Uchiyama, H; Ito, H

    1984-04-23

    Neuron cell bodies of the preoptic retinopetal nucleus (PRN), located in the diencephalon of the filefish , Navodon modestus, project axons to the retina. In the present study, the fiber connections and synaptic organization of the preoptic retinopetal nucleus (PRN) were investigated light- and electron-microscopically. The majority of neural cell bodies are located in the rostral half of this rostro-caudally elongated nucleus. Four types of synaptic terminals are distinguishable. The first (L) consists of large, irregularly shaped terminals that contain electron-dense mitochondria and numerous synaptic vesicles. These profiles make asymmetrical multi-synaptic contacts and gap junctions with somata and dendrites. The L terminals are also presynaptic to a second class of terminals (P), which have pleomorphic synaptic vesicles and form synapses onto dendrites. F terminals which have flat synaptic vesicles were also seen PRN. Very few S terminals were also seen in PRN. This type of terminal contains spherical synaptic vesicles of various sizes and a few pale mitochondria. S terminals form asymmetrical synapses with somata, dendrites and P terminals. Following unilateral tectal ablation, degenerating fibers from the lesion were traced into PRN bilaterally, although ipsilateral projections were far more numerous. L terminals exhibit degenerative changes after large tectal resection, whereas S terminals degenerate after contralateral eye enucleation. Therefore, a tecto-PRN-retinal circuit and a reciprocal connection between the retina and PRN have been documented. The similarity between PRN in the filefish and retinopetal nuclei in other classes of vertebrates, especially the isthmo-optic nucleus in birds, is discussed.

  16. Neoniphon pencei, a new species of holocentrid (Teleostei: Beryciformes) from Rarotonga, Cook Islands

    PubMed Central

    Pyle, Richard L.; Earle, John L.

    2015-01-01

    Abstract Neoniphon pencei, n. sp., is described from thirteen specimens, 132-197 mm standard length (SL) collected from mesophotic coral ecosystems (MCEs) at Rarotonga, Cook Islands by divers using mixed-gas closed-circuit rebreathers. It differs from all other species of the genus in number of lateral line scales, scales above and below lateral line, elements of life color, and in COI and cytochrome b DNA sequences. Of the five other known species of Neoniphon, it is most similar to the Indo-Pacific N. aurolineatus and the western Atlantic N. marianus both morphologically and genetically. PMID:25698898

  17. Fossil calibrations and molecular divergence time estimates in centrarchid fishes (Teleostei: Centrarchidae).

    PubMed

    Near, Thomas J; Bolnick, Daniel I; Wainwright, Peter C

    2005-08-01

    Molecular clock methods allow biologists to estimate divergence times, which in turn play an important role in comparative studies of many evolutionary processes. It is well known that molecular age estimates can be biased by heterogeneity in rates of molecular evolution, but less attention has been paid to the issue of potentially erroneous fossil calibrations. In this study we estimate the timing of diversification in Centrarchidae, an endemic major lineage of the diverse North American freshwater fish fauna, through a new approach to fossil calibration and molecular evolutionary model selection. Given a completely resolved multi-gene molecular phylogeny and a set of multiple fossil-inferred age estimates, we tested for potentially erroneous fossil calibrations using a recently developed fossil cross-validation. We also used fossil information to guide the selection of the optimal molecular evolutionary model with a new fossil jackknife method in a fossil-based model cross-validation. The centrarchid phylogeny resulted from a mixed-model Bayesian strategy that included 14 separate data partitions sampled from three mtDNA and four nuclear genes. Ten of the 31 interspecific nodes in the centrarchid phylogeny were assigned a minimal age estimate from the centrarchid fossil record. Our analyses identified four fossil dates that were inconsistent with the other fossils, and we removed them from the molecular dating analysis. Using fossil-based model cross-validation to determine the optimal smoothing value in penalized likelihood analysis, and six mutually consistent fossil calibrations, the age of the most recent common ancestor of Centrarchidae was 33.59 million years ago (mya). Penalized likelihood analyses of individual data partitions all converged on a very similar age estimate for this node, indicating that rate heterogeneity among data partitions is not confounding our analyses. These results place the origin of the centrarchid radiation at a time of major faunal turnover as the fossil record indicates that the most diverse lineages of the North American freshwater fish fauna originated at the Eocene-Oligocene boundary, approximately 34 mya. This time coincided with major global climate change from warm to cool temperatures and a signature of elevated lineage extinction and origination in the fossil record across the tree of life. Our analyses demonstrate the utility of fossil cross-validation to critically assess individual fossil calibration points, providing the ability to discriminate between consistent and inconsistent fossil age estimates that are used for calibrating molecular phylogenies.

  18. Osteology of Priocharax and remarkable developmental truncation in a miniature Amazonian fish (Teleostei: Characiformes: Characidae).

    PubMed

    Mattox, George M T; Britz, Ralf; Toledo-Piza, Mônica

    2016-01-01

    Establishing phylogenetic relationships of miniature fishes is challenging in taxa with developmental truncation. Within the Characiformes, developmental truncation appears to be relatively rare, with the Neotropical genus Priocharax being an example. Priocharax includes three miniature species among the smallest of the order and has been hypothesized to belong to the Heterocharacinae. The pronounced reduction in its skeleton, however, prevented a clearer evaluation of its relationships. The present detailed osteological study was designed to address this question and revealed that 21 bones are absent and nine other skeletal structures are simplified in Priocharax when compared to other characids. Comparison of the skeleton of adult Priocharax with early developmental stages of other characids demonstrated that most of the absences and simplifications can be interpreted as developmental truncations. The most striking developmental truncations are in the pectoral girdle, in which the endoskeleton remains entirely cartilaginous. Other interesting truncations are in the ethmoid region of the skull, infraorbital series, and Weberian apparatus, in which the claustrum is absent. Our study also revealed some unusual sexual dimorphisms in the pelvic girdle. Two cladistic analyses were performed to assess the relationships of Priocharax within the Heterocharacinae. The first consisted of a traditional analysis in which all absences and reductions of Priocharax were coded in the same way as in the remaining taxa. This resulted in three equally most parsimonious topologies, all of which have Priocharax as the most basal taxon of the Heterocharacinae. The second analysis incorporated ontogenetic information, and most absences and reductions of Priocharax were reinterpreted as apomorphic conditions and thus, coded differently from similar conditions in outgroups. This resulted in a single phylogenetic hypothesis with Priocharax and Gnathocharax as sister groups based on seven synapomorphies. Our approach demonstrates the importance of developmental studies to better understand morphological evolution of miniaturized, truncated taxa, and to generate hypotheses of their relationships.

  19. Cryptic Diversity and Venom Glands in Western Atlantic Clingfishes of the Genus Acyrtus (Teleostei: Gobiesocidae)

    PubMed Central

    Conway, Kevin W.; Baldwin, Carole; White, Macaulay D.

    2014-01-01

    Examination of genetic data (mitochondrial cytochrome c oxidase I) for western Atlantic clingfishes revealed two distinct lineages within a group of individuals originally identified as Acyrtus artius. Subsequent investigation of preserved voucher specimens was conducted to reconcile the genetic data and the existing classification, which is based on morphology. In addition to discovering that one of the genetic lineages is an undescribed species, which we describe as Acyrtus lanthanum, new species, we found that the nominal species Acyrtus artius has a putative venom gland associated with the subopercle that has been overlooked since the species was described nearly 60 years ago. The new species lacks the subopercular gland as does Acyrtus rubiginosus, but one is present in the related Arcos nudus. Venom glands have not been reported previously for the Gobiesocidae, and the venom gland described herein for Acyrtus and Arcos represents the first example in teleost fishes of a venom gland associated with the subopercle. PMID:24825326

  20. [Growth and mortality of the fish Haemulon aurolineatum (Teleostei: Haemulidae) from southwest of Margarita Island, Venezuela].

    PubMed

    Bravo, Edwis; Eslava, Nora; González, Leo

    2009-01-01

    We analyzed the growth and natural mortality of the fish known locally as cuji (H. aurolineatum) in the southwest of Margarita Island, July 2005 to June 2006. A sample of 1,378 males and 1,143 females from artisanal fishing vessels of Boca del Río was analyzed. The common relation for both sexes was expressed by the equation P=0.038*L(2.87). The asymptotic length (L(infinity)) was estimated with Powell's (1979) routine and Wetherall (1986), and the growth coefficient (k) with ELEFAN I - FISAT II (FAO-ICLARM). The modal progression analysis was used after decomposition of lengths frequency according to Bhattacharya, and the estimations of L(infinity), and k optimized according to Gulland and Holt (1959). The growth curve was fitted to von Bertalanffy (1960); it is exponential, with accelerated growth in the first two years and less growth as the fish approaches maximal length. The rate of natural mortality was high (M=1.15 year(-1)), and probably was caused by high depredation.

  1. Sexual ornaments, body morphology, and swimming performance in naturally hybridizing swordtails (teleostei: xiphophorus).

    PubMed

    Johnson, James B; Macedo, Danielle C; Passow, Courtney N; Rosenthal, Gil G

    2014-01-01

    Determining the costs of sexual ornaments is complicated by the fact that ornaments are often integrated with other, non-sexual traits, making it difficult to dissect the effect of ornaments independent of other aspects of the phenotype. Hybridization can produce reduced phenotypic integration, allowing one to evaluate performance across a broad range of multivariate trait values. Here we assess the relationship between morphology and performance in the swordtails Xiphophorus malinche and X. birchmanni, two naturally-hybridizing fish species that differ extensively in non-sexual as well as sexual traits. We took advantage of novel trait variation in hybrids to determine if sexual ornaments incur a cost in terms of locomotor ability. For both fast-start and endurance swimming, hybrids performed at least as well as the two parental species. The sexually-dimorphic sword did not impair swimming performance per se. Rather, the sword negatively affected performance only when paired with a sub-optimal body shape. Studies seeking to quantify the costs of ornaments should consider that covariance with non-sexual traits may create the spurious appearance of costs.

  2. Evolution of the optical releasers for aggressive behavior in cave-dwelling Astyanax fasciatus (Teleostei, Characidae).

    PubMed

    Langecker, T G; Neumann, B; Hausberg, C; Parzefall, J

    1995-07-01

    Epigean and blind cave-dwelling populations of the characid Astyanax fasciatus differ in their agonistic behavior. Epigean specimens are characterized by intense aggressive behavior and territoriality in the laboratory, whereas the blind cave fishes are rarely aggressive and have totally lost the territorial behavior. These behavioral changes are genetically based. In the present study, a comparative analysis of the optical releasers for aggressive behavior has been performed in both epigean and cave-dwelling populations. It was expected that the regression of aggressive behavior should be accompanied by the regression of the genetically fixed optical releasers for aggression in the cave specimens. For the analysis of cave fishes, well-eyed F1-hybrids of cave and epigean specimens (Pachon × Teapao) as well as phylogenetically young cave specimens (Micos) selected for large eyes, have been used. In epigean specimens, aggression is most intensely released by a combination of the signals 'natural shape' and 'locomotion'. The cave populations exhibit a partial regression of the releaser 'natural shape'. 'Locomotion', however, has become a more effective releaser for aggression in cave fishes than it has in their epigean relatives. The results are discussed with respect to their evolutionary significance.

  3. Uncovering the Ancestry of B Chromosomes in Moenkhausia sanctaefilomenae (Teleostei, Characidae).

    PubMed

    Utsunomia, Ricardo; Silva, Duílio Mazzoni Zerbinato de Andrade; Ruiz-Ruano, Francisco J; Araya-Jaime, Cristian; Pansonato-Alves, José Carlos; Scacchetti, Priscilla Cardim; Hashimoto, Diogo Teruo; Oliveira, Claudio; Trifonov, Vladmir A; Porto-Foresti, Fábio; Camacho, Juan Pedro M; Foresti, Fausto

    2016-01-01

    B chromosomes constitute a heterogeneous mixture of genomic parasites that are sometimes derived intraspecifically from the standard genome of the host species, but result from interspecific hybridization in other cases. The mode of origin determines the DNA content, with the B chromosomes showing high similarity with the A genome in the first case, but presenting higher similarity with a different species in the second. The characid fish Moenkhausia sanctaefilomenae harbours highly invasive B chromosomes, which are present in all populations analyzed to date in the Parana and Tietê rivers. To investigate the origin of these B chromosomes, we analyzed two natural populations: one carrying B chromosomes and the other lacking them, using a combination of molecular cytogenetic techniques, nucleotide sequence analysis and high-throughput sequencing (Illumina HiSeq2000). Our results showed that i) B chromosomes have not yet reached the Paranapanema River basin; ii) B chromosomes are mitotically unstable; iii) there are two types of B chromosomes, the most frequent of which is lightly C-banded (similar to euchromatin in A chromosomes) (B1), while the other is darkly C-banded (heterochromatin-like) (B2); iv) the two B types contain the same tandem repeat DNA sequences (18S ribosomal DNA, H3 histone genes, MS3 and MS7 satellite DNA), with a higher content of 18S rDNA in the heterochromatic variant; v) all of these repetitive DNAs are present together only in the paracentromeric region of autosome pair no. 6, suggesting that the B chromosomes are derived from this A chromosome; vi) the two B chromosome variants show MS3 sequences that are highly divergent from each other and from the 0B genome, although the B2-derived sequences exhibit higher similarity with the 0B genome (this suggests an independent origin of the two B variants, with the less frequent, B2 type presumably being younger); and vii) the dN/dS ratio for the H3.2 histone gene is almost 4-6 times higher for B chromosomes than for A chromosome sequences, suggesting that purifying selection is relaxed for the DNA sequences located on the B chromosomes, presumably because they are mostly inactive.

  4. Whole chromosome painting of B chromosomes of the red-eye tetra Moenkhausia sanctaefilomenae (Teleostei, Characidae).

    PubMed

    Scudeler, Patricia Elda Sobrinho; Diniz, Débora; Wasko, Adriane Pinto; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    B chromosomes are dispensable genomic elements found in different groups of animals and plants. In the present study, a whole chromosome probe was generated from a specific heterochromatic B chromosome occurring in cells of the characidae fish Moenkhausia sanctaefilomenae (Steindachner, 1907). The chromosome painting probes were used in fluorescence in situ hybridization (FISH) experiments for the assessment of metaphase chromosomes obtained from individuals from three populations of Moenkhausia sanctaefilomenae. The results revealed that DNA sequences were shared between a specific B chromosome and many chromosomes of the A complement in all populations analyzed, suggesting a possible intra-specific origin of these B chromosomes. However, no hybridization signals were observed in other B chromosomes found in the same individuals, implying a possible independent origin of B chromosome variants in this species. FISH experiments using 18S rDNA probes revealed the presence of non-active ribosomal genes in some B chromosomes and in some chromosomes of the A complement, suggesting that at least two types of B chromosomes had an independent origin. The role of heterochromatic segments and ribosomal sequences in the origin of B chromosomes were discussed.

  5. Uncovering the Ancestry of B Chromosomes in Moenkhausia sanctaefilomenae (Teleostei, Characidae)

    PubMed Central

    Utsunomia, Ricardo; Silva, Duílio Mazzoni Zerbinato de Andrade; Ruiz-Ruano, Francisco J.; Araya-Jaime, Cristian; Pansonato-Alves, José Carlos; Scacchetti, Priscilla Cardim; Hashimoto, Diogo Teruo; Oliveira, Claudio; Trifonov, Vladmir A.; Porto-Foresti, Fábio; Camacho, Juan Pedro M.; Foresti, Fausto

    2016-01-01

    B chromosomes constitute a heterogeneous mixture of genomic parasites that are sometimes derived intraspecifically from the standard genome of the host species, but result from interspecific hybridization in other cases. The mode of origin determines the DNA content, with the B chromosomes showing high similarity with the A genome in the first case, but presenting higher similarity with a different species in the second. The characid fish Moenkhausia sanctaefilomenae harbours highly invasive B chromosomes, which are present in all populations analyzed to date in the Parana and Tietê rivers. To investigate the origin of these B chromosomes, we analyzed two natural populations: one carrying B chromosomes and the other lacking them, using a combination of molecular cytogenetic techniques, nucleotide sequence analysis and high-throughput sequencing (Illumina HiSeq2000). Our results showed that i) B chromosomes have not yet reached the Paranapanema River basin; ii) B chromosomes are mitotically unstable; iii) there are two types of B chromosomes, the most frequent of which is lightly C-banded (similar to euchromatin in A chromosomes) (B1), while the other is darkly C-banded (heterochromatin-like) (B2); iv) the two B types contain the same tandem repeat DNA sequences (18S ribosomal DNA, H3 histone genes, MS3 and MS7 satellite DNA), with a higher content of 18S rDNA in the heterochromatic variant; v) all of these repetitive DNAs are present together only in the paracentromeric region of autosome pair no. 6, suggesting that the B chromosomes are derived from this A chromosome; vi) the two B chromosome variants show MS3 sequences that are highly divergent from each other and from the 0B genome, although the B2-derived sequences exhibit higher similarity with the 0B genome (this suggests an independent origin of the two B variants, with the less frequent, B2 type presumably being younger); and vii) the dN/dS ratio for the H3.2 histone gene is almost 4–6 times higher for B chromosomes than for A chromosome sequences, suggesting that purifying selection is relaxed for the DNA sequences located on the B chromosomes, presumably because they are mostly inactive. PMID:26934481

  6. Descriptions of five new species of Metriaclima (Teleostei: Cichlidae) from Lake Malaŵi, Africa.

    PubMed

    Stauffer, Jay R; Black, Kristin; Konings, Adrianus F

    2013-01-01

    Lake Malaŵi is known for its endemic haplochromine species flock, most notably the rock-dwelling cichlids known as mbuna. One of the larger genera of mbuna is Metriaclima, a group consisting of 31 described species (including the five described herein) and approximately 45 recognized unique populations. Metriaclima is diagnosed by its feeding behavior and several morphological characteristics including the angle of the vomer and the presence of bicuspid teeth in the outer row of both the upper and lower jaws. Metriaclima zebra, the type species for the genus, was described based on a single specimen. While the collection location of this holotype is not known, based on the travel records of its collector, it is likely that the specimen originated from Likoma Island. The holotype was therefore compared to specimens from several localities around this island and was found to be morphologically indistinguishable from some of these. This study includes the morphological analysis of 496 specimens of Metriaclima belonging to 31 collections from Lake Malaŵi. Morphometric differences were analyzed and the relationships among several distinguishable populations of Metriaclima zebra were investigated. Our study further resulted in the description of the following five new species belonging to the M. zebra species complex: M. pambazuko, M. lundoense, M. midomo, M. tarakiki, and M. nigrodorsalis. These species were distinguished and described based on color patterns, morphometric, meristic, and ecological differences. These new species were compared with and distinguished from nearby populations of Metriaclima having similar pigmentation patterns and/or similar ecological niches. An artificial dichotomous key to the described species of Metriaclima is presented.

  7. Shaken not stirred: A molecular contribution to the systematics of genus Mugil (Teleostei, Mugilidae).

    PubMed

    Heras, Sandra; Maltagliati, Ferruccio; Fernández, Maria Victoria; Roldán, María Inés

    2016-07-01

    With this work we addressed some molecular systematic issues within the Mugil cephalus species complex. Particular attention was paid to the debated situations of: (i) Mugil liza, occurring in partial sympatry with Mugil cephalus in the northwestern Atlantic, and (ii) Mugil platanus, considered by some authors a synonymy of the former species and distributed in the southwestern Atlantic. We sequenced 79 individuals of a 465-bp portion of the mitochondrial control region (CR) from 8 western Atlantic and 2 Mediterranean localities. In addition, all CR sequences available from GenBank for the studied taxa were added to our dataset, for a total of 323 individuals. Overall, 229 haplotypes corresponding to 8 divergent monophyletic lineages were detected. Results of phylogenetic analyses were consistent with the occurrence of past speciation events producing the observed lineages. Of these lineages, 7 correspond to cryptic species and one is constituted by M. liza and M. platanus. As a matter of fact, these 2 taxa constitute a single lineage within the M. cephalus species complex. However, individuals of M. liza/M. platanus lineage analyzed by means of the 18 mitochondrial markers available in GenBank exhibited a degree of genetic diversity consistent with highly divergent populations. Of the 8 lineages detected, the Mediterraean one (type locality) corresponds to M. cephalus; the lineage M. liza/M. platanus should be named M. liza, under the priority principle, and the left 6 lineages need formal description.

  8. A further note on the identity of Barbus mussullah Sykes (Teleostei: Cyprinidae)  .

    PubMed

    Knight, J D Marcus; Rai, Ashwin; D'souza, Ronald K P

    2014-06-20

    Knight et al. (2013a) clarified the identity of Barbus mussullah Sykes, the type species of Hypselobarbus Bleeker, showing it to represent a lineage clearly distinct from Tor Gray (type species Tor hamiltonii Gray (= Cyprinus tor Hamilton)). They showed the two species to be distinguished by a suite of characters, with Hypselobarbus lacking the distinctive median fleshy lobe of the lower lip (present in T. tor), having the last simple ray of the dorsal fin weak (vs. strong, 'osseous'), gill rakers long and branched (vs. short and simple, unbranched) on first gill arch, and the proximal end of the fifth ceratobranchial hooked (vs. only slightly curved). Nevertheless, some subsequent authors (e.g., Ambili et al. 2014; Khare et al. 2014) have persisted in referring Barbus mussullah to Tor, in effect synonymyzing Hypselobarbus (in which 12 species are currently recognized) with Tor and thereby causing confusion with regard to the identities of these groups of fishes which, being large and relatively common cyprinids, are of significant economic importance. 

  9. Nematode larvae infecting Priacanthus arenatus Cuvier, 1829 (Pisces: Teleostei) in Brazil.

    PubMed

    Kuraiem, Bianca P; Knoff, Marcelo; Felizardo, Nilza N; Gomes, Delir C; Clemente, Sérgio C São

    2016-05-31

    From July to December, 2013, thirty Priacanthus arenatus specimens commercialized in the cities of Niterói and Rio de Janeiro, State of Rio de Janeiro, were acquired. The fish were necropsied and filleted to investigate the presence of nematode larvae. Twenty fish (66.7%) out of the total were parasitized by nematode larvae. A total of 2024 larvae were collected; among them, 30 third-instar larvae of Anisakis sp. showed prevalence (P) = 20%, mean abundance (MA) = 1, and the mean intensity (MI) = 5, and infection sites (IS) = caecum, stomach, liver, and mesentery; and 1,994 third-instar larvae (1,757 encysted and 237 free) of Hysterothylacium deardorffoverstreetorum with P = 66.7%, MA = 66.5, and MI = 99.7, and IS = spleen, caecum, stomach, liver, mesentery, and abdominal muscle. This is the first study to report H. deardorffoverstreetorum and Anisakis sp. larvae parasitizing P. arenatus.

  10. Cytogenetic analysis of two locariid species (Teleostei, Siluriformes) from Iguatemi River (Parana River drainage) in Brazil

    PubMed Central

    Fernandes, Carlos Alexandre; Alves, Diandra Soares; Guterres, Zaira da Rosa; Martins-Santos, Isabel Cristina

    2015-01-01

    Abstract Fishes of the Loricariidae family, known as “cascudos”, constitute an endemic group in Neotropical freshwaters. In this study, were cytogenetically examined two species of Loricariidae (Pterygoplichthys anisitsi Eigenmann & Kennedy, 1903 and Farlowella amazonum (Günther, 1864) belonging to Hypostominae and Loricariinae subfamilies respectively) from Iguatemi River. Our study provide the first description regarding C-band and fluorochromic analysis in Farlowella amazonum. In Farlowella amazonum, diploid number was 58 chromosomes, with single Ag-NOR and heterochromatic blocks in centromeric regions of some chromosomes and large subtelomeric blocks were evidenced on the long arm of the pair 27, being this region CMA3+/DAPI-. The Pterygoplichthys anisitsi showed diploid number equal 52 chromosomes, with single Ag-NOR and heterochromatic blocks in centromeric and telomeric regions of some chromosomes and conspicuous large telomeric blocks on the long arm of the pair 10, being this region CMA3+/DAPI-. The results show that karyotype formula is nonconservative in Pterygoplichthys anisitsi and Farlowella amazonum. PMID:25893075

  11. Mitogenomic circumscription of a novel percomorph fish clade mainly comprising "Syngnathoidei" (Teleostei).

    PubMed

    Song, Ha Yeun; Mabuchi, Kohji; Satoh, Takashi P; Moore, Jon A; Yamanoue, Yusuke; Miya, Masaki; Nishida, Mutsumi

    2014-06-01

    Percomorpha, comprising about 60% of modern teleost fishes, has been described as the "(unresolved) bush at the top" of the tree, with its intrarelationships still being ambiguous owing to huge diversity (>15,000 species). Recent molecular phylogenetic studies based on extensive taxon and character sampling, however, have revealed a number of unexpected clades of Percomorpha, and one of which is composed of Syngnathoidei (seahorses, pipefishes, and their relatives) plus several groups distributed across three different orders. To circumscribe the clade more definitely, we sampled several candidate taxa with reference to the previous studies and newly determined whole mitochondrial genome (mitogenome) sequences for 16 percomorph species across syngnathoids, dactylopterids, and their putatively closely-related fishes (Mullidae, Callionymoidei, Malacanthidae). Unambiguously aligned sequences (13,872 bp) from those 16 species plus 78 percomorphs and two outgroups (total 96 species) were subjected to partitioned Bayesian and maximum likelihood analyses. The resulting trees revealed a highly supported clade comprising seven families in Syngnathoidei (Gasterosteiformes), Dactylopteridae (Scorpaeniformes), Mullidae in Percoidei and two families in Callionymoidei (Perciformes). We herein proposed to call this clade "Syngnathiformes" following the latest nuclear DNA studies with some revisions on the included families.

  12. Inferring parrotfish (Teleostei: Scaridae) pharyngeal mill function from dental morphology, wear, and microstructure.

    PubMed

    Carr, Andrew; Tibbetts, Ian R; Kemp, Anne; Truss, Rowan; Drennan, John

    2006-10-01

    Morphology, occlusal surface topography, macrowear, and microwear features of parrotfish pharyngeal teeth were investigated to relate microstructural characteristics to the function of the pharyngeal mill using scanning electron microscopy of whole and sectioned pharyngeal jaws and teeth. Pharyngeal tooth migration is anterior in the lower jaw (fifth ceratobranchial) and posterior in the upper jaw (paired third pharyngobranchials), making the interaction of occlusal surfaces and wear-generating forces complex. The extent of wear can be used to define three regions through which teeth migrate: a region containing newly erupted teeth showing little or no wear; a midregion in which the apical enameloid is swiftly worn; and a region containing teeth with only basal enameloid remaining, which shows low to moderate wear. The shape of the occlusal surface alters as the teeth progress along the pharyngeal jaw, generating conditions that appear suited to the reduction of coral particles. It is likely that the interaction between these particles and algal cells during the process of the rendering of the former is responsible for the rupture of the latter, with the consequent liberation of cell contents from which parrotfish obtain their nutrients.

  13. Pempheris gasparinii, a new species of sweeper fish from Trindade Island, southwestern Atlantic (Teleostei, Pempheridae)

    PubMed Central

    Pinheiro, Hudson T.; Bernardi, Giacomo; Rocha, Luiz A.

    2016-01-01

    Abstract Pempheris gasparinii sp. n. is described from five specimens, 59.1–68.0 mm in standard length. It is only known to occur in the shallow reefs of Trindade Island, 1200 km east of the Brazilian coast, in the southwestern Atlantic. Pempheris gasparinii is the third recognized species of Pempheris in the Atlantic Ocean. This new species is morphologically similar to its close relative, Pempheris poeyi, differing by the number of lateral-line scales (51–54 in Pempheris gasparinii vs. 47–49 in Pempheris poeyi), scales below lateral line (10–11 vs. 9), circumpeduncular scales (11–12 vs. 13), head and caudal peduncle lengths (2.7–3.3 vs 3.5–4.0 in head length). Moreover, Pempheris gasparinii shows a 4% genetic divergence from Pempheris poeyi at the cytochrome oxidase I locus (COI), consistent with a lineage split at the beginning of the Pleistocene. This new species represents the 12th endemic fish species from Trindade Island. PMID:27006618

  14. The Infrabranchial Musculature and Its Bearing on the Phylogeny of Percomorph Fishes (Osteichthyes: Teleostei)

    PubMed Central

    Datovo, Aléssio; de Pinna, Mário C. C.; Johnson, G. David

    2014-01-01

    The muscles serving the ventral portion of the gill arches ( = infrabranchial musculature) are poorly known in bony fishes. A comparative analysis of the infrabranchial muscles in the major percomorph lineages reveals a large amount of phylogenetically-relevant information. Characters derived from this anatomical system are identified and discussed in light of current hypotheses of phylogenetic relationships among percomorphs. New evidence supports a sister-group relationship between the Batrachoidiformes and Lophiiformes and between the Callionymoidei and Gobiesocoidei. Investigated data also corroborate the existence of two monophyletic groups, one including the Pristolepididae, Badidae, and Nandidae, and a second clade consisting of all non-amarsipid stromateiforms. New synapomorphies are proposed for the Atherinomorphae, Blenniiformes, Lophiiformes, Scombroidei (including Sphyraenidae), and Gobiiformes. Within the latter order, the Rhyacichthyidae and Odontobutidae are supported as the successive sister families of all remaining gobiiforms. The present analysis further confirms the validity of infrabranchial musculature characters previously proposed to support the grouping of the Mugiliformes with the Atherinomorphae and the monophyly of the Labriformes with the possible inclusion of the Pholidichthyiformes. Interestingly, most hypotheses of relationships supported by the infrabranchial musculature have been advanced by preceding anatomists on the basis of distinct data sources, but were never recovered in recent molecular phylogenies. These conflicts clearly indicate the current unsatisfactory resolution of the higher-level phylogeny of percomorphs. PMID:25310286

  15. Eviota brahmi n. sp. from Papua New Guinea, with a redescription of Eviota nigriventris (Teleostei: Gobiidae).

    PubMed

    Greenfield, David W; Tornabene, Luke

    2014-04-28

    Greenfield & Randall (2011) described the gobiid fishes Eviota dorsogilva from Fiji and E. dorsopurpurea from Papua New Guinea as new species in what they termed the Eviota nigriventris complex. They also extended the range of E. nigriventris, type locality Banda Sea, to Milne Bay, Papua New Guinea. In the present paper, we describe their misidentified E. nigriventris from Papua New Guinea as a new species, E. brahmi, and redescribe E. nigriventris based on new material from near the type locality. The four species of this complex differ mainly in coloration, but are also shown to be distinct using mitochondrial and nuclear DNA.

  16. A new species of seahorse (Teleostei: Syngnathidae) from the South China Sea.

    PubMed

    Zhang, Yan-Hong; Qin, Geng; Wang, Xin; Lin, Qiang

    2016-09-23

    A new species of seahorse, Hippocampus casscsio sp. nov. was collected over shallow seagrass beds in Beibu Bay, China. This species is diagnosed from all other seahorse species by morphological characters, including the lower number of tail rings (35); 15 pectoral-fin rays; 16 dorsal-fin rays; a rounded nuchal plate without a raised coronet; a snout length 30% head length; two cheek spines and a dark brown coloration. In addition, molecular analysis showed all individuals of the new species clustering together suggesting a monophyletic lineage. This combined analysis supports the distinctness of H. casscsio sp. nov. as a new species, which is described herein.

  17. Corrigendum: Redescription of Nemachilichthys rueppelli, a senior synonym of N. shimogensis (Teleostei: Nemacheilidae).

    PubMed

    Keskar, Ashwini; Kumkar, Pradeep; Katwate, Unmesh; Ali, Anvar; Raghavan, Rajeev; Dahanukar, Neelesh

    2016-05-12

    In Keskar et al. (2015) we emended the original name Cobitis rupelli Sykes, 1839, because Sykes (1839) specifically mentions that the species was named after Rüppell. The specific epithet 'rupelli', with a single 'p', is an incorrect original spelling and should be emended into 'ruppelli' as required by Article 32.5 (International Commission on Zoological Nomenclature, 1999). However, citing Art 32.5.2.1, we also suggested that because Sykes (1839) named the species after Rüppell, the umlaut 'ü' should be corrected to 'ue' and that the specific epithet should thus be 'rueppelli'. This is an error. Sykes (1839) did not use 'ü' in the original spelling of the species epithet rupelli: hence changing it to 'ue' is incorrect. Therefore, the correct spelling for the species should be 'Nemachilichthys ruppelli', a change that should be reflected in the title and in the rest of the text of Keskar et al. (2015).

  18. Why is Pseudosphromenus cupanus (Teleostei: Osphronemidae) reported from Bangladesh, Indonesia, Malaysia, Myanmar, and Pakistan?

    PubMed

    Kullander, Sven O; Rahman, Md Mizanur; Norén, Michael; Mollah, Abdur Rob

    2015-07-28

    The native distribution of the small labyrinth fish species Pseudosphromenus cupanus includes southern India and Sri Lanka. According to literature it has a range including also Pakistan, Bangladesh, Myanmar, Malaysia, and Indonesia (Sumatra) but there are no voucher specimens or reliable observations from those areas. The distribution record of P. cupanus was inflated partly by including P. dayi as a synonym. Pseudosphronemus dayi is native to the Western Ghats in India, but the origin of the aquarium importation in 1907 was reported as both Cochin (=Kochi) and Malacca (=Malaysia), the latter locality obviously in error. The basis for the Sumatra record is an obviously mislabeled sample of P. dayi from Pulau Weh close to Sumatra. The basis for reporting the species from Pakistan, Myanmar or Bangladesh could not be located. Misidentified museum specimens from Myanmar and Pakistan identified as P. cupanus were never published on. Pseudosphromenus cupanus has been considered recently to be extinct in Bangladesh, but in fact it never occurred there.

  19. The biology of Solea bleekeri (Teleostei) in Lake St Lucia on the southeast coast of Africa

    NASA Astrophysics Data System (ADS)

    Cyrus, D. P.

    Several aspects of the biology of Solea bleekeri in Lake St Lucia were investigated, these included occurrence, distribution, reproduction and recruitment, food and feeding, size frequency distribution and the role of estuaries in the species' life cycle. Solea bleekeri was found to occur throughout the system in muddy turbid areas and was largely absent from the eastern shores of the lake where clear water sandy substrata occur. The preferred diet of the species was bivalve siphon tips of the species Solon cylindraceus, when these were in abundant supply. However, when numbers of large (length > 20 mm) specimens were not available then S. bleekeri fed on whatever prey was available in or near the substratum. Analysis of stomach contents under the latter conditions showed that food consumption reflected the composition of the benthos. Large numbers of S. bleekeri spend their entire post-larval and juvenile phases as well as the greater part of their adult life within estuaries. Evidence is presented to support the idea that S. bleekeri breeds in certain areas of the lake and that spawning takes place between September and November. The current data suggest that there may be two populations in St Lucia: one migrates from the system to spawn at sea during winter along with the other marine fish species which utilize estuaries as nursery areas, while the other population breeds within the system. Alternatively there may simply be a single population which normally breeds at sea, but which may breed within the system when conditions are suitable. Recruitment of S. bleekeri into the St Lucia estuarine system takes place from the muddy offshore marine banks and possibly from within the system as well. Solea bleekeri appears not to be totally dependent on estuaries for the completion of its life cycle. The advantages of utilizing these systems for their development relate to the shallow, calm, turbid food-rich areas which estuaries offer. The fact that breeding takes place within St Lucia means that adults and juveniles are present in varying numbers throughout the year.

  20. Rivulus berovidesi, a new killifish species (Teleostei: Rivulidae) from western Cuba.

    PubMed

    Silva, Rodet Rodriguez

    2015-04-24

    Rivulus berovidesi, a new killifish species, is described from a small stream in Sierra de Cajalbana, northwestern Cuba. It is readily distinguished from Rivulus cylindraceus Poey by the combination of an exclusive color pattern and meristic characters such as a d-type frontal scalation pattern (versus e-type pattern in Rivulus cylindraceus). The current diagnosis of Rivulus berovidesi based on chromatic, morphological and meristic characters is consistent with a recent molecular analysis of this genus in Cuba.

  1. Herbivory Promotes Dental Disparification and Macroevolutionary Dynamics in Grunters (Teleostei: Terapontidae), a Freshwater Adaptive Radiation.

    PubMed

    Davis, Aaron M; Unmack, Peter J; Vari, Richard P; Betancur-R, Ricardo

    2016-03-01

    Trophic shifts into new adaptive zones have played major (although often conflicting) roles in reshaping the evolutionary trajectories of many lineages. We analyze data on diet, tooth, and oral morphology and relate these traits to phenotypic disparification and lineage diversification rates across the ecologically diverse Terapontidae, a family of Australasian fishes. In contrast to carnivores and most omnivores, which have retained relatively simple, ancestral caniniform tooth shapes, herbivorous terapontids appear to have evolved a variety of novel tooth shapes at significantly faster rates to meet the demands of plant-based diets. The evolution of herbivory prompted major disparification, significantly expanding the terapontid adaptive phenotypic continuum into an entirely novel functional morphospace. There was minimal support for our hypothesis of faster overall rates of integrated tooth shape, spacing, and jaw biomechanical evolution in herbivorous terapontids in their entirety, compared with other trophic strategies. There was, however, considerable support for accelerated disparification within a diverse freshwater clade containing a range of specialized freshwater herbivores. While the evolutionary transition to herbivorous diets has played a central role in terapontid phenotypic diversification by pushing herbivores toward novel fitness peaks, there was little support for herbivory driving significantly higher lineage diversification compared with background rates across the family.

  2. Cytogenetic study of heptapterids (Teleostei, Siluriformes) with particular respect to the Nemuroglanis subclade

    PubMed Central

    Kantek, Daniel Luis Zanella; Moreira Peres, Wellington Adriano; Moreira-Filho, Orlando

    2015-01-01

    Abstract The catfish family Heptapteridae (order Siluriformes) is endemic to the Neotropics and is one of the most common of the fish families in small bodies of water. Although over 200 species have been identified in this family, very few have been characterized cytogenetically. Here, we analyze the chromosome genomes of four species of Heptapteridae: Cetopsorhamdia iheringi (Schubart & Gomes, 1959), 2n = 58, comprising 28 metacentric (m) + 26 submetacentric (sm) + 4 subtelomeric (st) chromosomes; Pimelodella vittata (Lütken, 1874), 2n = 46, comprising 16m + 22sm + 8st; Rhamdia prope quelen (Quoy & Gaimard, 1824), 2n = 58 comprising 26m + 16sm + 14st + 2 acrocentric; and Rhamdiopsis prope microcephala (Lütken, 1874), 2n = 56, comprising 12m + 30sm + 14st. The nucleolus organizer regions (NORs) were located in a single chromosome pair in all species. The two species that belonged to the subclade Nemuroglanis, Cetopsorhamdia iheringi and Rhamdia prope quelen, had a diploid chromosome number of 58 and an interstitial NOR adjacent to a C+ block located on one of the larger chromosome pairs in the complement. Our results from conventional cytogenetic techniques in combination with FISH using 18S and 5S rDNA probes corroborated the taxonomical hypothesis for the formation of the Nemuroglanis subclade. PMID:25893072

  3. Infection of the heart of Pimelodus ornatus (Teleostei, Pimelodidae), by Myxobolus sp. (Myxozoa, Myxobolidae).

    PubMed

    Matos, Edilson; Videira, Marcela; Velasco, Michele; Sanches, Osimar; Clemente, Sergio Carmona de São; Matos, Patricia

    2014-01-01

    The phylum Myxozoa Grassé, 1970, consists of a heterogenous group of around 50 genera that are worldwide disseminated in a wide variety of aquatic media. In the present study, 43 specimens of Pimelodus ornatus were collected from an adjacent area to the Cachoeira do Arari municipality on Marajó Island, in the Brazilian state of Pará, in 2013. Macroscopic analysis showed the presence of whitened plasmodia located in the cardiac muscle and also in the region between the bulbus arteriosus and atrium cordis. Microscopic analysis on the parasitized tissues revealed spores that were typically piriform, with the anterior portion slightly narrower than the posterior end. The spore valves were symmetrical. The present species is placed in the genus Myxobolus Butschli, 1882, because of the presence of a pair of equal polar capsules in each spore. The prevalence of parasitism observed was 13.9% (6/43). This research note reports the first occurrence of Myxobolus as a parasite of the heart in the teleostean fish P. ornatus in the Amazon region and confirms the occurrence of secondary myocarditis in this fish, caused by parasitism by Myxobolus sp. The rarity of this parasitic species of Myxobolus at this tissue site, associated with other spore morphology characteristics in the fish, suggests that it is an undescribed species.

  4. Aspidoras mephisto, new species: The first troglobitic Callichthyidae (Teleostei: Siluriformes) from South America

    PubMed Central

    Bichuette, Maria Elina

    2017-01-01

    Aspidoras mephisto n. sp. is described from the Anésio-Russão cave system, upper Tocantins River basin, Goiás, Brazil. The species can be readily distinguished from its congeners by troglomorphic features and also by presenting the following combination of features: infraorbital 1 generally with well-developed ventral laminar; or moderately developed; poorly-developed serrations on posterior margin of pectoral spine; nuchal plate not externally visible; dorsal fin, even in conspicuously colored specimens, with only dark brown or black chromatophores concentrated on rays, forming spots in some specimens; membranes hyaline; or sparse dark brown or black chromatophores on membranes, not forming any conspicuous pattern; and inner laminar expansion of infraorbital 1 moderately developed. Information about its habitat, ecology, behaviour and conservation status are provided and also a brief description of the juvenile stage. PMID:28248959

  5. Steroid sex hormone dynamics during estradiol-17β induced gonadal differentiation in Paralichthys olivaceus (Teleostei)

    NASA Astrophysics Data System (ADS)

    Sun, Peng; You, Feng; Liu, Mengxia; Wu, Zhihao; Wen, Aiyun; Li, Jun; Xu, Yongli; Zhang, Peijun

    2010-03-01

    Steroid sex hormones, such as estradiol-17β (E2) and testosterone (T), are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gonadal differentiation in the olive flounder Paralichthys olivaceus using histology and radioimmunoassay (RIA). Flounder larvae were divided into five groups (G0-G4), and fed with 0 (control), 0.2, 2, 20 and 100 mg E2/kg feed from 35 to 110 day post hatching (dph). Fish growth in the G1 and G2 groups was not significantly different from that of the control group ( P>0.05), while fish in the G3 and G4 groups were less active and showed growth depression and high mortality. The gonads of fish in the G3 and G4 groups were smaller and surrounded by hyperplastic connective tissue. The frequency of females in the G0-G4 groups was 54.5%, 75.0%, 100%, 100% and 93.3%, respectively. The RIA analyses of E2 and T showed that T levels decreased during gonadal differentiation, and increased slightly at the onset of ovarian differentiation, while E2 levels increased gradually and peaked at the onset of ovarian differentiation in the control group. In the E2-treated groups, T levels decreased before the onset of ovarian differentiation. E2 levels were high on the 48 dph, but declined to a lower level on the 54 dph, and then increased gradually during gonadal differentiation. And a sharp increase of E2 levels were observed in all E2-treated groups at the onset of ovarian differentiation. The data suggest that T and E2 play important roles during gonadal differentiation, and an E2 dose of 2 mg/kg feed could induce sex reversal in P. olivaceus.

  6. Identification and chromosome mapping of repetitive elements in the Astyanax scabripinnis (Teleostei: Characidae) species complex.

    PubMed

    Barbosa, Patrícia; de Oliveira, Luiz Antonio; Pucci, Marcela Baer; Santos, Mateus Henrique; Moreira-Filho, Orlando; Vicari, Marcelo Ricardo; Nogaroto, Viviane; de Almeida, Mara Cristina; Artoni, Roberto Ferreira

    2015-02-01

    Most part of the eukaryotic genome is composed of repeated sequences or multiple copies of DNA, which were considered as "junk DNA", and may be associated to the heterochromatin. In this study, three populations of Astyanax aff. scabripinnis from Brazilian rivers of Guaratinguetá and Pindamonhangaba (São Paulo) and a population from Maringá (Paraná) were analyzed concerning the localization of the nucleolar organizer regions (Ag-NORs), the As51 satellite DNA, the 18S ribosomal DNA (rDNA), and the 5S rDNA. Repeated sequences were also isolated and identified by the Cot - 1 method, which indicated similarity (90%) with the LINE UnaL2 retrotransposon. The fluorescence in situ hybridization (FISH) showed the retrotransposon dispersed and more concentrated markers in centromeric and telomeric chromosomal regions. These sequences were co-localized and interspaced with 18S and 5S rDNA and As51, confirmed by fiber-FISH essay. The B chromosome found in these populations pointed to a conspicuous hybridization with LINE probe, which is also co-located in As51 sequences. The NORs were active at unique sites of a homologous pair in the three populations. There were no evidences that transposable elements and repetitive DNA had influence in the transcriptional regulation of ribosomal genes in our analyses.

  7. Taxonomic revision and stratigraphic provenance of 'Histiophorus rotundu' Woodward 1901 (Teleostei, Perciformes)

    USGS Publications Warehouse

    Monsch, K.A.; Fierstine, H.L.; Weems, R.E.

    2005-01-01

    Until recently, Histiophorus rotundus Woodward 1901, was known from a single, poorly preserved rostrum from the Tertiary phosphate beds near Charleston, South Carolina, an area from which many fossils have been described. The specimen is relatively featureless externally; its internal anatomy is unknown and the documentation of its geological provenance was poor. In an earlier revision the species was transferred to the fossil billfish genus Xiphiorhynchus Van Beneden, 1871. Here we confirm this designation, supported by new morphological studies of the holotype, recently found specimens of Xiphiorhynchus rotundus (Woodward, 1901), and the stratigraphic record of Xiphiorhynchus. The systematic paleontology we present is a contribution to the taxonomic revision of billfishes world-wide. Because the holotype is heavily phosphatized and the type locality was vaguely described, we discuss the geology of the phosphate mining districts of the Charleston region. Based on our studies, we can narrow the possible age of the holotype to late Oligocene or early Miocene. We suggest X. rotundus was extinct by the Burdigalian. 

  8. Petroscirtes pylei, a new saber-toothed blenny from the Fiji Islands (Teleostei: Blenniidae)

    USGS Publications Warehouse

    Smith-Vaniz, W.F.

    2005-01-01

    Petroscirtes pylei is described from three specimens, 20.3-40.9 mm SL, obtained from a deep-water reef off Suva, Viti Levu, Fiji Islands. It is distinguished from all other congeners by its color pattern, including the presence of two dark body stripes, the lower one broadly extending onto the anal fin, and the dorsal fin with a broad, dark basal stripe, superimposed by a conspicuous white spot centered on the 4th spine. Among Petroscirtes, only the new species and P. springeri typically have 12 dorsal-fin spines but they are not closely related. The holotype was collected in 104-110 m, the second deepest depth record for a species of Petroscirtes. Discovery of this new species, and an apparently second new deep-water Petroscrites (uncollected), at a different Fijian reef indicates that our knowledge of the biodiversity of this habitat and of the saber-toothed blennies is very incomplete. Copyright ?? 2005 Magnolia Press.

  9. Demonstration of the extrinsic coagulation pathway in teleostei: Identification of zebrafish coagulation factor VII

    PubMed Central

    Sheehan, John; Templer, Michael; Gregory, Michael; Hanumanthaiah, Ravikumar; Troyer, Dean; Phan, Thao; Thankavel, Bharath; Jagadeeswaran, Pudur

    2001-01-01

    It is not known whether the mammalian mechanism of coagulation initiation is conserved in fish. Identification of factor VII is critical in providing evidence for such a mechanism. A cDNA was cloned from a zebrafish (teleost) library that predicted a protein with sequence similarity to human factor VII. Factor VII was shown to be present in zebrafish blood and liver by Western blot analysis and immunohistochemistry. Immunodepletion of factor VII from zebrafish plasma selectively inhibited thromboplastin-triggered thrombin generation. Heterologous expression of zebrafish factor VII demonstrated a secreted protein (50 kDa) that reconstituted thromboplastin-triggered thrombin generation in immunodepleted zebrafish plasma. These results suggest conservation of the extrinsic coagulation pathway between zebrafish and humans and add credence to the zebrafish as a model for mammalian hemostasis. The structure of zebrafish factor VIIa predicted by homology modeling was consistent with the overall three-dimensional structure of human factor VIIa. However, amino acid disparities were found in the epidermal growth factor-2/serine protease regions that are present in the human tissue factor–factor VIIa contact surface, suggesting a structural basis for the species specificity of this interaction. In addition, zebrafish factor VII demonstrates that the Gla-EGF-EGF-SP domain structure, which is common to coagulation factors VII, IX, X, and protein C, was present before the radiation of the teleosts from the tetrapods. Identification of zebrafish factor VII significantly narrows the evolutionary window for development of the vertebrate coagulation cascade and provides insight into the structural basis for species specificity in the tissue factor–factor VIIa interaction. PMID:11459993

  10. Molecular phylogeny and conservation priorities of the subfamily Acheilognathinae (Teleostei: Cyprinidae).

    PubMed

    Cheng, Peilin; Yu, Dan; Liu, Siqing; Tang, Qiongying; Liu, Huanzhang

    2014-05-01

    It is increasingly accepted that conservation work should consider the evolutionary history of target species. Fishes in the subfamily Acheilognathinae, family Cyprinidae, are, with the exception of three species exclusively distributed in Europe, restricted to Asia and show a distinct spawning behavior in laying their eggs in gill chambers of freshwater mussels. At present, many of the 70 species recognized in this group are facing with serious population decline in China and Japan, and their phylogenetic relationships are not well resolved. In the present study, based on mtDNA cyt b and 12S rRNA gene sequences, we reconstructed a more detailed species-level phylogenetic tree of this group, and assessed species conservation priorities based on their evolutionary distinctiveness. Molecular phylogenetic analyses showed that the Acheilognathinae contains two major clades: Acheilognathus clade and Tanakia-Rhodeus clade. Based on this phylogenetic result, conservation priority analyses were conducted using ED (evolutionary distinctiveness)/HED (heightened evolutionary distinctiveness), and EDGE (evolutionary distinctiveness and global endangeredness)/HEDGE (heightened evolutionary distinctiveness and global endangeredness) methods. The results suggested that T. himantegus, T. lanceolata, A. gracilis, A. imberbis, T. tanago, and A. longipinnis should be ranked as the top-priority species for conservation. According to our results, we also discussed the current conservation efforts of the bitterling fishes and gave suggestions for future work.

  11. Amblyceps accari, a new species of torrent catfish (Teleostei: Amblycipitidae) from the Western Ghats of India.

    PubMed

    Dahanukar, Neelesh; Raghavan, Rajeev; Ali, Anvar; Britz, Ralf

    2016-05-06

    A new species of torrent catfish, Amblyceps accari, is described from the central region of the Western Ghats of India. The new species differs from all its congeners by having 12 branched anal-fin rays (vs. 7-10 in other Amblyceps, rarely 11 in A. tuberculatum). It differs further from all other species of the genus except A. murraystuarti and A. torrentis in having the adipose fin confluent with the dorsal procurrent part of the caudal fin and by the following combination of characters from all its congeners: jaws unequal with lower jaw weakly-projecting, pectoral spine smooth, adipose-fin origin opposite anal-fin origin, dorsal fin to adipose-fin distance more than one fourth of standard length, adipose fin long with its base more than one-fourth of standard length, and deeply forked caudal fin with minute, poorly developed, centrally projecting hooks on the proximal lepidotrichia of central caudal-fin rays. The discovery of the new species represents the first record of this genus from peninsular India.

  12. Genetic Linkage Map of Fishes of the Genus Xiphophorus (Teleostei: Poeciliidae)

    PubMed Central

    Morizot, D. C.; Slaugenhaupt, S. A.; Kallman, K. D.; Chakravarti, A.

    1991-01-01

    Analysis of genotypes of 76 polymorphic loci in more than 2600 backcross hybrid individuals derived from intra- and interspecific genetic crosses of fishes of the genus Xiphophorus (Poeciliidae) resulted in the identification of 17 multipoint linkage groups containing 55 protein-coding loci and one sex chromosome-linked pigment pattern gene. Multipoint linkage analyses identified highly probable gene orders for 10 linkage groups. The total genome length was estimated to be ~18 Morgans. Comparisons of the Xiphophorus linkage map with those of other fishes, amphibians and mammals suggested that fish gene maps are remarkably similar and probably retain many syntenic groups present in the ancestor of all vertebrates. PMID:2004711

  13. Eidinemacheilus, a new generic name for Noemacheilus smithi Greenwood (Teleostei; Nemacheilidae).

    PubMed

    Segherloo, Iraj Hashemzadeh; Ghaedrahmati, Nabiallah; Freyhof, Jörg

    2016-08-05

    Eidinemacheilus, new genus, is described for the troglomorphic Noemacheilus smithi Greenwood. The sole species of the genus is endemic to an aquifer in the Karun River drainage in the Iranian Zagros Mountains. Eidinemacheilus smithi was identified as a species in Paracobitis as both genera share an elevated dorsal adipose crest, a character state being widespread in nemacheilid loaches. Eidinemacheilus is distinguished from all other genera of Nemacheilidae in the Middle East by having 7+7 branched caudal-fin rays, a strongly reduced head canal system, no pigmentation and no eyes. Eidinemacheilus smithi is also distinguished from other genera in the Middle East by a combination of the following character states: pelvic-fin origin behind of a vertical of the dorsal-fin origin, anus slightly in front of the anal-fin origin and no sexual dimorphism in the length of the paired fins. Eidinemacheilus, as a valid genus, is supported by the analysis of mitochondrial DNA data that shows no close affinity to Paracobitis or other nemacheilid genera from Europe, the Middle East and Western India.

  14. Cobitis avicennae, a new species of spined loach from the Tigris River drainage (Teleostei: Cobitidae).

    PubMed

    Mousavi-Sabet, Hamed; Vatandoust, Saber; Esmaeili, Hamid Reza; Geiger, Matthias F; Freyhof, Jörg

    2015-01-30

    Cobitis avicennae, new species, from the Karkheh and Karun sub-drainages in the Tigris catchment is distinguished from other Cobitis species in the Persian Gulf, Kor and the southern Caspian Sea basins by having a single lamina circularis in males, a small comma-shaped black spot on the upper caudal-fin base, 5½ branched anal-fin rays, 5-6 rows of dark spots on the dorsal and caudal fins, scales below the dorsal-fin base with a small focal zone and pigmentation zone Z4 with 12-17 large, partly fused blotches. It is also distinguished from other Cobitis species in the comparison group by six fixed, diagnostic nucleotide substitutions in the mtDNA COI barcode region.

  15. Molecular Phylogeny and Zoogeography of the Capoeta damascina Species Complex (Pisces: Teleostei: Cyprinidae)

    PubMed Central

    Alwan, Nisreen; Esmaeili, Hamid-Reza; Krupp, Friedhelm

    2016-01-01

    Capoeta damascina was earlier considered by many authors as one of the most common freshwater fish species found throughout the Levant, Mesopotamia, Turkey, and Iran. However, owing to a high variation in morphological characters among and within its various populations, 17 nominal species were described, several of which were regarded as valid by subsequent revising authors. Capoeta damascina proved to be a complex of closely related species, which had been poorly studied. The current study aims at defining C. damascina and the C. damascina species complex. It investigates phylogenetic relationships among the various members of the C. damascina complex, based on mitochondrial and nuclear DNA sequences. Phylogenetic relationships were projected against paleogeographical events to interpret the geographic distribution of the taxa under consideration in relation to the area’s geological history. Samples were obtained from throughout the geographic range and were subjected to genetic analyses, using two molecular markers targeting the mitochondrial cytochrome oxidase I (n = 103) and the two adjacent divergence regions (D1-D2) of the nuclear 28S rRNA genes (n = 65). Six closely related species were recognized within the C. damascina complex, constituting two main lineages: A western lineage represented by C. caelestis, C. damascina, and C. umbla and an eastern lineage represented by C. buhsei, C. coadi, and C. saadii. The results indicate that speciation of these taxa is rather a recent event. Dispersal occurred during the Pleistocene, resulting in present-day distribution patterns. A coherent picture of the phylogenetic relationships and evolutionary history of the C. damascina species complex is drawn, explaining the current patterns of distribution as a result of paleogeographic events and ecological adaptations. PMID:27309854

  16. A checklist of macroparasites of Liza haematocheila (Temminck & Schlegel) (Teleostei: Mugilidae)

    PubMed Central

    Kostadinova, Aneta

    2008-01-01

    Background The mugilid fish Liza haematocheila (syn. Mugil soiuy), native to the Western North Pacific, provides opportunities to examine the changes of its parasite fauna after its translocation to the Sea of Azov and subsequent establishment in the Black Sea. However, the information on macroparasites of this host in both ranges of its current distribution comes from isolated studies published in difficult-to-access literature sources. Materials and methods Data from 53 publications, predominantly in Chinese, Russian and Ukrainian, were compiled from an extensive search of the literature and the Host-Parasite Database maintained up to 2005 at the Natural History Museum, London. Results The complete checklist of the metazoan parasites of L. haematocheila throughout its distributional range comprises summarised information for 69 nominal species of helminth and ectoparasitic crustacean parasites, from 45 genera and 27 families (370 host-parasite records in total) and includes the name of the parasite species, the area/locality of the host capture, and the author and date of the published record. The taxonomy is updated and the validity of the records and synonymies are critically evaluated. A comparison of the parasite faunas based on the records in the native and introduced/invasive range of L. haematocheila suggests that a large number of parasite species was 'lost' in the new distributional range whereas an even greater number was 'gained'. Conclusion Although the present checklist provides information that will facilitate future studies, the interesting question of macroparasite faunal diversity in L. haematocheila in its natural and introduced/invasive ranges cannot be dealt with the current data because of unreliability associated with the large number of non-documented and questionable records. This stresses the importance of data quality analysis in using host-parasite database and checklist data. PMID:19117506

  17. Repetitive DNA Sequences and Evolution of ZZ/ZW Sex Chromosomes in Characidium (Teleostei: Characiformes).

    PubMed

    Scacchetti, Priscilla Cardim; Utsunomia, Ricardo; Pansonato-Alves, José Carlos; da Costa Silva, Guilherme José; Vicari, Marcelo Ricardo; Artoni, Roberto Ferreira; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    Characidium constitutes an interesting model for cytogenetic studies, since a large degree of karyotype variation has been detected in this group, like the presence/absence of sex and supernumerary chromosomes and variable distribution of repetitive sequences in different species/populations. In this study, we performed a comparative cytogenetic analysis in 13 Characidium species collected at different South American river basins in order to investigate the karyotype diversification in this group. Chromosome analyses involved the karyotype characterization, cytogenetic mapping of repetitive DNA sequences and cross-species chromosome painting using a W-specific probe obtained in a previous study from Characidium gomesi. Our results evidenced a conserved diploid chromosome number of 2n = 50, and almost all the species exhibited homeologous ZZ/ZW sex chromosomes in different stages of differentiation, except C. cf. zebra, C. tenue, C. xavante and C. stigmosum. Notably, some ZZ/ZW sex chromosomes showed 5S and/or 18S rDNA clusters, while no U2 snDNA sites could be detected in the sex chromosomes, being restricted to a single chromosome pair in almost all the analyzed species. In addition, the species Characidium sp. aff. C. vidali showed B chromosomes with an inter-individual variation of 1 to 4 supernumerary chromosomes per cell. Notably, these B chromosomes share sequences with the W-specific probe, providing insights about their origin. Results presented here further confirm the extensive karyotype diversity within Characidium in contrast with a conserved diploid chromosome number. Such chromosome differences seem to constitute a significant reproductive barrier, since several sympatric Characidium species had been described during the last few years and no interespecific hybrids were found.

  18. A new species of Microcotyle (Monogenea: Microcotylidae) from Scorpaena notata (Teleostei: Scorpaenidae) in the Mediterranean Sea.

    PubMed

    Ayadi, Zouhour El Mouna; Gey, Delphine; Justine, Jean-Lou; Tazerouti, Fadila

    2017-04-01

    We collected specimens of Microcotyle spp. from two species of scorpaeniform fishes off Algeria, namely Scorpaena notata and Helicolenus dactylopterus. The identification of both fishes was confirmed by molecular barcoding of the COI gene. Sequences of COI gene were also obtained for both parasite species. The species from S. notata is described as Microcotyle algeriensis n. sp., on the basis of morphological differences from other species (number of clamps, number of spines in genital atrium, number of testes). Its COI sequence differs from M. sebastis Goto, 1894 (from Sebastes schlegeli from a fish farm in South Korea) by 14.6%. The species from H. dactylopterus is distinct from M. algeriensis on the basis of morphology (number of clamps, number of spines in genital atrium) and COI sequence (4.5% divergence) and is also distinct from M. sebastis in its COI sequence (12.3%). We refrained from describing it as new because M. sebastis, a species originally described from scorpaeniform fishes off Japan, has been recorded in various hosts in the North and South Pacific, Atlantic and Mediterranean (for the latter, in the same host, H. dactylopterus). We believe that correct specific assignment of species of Microcotyle from scorpaeniform fishes needs a detailed morphological and molecular study of representatives from various locations and hosts.

  19. Molecular systematics of the Labeonini inhabiting the karst regions in southwest China (Teleostei, Cypriniformes)

    PubMed Central

    Zheng, Lan-Ping; Chen, Xiao-Yong; Yang, Jun-Xing

    2016-01-01

    Abstract The major phylogenetic pattern of the cyprinid tribe Labeonini has been revealed by previous molecular studies; however, the relationships within a clade that mainly inhabits the karst regions, which we refer to as the “karst group”, in southwest China remain unresolved due to the low taxon sampling. This group includes more than 50% of the genera and species of Labeonini in China. Moreover, more than 90% of the genera of this group are endemic to China. In addition, some new genera and species of Labeonini have been discovered from these karst regions, but their taxonomic validity and phylogenetic position have not been examined. In this contribution, partial sequences of four nuclear (exon 3 of recombination activating protein 1, rhodopsin, early growth response protein 2B gene and interphotoreceptor retinoid binding protein gene) and three mitochondrial genes (cytochrome b, cytochrome oxidase subunit I and 16S ribosomal RNA) from 36 ingroup taxa and 25 outgroup taxa were analyzed to provide a hypothesis of the phylogenetic relationships within the labeonins of the karst regions in China. We propose that the monophyly of Parasinilabeo, Ptychidio, Rectoris and Semilabeo are supported. A new genus, Prolixicheilus, is erected for Pseudogyrinocheilus longisulcus. Cophecheilus bamen is the sister to Prolixicheilus longisulcus. Ptychidio, Pseudocrossocheilus, Semilabeo, Rectoris and Stenorynchoacrum are closely related with high support values. Sinocrossocheilus, Pseudogyrinocheilus, Paraqianlabeo, Hongshuia, Discogobio and Discocheilus form a clade together with high support. Considering molecular results and morphological differences, Parasinilabeo longicorpus and Ptychidio macrops might be the synonyms of Parasinilabeo assimilis and Ptychidio jordani respectively. Comprehensive taxonomic revisions of the two genera Parasinilabeo and Ptychidio may be necessary. PMID:27667927

  20. Whole chromosome painting of B chromosomes of the red-eye tetra Moenkhausia sanctaefilomenae (Teleostei, Characidae)

    PubMed Central

    Scudeler, Patricia Elda Sobrinho; Diniz, Débora; Wasko, Adriane Pinto; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    Abstract B chromosomes are dispensable genomic elements found in different groups of animals and plants. In the present study, a whole chromosome probe was generated from a specific heterochromatic B chromosome occurring in cells of the characidae fish Moenkhausia sanctaefilomenae (Steindachner, 1907). The chromosome painting probes were used in fluorescence in situ hybridization (FISH) experiments for the assessment of metaphase chromosomes obtained from individuals from three populations of Moenkhausia sanctaefilomenae. The results revealed that DNA sequences were shared between a specific B chromosome and many chromosomes of the A complement in all populations analyzed, suggesting a possible intra-specific origin of these B chromosomes. However, no hybridization signals were observed in other B chromosomes found in the same individuals, implying a possible independent origin of B chromosome variants in this species. FISH experiments using 18S rDNA probes revealed the presence of non-active ribosomal genes in some B chromosomes and in some chromosomes of the A complement, suggesting that at least two types of B chromosomes had an independent origin. The role of heterochromatic segments and ribosomal sequences in the origin of B chromosomes were discussed. PMID:26753081

  1. Lake Tanganyika—A 'Melting Pot' of Ancient and Young Cichlid Lineages (Teleostei: Cichlidae)?

    PubMed Central

    Weiss, Juliane D.; Cotterill, Fenton P. D.; Schliewen, Ulrich K.

    2015-01-01

    A long history of research focused on the East Africa cichlid radiations (EAR) revealed discrepancies between mtDNA and nuclear phylogenies, suggesting that interspecific hybridisation may have been significant during the radiation of these fishes. The approximately 250 cichlid species of Lake Tanganyika have their roots in a monophyletic African cichlid assemblage, but controversies remain about the precise phylogenetic origin and placement of different lineages and consequently about L. Tanganyika colonization scenarios. 3312 AFLP loci and the mitochondrial ND2 gene were genotyped for 91 species representing almost all major lacustrine and riverine haplotilapiine east African cichlid lineages with a focus on L. Tanganyika endemics. Explicitly testing for the possibility of ancient hybridisation events, a comprehensive phylogenetic network hypothesis is proposed for the origin and diversification of L. Tanganyika cichlids. Inference of discordant phylogenetic signal strongly suggests that the genomes of two endemic L. Tanganyika tribes, Eretmodini and Tropheini, are composed of an ancient mixture of riverine and lacustrine lineages. For the first time a strong monophyly signal of all non-haplochromine mouthbrooding species endemic to L. Tanganyika (“ancient mouthbrooders”) was detected. Further, in the genomes of early diverging L. Tanganyika endemics Trematocarini, Bathybatini, Hemibatini and Boulengerochromis genetic components of other lineages belonging to the East African Radiation appear to be present. In combination with recent palaeo-geological results showing that tectonic activity in the L. Tanganyika region resulted in highly dynamic and heterogeneous landscape evolution over the Neogene and Pleistocene, the novel phylogenetic data render a single lacustrine basin as the geographical cradle of the endemic L. Tanganyika cichlid lineages unlikely. Instead a scenario of a pre-rift origin of several independent L. Tanganyika precursor lineages which diversified in ancient rivers and precursor lakes and then amalgamated in the extant L. Tanganyika basin is put forward as an alternative: the 'melting pot Tanganyika' hypothesis. PMID:25928886

  2. Etheostoma erythrozonum, a new species of darter (teleostei: Percidae) from the Meramec River drainage, missouri

    USGS Publications Warehouse

    Switzer, J.F.; Wood, R.M.

    2009-01-01

    A new species of darter, Etheostoma erythrozonum, is described from the Meramec River drainage of Missouri, USA. Etheostoma erythrozonum is the first known fish species endemic to the Meramec River drainage. It differs morphologically and genetically from populations of its sister species, Etheostoma tetrazonum, from the Gasconade River, Osage River, and Moreau River drainages. Copyright ?? 2009 ?? Magnolia Press.

  3. Goblet cell types in intestine of tiger barb and black tetra (Cyprinidae, Characidae: Teleostei).

    PubMed

    Leknes, I L

    2014-10-01

    Histochemical properties of goblet cells in intestine of a stomach-less teleost, tiger barb (Puntius tetrazona), and a stomach-containing teleost, black tetra (Gymnocorymbus ternetzi), are described and compared. The intestine goblet cells were mostly wide in both species, but in tiger barb, some of them were markedly thinner. In black tetra, all the intestine goblet cells displayed magenta colour after PAS, whereas in the tiger barb, only the thinner goblet cells displayed such affinity. The latter cell type was coloured strongly magenta when the tissue was treated with alcian blue (pH 2.5) followed by PAS, whereas the wide goblet cells in tiger barb and all goblet cells in black tetra displayed mainly a blue colour after such treatment. Further, the goblet cells in both species were coloured cleanly blue after high iron diamine followed by alcian blue (pH 2.5). The intestine goblet cells in both species displayed a moderate affinity to WGA and concanavalin A lectins and no affinity to DBA. Most of the goblet cells displayed no affinity to PNA, but some of them in the tiger barb displayed a moderate or strong affinity to this lectin. The affinity to WGA was somewhat strengthened after pre-treatment with neuraminidase. These results suggest that tiger barb contains two types or variants of intestinal goblet cells: high numbers of wide cells filled by acidic, non-sulphated mucin and some thinner cells filled by neutral mucin. The intestine goblet cells in black tetra were filled by variable amounts of neutral and acidic mucin, but the total number of such cells is much less than in tiger barb. The present lectin and neuraminidase results suggest that the intestinal mucins in both species contain significant amounts of N-acetylglucosamine, sialic acid and glucose/mannose, but seem to lack N-acetylgalactosamine. However, some of these cells in tiger barb contain moderate to large amounts of galactose. Together, these results suggest significant species-specific features of the intestine goblet cells and mucin types in tiger barb and black tetra. In conclusion, the present results suggest that the diet and feeding habits in stomach-less teleosts compared with stomach-containing teleosts, greatly influence the number of intestine goblet cells and type of mucin in these cells.

  4. Complete mitogenomes of Guinean angelfish (Holacanthus africanus) and Rock beauty (Holacanthus tricolor) (Teleostei: Pomacanthidae).

    PubMed

    Shen, Kang-Ning; Chen, Ching-Hung; Hsiao, Chung-Der

    2016-07-01

    In this study, we used the next-generation sequencing method to deduce two complete mitogenomes of Guinean angelfish (Holacanthus africanus) and Rock beauty (Holacanthus tricolor) for the first time. The assembled mitogenome, consisting of 16,819 bp and 16,625 bp in length, shows 87% similarity with each other. Both mitogenomes follow the typical vertebrate arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes, and a non-coding control region of D-loop. The D-loop contains 1107 bp in H. africanus and 905 bp in H. tricolor and is located between tRNA-Pro and tRNA-Phe. The overall GC content is 46.2% for H. africanus and 45.6% for H. tricolor. The complete mitogenome of Guinean angelfish and Rock beauty deduced in this study provides essential and important DNA molecular data for further phylogenetic and evolutionary analysis for marine angelfish.

  5. Astyanax hastatus Myers, 1928 (Teleostei, Characidae): A new species complex within the genus Astyanax?

    PubMed Central

    2009-01-01

    Four populations of Astyanax hastatus Myers 1928 from the Guapimirim River basin (Rio de Janeiro State) were analyzed and three distinct cytotypes identified. These cytotypes presented 2n = 50 chromosomes, with 4M+8SM+10ST+28A (Cytotype A), 8M+10SM+14ST+18A (Cytotype B), 6M+8SM+4ST+32A (Cytotype C) and scanty heterochromatin, mainly located throughout pericentromeric regions of several chromosomal pairs. No homologies with the As-51 satellite DNA were observed in the three cytotypes, although all of them presented multiple 18S rDNA sites, as detected by both silver nitrate staining and FISH (fluorescent in situ hybridization). The application of the term “species complex” in Astyanax is discussed from a cytotaxonomic viewpoint. PMID:21637509

  6. Synchiropus sycorax, a new species of dragonet from the Philippines (Teleostei: Callionymidae).

    PubMed

    Tea, Yi-Kai; Gill, Anthony C

    2016-10-02

    Synchiropus sycorax n. sp. is described from six specimens (22.6-40.1 mm SL) collected from Jolo Island, Sulu Archipelago, Philippines. It appears to be most closely related to S. tudorjonesi, which ranges from the Maldive Islands through Indonesia and the Philippine Islands to southern Japan. The new species differs from S. tudorjonesi and other congeners in live coloration: head and body bright red, bright yellow ventrally, with prominent white spots on head (one spot or blotch over preopercular spine, two elongate spots behind middle of eye, and one spot behind upper part of eye at about 1 o'clock position) and body (in three rows, an uppermost row beginning below soft dorsal, tracking lateral line to caudal peduncle, a lowermost row extending from above anterior anal fin to caudal peduncle, and a middle row extending obliquely from above pectoral fin to anterior part of lowermost series of spots); males with pelvic fin and pelvic-pectoral membrane bright yellow with broad bluish or greenish grey to black submarginal band across distal third of fin.

  7. Pseudochromis yamasakii, new species of dottyback fish from Japan (Teleostei: Pseudochromidae: Pseudochrominae).

    PubMed

    Gill, Anthony C; Senou, Hiroshi

    2016-10-04

    Gill (2004) recognised fifty-seven species in the Indo-Pacific genus Pseudochromis Rüppell (1835) but noted that the genus is undiagnosed cladistically and effectively serves as a catch-all for species that can't be placed in other pseudochromine genera (sensu Gill 2013). Since publication of Gill's revision, 13 additional species of Pseudochromis have been described, mostly based on recent collections from the highly diverse Coral Triangle area of the West Pacific (Gill & Allen 2004, 2011; Allen et al. 2008; Gill et al. 2009, 2012a,b; Gill & Williams 2011; Gill & Zajonz 2011; Allen & Erdmann 2012). We herein describe an additional new species, which is known on the basis of a single specimen from Kii Peninsula, Honshu, Japan, and from several photographs from the Kii Peninsula and Izu Islands, Japan.

  8. Iranocichla persa, a new cichlid species from southern Iran (Teleostei, Cichlidae).

    PubMed

    Esmaeili, Hamid Reza; Sayyadzadeh, Golnaz; Seehausen, Ole

    2016-01-01

    Iranocichla persasp. n. is described from the Shur, Hasanlangi and Minab River drainages flowing into the Persian Gulf at the Strait of Hormuz in southern Iran. It is distinguished from Iranocichla hormuzensis, from the Mehran River drainage, by nuptial males having a bright orange breast and lower part of the head (vs. black), a poorly developed or invisible (vs. distinctive) "Tilapia-mark" in the dorsal fin and very clear white spots making almost wavy bars or stripes on the caudal fin (vs. without or with very few white spots). Mitochondrial DNA sequence characters suggest that both Iranocichla species are closely related but form two distinct clades, diagnosable by several fixed mutations in ND2, D-loop and partially by COI sequences. Populations from Kol River drainage, which is situated in-between the Mehran and the Shur River drainages, are more similar to Iranocichla hormuzensis in terms of their male nuptial coloration but to Iranocichla persasp. n. in their mitochondrial sequence characters. Their status requires further investigation.

  9. Squalius namak, a new chub from Lake Namak basin in Iran (Teleostei: Cyprinidae).

    PubMed

    Khaefi, Roozbehan; Esmaeili, Hamid Reza; Sayyadzadeh, Golnaz; Geiger, Matthias F; Freyhof, Jörg

    2016-09-19

    Squalius namak, new species, from the endorheic Lake Namak and Kavir basins in Iran, is distinguished from the species of the genus Squalius in the Persian Gulf and the southern Caspian Sea basins by having a wide and thick symphysial knob on the lower jaw, a convex posterior anal-fin margin, a bold, dark-grey or brown, roundish or crescent-shaped blotch at the posterior tip of each flank scale and orange caudal-, anal- and pelvic-fin rays in life. Squalius namak is also characterized by four fixed, diagnostic nucleotide substitutions in the mtDNA COI barcode region.

  10. Changes induced by cadmium in the kidney of Black Sea bream, Mylio macrocephalus (teleostei)

    SciTech Connect

    Ooi, V.E.C.; Law, F.K. )

    1989-11-01

    Cadmium is known to cause injury to most of the internal organs of higher vertebrates. Chronic exposure of cadmium produces histopathological changes in the kidney in man and experimental animals and leads to its preferential accumulation in the liver and kidney. The toxic effects of cadmium on man and experimental animals such as rats, mice and rabbits have been extensively investigated. However, less is known about injurious effects of cadmium on fish, in particular marine fish species. In the present study, the time course of cadmium-induced renal toxicity and histopathological changes of the kidneys of the Black Sea bream, one of the mot common maricultural fish species in Hong Kong, after administration of cadmium chloride are described.

  11. Evolution and phylogenetic application of the MC1R gene in the Cobitoidea (Teleostei: Cypriniformes).

    PubMed

    Tang, Qiong-Ying; Shi, Li-Xia; Liu, Fei; Yu, Dan; Liu, Huan-Zhang

    2016-09-18

    Fish of the superfamily Cobitoidea sensu stricto (namely loaches) exhibit extremely high diversity of color patterns, but so far little is known about their evolutionary mechanism. Melanocortin 1 receptor gene (MC1R) plays an important role during the synthesis of melanin and formation of animal body color patterns. In this study, we amplified and sequenced the partial MC1R gene for 44 loach individuals representing 31 species of four families. Phylogenetic analyses yielded a topology congruent with previous studies using multiple nuclear loci, showing that each of the four families was monophyletic with sister relationships of Botiidae+ (Cobitidae+(Balitoridae+Nemacheilidae)). Gene evolutionary analyses indicated that MC1R in loaches was under purifying selection pressure, with various sites having different dN/dS values. Both Botiidae and Cobitidae had lower dN/dS values than those of background lineages, suggesting their evolution might be strongly affected by purifying selection pressure. For Balitoridae and Nemacheilidae, both had larger dN/dS values than those of background lineages, suggesting they had a faster evolutionary rate under more relaxed selection pressure. Consequently, we inferred that the relatively stable color patterns in Botiidae and Cobitidae might result from the strong purifying selection pressure on the MC1R gene, whereas the complicated and diverse color patterns in Balitoridae and Nemacheilidae might be associated with the relaxed selection pressure. Given the easy experimental procedure for the partial MC1R gene and its excellent performance in reconstructing phylogeny, we suggest this gene could be used as a good molecular marker for the phylogenetic study of fish species.

  12. Molecular cytogenetic study of heterochromatin in Hisonotus leucofrenatus (Teleostei, Loricariidae, Hypoptopomatinae).

    PubMed

    Andreata, Artur Antonio; Ferreira, Daniela Cristina; Foresti, Fausto; Oliveira, Claudio

    2010-02-01

    The fish species Hisonotus leucofrenatus exhibits a large amount of C-band positive segments with different responses after application of the C-banding technique. Type I class named herein appeared to be heavily stained after C-banding in the terminal position of five chromosome pairs and type II class, weakly stained after C-banding in the interstitial or pericentromeric position in nine chromosome pairs and in the supernumerary chromosomes. No variation was observed in type II C-band positive segments, however, type I segments displayed conspicuous polymorphisms, and six cytotypes were detected among the fish analyzed. Chromosomes were also analyzed by CMA(3) and DAPI staining, which showed that type I C-band positive segments comprised both AT-rich and GC-rich DNA, while type II segments were mainly composed of GC-rich sequences. HindIII-digested genomic DNA exhibits fragments of the ladder-like pattern, characteristic of tandemly arrayed repetitive sequences. Two of those fragments corresponding to monomeric and dimeric units of a 78 bp repetitive DNA sequence were cloned and sequenced. The cloned repetitive DNA was used as probe in fluorescent in situ hybridization experiments. The results revealed that these sequences were located in the same position as the type I C-band positive segments. This satellite DNA did not hybridize with DNA from other species of Hisonotus or from other fish of the family Loricariidae, suggesting that this sequence is specific to H. leucofrenatus. The role of these repetitive sequences in the karyotypic evolution of this species is discussed.

  13. Mitogenomic evidence for an Indo-West Pacific origin of the Clupeoidei (Teleostei: Clupeiformes).

    PubMed

    Lavoué, Sébastien; Miya, Masaki; Musikasinthorn, Prachya; Chen, Wei-Jen; Nishida, Mutsumi

    2013-01-01

    The clupeoid fishes are distributed worldwide, with marine, freshwater and euryhaline species living in either tropical or temperate environments. Regional endemism is important at the species and genus levels, and the highest species diversity is found in the tropical marine Indo-West Pacific region. The clupeoid distribution follows two general pattern of species richness, the longitudinal and latitudinal gradients. To test historical hypotheses explaining the formation of these two gradients, we have examined the early biogeography of the Clupeoidei in reconstructing the evolution of their habitat preferences along with their ancestral range distributions on a time-calibrated mitogenomic phylogeny. The phylogenetic results support the distinction of nine main lineages within the Clupeoidei, five of them new. We infer several independent transitions from a marine to freshwater environment and from a tropical to temperate environment that occurred after the initial diversification period of the Clupeoidei. These results combined with our ancestral range reconstruction hypothesis suggest that the probable region of origin and diversification of the Clupeoidei during the Cretaceous period was the tropical marine precursor to the present Indo-West Pacific region. Thus, our study favors the hypotheses of "Region of origin" and "Tropical conservatism" to explain the origins of the longitudinal and latitudinal gradients of clupeoid species richness, respectively. Additional geological and paleontological evidence further define the tropical marine paleo-region of origin as the eastern Tethys Sea region. The Cretaceous fossil record of the Clupeoidei is partially incongruent with the results here as it contains taxa found outside this region. We discuss three possible causes of conflict between our biogeographical hypothesis and the distributions of the Cretaceous clupeoid fossils: regional extinction, incomplete taxonomic sampling and incorrect timescale estimation.

  14. Iranocichla persa, a new cichlid species from southern Iran (Teleostei, Cichlidae)

    PubMed Central

    Esmaeili, Hamid Reza; Sayyadzadeh, Golnaz; Seehausen, Ole

    2016-01-01

    Abstract Iranocichla persa sp. n. is described from the Shur, Hasanlangi and Minab River drainages flowing into the Persian Gulf at the Strait of Hormuz in southern Iran. It is distinguished from Iranocichla hormuzensis, from the Mehran River drainage, by nuptial males having a bright orange breast and lower part of the head (vs. black), a poorly developed or invisible (vs. distinctive) “Tilapia-mark” in the dorsal fin and very clear white spots making almost wavy bars or stripes on the caudal fin (vs. without or with very few white spots). Mitochondrial DNA sequence characters suggest that both Iranocichla species are closely related but form two distinct clades, diagnosable by several fixed mutations in ND2, D-loop and partially by COI sequences. Populations from Kol River drainage, which is situated in-between the Mehran and the Shur River drainages, are more similar to Iranocichla hormuzensis in terms of their male nuptial coloration but to Iranocichla persa sp. n. in their mitochondrial sequence characters. Their status requires further investigation. PMID:27917068

  15. The complete mitochondrial genome of snubnose pompano Trachinotus blochii (Teleostei, Carangidae).

    PubMed

    Zhang, Dianchang; Wang, Long; Guo, Huayang; Ma, Zhenhua; Jiang, Shigui

    2016-01-01

    The complete mitochondrial genome of Trachinotus blochii was determined using the polymerase chain reaction. The complete mitochondrial DNA sequence is 16,558 bp in length. It consists of 13 protein-coding genes, 22 transfer RNA genes, two rRNA genes and two non-coding regions. Overall base composition of its mitochondrial genome is estimated to be 29.21% for A, 15.74% for G, 26.49% for T, 28.56% for C, respectively, with a high A + T content (55.70%). The control region contains three conserved sequence blocks, a termination-associated sequence and a TATA box. The complete mitochondrial genome sequence of T. blochii can provide a basic data for the studies on population structure, molecular systematic, stock evaluation and conservation genetics. It is also helpful to develop the rational management strategies for T. blochii resource.

  16. Chriolepis prolata, a new species of Atlantic goby (Teleostei: Gobiidae) from the North American continental shelf.

    PubMed

    Hastings, Philip A; Findley, Lloyd T

    2015-01-08

    A new species of seven-spined goby of the genus Chriolepis is described from five specimens collected from the continental shelf of the northeastern Gulf of Mexico and Atlantic Ocean off South Carolina in depths of ca 54 to 110 m. The "Platform Goby", Chriolepis prolata, is distinguishable from all other western Atlantic species currently assigned to the genus Chriolepis and the morphologically similar genus Varicus in having pelvic-fin rays one through four branched, the fifth (innermost) pelvic-fin ray unbranched and relatively long (longer than the second ray to longer than all other pelvic-fin rays); most lateral body scales ctenoid, extending anteriorly in a wedge to a level anterior to the first dorsal-fin insertion or nearly to the pectoral-fin axil, with two or more rows of small cycloid scales extending anteriorly to near the pectoral-fin axil, cycloid scales along the bases of the dorsal and anal fins, and no scales on the belly; and the first two anal-fin pterygiophores inserted anterior to the first haemal spine. It closely resembles C. bilix but differs from that species which has a scaled belly, a shorter fifth pelvic-fin ray, prolonged dorsal-fin spines and smaller teeth in the lower jaw. An earlier report of C. bilix from Florida waters apparently refers to C. prolata. 

  17. Molecular systematics of the Labeonini inhabiting the karst regions in southwest China (Teleostei, Cypriniformes).

    PubMed

    Zheng, Lan-Ping; Chen, Xiao-Yong; Yang, Jun-Xing

    2016-01-01

    The major phylogenetic pattern of the cyprinid tribe Labeonini has been revealed by previous molecular studies; however, the relationships within a clade that mainly inhabits the karst regions, which we refer to as the "karst group", in southwest China remain unresolved due to the low taxon sampling. This group includes more than 50% of the genera and species of Labeonini in China. Moreover, more than 90% of the genera of this group are endemic to China. In addition, some new genera and species of Labeonini have been discovered from these karst regions, but their taxonomic validity and phylogenetic position have not been examined. In this contribution, partial sequences of four nuclear (exon 3 of recombination activating protein 1, rhodopsin, early growth response protein 2B gene and interphotoreceptor retinoid binding protein gene) and three mitochondrial genes (cytochrome b, cytochrome oxidase subunit I and 16S ribosomal RNA) from 36 ingroup taxa and 25 outgroup taxa were analyzed to provide a hypothesis of the phylogenetic relationships within the labeonins of the karst regions in China. We propose that the monophyly of Parasinilabeo, Ptychidio, Rectoris and Semilabeo are supported. A new genus, Prolixicheilus, is erected for Pseudogyrinocheilus longisulcus. Cophecheilus bamen is the sister to Prolixicheilus longisulcus. Ptychidio, Pseudocrossocheilus, Semilabeo, Rectoris and Stenorynchoacrum are closely related with high support values. Sinocrossocheilus, Pseudogyrinocheilus, Paraqianlabeo, Hongshuia, Discogobio and Discocheilus form a clade together with high support. Considering molecular results and morphological differences, Parasinilabeo longicorpus and Ptychidio macrops might be the synonyms of Parasinilabeo assimilis and Ptychidio jordani respectively. Comprehensive taxonomic revisions of the two genera Parasinilabeo and Ptychidio may be necessary.

  18. Gonad morphology, gametogenesis, and reproductive modes in fishes of the tribe Starksiini (Teleostei, Blenniiformes).

    PubMed

    Fishelson, Lev; Baldwin, Carole C; Hastings, Philip A

    2013-05-01

    A comparative study of the reproductive organs in 17 of the 30 species of the tribe Starksiini (Labrisomidae, Blenniiformes) and related labrisomids reveals the major traits of gamete form and production and likely reproductive modes. The testes are of the lobular type and have a testicular gland and sperm ducts. Isodiametric sperm (aquasperm) with a globular head or anisodiametric sperm (introsperm) with an elongate head, or both, were observed in the studied species. Both types have either one or two flagella in the sperm tail. Ovaries of the Starksiini are bilobed and exhibit synchronous or asynchronous egg production. Although viviparity or "ovoviviparity" reportedly characterizes the group, our study revealed evidence of both internal and external fertilization and three modes of reproduction. External fertilization or ovuliparity is suggested for the Starksia atlantica and S. lepicoelia species complexes by the presence in males of a short genital papilla that is not reinforced through adhesion with the first anal-fin spine and by the absence of sperm within the ovaries. Internal fertilization and zygoparity is indicated for most species by the presence of an intromittent papilla in males that is adhered to the first anal-fin spine, "nests" of sperm within the ovaries, absence of embryos within the ovarian lamellae and usually thick egg envelopes bearing dense covers of adhesive filaments. Internal fertilization and embryoparity is indicated for starksia fulva and Xenomedea rhodopyga by an intromittent papilla that is adhered to the first anal-fin spine of males, anisodiametric sperm in males, delicate egg envelopes without adhesive filaments and developing embryos within follicular envelopes or within the follicle in females. Although many of these features are seen in the internally fertilizing clinid blennies, starksiins differ in retaining the testicular gland typical of labrisomids and in lacking sperm packaging typical of other internally fertilizing teleosts.

  19. Transcriptome analysis of vertebral bone in the flounder, Paralichthys olivaceus (Teleostei, Pleuronectiformes), using Illumina sequencing.

    PubMed

    Ibaraki, Harumi; Wu, Xiaoming; Uji, Susumu; Yokoi, Hayato; Sakai, Yoshifumi; Suzuki, Tohru

    2015-12-01

    The processes underlying vertebral development in teleosts and tetrapods differ markedly in a variety of ways. At present, the molecular basis of teleost vertebral development and growth is poorly understood. Understanding vertebral development at the molecular level is important for aquaculture to prevent vertebral anomalies that can arise from a variety of factors, including excess vitamin A (all-trans retinol, VA) in the diet. To facilitate studies on teloest vertebral development, we performed transcriptome analysis of four month old flounder, Paralichthys olivaceus, vertebrae using next-generation sequencing. Expression profile obtained demonstrates that some members of the hh, bmp, fgf, wnt gene families, and their receptors, hox, pax, sox, dlx and tbx gene families and ntl, which are known to function in notochord and somite development in embryos, are expressed in the vertebrae. It was also showed that in addition to the retinoic acid receptor (Rar), the vertebrae express alcohol dehydrogenase 1 and retinal dehydrogenase 2 which convert VA to all-trans-retinoic acid (RA). The assembled contigs also included cytochrome p450 family members, which inactivate RA, as well as phosphatidylcholine-retinol O-acetyltransferase, which converts VA to all-trans-retinyl ester, a stock form of VA. These data suggest that in teleost vertebrae, expression of various signals and transcription factors which function in the notochord and somite development is maintained until adult stage, and RA metabolism and signaling are active to regulate transcription of RA-responsible genes, such as hedgehog and hox genes. This is the first transcriptome analysis of teleost fish vertebrae.

  20. Osteology of Paedocypris, a miniature and highly developmentally truncated fish (Teleostei: Ostariophysi: Cyprinidae).

    PubMed

    Britz, R; Conway, K W

    2009-04-01

    Species of the cyprinid genus Paedocypris are among the smallest and most developmentally truncated fishes and vertebrates. Our analysis of their skeletal structure reveals a puzzling combination of extreme developmental truncation and an increased morphological complexity in sexually dimorphic characters. The skeleton of Paedocypris is characterized by reduction and loss and resembles in many aspects that of a larval/early juvenile stage of its close relatives. We found 61 characters that have been affected by developmental truncation. A comparison with the skeletal development of a close relative, the zebrafish Danio rerio, demonstrates that the majority of the absent bones or skeletal structures in Paedocypris are those that appear late in the ossification trajectory of the zebrafish. Thus, their absence in Paedocypris seems to be due to the simple developmental truncation of terminal stages in the ossification sequence. Our study of the sexually dimorphic structures in Paedocypris demonstrates that predominantly the male exhibits the more complex state. In relation to the female, male Paedocypris uniquely possess a cleithrum with a pointed posterior process that covers the scapula laterally, and a more medially situated posterior flange that contacts the dorsal area of the coracoid; a massive and heavily ossified uppermost pectoral radial tightly bound to the scapula; thickened and enlarged three uppermost pectoral-fin rays; a large triangular, dorsolaterally directed process on the outer arm of the massive os suspensorium; and a enlarged and shovel-like anterodorsally directed basipterygium; and a hypertrophied first pelvic-fin ray with additional anterior flanges that support keratinized pads of skin. Female Paedocypris show only one structure that is better developed than in males: the first proximal-middle radial and the anteriormost fin ray of the dorsal fin are more massive and more heavily ossified. Although the function and biological role of these dimorphisms is still unknown, we hypothesize that they are related to a special reproductive behavior. Paedocypris is a prime example for the recent claim that miniaturization among cyprinids is associated with evolutionary novelty only in developmentally truncated miniatures and not in proportioned dwarfs. Paedocypris offers a strong challenge to Schindleria as the most extreme example of developmental truncation known among fishes. We highlight the difficulties that developmentally truncated taxa frequently pose to the resolution of their phylogenetic position and propose an approach to overcome this problem. Our phylogenetic comparison to determine the systematic position of Paedocypris among cyprinids reveals that it shares not only a number of unique absences, but also highly unusual progressive characters with Sundadanio and Danionella, two other Asian miniature cyprinids. We hypothesize that the three genera form a monophyletic group. We further found that Paedocypris and Danionella share a number of uniquely derived characters pointing to a sister group relationship of the two.

  1. Genetic differentiation among natural populations of the Nile tilapia Oreochromis niloticus (Teleostei, cichlidae).

    PubMed

    Agnèse, J F; Adépo-Gourène, B; Abban, E K; Fermon, Y

    1997-07-01

    We analysed the genetic differentiation among 17 natural populations of the Nile tilapia Oreochromis niloticus (Linnaeus, 1758) using allozymes and restriction fragment length polymorphism (RFLP) of mitochondrial DNA (mtDNA). The populations studied, from the River Senegal to Lake Tana and from Lake Manzalla to Lake Baringo, represent all subspecies which have been previously described. Sixteen variable nuclear loci showed that these populations can be clustered in three groups: (1) West African populations (Senegal, Niger, Volta and Chad drainages), (2) Ethiopian Rift Valley populations (Lakes Awasa, Ziway, Koka and the Awash River) and (3) Nile drainage (Manzalla, Cairo, Lake Edward) and Kenyan Rift Valley populations (Lakes Turkana, Baringo and River Suguta). Nine different mtDNA haplotypes were found in the RFLP analysis of a 1 kb portion of the D-loop region. The network obtained showed that there are three geographically distinct groups; all West African populations and O. aureus are clustered, the two Ethiopian Rift Valley populations are distinct and between these two groups are the Kenyan and Ugandan Rift Valley populations. Nile populations show affinities both with West African populations and with specimens from Lakes Tana and Turkana. Taxonomic and biogeographical implications of these results are discussed.

  2. Phylogeny and polyploidy: resolving the classification of cyprinine fishes (Teleostei: Cypriniformes).

    PubMed

    Yang, Lei; Sado, Tetsuya; Vincent Hirt, M; Pasco-Viel, Emmanuel; Arunachalam, M; Li, Junbing; Wang, Xuzhen; Freyhof, Jörg; Saitoh, Kenji; Simons, Andrew M; Miya, Masaki; He, Shunping; Mayden, Richard L

    2015-04-01

    Cyprininae is the largest subfamily (>1300 species) of the family Cyprinidae and contains more polyploid species (∼400) than any other group of fishes. We examined the phylogenetic relationships of the Cyprininae based on extensive taxon, geographical, and genomic sampling of the taxa, using both mitochondrial and nuclear genes to address the phylogenetic challenges posed by polyploidy. Four datasets were analyzed in this study: two mitochondrial gene datasets (465 and 791 taxa, 5604bp), a mitogenome dataset (85 taxa, 14,771bp), and a cloned nuclear RAG1 dataset (97 taxa, 1497bp). Based on resulting trees, the subfamily Cyprininae was subdivided into 11 tribes: Probarbini (new; Probarbus+Catlocarpio), Labeonini Bleeker, 1859 (Labeo & allies), Torini Karaman, 1971 (Tor, Labeobarbus & allies), Smiliogastrini Bleeker, 1863 (Puntius, Enteromius & allies), Poropuntiini (Poropuntius & allies), Cyprinini Rafinesque, 1815 (Cyprinus & allies), Acrossocheilini (new; Acrossocheilus & allies), Spinibarbini (new; Spinibarbus), Schizothoracini McClelland, 1842 (Schizothorax & allies), Schizopygopsini Mirza, 1991 (Schizopygopsis & allies), and Barbini Bleeker, 1859 (Barbus & allies). Phylogenetic relationships within each tribe were discussed. Two or three distinct RAG1 lineages were identified for each of the following tribes Torini, Cyprinini, Spinibarbini, and Barbini, indicating their hybrid origin. The hexaploid African Labeobarbus & allies and Western Asian Capoeta are likely derived from two independent hybridization events between their respective maternal tetraploid ancestors and Cyprinion.

  3. Molecular Phylogeny and Biogeography of the Amphidromous Fish Genus Dormitator Gill 1861 (Teleostei: Eleotridae).

    PubMed

    Galván-Quesada, Sesángari; Doadrio, Ignacio; Alda, Fernando; Perdices, Anabel; Reina, Ruth Gisela; García Varela, Martín; Hernández, Natividad; Campos Mendoza, Antonio; Bermingham, Eldredge; Domínguez-Domínguez, Omar

    2016-01-01

    Species of the genus Dormitator, also known as sleepers, are representatives of the amphidromous freshwater fish fauna that inhabit the tropical and subtropical coastal environments of the Americas and Western Africa. Because of the distribution of this genus, it could be hypothesized that the evolutionary patterns in this genus, including a pair of geminate species across the Central American Isthmus, could be explained by vicariance following the break-up of Gondwana. However, the evolutionary history of this group has not been evaluated. We constructed a time-scaled molecular phylogeny of Dormitator using mitochondrial (Cytochrome b) and nuclear (Rhodopsin and β-actin) DNA sequence data to infer and date the cladogenetic events that drove the diversification of the genus and to relate them to the biogeographical history of Central America. Two divergent lineages of Dormitator were recovered: one that included all of the Pacific samples and another that included all of the eastern and western Atlantic samples. In contrast to the Pacific lineage, which showed no phylogeographic structure, the Atlantic lineage was geographically structured into four clades: Cameroon, Gulf of Mexico, West Cuba and Caribbean, showing evidence of potential cryptic species. The separation of the Pacific and Atlantic lineages was estimated to have occurred ~1 million years ago (Mya), whereas the four Atlantic clades showed mean times of divergence between 0.2 and 0.4 Mya. The splitting times of Dormitator between ocean basins are similar to those estimated for other geminate species pairs with shoreline estuarine preferences, which may indicate that the common evolutionary histories of the different clades are the result of isolation events associated with the closure of the Central American Isthmus and the subsequent climatic and oceanographic changes.

  4. Molecular phylogeny of the Neotropical fish genus Tetragonopterus (Teleostei: Characiformes: Characidae).

    PubMed

    Melo, Bruno F; Benine, Ricardo C; Silva, Gabriel S C; Avelino, Gleisy S; Oliveira, Claudio

    2016-01-01

    Tetragonopterinae encompasses characid species of the genus Tetragonopterus, which are widely distributed throughout east of the Andes in South America. While taxonomy has recently clarified the species diversity and molecular evidence strongly supports the monophyly of Tetragonopterus, no interspecific relationship studies are currently available. Here we used a large molecular dataset composed of two mitochondrial and three nuclear loci containing an extensive taxon sampling within the family Characidae and included eleven species of Tetragonopterus to generate the first time-calibrated phylogeny for Tetragonopterinae. Our results support monophyly of the subfamily represented solely by Tetragonopterus and corroborate previous molecular hypothesis of close relationship with Exodon plus Roeboexodon and the subfamily Characinae. Internally, we found Moenkhausia georgiae as sister species to all remaining species followed by T. rarus, being both species endemic to the Guiana Shield drainages. Species-level relationships are first hypothesized and putative morphological apomorphies are discussed as support to monophyletic clades. Our time-calibrated phylogeny suggested an origin of the genus during the Late Oligocene-Early Miocene. We hypothesized that the Andean geological activity followed by transformations in the Amazonian hydrographic scenario during the Miocene may have promoted most of the lineage diversification within the Tetragonopterus.

  5. The infrabranchial musculature and its bearing on the phylogeny of percomorph fishes (Osteichthyes: Teleostei).

    PubMed

    Datovo, Aléssio; de Pinna, Mário C C; Johnson, G David

    2014-01-01

    The muscles serving the ventral portion of the gill arches ( = infrabranchial musculature) are poorly known in bony fishes. A comparative analysis of the infrabranchial muscles in the major percomorph lineages reveals a large amount of phylogenetically-relevant information. Characters derived from this anatomical system are identified and discussed in light of current hypotheses of phylogenetic relationships among percomorphs. New evidence supports a sister-group relationship between the Batrachoidiformes and Lophiiformes and between the Callionymoidei and Gobiesocoidei. Investigated data also corroborate the existence of two monophyletic groups, one including the Pristolepididae, Badidae, and Nandidae, and a second clade consisting of all non-amarsipid stromateiforms. New synapomorphies are proposed for the Atherinomorphae, Blenniiformes, Lophiiformes, Scombroidei (including Sphyraenidae), and Gobiiformes. Within the latter order, the Rhyacichthyidae and Odontobutidae are supported as the successive sister families of all remaining gobiiforms. The present analysis further confirms the validity of infrabranchial musculature characters previously proposed to support the grouping of the Mugiliformes with the Atherinomorphae and the monophyly of the Labriformes with the possible inclusion of the Pholidichthyiformes. Interestingly, most hypotheses of relationships supported by the infrabranchial musculature have been advanced by preceding anatomists on the basis of distinct data sources, but were never recovered in recent molecular phylogenies. These conflicts clearly indicate the current unsatisfactory resolution of the higher-level phylogeny of percomorphs.

  6. Effects of aluminum on the energetic substrates in neotropical freshwater Astyanax bimaculatus (Teleostei: Characidae) females.

    PubMed

    Vieira, Vanessa A R O; Correia, Tiago G; Moreira, Renata G

    2013-01-01

    We investigated the effects of acidic pH and acute aluminum (Al) exposure on the metabolic substrates of Astyanax bimaculatus, and on the ability of these animals to recover in clean water. After an acclimation period, sexually mature A. bimaculatus females were sorted into six glass aquaria with three experimental groups: control in neutral pH (7.0), acidic pH (5.5), and Al (0.5 mg·L(-1)) in acidic pH (5.5). After a 96 h treatment, 10 animals from each experimental group were sampled and the rest were returned to clean water in neutral pH without Al for a recovery period of 96 h. The acidic pH, either alone or combined with Al, decreased T4 levels, whereas Al exposure increased T3 levels. Recovery of T3 levels occurred after 96 h. Al exposure decreased ovary and plasma proteins, muscle glycogen contents, and hepatic lipids due to lipoperoxidation. In the recovery phase, lipids decreased in most tissues, probably to re-establish ovary protein and hepatic glycogen. A. bimaculatus prioritized the use of energetic resources during acclimatization to Al instead of prioritizing reproduction, thereby avoiding the ovulation of impaired eggs.

  7. Three new species of blood flukes (Digenea: Aporocotylidae) infecting pufferfishes (Teleostei: Tetraodontidae) from off Bali, Indonesia.

    PubMed

    Yong, R Q-Y; Cutmore, S C; Bray, R A; Miller, T L; Semarariana, I W Y; Palm, H W; Cribb, T H

    2016-10-01

    We describe three new species of blood flukes (Aporocotylidae) and propose their classification within the genus Psettarium Goto & Ozaki, 1929. All three species were collected from the circulatory systems of pufferfishes caught off Bali, central Indonesia. Psettarium pulchellum n. sp. was found in the gills of both the narrow-lined puffer (Arothron manilensis de Procé) and the spiny blaasop (Tylerius spinosissimus Regan), while P. ogawai n. sp. and P. jimbaranense n. sp. were found in the gills of the reticulated puffer (Arothron reticularis Bloch & Schneider). The morphological characteristics of these taxa necessitated emendation of the diagnosis for the genus Psettarium, to accommodate the presence of an oral sucker, multiple or entirely post-caecal testes and a degenerate posterior testis. Features such as proportion of body length occupied by the oesophagus, and posterior caeca being ≥7× the length of anterior caeca, are no longer regarded as useful genus-level characters. Additionally, Sasala nolani is reassigned to this genus as Psettarium nolani n. comb. In phylogenetic analyses of the 28S and ITS2 rDNA regions, all three new taxa form a well-supported clade, together with Psettarium sinense and Psettarium nolani n. comb., the two other species of tetraodontid-infecting aporocotylids for which comparative rDNA data were available. The short branch lengths within this clade, despite dramatic morphological differences between the five species, suggest that rapid morphological diversification has occurred among the tetraodontid-infecting aporocotylids. The genus Psettarium has long been considered problematic. Further commentary is given on the history of this genus and how the issues presented might be resolved.

  8. Discovering Hidden Diversity of Characins (Teleostei: Characiformes) in Ecuador’s Yasuní National Park

    PubMed Central

    Escobar-Camacho, Daniel; Barriga, Ramiro; Ron, Santiago R.

    2015-01-01

    Background Management and conservation of biodiversity requires adequate species inventories. The Yasuní National Park is one of the most diverse regions on Earth and recent studies of terrestrial vertebrates, based on genetic evidence, have shown high levels of cryptic and undescribed diversity. Few genetic studies have been carried out in freshwater fishes from western Amazonia. Thus, in contrast with terrestrial vertebrates, their content of cryptic diversity remains unknown. In this study, we carried out genetic and morphological analyses on characin fishes at Yasuní National Park, in eastern Ecuador. Our goal was to identify cryptic diversity among one of the most speciose fish families in the Amazon region. This is the first time that genetic evidence has been used to assess the species content of the Napo Basin, one of the richest regions in vertebrate diversity. Results Phylogenetic analyses of partial mitochondrial 16S ribosomal RNA gene (∼600 pb) DNA sequences from 232 specimens of the family Characidae and its closest groups revealed eight candidate new species among 33 species sampled, representing a 24% increase in species number. Analyses of external morphology allowed us to confirm the species status of six of the candidate species. Conclusions Our results show high levels of cryptic diversity in Amazonian characins. If this group is representative of other Amazonian fish, our results would imply that the species richness of the Amazonian ichthyofauna is highly underestimated. Molecular methods are a necessary tool to obtain more realistic inventories of Neotropical freshwater fishes. PMID:26275041

  9. Metazoan ectoparasites of Atlantic mackerel, Scomber scombrus (Teleostei: Scombridae): macro- and microhabitat distribution.

    PubMed

    Castro, Ricardo; Santos, Maria João

    2013-10-01

    Parasites are affected by the environment where their hosts live, having a specific distribution among their hosts and occupying a well-defined microhabitat. The present work aims to describe the metazoan ectoparasite fauna of Scomber scombrus, namely its distribution at the macro- and microhabitat levels. For that, fish from two different Portuguese regions, Matosinhos (n = 40) and Figueira da Foz (n = 39), were examined for macroectoparasites. S. scombrus of Matosinhos presented four different parasite species, whilst fish from Figueira da Foz presented five species. All parasites belonged to Monogenea, Copepoda, or Isopoda. The main differences between infection levels of fish from the two localities were found in Grubea cochlear (higher infection levels in Matosinhos) and Caligus pelamydis (where the highest values were found in Figueira da Foz). Regarding the microhabitat of the reported ectoparasites, it could be seen that every species has a very specific distribution within the host: G. cochlear and Kuhnia scombri have a preference for the inner medial areas of gills, Kuhnia sprostonae for the pseudobranchs, and C. pelamydis for the internal wall of opercula. The numerical and functional responses to interspecific competition were absent. These results support the idea that the parasite driving forces of community structure are the reinforcement of reproductive barriers and the enhancement of chances to mate.

  10. Microsatellite variation and genetic structuring in Mugil liza (Teleostei: Mugilidae) populations from Argentina and Brazil

    NASA Astrophysics Data System (ADS)

    Mai, Ana C. G.; Miño, Carolina I.; Marins, Luis F. F.; Monteiro-Neto, Cassiano; Miranda, Laura; Schwingel, Paulo R.; Lemos, Valéria M.; Gonzalez-Castro, Mariano; Castello, Jorge P.; Vieira, João P.

    2014-08-01

    The mullet Mugil liza is distributed along the Atlantic coast of South America, from Argentina to Venezuela, and it is heavily exploited in Brazil. We assessed patterns of distribution of neutral nuclear genetic variation in 250 samples from the Brazilian states of Rio de Janeiro, São Paulo, Santa Catarina and Rio Grande do Sul (latitudinal range of 23-31°S) and from Buenos Aires Province in Argentina (36°S). Nine microsatellite loci revealed 131 total alleles, 3-23 alleles per locus, He: 0.69 and Ho: 0.67. Significant genetic differentiation was observed between Rio de Janeiro samples (23°S) and those from all other locations, as indicated by FST, hierarchical analyses of genetic structure, Bayesian cluster analyses and assignment tests. The presence of two different demographic clusters better explains the allelic diversity observed in mullets from the southernmost portion of the Atlantic coast of Brazil and from Argentina. This may be taken into account when designing fisheries management plans involving Brazilian, Uruguayan and Argentinean M. liza populations.

  11. Multiple invasions into freshwater by pufferfishes (teleostei: tetraodontidae): a mitogenomic perspective.

    PubMed

    Yamanoue, Yusuke; Miya, Masaki; Doi, Hiroyuki; Mabuchi, Kohji; Sakai, Harumi; Nishida, Mutsumi

    2011-02-25

    Pufferfishes of the Family Tetraodontidae are the most speciose group in the Order Tetraodontiformes and mainly inhabit coastal waters along continents. Although no members of other tetraodontiform families have fully discarded their marine lives, approximately 30 tetraodontid species spend their entire lives in freshwaters in disjunct tropical regions of South America, Central Africa, and Southeast Asia. To investigate the interrelationships of tetraodontid pufferfishes and thereby elucidate the evolutionary origins of their freshwater habitats, we performed phylogenetic analysis based on whole mitochondrial genome sequences from 50 tetraodontid species and closely related species (including 31 newly determined sequences). The resulting phylogenies reveal that the family is composed of four major lineages and that freshwater species from the different continents are independently nested in two of the four lineages. A monophyletic origin of the use of freshwater habitats was statistically rejected, and ancestral habitat reconstruction on the resulting tree demonstrates that tetraodontids independently entered freshwater habitats in different continents at least three times. Relaxed molecular-clock Bayesian divergence time estimation suggests that the timing of these invasions differs between continents, occurring at 0-10 million years ago (MA) in South America, 17-38 MA in Central Africa, and 48-78 MA in Southeast Asia. These timings are congruent with geological events that could facilitate adaptation to freshwater habitats in each continent.

  12. Occipito-vertebral fusion in ocean sunfishes (Teleostei: Tetraodontiformes: Molidae) and its phylogenetic implications.

    PubMed

    Britz, Ralf; Johnson, G David

    2005-10-01

    We describe the ontogeny of the occipital skull and anterior vertebrae of the molids Ranzania laevis and Masturus lanceolatus and compare it with that of the ostraciid Lactophrys sp. The first vertebra fuses to the basioccipital in early ontogeny in the two molids and previous authors thus confused that vertebra with the back of the basioccipital, so that all previous counts of their vertebral numbers are incorrect by one vertebra. As evidenced by Lactophrys sp., ostraciids are the only other tetraodontiforms with similar occipito-vertebral fusion. In contrast to the molids, additional anterior vertebrae fuse with this complex in ostraciids. We conclude that the shared occipito-vertebral fusion in molids and ostraciids and its otherwise extremely rare occurrence among teleosts provide support for a sister-group relationship of the two families.

  13. Fluctuating asymmetry as a pollution monitor: The Australian estuarine smooth toadfish Tetractenos glaber (Teleostei: Tetraodontidae).

    PubMed

    Lajus, Dmitry; Yurtseva, Anastasia; Birch, Gavin; Booth, David J

    2015-12-30

    The relationship between pollution level in estuarine sediment and fluctuating asymmetry (FA) of resident smooth toadfish Tetractenos glaber was evaluated. A total of 188 fish from Sydney and Hawkesbury River estuaries (5 locations from each) were analysed for 28 bilateral skull bone characters. Sediment pollution was quantified based on analysis of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) and organochlorine pesticides (DDT, DDD, DDE, chlordane, dieldrin, lindane). Sediment toxicity was characterized using the mean quotient approach (MERMQ) and ranged from low to moderate level for heavy metals and from low to severe for organochlorides. The mean shape and directional asymmetry of fish bones differed among locations, suggesting a response to local environments. FA was positively correlated with organochlorine pesticides across locations, but not with heavy metals. These results suggest that fish FA could be a useful estimator of stress caused by organic toxicity based on the MERMQ approach.

  14. Stone loaches of Choman River system, Kurdistan, Iran (Teleostei: Cypriniformes: Nemacheilidae).

    PubMed

    Kamangar, Barzan Bahrami; Prokofiev, Artem M; Ghaderi, Edris; Nalbant, Theodore T

    2014-01-20

    For the first time, we present data on species composition and distributions of nemacheilid loaches in the Choman River basin of Kurdistan province, Iran. Two genera and four species are recorded from the area, of which three species are new for science: Oxynoemacheilus kurdistanicus, O. zagrosensis, O. chomanicus spp. nov., and Turcinoemacheilus kosswigi Băn. et Nalb. Detailed and illustrated morphological descriptions and univariate and multivariate analysis of morphometric and meristic features are for each of these species. Forty morphometric and eleven meristic characters were used in multivariate analysis to select characters that could discriminate between the four loach species. Discriminant Function Analysis revealed that sixteen morphometric measures and five meristic characters have the most variability between the loach species. The dendrograms based on cluster analysis of Mahalanobis distances of morphometrics and a combination of both characters confirmed two distinct groups: Oxynoemacheilus spp. and T. kosswigi. Within Oxynoemacheilus, O. zagrosensis and O. chomanicus are more similar to one other rather to either is to O. kurdistanicus.

  15. Eidinemacheilus proudlovei, a new subterranean loach from Iraqi Kurdistan (Teleostei; Nemacheilidae).

    PubMed

    Freyhof, Jörg; Abdullah, Younis Sabir; Ararat, Korsh; Ibrahim, Hamad; Geiger, Matthias F

    2016-10-04

    Eidinemacheilus proudlovei, new species, is described from subterranean waters in the Little Zab River drainage in Iraqi Kurdistan. After the discovery of E. smithi in 1976, E. proudlovei is the second troglomorphic nemacheilid loach found in the Middle East and the second species placed in Eidinemacheilus. Eidinemacheilus proudlovei is distinguished from E. smithi by having 8+8 or 8+7 branched caudal-fin rays, no adipose keel on the caudal peduncle, enlarged jaws and a fully developed head canal system. It furthers differs substantially in its DNA barcode (>8% K2P distance) from all other nemacheilid loaches in the Middle East, Europe and Western India.

  16. Muscular system in the pacific bluefin tuna Thunnus orientalis (Teleostei: Scombridae).

    PubMed

    Nakae, Masanori; Sasaki, Kunio; Shinohara, Gento; Okada, Tokihiko; Matsuura, Keiichi

    2014-02-01

    The muscular system in the Pacific bluefin tuna Thunnus orientalis is studied in detail. For the first time, a complete description of the muscular anatomy of a thunnid is provided here. Eighty-two elements including subdivisions of components of the muscular system are identified. This is less than found in a basal perciform and two other investigated scombrid species, owing mainly to the absence or fusion of pectoral, pelvic and caudal fin muscles. The absence of elements of the basal perciform pattern was most prominent in the caudal fin, which includes only the flexor dorsalis, flexor ventralis, hypochordal longitudinalis, and interradialis. In the caudal fin, the medial fan-shaped ray was identified as the first dorsal ray, judging from myological and neuroanatomical characters. The highly developed gill filament muscles in Thunnus orientalis and sheet-like rectus communis control gill ventilation. Long body muscle tendons reduce the metabolic energy needed during rapid and continuous swimming. These characters are interpreted as adaptations in the context of the oceanic life style of the species.

  17. Phylogenetic relationships of the algae scraping cyprinid genus Capoeta (Teleostei: Cyprinidae).

    PubMed

    Levin, Boris A; Freyhof, Jörg; Lajbner, Zdeněk; Perea, Silvia; Abdoli, Asghar; Gaffaroğlu, Muhammet; Ozuluğ, Müfit; Rubenyan, Haikaz R; Salnikov, Vladimir B; Doadrio, Ignacio

    2012-01-01

    We reconstructed the matrilineal phylogeny of Asian algae-eating fishes of the genus Capoeta based on complete mitochondrial gene for cytochrome b sequences obtained from 20 species sampled from the majority of the range and 44 species of closely related barbs of the genera Barbus s. str. and Luciobarbus. The results of this study show that Capoeta forms a strongly supported monophyletic subclade nested within the Luciobarbus clade, suggesting that specialized scraping morphology appeared once in the evolutionary history of the genus. We detected three main groups of Capoeta: the Mesopotamian group, which includes three species from the Tigris-Euphrates system and adjacent water bodies, the Anatolian-Iranian group, which has the most diversified structure and encompasses many species distributed throughout Anatolian and Iranian inland waters, and the Aralo-Caspian group, which consists of species distributed in basins of the Caspian and Aral Seas, including many dead-end rivers in Central Asia and Northern Iran. The most probable origination pathway of the genus Capoeta is hypothesized to occur as a result of allopolyploidization. The origin of Capoeta was found around the Langhian-Serravallian boundary according to our molecular clock. The diversification within the genus occurred along Middle Miocene-Late Pliocene periods.

  18. Multiple colonisations of the Lake Malawi catchment by the genus Opsaridium (Teleostei: Cyprinidae).

    PubMed

    Sungani, Harold; Ngatunga, Benjamin P; Koblmüller, Stephan; Mäkinen, Tuuli; Skelton, Paul H; Genner, Martin J

    2017-02-01

    It has been proposed that the fish faunas of African rivers assemble through multiple colonisation events, while lake faunas form additionally through intralacustine speciation. While this pattern has been established for many lineages, most notably cichlids, there are opportunities to further investigate the concept using phylogenies of congeneric endemic species within ancient lake catchments. The Lake Malawi catchment contains three river-spawning cyprinids of the genus Opsaridium, two of which are endemic. These species differ in body size, migratory behaviour and habitat use, but it has never previously been tested if these represent a monophyletic radiation, or have instead colonised the lake independently. We placed these species in a broader phylogeny of Opsaridium and the related genus Raiamas, including all known species from the river systems surrounding Lake Malawi. Our results suggest that each of the species has independently colonised the lake catchment, with all three taxa having well-defined sister taxa outside of the lake, and all sharing a common ancestor ∼14.9million years ago, before the Lake Malawi basin started to form ∼8.6million years ago. Additionally, the results strongly support previous observations that Opsaridium is not a monophyletic group, but instead contains Raiamas from the Congo drainage. Together these results are supportive of the concept that river fish faunas within African catchments are primarily assembled through a process of accumulation from independent origins, rather than within-catchment speciation and adaptive radiation. In light of these results we also suggest there is scope for a re-evaluation of systematics of both Opsaridium and Raiamas.

  19. A new species of Didogobius (Teleostei: Gobiidae) from the Canary Islands.

    PubMed

    Van Tassell, James L; Kramer, Annemarie

    2014-05-01

    Didogobius helenae is described from the Canary Islands. It has a sensory papillae pattern that is consistent with the current diagnosis for Didogobius, but lacks all head canals and pores that are present in other members of the genus. Pores, in general, are replaced by large papillae.  The species is defined by first dorsal fin VI; second dorsal fin I,10; anal fin I,9; pectoral fin 16-17; pelvic fin I,5 and disk shaped; lateral scales 28-30, cycloid at anterior, becoming ctenoid posteriorly; cycloid scales present on belly and posterior breast; predorsal region, cheek, operculum and base of pectoral fin without scales; lower most scale on the caudal fin-base with elongate, thickened ctenii along the upper and lower posterior edges. Color in life consists of four mottled, wide brown-orange bars separated by narrower white bars on the trunk, the cheek whitish with 5 more or less circular blotches of orange, outlined in dark brown and a black spot on ventral operculum. A key to the species is provided. 

  20. The eyes of lanternfishes (Myctophidae, Teleostei): novel ocular specializations for vision in dim light.

    PubMed

    de Busserolles, Fanny; Marshall, N Justin; Collin, Shaun P

    2014-05-01

    Lanternfishes are one of the most abundant groups of mesopelagic fishes in the world's oceans and play a critical role in biomass vertical turnover. Despite their importance, very little is known about their physiology or how they use their sensory systems to survive in the extreme conditions of the deep sea. In this study, we provide a comprehensive description of the general morphology of the myctophid eye, based on analysis of 53 different species, to understand better their visual capabilities. Results confirm that myctophids possess several visual adaptations for dim-light conditions, including enlarged eyes, an aphakic gap, a tapetum lucidum, and a pure rod retina with high densities of long photoreceptors. Two novel retinal specializations were also discovered. The first specialization is a fundal pigmentation in adult eyes, found within an isolated retinal region (typically central retina) composed of modified pigment epithelial cells, which we hypothesize to be the remnant of a more pronounced visual specialization important in larval stages. The second specialization is an aggregation of extracellular microtubular-like structures found within the sclerad region of the inner nuclear layer of the retina. We hypothesize that the marked interspecific differences in the hypertrophy of these microtubular-like structures may be related to inherent differences in visual function. A general interspecific variability in other parts of the eye is also revealed and examined in this study. The contribution of both ecology and phylogeny to the evolution of ocular specializations and vision in dim light are discussed.

  1. The complete mitogenome of the river blackfish, Gadopsis marmoratus (Richardson, 1848) (Teleostei: Percichthyidae).

    PubMed

    Gan, Han Ming; Tan, Mun Hua; Lee, Yin Peng; Austin, Christopher M

    2016-05-01

    The mitogenome of the Australian freshwater blackfish, Gadopsis marmoratus was recovered coverage by genome skimming using the MiSeq sequencer (GenBank Accession Number: NC_024436). The blackfish mitogenome has 16,407 base pairs made up of 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs, and a 819 bp non-coding AT-rich region. This is the 5th mitogenome sequence to be reported for the family Percichthyidae.

  2. Evolutionary history of asexual hybrid loaches (Cobitis: Teleostei) inferred from phylogenetic analysis of mitochondrial DNA variation.

    PubMed

    Janko, K; Kotlík, P; Ráb, P

    2003-11-01

    Reconstruction of the evolutionary history of asexual lineages undermines their suitability as models for the studies of evolutionary consequences of sexual reproduction. Using molecular tools we addressed the origin, age and maternal ancestry of diploid and triploid asexual lineages arisen through the hybridization between spiny loaches Cobitis elongatoides, C. taenia and C. tanaitica. Reconstructions of the phylogenetic relationships among mitochondrial DNA (mtDNA) haplotypes, revealed by sequence analyses, suggest that both hybrid complexes (C. elongatoides-taenia and C. elongatoides-tanaitica) contained several asexual lineages of independent origin. Cobitis elongatoides was the exclusive maternal ancestor of all the C. elongatoides-tanaitica hybrids, whereas within the C. elongatoides-taenia complex, hybridization was reciprocal. In both complexes the low haplotype divergences were consistent with a recent origin of asexual lineages. Combined mtDNA and allozyme data suggest that the triploids arose through the incorporation of a haploid sperm genome into unreduced ova produced by diploid hybrids.

  3. Molecular Evidence for Multiple Origins of the European Spined Loaches (Teleostei, Cobitidae)

    PubMed Central

    Perdices, Anabel; Bohlen, Joerg; Šlechtová, Vendula; Doadrio, Ignacio

    2016-01-01

    We present a phylogenetic investigation of the Northern Clade, the major monophyletic clade within the freshwater fish family Cobitidae, one of the most prominent families of freshwater fishes found in Asian and European waters. Phylogenetic reconstructions based on the cytochrome b and RAG-1 genes show the genera Microcobitis, Sabanejewia, Koreocobitis and Kichulchoia as monophyletic groups. These reconstructions also show a Cobitis sensu lato and a Misgurnus sensu lato group. The Cobitis sensu lato group includes all species of Cobitis, Iksookimia, Niwaella and Kichulchoia, while the Misgurnus sensu lato group includes Misgurnus, Paramisgurnus and Koreocobitis. Although the monophyly of both the Cobitis sensu lato and Misgurnus sensu lato groups is supported, relationships within the groups are incongruent with current generic definitions. The absence of monophyly of most genera included in the Cobitis sensu lato group (Cobitis, Iksookimia and Niwaella) or their low genetic differentiation (Kichuchoia) supports their consideration as synonyms of Cobitis. Molecular phylogenies indicate that the Asian species of Misgurnus experienced a mitochondrial introgression from a lineage of Cobitis. We also find two nuclear haplotypes in the same Cobitis species from the Adriatic area that, in the absence of morphological differentiation, may indicate molecular introgression. Most lineages within the Northern Clade consist of species found in East Asia. However, some lineages also contain species from Europe and Asia Minor. The phylogenetic relationships presented here are consistent with previous studies suggesting an East Asian origin of the Northern Clade. According to the current distributions and phylogenetic relationships of the Misgurnus sensu lato and Cobitis clade lineages, particularly of M. fossilis and C. melanoleuca, the range expansion of East Asian species into Europe was most likely via Siberia into Northern and Central Europe. Phylogenetic analyses also show that the Cobitis sensu lato group consists of two clear subgroups (I and II), each presenting geographical differences. Subgroup I is distributed exclusively in East Asian drainages with an Eastern European offshoot (C. melanoleuca), whereas Subgroup II includes species widespread throughout Europe (including the Mediterranean), Asia Minor, the Black Sea and the Caucasus, with some lineages related to species restricted to East Asia. PMID:26727121

  4. Monogenean anchor morphometry: systematic value, phylogenetic signal, and evolution

    PubMed Central

    Soo, Oi Yoon Michelle; Tan, Wooi Boon; Lim, Lee Hong Susan

    2016-01-01

    Background. Anchors are one of the important attachment appendages for monogenean parasites. Common descent and evolutionary processes have left their mark on anchor morphometry, in the form of patterns of shape and size variation useful for systematic and evolutionary studies. When combined with morphological and molecular data, analysis of anchor morphometry can potentially answer a wide range of biological questions. Materials and Methods. We used data from anchor morphometry, body size and morphology of 13 Ligophorus (Monogenea: Ancyrocephalidae) species infecting two marine mugilid (Teleostei: Mugilidae) fish hosts: Moolgarda buchanani (Bleeker) and Liza subviridis (Valenciennes) from Malaysia. Anchor shape and size data (n = 530) were generated using methods of geometric morphometrics. We used 28S rRNA, 18S rRNA, and ITS1 sequence data to infer a maximum likelihood phylogeny. We discriminated species using principal component and cluster analysis of shape data. Adams’s Kmult was used to detect phylogenetic signal in anchor shape. Phylogeny-correlated size and shape changes were investigated using continuous character mapping and directional statistics, respectively. We assessed morphological constraints in anchor morphometry using phylogenetic regression of anchor shape against body size and anchor size. Anchor morphological integration was studied using partial least squares method. The association between copulatory organ morphology and anchor shape and size in phylomorphospace was used to test the Rohde-Hobbs hypothesis. We created monogeneaGM, a new R package that integrates analyses of monogenean anchor geometric morphometric data with morphological and phylogenetic data. Results. We discriminated 12 of the 13 Ligophorus species using anchor shape data. Significant phylogenetic signal was detected in anchor shape. Thus, we discovered new morphological characters based on anchor shaft shape, the length between the inner root point and the outer root

  5. [Detection of the mitochondrial DNA haplotype characteristic of the least cisco (Coregonus sardinella, Valenciennes, 1848) in the vendace (C. albula, Linnaeus, 1758) population of Vodlozero (the Baltic Sea basin)].

    PubMed

    Borovikova, E A; Makhrov, A A

    2009-01-01

    Analysis of the nucleotide sequence of the mitochondrial ND-1 gene in the vendace population in lake Vodlozero (the eastern part of the Baltic Sea basin) revealed a sequence variant that is closely related to that of the least cisco of Siberia (the Indigirka River). Thus, together with the results of morphological and allozyme analysis of this population performed earlier, the results obtained in this study are suggestive of the immigration of the least cisco to the Baltic Sea basin during the last glaciation.

  6. Migration of the curimbatá Prochilodus lineatus (Valenciennes, 1836) (Pisces, Prochilodontidae) at the waterfall "Cachoeira de Emas" of the Mogi-Guaçu river--São Paulo, Brazil.

    PubMed

    Capeleti, A R; Petrere, M

    2006-05-01

    In this paper, we counted the ascending curimbatás at the fish ladder at the Cachoeira de Emas from October, 1992 to September, 1993 in one whole day (24 h period) per month at different observation points in the dam for 5 min every hour. Most of the fish (80%) were counted not in the fish ladder itself, but in two adjacent spillways at its left, perhaps due to the comparatively increased flow as they are narrower than the ladder. The bulk of the migration occurred in September/October. We inspected the degree of injury of the fish in order to examine the hypothesis that larger fish are less injured, however no conclusion was reached. The degree of injury varied between different points and in different months of the year.

  7. Evolutionary history of Otophysi (Teleostei), a major clade of the modern freshwater fishes: Pangaean origin and Mesozoic radiation

    PubMed Central

    2011-01-01

    Background Freshwater harbors approximately 12,000 fish species accounting for 43% of the diversity of all modern fish. A single ancestral lineage evolved into about two-thirds of this enormous biodiversity (≈ 7900 spp.) and is currently distributed throughout the world's continents except Antarctica. Despite such remarkable species diversity and ubiquity, the evolutionary history of this major freshwater fish clade, Otophysi, remains largely unexplored. To gain insight into the history of otophysan diversification, we constructed a timetree based on whole mitogenome sequences across 110 species representing 55 of the 64 families. Results Partitioned maximum likelihood analysis based on unambiguously aligned sequences (9923 bp) confidently recovered the monophyly of Otophysi and the two constituent subgroups (Cypriniformes and Characiphysi). The latter clade comprised three orders (Gymnotiformes, Characiformes, Siluriformes), and Gymnotiformes was sister to the latter two groups. One of the two suborders in Characiformes (Characoidei) was more closely related to Siluriformes than to its own suborder (Citharinoidei), rendering the characiforms paraphyletic. Although this novel relationship did not receive strong statistical support, it was supported by analyzing independent nuclear markers. A relaxed molecular clock Bayesian analysis of the divergence times and reconstruction of ancestral habitats on the timetree suggest a Pangaean origin and Mesozoic radiation of otophysans. Conclusions The present timetree demonstrates that survival of the ancestral lineages through the two consecutive mass extinctions on Pangaea, and subsequent radiations during the Jurassic through early Cretaceous shaped the modern familial diversity of otophysans. This evolutionary scenario is consistent with recent arguments based on biogeographic inferences and molecular divergence time estimates. No fossil otophysan, however, has been recorded before the Albian, the early Cretaceous 100-112 Ma, creating an over 100 million year time span without fossil evidence. This formidable ghost range partially reflects a genuine difference between the estimated ages of stem group origin (molecular divergence time) and crown group morphological diversification (fossil divergence time); the ghost range, however, would be filled with discoveries of older fossils that can be used as more reasonable time constraints as well as with developments of more realistic models that capture the rates of molecular sequences accurately. PMID:21693066

  8. Marine-freshwater transitions are associated with the evolution of dietary diversification in terapontid grunters (Teleostei: Terapontidae).

    PubMed

    Davis, A M; Unmack, P J; Pusey, B J; Johnson, J B; Pearson, R G

    2012-06-01

    The ecological opportunities associated with transitions across the marine-freshwater interface are regarded as an important catalyst of diversification in a range of aquatic taxa. Here, we examined the role of these major habitat transitions and trophic diversification in a radiation of Australasian fishes using a new molecular phylogeny incorporating 37 Terapontidae species. A combined mitochondrial and nuclear gene analysis yielded a well-supported tree with most nodes resolved. Ancestral terapontids appear to have been euryhaline in habitat affiliation, with a single transition to freshwater environments producing all Australasian freshwater species. Mapping of terapontid feeding modes onto the molecular phylogeny-predicted carnivorous dietary habits was displayed by ancestral terapontids, which subsequently diversified into a range of additional carnivorous, omnivorous, herbivorous and detritivorous dietary modes upon transition to freshwater habitats. Comparative analyses suggested that following the freshwater invasion, the single freshwater clade has exhibited an increased rate of diversification at almost three times the background rate evident across the rest of the family. The marine-freshwater transition within Terapontidae appears to have resulted in substantial dietary radiation in freshwater environments, as well as increased lineage diversification rates relative to euryhaline-marine habitats.

  9. Mapping the potential distribution of the invasive Red Shiner, Cyprinella lutrensis (Teleostei: Cyprinidae) across waterways of the conterminous United States

    USGS Publications Warehouse

    Poulos, Helen M.; Chernoff, Barry; Fuller, Pam L.; Butman, David

    2012-01-01

    Predicting the future spread of non-native aquatic species continues to be a high priority for natural resource managers striving to maintain biodiversity and ecosystem function. Modeling the potential distributions of alien aquatic species through spatially explicit mapping is an increasingly important tool for risk assessment and prediction. Habitat modeling also facilitates the identification of key environmental variables influencing species distributions. We modeled the potential distribution of an aggressive invasive minnow, the red shiner (Cyprinella lutrensis), in waterways of the conterminous United States using maximum entropy (Maxent). We used inventory records from the USGS Nonindigenous Aquatic Species Database, native records for C. lutrensis from museum collections, and a geographic information system of 20 raster climatic and environmental variables to produce a map of potential red shiner habitat. Summer climatic variables were the most important environmental predictors of C. lutrensis distribution, which was consistent with the high temperature tolerance of this species. Results from this study provide insights into the locations and environmental conditions in the US that are susceptible to red shiner invasion.

  10. Pluvial Drainage Patterns and Holocene Desiccation Influenced the Genetic Architecture of Relict Dace, Relictus solitarius (Teleostei: Cyprinidae)

    PubMed Central

    Houston, Derek D.; Evans, R. Paul; Shiozawa, Dennis K.

    2015-01-01

    Changing drainage patterns have played a significant role in the evolution of western North American aquatic taxa. Relict dace, Relictus solitarius, is a Great Basin endemic cyprinid with a native range that is restricted to four valleys in eastern Nevada. Relictus solitarius now occupies spring systems that are the remnants of Pleistocene-era pluvial lakes, although it may have occurred in the area for much longer. Here we use mitochondrial DNA sequence data to assess range-wide genetic diversity of R. solitarius, and to estimate divergence times to determine whether pluvial drainages played an important role in shaping intraspecific genetic diversity. Genetic diversification within R. solitarius began during the early to mid-Pleistocene, separating populations within two sets of valleys (Butte/Ruby and Goshute/Steptoe). Additional diversification in each of the two sets of valleys occurred more recently, in the mid- to late-Pleistocene. Holocene desiccation has further isolated populations, and each population sampled contains unique mtDNA haplotypes. Pluvial drainage patterns did contribute to the genetic structure observed within R. solitarius, but most of the intraspecific diversification does not appear to be associated with the Last Glacial Maximum. Holocene desiccation has also contributed to the observed genetic structure. The relict dace populations we sampled are all unique, and we recommend that future management efforts should strive to preserve as much of the genetic diversity as possible. PMID:26394395

  11. Otolith morphology and hearing abilities in cave- and surface-dwelling ecotypes of the Atlantic molly, Poecilia mexicana (Teleostei: Poeciliidae)

    PubMed Central

    Schulz-Mirbach, Tanja; Ladich, Friedrich; Riesch, Rüdiger; Plath, Martin

    2010-01-01

    Cave fish have rarely been investigated with regard to their inner ear morphology, hearing abilities, and acoustic communication. Based on a previous study that revealed morphological differences in the saccular otolith between a cave and two surface populations of Poecilia mexicana, we checked for additional differences in utricular and lagenar otoliths and tested whether different populations have similar hearing sensitivities. We found pronounced differences in the shape of all three otoliths. Otoliths of the saccule and lagena from cave fish differed from those of surface fish in the features of the face oriented towards the sensory epithelium. In addition, otoliths of the utricle and lagena were significantly heavier in cave fish. Auditory sensitivities were measured between 100 and 1500 Hz, utilizing the auditory evoked potential recording technique. We found similar hearing abilities in cave and surface fish, with greatest sensitivity between 200 and 300 Hz. An acoustic survey revealed that neither ecotype produced species-specific sounds. Our data indicate that cave dwelling altered the otolith morphology in Atlantic mollies, probably due to metabolic differences. Different otolith morphology, however, did not affect general auditory sensitivity or acoustic behavior. PMID:20430090

  12. Phylogeny and biogeography of 91 species of heroine cichlids (Teleostei: Cichlidae) based on sequences of the cytochrome b gene.

    PubMed

    Pérez, Gustavo A Concheiro; Rícan, Oldrich; Ortí, Guillermo; Bermingham, Eldredge; Doadrio, Ignacio; Zardoya, Rafael

    2007-04-01

    Heroini constitute the second largest tribe of Neotropical cichlids and show their greatest diversity in Mesoamerica. Although heroine species are morphologically and ecologically very diverse, they were all historically assigned to one single genus, Cichlasoma that was never formally revised from a phylogenetic point of view. Here, we present the most comprehensive molecular phylogeny of the tribe Heroini to date, based on the complete DNA sequence of the mitochondrial gene cytochrome b, and the analysis of 204 individuals representing 91 species. Phylogenetic analyses did not support the monophyly of heroines because the genus Pterophyllum was placed as the sister group of all remaining heroines plus cichlasomatines. However, the recovered relative position of Pterophyllum was without strong statistical support. Within the remaining heroines, Hyspelecara and Hoplarchus are recovered with low support in a basal position with respect to a clade that includes Heros, Uaru, Mesonauta, and Symphysodon, and the circumamazonian (CAM) heroines. The first clade is restricted to South America. The largest clade of heroines, the CAM heroines, include more than 85% of the species within the tribe. This clade is mostly Mesoamerican, but also contains four species found in the Greater Antilles (Nandopsis), and three genera found in South America (the 'Heros' festae group, Australoheros, and Caquetaia). Up to eight major lineages can be recovered within the CAM heroines, but the phylogenetic relationships among them remain unresolved. Two large suprageneric groups can be distinguished, the amphilophines and the herichthyines. The amphilophines include Amphilophus, Archocentrus, Hypsophrys, Neetroplus, Parachromis, Petenia, and five additional unnamed genera (the 'Heros' istlanus group, the 'Amphilophus' calobrensis group, the 'Heros' urophthalmus group, the 'Heros' wesseli group, and the 'Heros' sieboldii group). The herichthyines include the crown-group herichthyines (Herichthys, Theraps, Vieja, and Paratheraps) and the genera Tomocichla, Herotilapia, and Thorichthys, together with three unnamed genera (the 'Heros' umbriferus group, the 'Heros' grammodes group, and the 'Heros' salvini group). Amphilophines are prevalent in southern Mesomerica south of the Motagua fault. Herichthyines have basal linages in Central America, whereas crown-group herichthyines and three related genera are found north from the Motagua fault. At least two independent origins are required to explain current Mesoamerican heroine distribution. Dispersal of heroines from South America into Mesoamerica was dated between 24 and 16 million years ago (MYA) based on geological calibrations and on standard fish mitochondrial cytochrome b rates, respectively. These datings cannot be reconciled with currently known geological evidence, and the existence of a connection between Central America and South America in the Miocene needs to be postulated in order to explain the origins of Mesoamerican heroine lineages. However, our datings agree with those estimated for the dispersal of other secondary freshwater fishes (Rivulidae, Synbranchus) into Mesoamerica, and predate the invasion of primary freshwater fishes by at least 10 myr.

  13. Male mate choice and sperm allocation in a sexual/asexual mating complex of Poecilia (Poeciliidae, Teleostei)

    PubMed Central

    Schlupp, I; Plath, M

    2005-01-01

    Male mate choice is critical for understanding the evolution and maintenance of sexual/asexual mating complexes involving sperm-dependent, gynogenetic species. Amazon mollies (Poecilia formosa) require sperm to trigger embryogenesis, but the males (e.g. Poecilia mexicana) do not contribute genes. Males benefit from mating with Amazon mollies, because such matings make males more attractive to conspecific females, but they might control the cost of such matings by providing less sperm to Amazon mollies. We examined this at the behavioural and sperm levels. P. mexicana males preferred to mate with, and transferred more sperm to conspecific females. However, if males mated with P. formosa, sperm was readily transferred. This underscores the importance of male choice in this system. PMID:17148157

  14. Clinal variation at microsatellite loci reveals historical secondary intergradation between glacial races of Coregonus artedi (Teleostei: Coregoninae).

    PubMed

    Turgeon, J; Bernatchez, L

    2001-11-11

    Classical models of the spatial structure of population genetics rely on the assumption of migration-drift equilibrium, which is seldom met in natural populations having only recently colonized their current range (e.g., postglacial). Population structure then depicts historical events, and counfounding effects due to recent secondary contact between recently differentiated lineages can further counfound analyses of association between geographic and genetic distances. Mitochondrial polymorphisms have revealed the existence of two closely related lineages of the lake cisco, Coregonus artedi, whose significantly different but overlaping geographical distributions provided a weak signal of past range fragmentation blurred by putative subsequent extensive secondary contacts. In this study, we analyzed geographical patterns of genetic variation at seven microsatellite loci among 22 populations of lake cisco located along the axis of an area covered by proglacial lakes 12,000-8,000 years ago in North America. The results clearly confirmed the existence of two genetically distinct races characterized by different sets of microsatellite alleles whose frequencies varied clinally across some 3000 km. Equilibrium and nonequilibrium analyses of isolation by distance revealed historical signal of gene flow resulting from the nearly complete admixture of these races following neutral secondary contacts in their historical habitat and indicated that the colonization process occurred by a stepwise expansion of an eastern (Atlantic) race into a previously established Mississippian race. This historical signal of equilibrium contrasted with the current migration-drift disequilibrium within major extant watersheds and was apparently maintained by high effective population sizes and low migration regimes.

  15. Complete mitochondrial genome of Ptychobarbus kaznakovi (Teleostei: Cypriniformes: Cyprinidae), and repetitive sequences in the D-loop.

    PubMed

    Ma, Qingzhan; Wu, Bo; Li, Jiuxuan; Song, Zhaobin

    2016-05-01

    The complete mitochondrial DNA genome of Ptychobarbus kaznakovi was sequenced and characterized. The genome is 16,842 bp in length. Similar with most teleosts, it has two ribosomal RNA (rRNA) genes, 13 protein-coding genes, 22 transfer RNA (tRNA) genes, and one displacement loop (D-loop) region. Conserved sequence blocks, including ETAS, CSB-B, D, E, F, and CSB1-3, were identified in the D-loop, which is similar to other species in Cypriniformes. Nevertheless, a 55 bp tandem repeat array was also identified at 3' end of the D-loop, which is the first finding in Schizothoracinae. Phylogenetic analysis showed that the species of Ptychobarbus (P. dipogon and P. kaznakovi) formed a monophyletic group and represented close relationship to the species without scales in Schizothoracinae.

  16. A review of the glyptosternine catfish genus Exostoma Blyth 1860 from Thailand, with descriptions of two new species (Teleostei: Siluriformes).

    PubMed

    Ng, Heok Hee; Vidthayanon, Chavalit

    2014-10-02

    We review members of the sisorid catfish genus Exostoma known from Thailand. Three species are recognized, of which two from the headwaters of the Chao Phraya River drainage in northwestern Thailand, are described here as new: E. effrenum and E. peregrinator. In addition to the two new species, E. berdmorei (which is here redescribed) is also known from the Salween River drainage in western Thailand. The three species can be distinguished from each other and other congeners by the morphologies of the adipose and caudal fins, as well as morphometric data for the eye diameter, head width, dorsal-to-adipose distance, body depth at anus, caudal-peduncle length, caudal-peduncle depth, and numbers of branched pectoral-fin rays and preanal vertebrae. 

  17. Molecular phylogeny of grunts (Teleostei, Haemulidae), with an emphasis on the ecology, evolution, and speciation history of New World species

    PubMed Central

    2012-01-01

    Background The fish family Haemulidae is divided in two subfamilies, Haemulinae and Plectorhynchinae (sweetlips), including approximately 17 genera and 145 species. The family has a broad geographic distribution that encompasses contrasting ecological habitats resulting in a unique potential for evolutionary hypotheses testing. In the present work we have examined the phylogenetic relationships of the family using selected representatives of additional Percomorpha based on Bayesian and Maximum likelihood methods by means of three mitochondrial genes. We also developed a phylogenetic hypothesis of the New World species based on five molecular markers (three mitochondrial and two nuclear) as a framework to evaluate the evolutionary history, the ecological diversification and speciation patterns of this group. Results Mitochondrial genes and different reconstruction methods consistently recovered a monophyletic Haemulidae with the Sillaginidae as its sister clade (although with low support values). Previous studies proposed different relationships that were not recovered in this analysis. We also present a robust molecular phylogeny of Haemulinae based on the combined data of two nuclear and three mitochondrial genes. All topologies support the monophyly of both sub-families (Haemulinae, Plectorhinchinae). The genus Pomadasys was shown to be polyphyletic and Haemulon, Anisotremus, and Plectorhinchus were found to be paraphyletic. Four of seven presumed geminate pairs were indeed found to be sister species, however our data did not support a contemporaneous divergence. Analyses also revealed that differential use of habitat might have played an important role in the speciation dynamics of this group of fishes, in particular among New World species where extensive sample coverage was available. Conclusions This study provides a new hypothesis for the sister clade of Hamulidae and a robust phylogeny of the latter. The presence of para- and polyphyletic genera underscores the need for a taxonomic reassessment within the family. A scarce sampling of the Old World Pomadasys species prevents us to definitively point to a New World origin of the sub-familiy Hamulinae, however our data suggest that this is likely to be the case. This study also illustrates how life history habitat influences speciation and evolutionary trajectories. PMID:22537107

  18. Goblet Cells and Mucus Types in the Digestive Intestine and Respiratory Intestine in Bronze Corydoras (Callichthyidae: Teleostei).

    PubMed

    Leknes, I L

    2015-10-01

    The structure and histochemical properties of the intestine in bronze corydoras (Corydoras aeneus), a stomach-containing teleost, are described, with emphasis on goblet cells and mucin types. The proximal intestine displayed a normal structure for teleosts, whereas the distal intestine was wide, translucent, thin-walled, richly vascularized and constantly filled with air, suggesting an important respiratory role. Goblet cells were common throughout the entire intestine and displayed a variable, but mainly faint metachromatic colour after toluidine blue. They were moderately coloured by alcian blue at both pH 2.5 and 0.2 and displayed no colour after periodic acid followed by Schiff's solution (PAS), but a distinct purple-brown colour after high iron diamine followed by alcian blue (pH 2.5). Together, these results suggest that the mucin in the intestine goblet cells consists mainly of sulphated proteoglycans. Further, the results from the present lectin and neuraminidase tests suggest that these mucins contain much N-acetylglucoseamines and some N-acetylgalactosamines and sialic acid, but seem to lack glucose and mannose. They also contain some galactose-N-acetylgalactosamines sequences, normally hidden by sialic acid. The distinct brush border and mucus layer on the epithelial cells in the respiratory intestine may indicate some digestive roles, such as absorption of water, ions and simple carbohydrates. As sulphated proteoglycans are tough and attract much water, this mucus may play important roles in the protection against mechanical and chemical damages and in the defence against micro-organisms throughout the entire intestine, but in the respiratory intestine it may impede significantly the oxygen uptake. However, as this part of the intestine usually contains no digesta, but is completely filled with air, frequently renewed by dry air from the atmosphere, and the main function of the mucus may be to protect the respiratory epithelium against a destroying and dangerous desiccation.

  19. Pluvial Drainage Patterns and Holocene Desiccation Influenced the Genetic Architecture of Relict Dace, Relictus solitarius (Teleostei: Cyprinidae).

    PubMed

    Houston, Derek D; Evans, R Paul; Shiozawa, Dennis K

    2015-01-01

    Changing drainage patterns have played a significant role in the evolution of western North American aquatic taxa. Relict dace, Relictus solitarius, is a Great Basin endemic cyprinid with a native range that is restricted to four valleys in eastern Nevada. Relictus solitarius now occupies spring systems that are the remnants of Pleistocene-era pluvial lakes, although it may have occurred in the area for much longer. Here we use mitochondrial DNA sequence data to assess range-wide genetic diversity of R. solitarius, and to estimate divergence times to determine whether pluvial drainages played an important role in shaping intraspecific genetic diversity. Genetic diversification within R. solitarius began during the early to mid-Pleistocene, separating populations within two sets of valleys (Butte/Ruby and Goshute/Steptoe). Additional diversification in each of the two sets of valleys occurred more recently, in the mid- to late-Pleistocene. Holocene desiccation has further isolated populations, and each population sampled contains unique mtDNA haplotypes. Pluvial drainage patterns did contribute to the genetic structure observed within R. solitarius, but most of the intraspecific diversification does not appear to be associated with the Last Glacial Maximum. Holocene desiccation has also contributed to the observed genetic structure. The relict dace populations we sampled are all unique, and we recommend that future management efforts should strive to preserve as much of the genetic diversity as possible.

  20. Phylogeographic, morphometric and taxonomic re-evaluation of the river sardine, Mesobola brevianalis (Boulenger, 1908) (Teleostei, Cyprinidae, Chedrini)

    PubMed Central

    Riddin, Megan A.; Bills, I. Roger; Villet, Martin H.

    2016-01-01

    Abstract The river sardine, Mesobola brevianalis (Boulenger, 1908), is the type species of Mesobola Howes, 1984. Standard phylogenetic analyses of partial sequences of the cytochrome oxidase I gene of individuals from populations across southern Africa that are currently identified as Mesobola brevianalis showed that these populations represent four genetically distinct allopatric lineages. Furthermore, Engraulicypris sardella (Günther, 1868), the type species of Engraulicypris Günther, 1894, was convincingly nested amongst these clades. These findings support synonymisation of Engraulicypris and Mesobola syn. n.; restoration of Engraulicypris gariepinus (Barnard, 1943), stat. rev. for the lower Orange River population; description of two new species, Engraulicypris ngalala sp. n. and Engraulicypris howesi sp. n. from the Rovuma and Kunene river systems, respectively; affirmation of the synonymy of Engraulicypris brevianalis (Boulenger, 1908), comb. n. sensu stricto and Engraulicypris whitei van der Horst, 1934; and restoration of Engraulicypris bredoi Poll, 1945, stat. rev. and Engraulicypris spinifer Bailey & Matthes, 1971, stat. rev. from Mesobola. Discriminant function analysis of a truss network of five traditional morphometric measurements and 21 morphometric measurements that characterised the shape of the fishes was used to seek morphological markers for the genetically distinct populations. Only Engraulicypris gariepinus was morphometrically distinctive, but live colouration differed between the lineages. Detailed taxonomic descriptions and an identification key for the species are provided. PMID:28138294

  1. A Ploidy Difference Represents an Impassable Barrier for Hybridisation in Animals. Is There an Exception among Botiid Loaches (Teleostei: Botiidae)?

    PubMed Central

    Bohlen, Jörg; Šlechtová, Vendula; Šlechta, Vlastimil; Šlechtová, Vera; Sember, Alexandr; Ráb, Petr

    2016-01-01

    One of the most efficient mechanisms to keep animal lineages separate is a difference in ploidy level (number of whole genome copies), since hybrid offspring from parents with different ploidy level are functionally sterile. In the freshwater fish family Botiidae, ploidy difference has been held responsible for the separation of its two subfamilies, the evolutionary tetraploid Botiinae and the diploid Leptobotiinae. Diploid and tetraploid species coexist in the upper Yangtze, the Pearl River and the Red River basins in China. Interestingly, the species ‘Botia’ zebra from the Pearl River basin combines a number of morphological characters that otherwise are found in the diploid genus Leptobotia with morphological characters of the tetraploid genus Sinibotia, therefore the aim of the present study is to test weather ‘B.’ zebra is the result of a hybridisation event between species from different subfamilies with different ploidy level. A closer morphological examination indeed demonstrates a high similarity of ‘B.’ zebra to two co-occurring species, the diploid Leptobotia guilinensis and the tetraploid Sinibotia pulchra. These two species thus could have been the potential parental species in case of a hybrid origin of ‘B.’ zebra. The morphologic analysis further reveals that ‘B.’ zebra bears even the diagnostic characters of the genera Leptobotia (Leptobotiinae) and Sinibotia (Botiinae). In contrast, a comparison of six allozyme loci between ‘B.’ zebra, L. guilinensis and S. pulchra showed only similarities between ‘B.’ zebra and S. pulchra, not between ‘B.’ zebra and L. guilinensis. Six specimens of ‘B.’ zebra that were cytogenetically analysed were tetraploid with 4n = 100. The composition of the karyotype (18% metacentric, 18% submetacentric, 36% subtelocentric and 28% acrocentric chromosomes) differs from those of L. guilinensis (12%, 24%, 20% and 44%) and S. pulchra (20%, 26%, 28% and 26%), and cannot be obtained by any combination of genomes from L. guilinensis and S. pulchra. Phylogenetic reconstructions based on sequence data of the mitochondrial cytochrome b gene and the nuclear RAG-1 gene invariably places ‘Botia’ zebra as sister species to S. pulchra, while L. guilinensis is only distantly related. The presented combination of genetic data demonstrates that ‘B.’ zebra is not the result of a hybridisation, but a species of tetraploid genus Sinibotia with a striking morphological evolution towards an enormous similarity with a co-occurring, but not directly related species. The complete lack of knowledge of the ecology of these species, their main predators or their ecological interactions hampers any conclusion regarding the evolutionary advantage of such adaptation. PMID:27442252

  2. Some aspects of the structural organization of the spinal cord of Gymnotus carapo (Teleostei, Gymnotiformes). I. The electromotor neurons.

    PubMed

    Trujillo-Cenoz, O; Echague, J A; Bertolotto, C; Lorenzo, D

    1986-01-01

    The spinal electromotor neurons (EMNs) of Gymnotus carapo from a distinct column dorsal to the central canal. When massively retrograde-labeled with horseradish peroxidase, these neurons show a well-developed dendritic arborization. Dendrites run along the longitudinal axis of the cord and also project toward the dorsal gray and dorsolateral funiculi. Input to the EMNs is mediated by scarce synaptic contacts which show the fine structural characteristics of the so-called "morphologically mixed" junctions. Serial section reconstructions of the junctional areas revealed the occurrence of "gap junctions," dense membranes facing cumuli of microvesicles, and relatively large zones of undifferentiated membranes. Comparative electrophysiological and morphological data suggest that EMN activity may be mediated by electrical transmission. Since neither dendro-dendritic nor dendro-somatic junctions have been observed, other circuitry alternatives are proposed to account for the expected synchronized firing of the EMNs.

  3. Karyotype and genome size of Iberochondrostoma almacai (Teleostei, Cyprinidae) and comparison with the sister-species I.lusitanicum

    PubMed Central

    2009-01-01

    This study aimed to define the karyotype of the recently described Iberian endemic Iberochondrostoma almacai, to revisit the previously documented chromosome polymorphisms of its sister species I.lusitanicum using C-, Ag-/CMA3 and RE-banding, and to compare the two species genome sizes. A 2n = 50 karyotype (with the exception of a triploid I.lusitanicum specimen) and a corresponding haploid chromosome formula of 7M:15SM:3A (FN = 94) were found. Multiple NORs were observed in both species (in two submetacentric chromosome pairs, one of them clearly homologous) and a higher intra and interpopulational variability was evidenced in I.lusitanicum. Flow cytometry measurements of nuclear DNA content showed some significant differences in genome size both between and within species: the genome of I. almacai was smaller than that of I.lusitanicum (mean values 2.61 and 2.93 pg, respectively), which presented a clear interpopulational variability (mean values ranging from 2.72 to 3.00 pg). These data allowed the distinction of both taxa and confirmed the existence of two well differentiated groups within I. lusitanicum: one that includes the populations from the right bank of the Tejo and Samarra drainages, and another that reunites the southern populations. The peculiar differences between the two species, presently listed as “Critically Endangered”, reinforced the importance of this study for future conservation plans. PMID:21637679

  4. Schistura sexnubes, a new diminutive river loach from the upper Mekong basin, Yunnan Province, China (Teleostei: Cypriniformes: Nemacheilidae)

    PubMed Central

    Endruweit, Marco

    2014-01-01

    An ichthyofaunistic survey of Mekong tributaries in Lincang Prefecture, Yunnan Province, China yielded a new species of nemacheilid loach, herein described as Schistura sexnubes species nova. The new species is readily distinguishable from its congeners by the following combination of characters: 8+8 branched caudal fin rays, an incomplete lateral line, a dissociated caudal bar, a shallow caudal peduncle depth (7.6%−9.6% SL; respectively caudal peduncle 1.76−1.95 times longer than deep), a diminutive size of less than 50 mm SL, and no sexual dimorphism. A dorsocephalic pattern consisting of a black, forward directed V-shaped formation located between the nares, and a white, ovoid blotch on the upper operculum serves as an autapomorphy. PMID:24470455

  5. Evolutionary history of the Lake Tanganyika cichlid tribe Lamprologini (Teleostei: Perciformes) derived from mitochondrial and nuclear DNA data

    PubMed Central

    Sturmbauer, Christian; Salzburger, Walter; Duftner, Nina; Schelly, Robert; Koblmüller, Stephan

    2010-01-01

    Lake Tanganyika comprises a cichlid species flock with substrate-breeding and mouthbrooding lineages. While sexual selection via mate choice on male mating color is thought to boost speciation rates in mouthbrooding cichlids, this is not the case in substrate-breeding lamprologines, which mostly form stable pairs and lack sexual dichromatism. We present a comprehensive reconstruction of the evolution of the cichlid tribe Lamprologini, based upon mtDNA sequences and multilocus nuclear DNA (AFLP) markers. Twelve mtDNA clades were identified, seven of which were corroborated by the AFLP tree. The radiation is likely to have started about 5.3 MYA, contemporarily with that of the mouthbrooding C-lineage, and probably triggered by the onset of deep-water conditions in Lake Tanganyika. Neither the Congo- nor the Malagarazi River species form the most ancestral branch. Several conflicts in the mtDNA phylogeny with taxonomic assignments based upon color, eco-morphology and behavior could be resolved and complemented by the AFLP analysis. Introgressive hybridization upon secondary contact seems to be the most likely cause for paraphyly of taxa due to mtDNA capture in species involving brood-care helpers, while accidental hybridization best explains the para- or polyphyly of several gastropod shell breeders. Taxonomic error or paraphyly due to the survival of ancestral lineages appear responsible for inconsistencies in the genera Lamprologus and Neolamprologus. PMID:20601006

  6. A new record of a flathead fish (Teleostei: Platycephalidae) from China based on morphological characters and DNA barcoding

    NASA Astrophysics Data System (ADS)

    Qin, Yan; Song, Na; Zou, Jianwei; Zhang, Zhaohui; Cheng, Guangping; Gao, Tianxiang; Zhang, Xiumei

    2013-05-01

    A new record of Platycephalus sp.1 (sensu Nakabo, 2002) was documented based on morphological characters and DNA barcoding. We collected 174 specimens of the genus Platycephalus from Chinese coastal waters of Dongying, Qingdao, Zhoushan, and Beihai. Samples were identified as Platycephalus sp.1 morphologically. The coloration, meristic traits, and morphometric measurements are consistent with previously published records. In brief, it is an orange-brown flathead fish with dark brown spots scattered on head and body, lateral line scales 83 to 99 with one or two spine-bearing anteriormost pored scale, no yellow blotch on the caudal fin. Cytochrome oxidase I subunit (COI) gene fragments were sequenced for phylogenetic analysis. The mean evolutionary distance within the species Platycephalus sp.1 was 0.1%. Net evolutionary distances between Platycephalus sp.1 and other species of Platycephalus ranged from 10.8% to 19.7%, which is much greater than the threshold for species delimitation. The COI sequence analysis strongly supports the validity of Platyceohalus sp.1 at genetic level.

  7. Varicus lacerta, a new species of goby (Teleostei, Gobiidae, Gobiosomatini, Nes subgroup) from a mesophotic reef in the southern Caribbean.

    PubMed

    Tornabene, Luke; Robertson, D Ross; Baldwin, Carole C

    2016-01-01

    We describe a new species of goby, Varicus lacerta sp. n., which was collected from a mesophotic reef at Curacao, southern Caribbean. The new species is the tenth species of Varicus, all of which occur below traditional SCUBA depths in the wider Caribbean area. Its placement in the genus Varicus is supported by a molecular phylogenetic analysis of three nuclear genes and the mitochondrial gene cytochrome b. In addition, the new species has one anal-fin pterygiophore inserted anterior to the first haemal spine, which distinguishes Varicus species from most species in the closely related and morphologically similar genus Psilotris. Varicus lacerta sp. n. is distinguished from all other named species of Varicus by the absence of scales, having highly branched, feather-like pelvic-fin rays, and in its live coloration. We provide the cytochrome c oxidase I DNA barcode of the holotype and compare color patterns of all species of Varicus and Psilotris for which color photographs or illustrations are available. This study is one of several recent studies demonstrating the utility of manned submersibles in exploring the diversity of poorly studied but species-rich deep-reef habitats.

  8. Two new deep-reef basslets (Teleostei, Grammatidae, Lipogramma), with comments on the eco-evolutionary relationships of the genus.

    PubMed

    Baldwin, Carole C; Robertson, D Ross; Nonaka, Ai; Tornabene, Luke

    2016-01-01

    The banded basslet, Lipogramma evides Robins & Colin, 1979, is shown to comprise two species: Lipogramma evides, which inhabits depths of 133-302 m, and a new species described here as Lipogramma levinsoni, which inhabits depths of 108-154 m and previously was considered to represent the juvenile of Lipogramma evides. A second new species of banded basslet, described here as Lipogramma haberi, inhabits depths of 152-233 m and was previously not reported in the literature. Morphologically, the three species differ in color patterns and modal numbers of gill rakers, whereas various other morphological features distinguish Lipogramma levinsoni from Lipogramma evides and Lipogramma haberi. DNA barcode data and multilocus, coalescent-based, species-delimitation analysis support the recognition of the three species. Phylogenetic analysis of mitochondrial and nuclear genetic data supports a sister-group relationship between the two deepest-living of the three species, Lipogramma evides and Lipogramma haberi, and suggests that the shallower Lipogramma levinsoni is more closely related to Lipogramma anabantoides Böhlke, 1960, which inhabits depths < 120 m. Evolutionary relationships within Lipogramma thus appear to be correlated with species depth ranges, an eco-evolutionary pattern that has been observed in other Caribbean marine teleosts and that warrants further investigation. The new species represent the eleventh and twelfth new fish species described in recent years from exploratory submersible diving in the Caribbean in the globally poorly studied depth zone of 50-300 m. This study suggests that there are at least two additional cryptic species of Lipogramma, which are being analyzed in ongoing investigations of Caribbean deep-reef ecosystems.

  9. Taxonomic review of the genus Trisopterus(Teleostei: Gadidae) with recognition of the capelan Trisopterus capelanus as a valid species.

    PubMed

    Delling, B; Noren, M; Kullander, S O; González, J A

    2011-11-01

    Trisopterus is demonstrated to be monophyletic, including four distinct species: T. capelanus, T. esmarkii, T. luscus and T. minutus. The capelan T. capelanus is resurrected from the synonymy of poor cod T. minutus, and is shown to be morphologically more similar to T. luscus, to which species it is also more closely related, indicated by a phylogenetic analysis presented here. A lectotype is designated for T. luscus. Trisopterus fasciatus, the type species of Trisopterus, is a junior synonym of T. luscus, and the lectotype of T. luscus is designated as the neotype of T. fasciatus. The lectotype of T. luscus is also designated as the neotype of Gadus barbatus. Gadus barbatus has priority over T. luscus but the name is suppressed by prevailing usage of T. luscus. A neotype is designated also for T. minutus. A phylogenetic analysis using mitochondrial cytochrome b, and a fragment of the nuclear rhodopsin gene, shows that T. capelanus and T. luscus are sister species, and in turn sister to a clade formed by T. minutus and T. esmarkii.

  10. Description of three new species of Moenkhausia (Teleostei, Characiformes, Characidae) with the definition of the Moenkhausia jamesi species complex.

    PubMed

    Petrolli, Marina G; Benine, Ricardo C

    2015-07-20

    From the examination of extensive comparative material currently identified as M. jamesi we verified that there are, at least, three new species under this name. These, along with M. jamesi and M. justae, form what we herein called the M. jamesi species complex, by sharing the following group of characters: a short maxilla, with its distal margin not exceeding anterior third of the second infraorbital; first through third teeth of the inner row of premaxilla and first and second dentary teeth with cusps arranged in a pronounced arch, humeral spot positioned between the fourth and seventh scales of the lateral line and extending up to four scale rows above the lateral line and one scale row below the lateral line, and a vertically oval to round spot at the base of the caudal fin rays. Moenkhausia ischyognatha sp. n., from Rio Xingu basin, differs from the other species of the complex by its lower head depth. Moenkhausia alesis sp. n., from the river system Tocantins-Araguaia, differs from M. jamesi, M. ischyognatha, and M. sthenosthoma by the number of scale rows above the lateral line. Moenkhausia sthenosthoma sp. n., from the Rio Madeira basin, differs from M. jamesi by the number of scale rows between the lateral line and the midventral scale series. Moenkhausia justae can be diagnosed from the other species of the complex by having a tri to pentacuspidate tooth on the maxilla.

  11. Species-level phylogeny of 'Satan's perches' based on discordant gene trees (Teleostei: Cichlidae: Satanoperca Günther 1862).

    PubMed

    Willis, Stuart C; López-Fernández, Hernán; Montaña, Carmen G; Farias, Izeni P; Ortí, Guillermo

    2012-06-01

    Neotropical rivers are home to the largest assemblage of freshwater fishes, but little is known about the phylogeny of these fishes at the species level using multi-locus molecular markers. Here, we present a phylogeny for all known species of the genus Satanoperca, a widespread group of Neotropical cichlid fishes, based on analysis of six unlinked genetic loci. To test nominal and proposed species limits for this group, we surveyed mtDNA sequence variation among 320 individuals representing all know species. Most nominal species were supported by this approach but we determined that populations in the Xingu, Tapajós, and Araguaia+Paraná Rivers are likely undescribed species, while S. jurupari and S. mapiritensis did not show clear genetic distinction. To infer a phylogeny of these putative species, we conducted maximum likelihood and Bayesian non-clock and relaxed clock analyses of concatenated data from three genes (one mitochondrial, two nuclear). We also used a multi-species coalescent model to estimate a species tree from six unlinked loci (one mitochondrial, five nuclear). The topologies obtained were congruent with other results, but showed only minimal to moderate support for some nodes, suggesting that more loci will be needed to satisfactorily estimate the distribution of coalescent histories within Satanoperca. We determined that this variation results from topological discordance among separate gene trees, likely due to differential sorting of ancestral polymorphisms.

  12. Cytogenetic analysis of B chromosomes in one population of the fish Moenkhausia sanctaefilomenae (Steindachner, 1907) (Teleostei, Characiformes)

    PubMed Central

    Voltolin, Diogo Teruo Hashimoto Tatiana Aparecida; Paes, Ana Danyelle Noitel Valim de Arruda; Foresti, Fausto; Bortolozzi, Jehud; Porto-Foresti, Fábio

    2012-01-01

    Abstract The aim of this study was to characterize cytogenetically one population of the fish Moenkhausia sanctaefilomenae (Steindachner, 1907), with emphasis on the analysis of B chromosomes. The nucleolar activity in the B microchromosomes was characterized, and an analysis of mitotic instability of these microchromosomes was accomplished. The results showed a diploid chromosome number of 50 chromosomes. In all individuals, we observed the presence of B microchromosomes with intra- and inter-individual variability. The analysis of the nucleolus organizing regions (NORs) by silver nitrate staining demonstrated multiple NORs. We observed active sites of ribosomal DNA in the B microchromosomes, with a frequency of 20% in the analyzed cells, which shows gene activity in these chromosomal elements. The analysis of constitutive heterochromatin patterns showed that the B microchromosomes are heterochromatic or euchromatic, which demonstrates differentiation of DNA composition between these genomic elements. The calculation of the mitotic instability index implied that B chromosomes in this species might be in a final stage of instability. PMID:24260658

  13. Phylogenetic relationships and biogeographical patterns in Circum-Mediterranean subfamily Leuciscinae (Teleostei, Cyprinidae) inferred from both mitochondrial and nuclear data

    PubMed Central

    2010-01-01

    Background Leuciscinae is a subfamily belonging to the Cyprinidae fish family that is widely distributed in Circum-Mediterranean region. Many efforts have been carried out to deciphering the evolutionary history of this group. Thus, different biogeographical scenarios have tried to explain the colonization of Europe and Mediterranean area by cyprinids, such as the "north dispersal" or the "Lago Mare dispersal" models. Most recently, Pleistocene glaciations influenced the distribution of leuciscins, especially in North and Central Europe. Weighing up these biogeographical scenarios, this paper constitutes not only the first attempt at deciphering the mitochondrial and nuclear relationships of Mediterranean leuciscins but also a test of biogeographical hypotheses that could have determined the current distribution of Circum-Mediterranean leuciscins. Results A total of 4439 characters (mitochondrial + nuclear) from 321 individuals of 176 leuciscine species rendered a well-supported phylogeny, showing fourteen main lineages. Analyses of independent mitochondrial and nuclear markers supported the same main lineages, but basal relationships were not concordant. Moreover, some incongruence was found among independent mitochondrial and nuclear phylogenies. The monophyly of some poorly known genera such as Pseudophoxinus and Petroleuciscus was rejected. Representatives of both genera belong to different evolutionary lineages. Timing of cladogenetic events among the main leuciscine lineages was gained using mitochondrial and all genes data set. Conclusions Adaptations to a predatory lifestyle or miniaturization have superimposed the morphology of some species. These species have been separated into different genera, which are not supported by a phylogenetic framework. Such is the case of the genera Pseudophoxinus and Petroleuciscus, which real taxonomy is not well known. The diversification of leuciscine lineages has been determined by intense vicariant events following the paleoclimatological and hydrogeological history of Mediterranean region. We propose different colonization models of Mediterranean region during the early Oligocene. Later vicariance events promoted Leuciscinae diversification during Oligocene and Miocene periods. Our data corroborate the presence of leuciscins in North Africa before the Messinian salinity crisis. Indeed, Messinian period appears as a stage of gradually Leuciscinae diversification. The rise of humidity at the beginning of the Pliocene promoted the colonization and posterior isolation of newly established freshwater populations. Finally, Pleistocene glaciations determined the current European distribution of some leuciscine species. PMID:20807419

  14. Biochemical responses over time in common carp Cyprinus carpio (Teleostei, Cyprinidae) during fed supplementation with α-lipoic acid.

    PubMed

    Enamorado, Alain D; Martins, Atila C; Flores, Juliana A; Tesser, Marcelo Borges; Caldas, Sergiane S; Primel, Ednei G; Monserrat, José Maria

    2015-10-01

    The current study aimed to evaluate the influence of lipoic acid (LA) supplementation (439.84±6.71 mg LA/kg feed) on antioxidants responses throughout the time in intestine, liver and muscle of juvenile common carp Cyprinus carpio. Two experimental groups were fed during four weeks with a diet with or without LA. Glutathione-S-transferase (GST) activity, glutathione (GSH) content, antioxidant capacity against peroxyl radicals (ACAP) and lipid peroxidation (TBARS) were evaluated in these organs. Also, a technique to measure protein disulfide bonds and sulfhydryl groups was optimized for intestine samples. GST activity was significantly higher (p<0.05) in intestine after two weeks of supplementation. GSH content was also significantly higher (p<0.05) in intestine, liver and muscle of fish fed with LA after two and three weeks, respectively. Total capacity antioxidant against peroxyl radicals was significantly increased (p<0.05) in the muscle of animals fed with LA after the fourth week. Concentration of disulfide bonds was higher in the intestine of fish fed with LA but this group also showed higher concentration of sulfhydryl groups (p<0.05). It is concluded that supplementation with LA is a safe strategy to induce antioxidant responses and improves the antioxidant status in different organs of common carp. Two week of supplementation are required to induce antioxidant responses in intestine and liver and three week for muscle.

  15. Cryptomyrus: a new genus of Mormyridae (Teleostei, Osteoglossomorpha) with two new species from Gabon, West-Central Africa.

    PubMed

    Sullivan, John P; Lavoué, Sébastien; Hopkins, Carl D

    2016-01-01

    We use mitochondrial and nuclear sequence data to show that three weakly electric mormyrid fish specimens collected at three widely separated localities in Gabon, Africa over a 13-year period represent an unrecognized lineage within the subfamily Mormyrinae and determine its phylogenetic position with respect to other taxa. We describe these three specimens as a new genus containing two new species. Cryptomyrus, new genus, is readily distinguished from all other mormyrid genera by a combination of features of squamation, morphometrics, and dental attributes. Cryptomyrus ogoouensis, new species, is differentiated from its single congener, Cryptomyrus ona, new species, by the possession of an anal-fin origin located well in advance of the dorsal fin, a narrow caudal peduncle and caudal-fin lobes nearly as long as the peduncle. In Cryptomyrus ona, the anal-fin origin is located only slightly in advance of the dorsal fin, the caudal peduncle is deep and the caudal-fin lobes considerably shorter than the peduncle. Continued discovery of new taxa within the "Lower Guinea Clade" of Mormyridae highlights the incompleteness of our knowledge of fish diversity in West-Central Africa. We present a revised key to the mormyrid genera of Lower Guinea.

  16. General characteristics of the diet of Trachinotus paitensis (Teleostei: Carangidae) from San Ignacio Lagoon, Baja California Sur, Mexico.

    PubMed

    Cruz Escalona, V H; Abitia Cárdenas, L A

    2004-03-01

    The food habits of Trachinotus paitensis, in San Ignacio Lagoon B.C.S., Mexico, were investigated. We observed that T. paitensis is carnivorous, feeding mainly on benthic invertebrates (the gastropods Anachis spp., Bittium spp., and the crustacean larvae). We concluded that T. paitensis is an opportunist predator that impacts mainly on epibenthic invertebrates.

  17. Ultrastructural study of the spermatozoon of Pronoprymna ventricosa (Digenea, Baccigerinae), parasite of the twaite shad Alosa fallax Lacepede (Pisces, Teleostei).

    PubMed

    Quilichini, Yann; Foata, Josephine; Marchand, Bernard

    2007-09-01

    In this paper, we describe the ultrastructural organisation of the spermatozoon of a Digenea Baccigerinae Pronoprymna ventricosa. This spermatozoon possesses the elements found in the others digeneans: two axonemes with 9 + "1" pattern, a mitochondrion, a nucleus, cortical microtubules and external ornamentations. However, this spermatozoon presents two particularities. The first is the presence of a single field of cortical microtubules disposed in the ventral side (mitochondrion side) of the spermatozoon. In the other digeneans, two fields of cortical microtubules are observed between the two axonemes. The second is the presence of external ornamentations not associated with cortical microtubules. These two points have, to our knowledge, never been described in another digenean. Moreover, a separation in two groups of the digenean spermatozoa is proposed in relation to the localisation of the external ornamentations. We propose to distinguish a first group exhibiting these elements in the proximal part of the spermatozoon and a second one with external ornamentations in a second part of the gamete.

  18. Taste preferences and taste thresholds to classical taste substances in the carnivorous fish, kutum Rutilus frisii kutum (Teleostei: Cyprinidae).

    PubMed

    Goli, Sheyda; Jafari, Valiollah; Ghorbani, Rassol; Kasumyan, Alexander

    2015-03-01

    The objective of this study was to compare the taste preferences in the closely related sympatric fish species with different feeding patterns. For this purpose, palatability for four classical taste substances was evaluated for carnivorous kutum Rutilus frisii kutum and the results were compared with the taste preferences of the omnivorous roach Rutilus rutilus which had been studied earlier. In addition, the threshold concentration and the dose-response relationship of the most palatable tastants were evaluated and the ability of kutum to differentiate food with tastants in different concentrations was estimated. It was found that citric acid significantly increases the agar gel pellet consumption within the range of concentrations from 0.01M to 0.52M; the pellets with a concentration of 0.026M were the most palatable. The pellet consumption is significantly different if the concentration of citric acid in the pellets differs more than two times. The absolute threshold concentration is 0.01M, or 2.74μg of citric acid per pellet. Sucrose and NaCl have deterrent taste at the highest concentrations tested (0.29 and 1.73M, respectively). Both substances are palatable at 10 times lower concentrations and become indifferent after further gradual decrease in their concentration. CaCl2 decreases the pellets consumption at 0.9M but is an indifferent tastant at lower concentrations (0.45, 0.09 and 0.045M). The number of rejections and repeated grasps of a food pellet is fewness and is not related to the pellet's palatability, while the retention time of pellet in the oral cavity positively and highly correlates with the pellet's palatability. Kutum have opposite taste preferences for most substances tested in comparison with the roach. It indicates that the taste preferences mediated by the oral taste receptors are different in closely related sympatric fish displayed diet divergences.

  19. Kudoa unicapsula n. sp. (Myxosporea: Kudoidae) a parasite of the Mediterranean mullets Liza ramada and L. aurata (Teleostei: Mugilidae).

    PubMed

    Yurakhno, V M; Ovcharenko, M O; Holzer, A S; Sarabeev, V L; Balbuena, J A

    2007-11-01

    A new multivalvulid myxozoan parasite, Kudoa unicapsula n. sp., is described from the intestinal mesentery, intestine and pyloric caeca of the thin-lipped grey mullet Liza ramada (Risso 1826) and the golden grey mullet L. aurata (Risso, 1810) from the Mediterranean coastal waters of Spain. It is characterized by the presence of elongated, rice corn-like white cysts of 0.47-0.56 x 0.18-0.38 mm, filled with tetracapsulate, slightly asymmetric spores, rectangular in apical view and tear-shaped in lateral view with four polar capsules of considerably different size and slightly unequal spore valves with rounded edges, overlapping each other on the apex of the spore. One large polar capsule includes a polar filament coiled in two to three turns, and the other three polar capsules, which are very small, posses only a rudimental filament. Both light and electron microscopy data showed that this species differs from all previously described Kudoa spp. with unequal polar capsules. The molecular analysis based on 18S and 28S ribosomal deoxyribonucleic acid DNA sequence data of K. unicapsula n. sp. indicates a close relationship and thus phylogenetic clustering together with K. trifolia, a myxozoan from the same host and the same geographical location.

  20. Redescription of Liza bandialensis (Teleostei: Mugilidae) with an identification key to mullet species of Eastern Central Atlantic.

    PubMed

    Trape, Sébastien; Harrison, Ian J; Diouf, Papa Samba; Durand, Jean-Dominique

    2012-02-01

    Liza bandialensis Diouf 1991 is redescribed because previous descriptions have not been in well-distributed publications and have lacked sufficient detail or reference to voucher specimens. The description provided here is based on specimens from the Sine Saloum estuary, Senegal (West Africa), from where the species was originally described. The distinctness of the species is confirmed both by meristic and molecular criteria. L. bandialensis presents a unique combination of characters with a low number of scales in the longitudinal series (32-33), 10.5-12 transverse scale rows, and distinctly yellowish dorsal, anal, and caudal fins. The currently known distribution of L. bandialensis includes coastal waters of Senegal, Gambia and Guinea Bissau. Finally, we provide a morphological identification key for the sixteen species of Mugilidae species occurring along the eastern central Atlantic coast of Africa.

  1. Molecular phylogeny of grey mullets (Teleostei: Mugilidae) in Greece: evidence from sequence analysis of mtDNA segments.

    PubMed

    Papasotiropoulos, Vasilis; Klossa-Kilia, Elena; Alahiotis, Stamatis N; Kilias, George

    2007-08-01

    Mitochondrial DNA sequence analysis has been used to explore genetic differentiation and phylogenetic relationships among five species of the Mugilidae family, Mugil cephalus, Chelon labrosus, Liza aurata, Liza ramada, and Liza saliens. DNA was isolated from samples originating from the Messolongi Lagoon in Greece. Three mtDNA segments (12s rRNA, 16s rRNA, and CO I) were PCR amplified and sequenced. Sequencing analysis revealed that the greatest genetic differentiation was observed between M. cephalus and all the other species studied, while C. labrosus and L. aurata were the closest taxa. Dendrograms obtained by the neighbor-joining method and Bayesian inference analysis exhibited the same topology. According to this topology, M. cephalus is the most distinct species and the remaining taxa are clustered together, with C. labrosus and L. aurata forming a single group. The latter result brings into question the monophyletic origin of the genus Liza.

  2. Reproductive biology of Ilisha elongata (Teleostei: Pristigasteridae) in Ariake Sound, Japan: Implications for estuarine fish conservation in Asia

    NASA Astrophysics Data System (ADS)

    Zhang, Jie; Takita, Toru; Zhang, Chunguang

    2009-01-01

    Elongate ilisha ( Ilisha enlongata) is a commercially important species that contributes to clupeoid fisheries in Asian countries. In the present study, the reproductive biology of I. elongata in Ariake Sound, Japan is determined for the first time. Six maturity stages were described using ovarian and testicular histology throughout the annual cycle. The spawning season in Ariake Sound lasts from May to July, with peak spawning activity in May and June. Age at first maturity was estimated to be 2 years, with a few exceptions of 1 year in well-developed males. Ovaries that contained both tertiary yolk oocytes and postovulatory follicles occurred from late May to late July, indicating that I. elongata is a multiple spawner. The size-frequency distribution of oocytes provided evidence for its multiple spawning and accuracy of the fecundity estimates. The batch fecundity of this species was estimated at between 22,200 and 270,900 eggs per individual, increasing with age between two and six years. The present findings on the reproductive strategy of I. elongata in Ariake Sound are generally consistent with those in temperate or subtropical populations, but quite different from those of tropical population where first maturation occurs around 200 days and life spans are shorter, with a maximum age less than 3 years. The conservation implications of this reproductive strategy in a harsh, variable environment in Asian countries are also discussed.

  3. Adaptive radiation in the Congo River: an ecological speciation scenario for African weakly electric fish (Teleostei; Mormyridae; Campylomormyrus).

    PubMed

    Feulner, Philine G D; Kirschbaum, Frank; Tiedemann, Ralph

    2008-01-01

    The ultimate aim of this study is to better understand the diversification of African weakly electric fish in the Congo River. Based on a robust phylogenetic hypothesis we examined the radiation within the mormyrid genus Campylomormyrus. Morphological traits relevant for the divergence between the identified species were detected. Among them, the variation in the shape of the trunk-like elongated snout suggested the presence of different trophic specializations. Furthermore, the chosen model taxon, the genus Campylomormyrus, exhibits a wide diversity of electric organ discharge (EOD) waveforms. A comparison of EOD waveform types and phylogenetic relationships showed major differences in EOD between closely related species. This indicates that the EOD might function as a reproductive isolation mechanism. In conclusion, we provide a plausible scenario of an adaptive radiation triggered by sexual selection and assortative mating based on EOD characteristics, but caused by a divergent selection on the feeding apparatus. These findings point towards an adaptive radiation of at least some Campylomormyrus species occurring in the Lower Congo River.

  4. On Gonorynchus, Gonorhynchus, Gonorinchus, Gonorhinchus and Gonorrhynchus, and some other names of labeonine fishes (Teleostei: Gonorynchidae and Cyprinidae).

    PubMed

    Kottelat, Maurice

    2016-10-25

    The supposed cyprinid genus 'Gonorhynchus McClelland, 1838' does not exist; the name refers to Gonorhynchus Cuvier, 1816, which is a junior objective synonym of Gonorynchus Scopoli, 1777. The correct family-group name, authorship and date are: Gonorynchidae Fowler, 1941 (1848). Tariqilabeo Mirza & Saboohi, 1990 is the valid genus name for the South Asian species earlier placed in Crossocheilus or 'Gonorhynchus'. The family-group names Garrae Bleeker, 1863 and Labeonini Bleeker, 1859 are declared nomina protecta and Platycarinae Macleay, 1841 is declared nomen oblitum.

  5. Evolutionary patterns of shape and functional diversification in the skull and jaw musculature of triggerfishes (Teleostei: Balistidae).

    PubMed

    McCord, Charlene L; Westneat, Mark W

    2016-06-01

    The robust skull and highly subdivided adductor mandibulae muscles of triggerfishes provide an excellent system within which to analyze the evolutionary processes underlying phenotypic diversification. We surveyed the anatomical diversity of balistid jaws using Procrustes-based geometric morphometric analyses and a phylomorphospace approach to quantifying morphological transformation through evolution. We hypothesized that metrics of interspecific cranial shape would reveal patterns of phylogenetic diversification that are congruent with functional and ecological transformation. Morphological landmarks outlining skull and adductor mandibulae muscle shape were collected from 27 triggerfish species. Procrustes-transformed skull shape configurations revealed significant phylogenetic and size-influenced structure. Phylomorphospace plots of cranial shape diversity reveal groupings of shape between different species of triggerfish that are mostly consistent with phylogenetic relatedness. Repeated instances of convergence upon similar cranial shape by genetically disparate taxa are likely due to the functional demands of shared specialized dietary habits. This study shows that the diversification of triggerfish skulls occurs via modifications of cranial silhouette and the positioning of subdivided jaw adductor muscles. Using the morphometric data collected here as input to a biomechanical model of triggerfish jaw function, we find that subdivided jaw adductors, in conjunction with a unique cranial skeleton, have direct biomechanical consequences that are not always congruent with phylomorphospace patterns in the triggerfish lineage. The integration of geometric morphometrics with biomechanical modeling in a phylogenetic context provides novel insight into the evolutionary patterns and ecological role of muscle subdivisions in triggerfishes. J. Morphol. 277:737-752, 2016. © 2016 Wiley Periodicals, Inc.

  6. Varicus lacerta, a new species of goby (Teleostei, Gobiidae, Gobiosomatini, Nes subgroup) from a mesophotic reef in the southern Caribbean

    PubMed Central

    Tornabene, Luke; Robertson, D. Ross; Baldwin, Carole C.

    2016-01-01

    Abstract We describe a new species of goby, Varicus lacerta sp. n., which was collected from a mesophotic reef at Curacao, southern Caribbean. The new species is the tenth species of Varicus, all of which occur below traditional SCUBA depths in the wider Caribbean area. Its placement in the genus Varicus is supported by a molecular phylogenetic analysis of three nuclear genes and the mitochondrial gene cytochrome b. In addition, the new species has one anal-fin pterygiophore inserted anterior to the first haemal spine, which distinguishes Varicus species from most species in the closely related and morphologically similar genus Psilotris. Varicus lacerta sp. n. is distinguished from all other named species of Varicus by the absence of scales, having highly branched, feather-like pelvic-fin rays, and in its live coloration. We provide the cytochrome c oxidase I DNA barcode of the holotype and compare color patterns of all species of Varicus and Psilotris for which color photographs or illustrations are available. This study is one of several recent studies demonstrating the utility of manned submersibles in exploring the diversity of poorly studied but species-rich deep-reef habitats. PMID:27408581

  7. A young clade repeating an old pattern: diversity in Nothonotus darters (Teleostei: Percidae) endemic to the Cumberland River.

    PubMed

    Keck, Benjamin P; Near, Thomas J

    2010-11-01

    Hypotheses of diversification in eastern North American freshwater fishes have focused primarily on allopatric distributions of species between disjunct highland areas and major river systems. However, these hypotheses do not fully explain the rich diversity of species within highland regions and river systems. Relatively old diversification events at small geographic scales have been observed in the Barcheek Darter subclade that occurs in the Cumberland River drainage (CRD) in Kentucky and Tennessee, United States of America, but it is unknown if this pattern is consistent in other darter subclades. We explored phylogeographic diversity in two species of Nothonotus darters, N. microlepidus and N. sanguifluus, endemic to the CRD to compare phylogenetic patterns between Barcheek Darters and species of Nothonotus. We collected sequence data for a mitochondrial gene (cytb) and three nuclear genes (MLL, S7 and RAG1) from 19 N. microlepidus and 35 N. sanguifluus specimens. Gene trees were estimated using maximum likelihood and Bayesian methods, and a 'species tree' was inferred using a Bayesian method. These trees indicate that species diversity in Nothonotus is underestimated. Five distinct lineages were evident, despite retained ancestral polymorphism and unsampled extirpated populations. Comparison of chronograms for Barcheek Darters and Nothonotus revealed that microendemism resulting from species diversification at small geographic scales in the CRD is a consistent pattern in both old and young darter subclades. Our analyses reveal that geographic isolating mechanisms that result in similar phylogeographic patterns in the CRD are persistent through long expanses of evolutionary time.

  8. Free from mitochondrial DNA: Nuclear genes and the inference of species trees among closely related darter lineages (Teleostei: Percidae: Etheostomatinae).

    PubMed

    Near, Thomas J; Keck, Benjamin P

    2013-03-01

    Investigations into the phylogenetics of closely related animal species are dominated by the use of mitochondrial DNA (mtDNA) sequence data. However, the near-ubiquitous use of mtDNA to infer phylogeny among closely related animal lineages is tempered by an increasing number of studies that document high rates of transfer of mtDNA genomes among closely related species through hybridization, leading to substantial discordance between phylogenies inferred from mtDNA and nuclear gene sequences. In addition, the recent development of methods that simultaneously infer a species phylogeny and estimate divergence times, while accounting for incongruence among individual gene trees, has ushered in a new era in the investigation of phylogeny among closely related species. In this study we assess if DNA sequence data sampled from a modest number of nuclear genes can resolve relationships of a species-rich clade of North American freshwater teleost fishes, the darters. We articulate and expand on a recently introduced method to infer a time-calibrated multi-species coalescent phylogeny using the computer program (*)BEAST. Our analyses result in well-resolved and strongly supported time-calibrated darter species tree. Contrary to the expectation that mtDNA will provide greater phylogenetic resolution than nuclear gene data; the darter species tree inferred exclusively from nuclear genes exhibits a higher frequency of strongly supported nodes than the mtDNA time-calibrated gene tree.

  9. Diversification of egg-deposition behaviours and the evolution of male parental care in darters (Teleostei: Percidae: Etheostomatinae).

    PubMed

    Kelly, N B; Near, T J; Alonzo, S H

    2012-05-01

    Male-only care is the most frequent parental care behaviour in teleost fishes, but little is known about its evolutionary origins and patterns of diversity in species-rich lineages. Darters are a clade of North American freshwater fishes that contain both nonparental care species and species with male-only care. In darters, paternal care takes the form of egg-guarding and other egg-tending behaviours that are dependent on the female mode of egg deposition. Male care has been hypothesized to evolve independently in darters at least three times, and it has been thought to be irreversible. We investigated the diversification of egg-deposition behaviours and the evolution of complex male care using published descriptions of darter reproductive behaviours and a multilocus molecular phylogeny that included all 146 species for which reproductive behaviours are known. We find support for two origins of male-only care behaviour. One origin of paternal care occurred relatively early in the radiation of Etheostoma and is characteristic of a recently discovered clade, Goneaperca. The other origin of male-only care occurred much more recently in a derived clade of Nothonotus. Our analyses of character diversification demonstrate reversals from care to noncare and multiple transitions between egg-deposition behaviours that are not associated with parental care.

  10. [Growth and natural mortality of the fish Haemulon aurolineatum (Teleostei: Haemulidae) in the Southwest of Margarita Island, Venezuela].

    PubMed

    Bravo, Edwis; Eslava, Nora; González, Leo

    2009-09-01

    We analyzed the growth and natural mortality of the cují (Haemulon aurolineatum) in the southwest of Margarita Island, from July 2005 through June 2006. A sample of 1,378 males and 1,143 females collected from Boca del Río artisanal fishing vessels was analyzed. The common relation for both sexes was expressed by the equation P=0.038*L(2.87). From the frequency data, a preliminary asymptotic length (L(infinity)) was estimated applying the routine of Powell and Wetherall, and the coefficient of growth (k) through ELEFAN I using program FISAT II (FAO-ICLARM). The modal progression analysis was used, previous decomposition of the frequency of lengths according to Bhattacharya, and it optimized the estimations of L(infinity) and k according to the procedure of Gulland and Holt. The curve of growth in length was fit to the model of von Bertalanffy, and described an exponential curve, where growth accelerated until the two years of age. The rate of natural mortality was high (M = 1.15 year(-1)), probably from high predation.

  11. An evaluation of fossil tip-dating versus node-age calibrations in tetraodontiform fishes (Teleostei: Percomorphaceae).

    PubMed

    Arcila, Dahiana; Alexander Pyron, R; Tyler, James C; Ortí, Guillermo; Betancur-R, Ricardo

    2015-01-01

    Time-calibrated phylogenies based on molecular data provide a framework for comparative studies. Calibration methods to combine fossil information with molecular phylogenies are, however, under active development, often generating disagreement about the best way to incorporate paleontological data into these analyses. This study provides an empirical comparison of the most widely used approach based on node-dating priors for relaxed clocks implemented in the programs BEAST and MrBayes, with two recently proposed improvements: one using a new fossilized birth-death process model for node dating (implemented in the program DPPDiv), and the other using a total-evidence or tip-dating method (implemented in MrBayes and BEAST). These methods are applied herein to tetraodontiform fishes, a diverse group of living and extinct taxa that features one of the most extensive fossil records among teleosts. Previous estimates of time-calibrated phylogenies of tetraodontiforms using node-dating methods reported disparate estimates for their age of origin, ranging from the late Jurassic to the early Paleocene (ca. 150-59Ma). We analyzed a comprehensive dataset with 16 loci and 210 morphological characters, including 131 taxa (95 extant and 36 fossil species) representing all families of fossil and extant tetraodontiforms, under different molecular clock calibration approaches. Results from node-dating methods produced consistently younger ages than the tip-dating approaches. The older ages inferred by tip dating imply an unlikely early-late Jurassic (ca. 185-119Ma) origin for this order and the existence of extended ghost lineages in their fossil record. Node-based methods, by contrast, produce time estimates that are more consistent with the stratigraphic record, suggesting a late Cretaceous (ca. 86-96Ma) origin. We show that the precision of clade age estimates using tip dating increases with the number of fossils analyzed and with the proximity of fossil taxa to the node under assessment. This study suggests that current implementations of tip dating may overestimate ages of divergence in calibrated phylogenies. It also provides a comprehensive phylogenetic framework for tetraodontiform systematics and future comparative studies.

  12. †Kenyaichthyidae fam. nov. and †Kenyaichthys gen. nov. - First Record of a Fossil Aplocheiloid Killifish (Teleostei, Cyprinodontiformes).

    PubMed

    Altner, Melanie; Reichenbacher, Bettina

    2015-01-01

    The extant Cyprinodontiformes (killifishes) with their two suborders Cyprinodontoidei and Aplocheiloidei represent a diverse and well-studied group of fishes. However, their fossil record is comparatively sparse and has so far yielded members of the Cyprinodontoidei only. Here we report on cyprinodontiform fossils from the upper Miocene Lukeino Formation in the Tugen Hills of the Central Rift Valley of Kenya, which represent the first fossil record of an aplocheiloid killifish. A total of 169 specimens - mostly extraordinarily well preserved - and a sample of ten extant cyprinodontiform species were studied on the basis of morphometrics, meristics and osteology. A phylogenetic analysis using PAUP was also conducted for the fossils. Both the osteological data and the phylogenetic analysis provide strong evidence for the assignment of the fossils to the Aplocheiloidei, and justify the definition of the new family †Kenyaichthyidae, the new genus †Kenyaichthys and the new species †K. kipkechi sp. nov. The phylogenetic analysis unexpectedly places †Kenyaichthys gen. nov. in a sister relationship to the Rivulidae (a purely Neotropical group), a probable explanation might be lack of available synapomorphies for the Rivulidae, Nothobranchiidae and Aplocheilidae. The specimens of †K. kipkechi sp. nov. show several polymorphic characters and large overlap in meristic traits, which justifies their interpretation as a species flock in statu nascendi. Patterns of variation in neural and haemal spine dimensions in the caudal vertebrae of †Kenyaichthys gen. nov. and the extant species studied indicate that some previously suggested synapomorphies of the Cyprinodontoidei and Aplocheiloidei need to be revised.

  13. DNA barcoding at riverscape scales: assessing biodiversity among fishes of the genus Cottus (Teleostei) in northern Rocky Mountain streams.

    PubMed

    Young, Michael K; McKelvey, Kevin S; Pilgrim, Kristine L; Schwartz, Michael K

    2013-07-01

    There is growing interest in broad-scale biodiversity assessments that can serve as benchmarks for identifying ecological change. Genetic tools have been used for such assessments for decades, but spatial sampling considerations have largely been ignored. Here, we demonstrate how intensive sampling efforts across a large geographical scale can influence identification of taxonomic units. We used sequences of mtDNA cytochrome c oxidase subunit 1 and cytochrome b, analysed with maximum parsimony networks, maximum-likelihood trees and genetic distance thresholds, as indicators of biodiversity and species identity among the taxonomically challenging fishes of the genus Cottus in the northern Rocky Mountains, USA. Analyses of concatenated sequences from fish collected in all major watersheds of this area revealed eight groups with species-level differences that were also geographically circumscribed. Only two of these groups, however, were assigned to recognized species, and these two assignments resulted in intraspecific genetic variation (>2.0%) regarded as atypical for individual species. An incomplete inventory of individuals from throughout the geographical ranges of many species represented in public databases, as well as sample misidentification and a poorly developed taxonomy, may have hampered species assignment and discovery. We suspect that genetic assessments based on spatially robust sampling designs will reveal previously unrecognized biodiversity in many other taxa.

  14. Phylogenetic relationships within the speciose family Characidae (Teleostei: Ostariophysi: Characiformes) based on multilocus analysis and extensive ingroup sampling

    PubMed Central

    2011-01-01

    Background With nearly 1,100 species, the fish family Characidae represents more than half of the species of Characiformes, and is a key component of Neotropical freshwater ecosystems. The composition, phylogeny, and classification of Characidae is currently uncertain, despite significant efforts based on analysis of morphological and molecular data. No consensus about the monophyly of this group or its position within the order Characiformes has been reached, challenged by the fact that many key studies to date have non-overlapping taxonomic representation and focus only on subsets of this diversity. Results In the present study we propose a new definition of the family Characidae and a hypothesis of relationships for the Characiformes based on phylogenetic analysis of DNA sequences of two mitochondrial and three nuclear genes (4,680 base pairs). The sequences were obtained from 211 samples representing 166 genera distributed among all 18 recognized families in the order Characiformes, all 14 recognized subfamilies in the Characidae, plus 56 of the genera so far considered incertae sedis in the Characidae. The phylogeny obtained is robust, with most lineages significantly supported by posterior probabilities in Bayesian analysis, and high bootstrap values from maximum likelihood and parsimony analyses. Conclusion A monophyletic assemblage strongly supported in all our phylogenetic analysis is herein defined as the Characidae and includes the characiform species lacking a supraorbital bone and with a derived position of the emergence of the hyoid artery from the anterior ceratohyal. To recognize this and several other monophyletic groups within characiforms we propose changes in the limits of several families to facilitate future studies in the Characiformes and particularly the Characidae. This work presents a new phylogenetic framework for a speciose and morphologically diverse group of freshwater fishes of significant ecological and evolutionary importance across the Neotropics and portions of Africa. PMID:21943181

  15. Host and environmental risk factors associated with Cryptosporidium scophthalmi (Apicomplexa) infection in cultured turbot, Psetta maxima (L.) (Pisces, Teleostei).

    PubMed

    Alvarez-Pellitero, Pilar; Perez, Andrés; Quiroga, M Isabel; Redondo, M José; Vázquez, Sonia; Riaza, Ana; Palenzuela, Oswaldo; Sitjà-Bobadilla, Ariadna; Nieto, José M

    2009-11-12

    An epidemiological cohort study of Cryptosporidium scophthalmi in cultured turbot Psetta maxima L. of Northwestern Spain was conducted along a four-year period. Four different ongrowing cohorts were monitored monthly from introduction into the ongrowing tanks (10-50 g) until reaching market size (400-1400 g). The association of host and environmental factors with five categories of parasite abundance was assessed using a multivariable regression framework. Epidemiological factors assessed here were water temperature, weight, length, month of collection, season, age, origin, condition factor, water filtration, and status to the myxozoan Enteromyxum scophthalmi infection. E. scophthalmi was included into the analysis because it targets the same organ than C. scophthalmi and it was prevalent in the studied population. The multivariable analysis demonstrated the statistically significant association between several factors and parasite abundance. C. scophthalmi abundance was associated (P<0.05) with age, condition factor, season, and status to E. scophthalmi infection. Young animals, with poor condition factor, during spring or summer, and not infected with the myxozoan were most likely to be highly infected by C. scophthalmi. Inclusion of these four variables significantly (P<0.05) improved the model, compared to the model that did not include any of these epidemiological factors. Increasing levels of C. scophthalmi abundance were associated (P<0.01) with higher severity of C. scophthalmi-compatible lesions. The frequency of distribution of C. scophthalmi abundance was clearly right-skewed and fitted a negative binomial distribution, whereas the intensity of infection fitted a Poisson distribution. The quantification of the variance-to-mean ratio stratified by age demonstrated overdispersion for 8-16 months old fish, although this bivariate association is likely affected by several other factors, as suggested by the results of the multivariable analysis. The negative relation between C. scophthalmi abundance and status to E. scophthalmi infection suggests differences in the transmission, onset, and course of both infections. The coarse filtration used in some cohorts did not significantly affect the levels of infection. C. scophthalmi was probably introduced into the ongrowing tanks mainly with carrier fish, though the involvement of infective oocysts from the water supply cannot be disregarded. Infection prevalence and mean intensity decreased with fish age and a seasonal distribution was found. Results presented here will help to understand the epidemiology of C. scophthalmi in turbot, to estimate the expected levels of infection associated with presence or absence of epidemiological factors, and to quantify the impact that the disease may have on susceptible turbot populations. The multivariable model used here is more powerful than the visual inspection of graphics for exploring associations in cooperative processes and can be easily extended to the assessment of epidemiological associations in other population and parasitic diseases.

  16. Glyptothorax mibangi, a new species of catfish (Teleostei: Sisoridae) from the Tisa River, Arunachal Pradesh, northeast India.

    PubMed

    Darshan, Achom; Dutta, Rashmi; Kachari, Akash; Gogoi, Budhin; Das, Debangshu Narayan

    2015-05-22

    Glyptothorax mibangi, a new sisorid catfish, is described from the Tisa River of Arunachal Pradesh, India. The new species can be distinguished from its congeners in the Ganga-Brahmaputra and Barak-Surma-Meghna basins by the following combination of characters: an obtuse leaf-shaped thoracic adhesive apparatus with a spindle-shaped median depression, skin ridges present over the entire apparatus including the depressed region; ventral surface of pectoral spine and first pelvic-fin ray non-plaited; slender body with depth of 10.4-13.5% SL; caudal peduncle shallow with depth 6.8-8.3% SL; snout long with length 52.9-58.6% HL; and 2+7 gill rakers on the first branchial arch.

  17. The SSRI fluoxetine exhibits mild effects on the reproductive axis in the cichlid fish Cichlasoma dimerus (Teleostei, Cichliformes).

    PubMed

    Dorelle, Luciana S; Da Cuña, Rodrigo H; Rey Vázquez, Graciela; Höcht, Christian; Shimizu, Akio; Genovese, Griselda; Lo Nostro, Fabiana L

    2017-03-01

    Among the wide variety of pharmaceuticals released into the environment, Fluoxetine (FLX), a selective serotonin reuptake inhibitor, is one of the most prescribed for the treatment of major depression. It inhibits serotonin (5-HT) reuptake at the presinaptic membrane, increasing serotonergic activity. In vertebrates, including fish, the serotonergic system is closely related to the Hypothalamic Pituitary Gonadal (HPG) axis which regulates reproduction. As FLX can act as an endocrine disrupting compound (EDC) by affecting several reproductive parameters in fish, the aim of this study was to provide an integral assessment of the potential effect of FLX on the reproductive axis of the Neotropical freshwater fish Cichlasoma dimerus. Adult fish were intraperitoneally injected with 2 μg g(-1) FLX or saline every third day for 15 days. No significant differences were found on serotonergic turnover (5-HIAA/5-HT ratio). Pituitary βLH content in FLX injected females was significantly higher than control females; no significant differences were seen for βFSH content. Sex steroids remained unaltered, both in males and females fish, after FLX treatment. No plasma vitellogenin was induced in treated males. Some alterations were seen in testes of FLX injected males, such as the presence of foam cells and an acidophilic PAS positive, Alcian-Blue negative secretion in the lobular lumen. Although there is no clear consensus about the effect of this drug on reproductive physiology, these results indicate that FLX is acting as a mild EDC in adults of C. dimerus.

  18. Gene rearrangements and evolution of tRNA pseudogenes in the mitochondrial genome of the parrotfish (Teleostei: Perciformes: Scaridae).

    PubMed

    Mabuchi, Kohji; Miya, Masaki; Satoh, Takashi P; Westneat, Mark W; Nishida, Mutsumi

    2004-09-01

    Genomic size of animal mitochondrial DNA is usually minimized over time. Thus, when regional duplications occur, they are followed by a rapid elimination of redundant material. In contrast to this general view, we report here long-sustained tRNA pseudogenes in the mitochondrial genome (mitogenome) of teleost fishes of the family Scaridae (parrotfishes). During the course of a molecular phylogenetic study of the suborder Labroidei, we determined the complete nucleotide sequence of the mitogenome for a parrotfish, Chlorurus sordidus, and found a gene rearrangement accompanied by a tRNA pseudogene. In the typical gene order of vertebrates, a tRNA-gene cluster between ND1 and ND2 genes includes tRNA(Ile) (I), tRNA(Gln) (Q), and tRNA(Met) (M) genes in this order (IQM). However, in the mitogenome of the parrotfish, the tRNA(Met) gene was inserted between the tRNA(Ile) and the tRNA(Gln) genes, and the tRNA(Gln) gene was followed by a putative tRNA(Met) pseudogene (psiM). Such a tRNA gene rearrangement including a pseudogene (IMQpsiM) was found in all of the 10 examined species, representing 7 of the 10 currently recognized scarid genera. All sister groups examined (20 species of Labridae and a single species of Odacidae) had the typical gene order of vertebrate mitogenomes. Phylogenetic analysis of the tRNA(Met) genes and the resulting pseudogenes demonstrated that the ancestral tRNA(Met) gene was duplicated in a common ancestor of the parrotfish. Based on the fossil record, these results indicate that the pseudogenes have survived at least 14 million years. Most of the vertebrate mitochondrial gene rearrangements involving the IQM region have held the tRNA(Met) gene just upstream of the ND2 gene, and even in a few exceptional cases, including the present ones, the tRNA pseudogenes have been found in that position. In addition, most of these tRNA(Met) pseudogenes maintained clover-leaf secondary structures, with the remainder sustaining the clover-leaf structure in the "top half (TpsiC and acceptor arms). Considering their potential secondary structures (holding "top halves" of the clover-leaf structures), locations within mitogenomes (flanking the 5' ends of the ND2 genes) and stabilities over time (survived at least 14 Myr), it is likely that the tRNA pseudogenes retain function as punctuation marks for mitochondrial ND2 mRNA processing.

  19. Phylogenetic relationships of the Cobitoidea (Teleostei: Cypriniformes) inferred from mitochondrial and nuclear genes with analyses of gene evolution.

    PubMed

    Liu, Si-Qing; Mayden, Richard L; Zhang, Jia-Bo; Yu, Dan; Tang, Qiong-Ying; Deng, Xin; Liu, Huan-Zhang

    2012-10-15

    The superfamily Cobitoidea of the order Cypriniformes is a diverse group of fishes, inhabiting freshwater ecosystems across Eurasia and North Africa. The phylogenetic relationships of this well-corroborated natural group and diverse clade are critical to not only informing scientific communities of the phylogeny of the order Cypriniformes, the world's largest freshwater fish order, but are key to every area of comparative biology examining the evolution of traits, functional structures, and breeding behaviors to their biogeographic histories, speciation, anagenetic divergence, and divergence time estimates. In the present study, two mitochondrial gene sequences (COI, ND4+5) and four single-copy nuclear gene segments (RH1, RAG1, EGR2B, IRBP) were used to infer the phylogenetic relationships of the Cobitoidea as reconstructed from maximum likelihood (ML) and partitioned Bayesian Analysis (BA). Analyses of the combined mitochondrial/nuclear gene datasets revealed five strongly supported monophyletic Cobitoidea families and their sister-group relationships: Botiidae+(Vaillantellidae+(Cobitidae+(Nemacheilidae+Balitoridae))). These recovered relationships are in agreement with previous systematic studies on the order Cypriniformes and/or those focusing on the superfamily Cobitoidea. Using these relationships, our analyses revealed pattern lineage- or ecological-group-specific evolution of these genes for the Cobitoidea. These observations and results corroborate the hypothesis that these group-specific-ancestral ecological characters have contributed in the diversification and/or adaptations within these groups. Positive selections were detected in RH1 of nemacheilids and in RAG1 of nemacheilids and genus Vaillantella, which indicated that evolution of RH1 (related to eye's optic sense) and RAG1 (related to immunity) genes appeared to be important for the diversification of these groups. The balitorid lineage (those species inhabiting fast-flowing riverine habitats) had, as compared with other cobitoid lineages, significantly different dN/dS, dN and dS values for ND4 and IRBP genes. These significant differences are usually indicative of weaker selection pressure, and lineage-specific evolution on genes along the balitorid lineage. Furthermore, within Cobitoidea, excluding balitorids, species living in subtropics had significantly higher dN/dS values in RAG1 and IRBP genes than those living in temperate and tropical zones. Among tropical cobitoids, genes COI, ND5, EGR2B, IRBP and RH1, had a significantly higher mean dS value than those species in subtropical and temperate groups. These findings suggest that the evolution of these genes could also be ecological-group-specific and may have played an important role in the adaptive evolution and diversification of these groups. Thus, we hypothesize that the genes included in the present study were actively involved in lineage- and/or ecological-group-specific evolutionary processes of the highly diverse Cobitoidea. These two evolutionary patterns, both subject to further testing, are hypothesized as integral in the diversification with this major clade of the world's most diverse group of freshwater fishes.

  20. Concerted Evolution of Duplicate Control Regions in the Mitochondria of Species of the Flatfish Family Bothidae (Teleostei: Pleuronectiformes).

    PubMed

    Li, Dong-He; Shi, Wei; Munroe, Thomas A; Gong, Li; Kong, Xiao-Yu

    2015-01-01

    Mitogenomes of flatfishes (Pleuronectiformes) exhibit the greatest diversity of gene rear-rangements in teleostean fishes. Duplicate control regions (CRs) have been found in the mito-genomes of two flatfishes, Samariscus latus (Samaridae) and Laeops lanceolata (Bothidae), which is rare in teleosts. It has been reported that duplicate CRs have evolved in a concerted fashion in fishes and other animals, however, whether concerted evo-lution exists in flatfishes remains unknown. In this study, based on five newly sequenced and six previously reported mitogenomes of lefteye flounders in the Bothidae, we explored whether duplicate CRs and concerted evolution exist in these species. Results based on the present study and previous reports show that four out of eleven bothid species examined have duplicate CRs of their mitogenomes. The core regions of the duplicate CRs of mitogenomes in the same species have identical, or nearly identical, sequences when compared to each other. This pattern fits the typical characteristics of concerted evolution. Additionally, phylogenetic and ancestral state reconstruction analysis also provided evidence to support the hypothesis that duplicate CRs evolved concertedly. The core region of concerted evolution is situated at the conserved domains of the CR of the mitogenome from the termination associated sequences (TASs) to the conserved sequence blocks (CSBs). Commonly, this region is con-sidered to regulate mitochondrial replication and transcription. Thus, we hypothesize that the cause of concerted evolution of the duplicate CRs in the mtDNAs of these four bothids may be related to some function of the conserved sequences of the CRs during mitochondrial rep-lication and transcription. We hope our results will provide fresh insight into the molecular mechanisms related to replication and evolution of mitogenomes.

  1. Comparative cytogenetics of ten species of cichlid fishes (Teleostei, Cichlidae) from the Araguaia River system, Brazil, by conventional cytogenetic methods.

    PubMed

    Valente, G Targino; Vitorino, C de Andrade; Cabral-de-Mello, D C; Oliveira, C; Souza, I Lima; Martins, C; Venere, P C

    2012-01-01

    Cichlids represent one of the most species-rich families of fishes and have attracted the attention of evolutionary biologists due to the rapid radiation occurring in some groups and the importance of some species in the world aquaculture. Cytogenetic analysis was conducted in 10 cichlid species from the Araguaia River, Amazon Basin, Brazil. The chromosome number was 2n=48 for all analyzed species except for Laetacara araguaiae Ottoni et Costa, 2009 (2n=44). Chromosomal polymorphism was detected only in Geophagus proximus (Castelnau, 1855), which exhibits an extra large submetacentric and and a dot-like chromosomes. Moreover, the C-banding revealed a general pericentromeric heterochromatic pattern and some additional blocks for some species. The heterochromatic blocks corresponding to AgNOR bearing regions were observed in all species and also corresponded to CMA3 positive blocks, which were observed in terminal regions. Besides the general conserved chromosomal and heterochromatin patterns for South American cichlids, the presence of GC-rich heterochromatin was quite different in the species Biotodoma cupido (Heckel, 1840), Geophagus proximus, Retroculus lapidifer (Castelnau, 1855), Crenicichla strigata Günther, 1862 and Heros efasciatus Heckel, 1840. The results suggest that independent events of heterochromatin modification occurred during chromosome evolution in the group, regardless of the conservation of macro-chromosomal structure.

  2. Further evidence for the invasion and establishment of Pterois volitans (Teleostei: Scorpaenidae) along the Atlantic Coast of the United States

    USGS Publications Warehouse

    Meister, H.S.; Wyanski, D.M.; Loefer, J.K.; Ross, S.W.; Quattrini, A.M.; Sulak, K.J.

    2005-01-01

    We document the continued population expansion of red lionfish, Pterois volitans, the first documented successful introduction of an invasive marine fish species from the western Pacific to Atlantic coastal waters of the United States. Red lionfish are indigenous to the Indo-Pacific and have apparently established one or more breeding populations on reefs off the southeastern United States. Fifty-nine specimens, most presumably adult red lionfish, were documented or collected on live-bottom reefs off North Carolina, South Carolina, and Florida, and on a manmade structure off Georgia. Observation/collection depths and bottom water temperatures for these fish ranged from 40-99 m and 13.8-24.4??C, respectively. Eleven juvenile lionfish, believed to be expatriated from southeastern waters, were collected in estuaries along the coast of Long Island, NY, at depths of 0-5 m and water temperatures ranging from 13.8-16.5??C. Twelve of the total 70 specimens collected or observed were positively identified as red lionfish. Based on histological assessment of gonad tissue, two reproductively-active males and one immature female were collected. The life history of red lionfish, especially their reproductive biology and food habits, should be investigated along the east coast of the US to determine the potential impacts of this species on ecosystems they have invaded.

  3. Before the freeze: otoliths from the Eocene of Seymour Island, Antarctica, reveal dominance of gadiform fishes (Teleostei).

    PubMed

    Schwarzhans, Werner; Mörs, Thomas; Engelbrecht, Andrea; Reguero, Marcelo; Kriwet, Jürgen

    2017-01-01

    The first record of fossil teleostean otoliths from Antarctica is reported. The fossils were obtained from late Early Eocene shell beds of the La Meseta Formation, Seymour Island that represent the last temperate marine climate phase in Antarctica prior to the onset of cooling and subsequent glaciation during the late Eocene. A total of 17 otolith-based teleost taxa are recognized, with 10 being identifiable to species level containing nine new species and one new genus: Argentina antarctica sp. nov., Diaphus? marambionis sp. nov., Macruronus eastmani sp. nov., Coelorinchus balushkini sp. nov., Coelorinchus nordenskjoeldi sp. nov., Palimphemus seymourensis sp. nov., Hoplobrotula? antipoda sp. nov., Notoberyx cionei gen. et sp. nov. and Cepola anderssoni sp. nov. Macruronus eastmani sp. nov. is also known from the late Eocene of Southern Australia, and Tripterophycis immutatus Schwarzhans, widespread in the southern oceans during the Eocene, has been recorded from New Zealand, southern Australia, and now Antarctica. The otolith assemblage shows a typical composition of temperate fishes dominated by gadiforms, very similar at genus and family levels to associations known from middle Eocene strata of New Zealand and the late Eocene of southern Australia, but also to the temperate Northern Hemisphere associations from the Paleocene of Denmark. The Seymour Island fauna bridges a gap in the record of global temperate marine teleost faunas during the early Eocene climate maximum. The dominant gadiforms are interpreted as the main temperate faunal component, as in the Paleocene of Denmark. Here they are represented by the families Moridae, Merlucciidae (Macruroninae), Macrouridae and Gadidae. Nowadays Gadidae are a chiefly Northern Hemisphere temperate family. Moridae, Macruroninae and Macrouridae live today on the lower shelf to deep-water or mesopelagically with Macruroninae being restricted to the Southern Ocean. The extant endemic Antarctic gadiform family Muraenolepididae is missing, as are the dominant modern Antarctic fishes of the perciform suborder Notothenioidei. Recently, there has been much debate on isolated jaw bones of teleost fishes found in the La Meseta Formation and whether they would represent gadiforms (Merlucciidae in this case) or some early, primitive notothenioid. Otoliths are known to often complement rather than duplicate skeletal finds. With this in mind, we conclude that our otolith data support the presence of gadiforms in the early Eocene of Antarctica while it does not rule out the presence of notothenioids at the same time. http://zoobank.org/urn:lsid:zoobank.org:pub:A30E5364-0003-4467-B902-43A41AD456CC.

  4. Integrative taxonomy of Anisakidae and Raphidascarididae (Nematoda) in Paralichthys patagonicus and Xystreurys rasile (Pisces: Teleostei) from Brazil.

    PubMed

    Fonseca, Michelle Cristie Gonçalves da; Knoff, Marcelo; Felizardo, Nilza Nunes; Di Azevedo, Maria Isabel N; Torres, Eduardo José Lopes; Gomes, Delir Corrêa; Iñiguez, Alena Mayo; São Clemente, Sérgio Carmona de

    2016-10-17

    Thirty-six Paralichthys patagonicus and 30 Xystreurys rasile were collected in the state of Rio de Janeiro, Brazil to investigate the presence of anisakid and raphidascaridid nematodes. Anisakis typica, Terranova sp., Contracaecum sp., Hysterothylacium deardorffoverstreetorum, and Raphidascaris sp. were identified using integrative taxonomy of morphological and genetic data. Morphological and morphometric analysis was conducted using bright field microscopy with scanning electron microscopy for topographic characterization of the cuticular surface. Phylogenetic analysis, using ITS and cox2 molecular targets, clearly demonstrated the species identification of A. typica and H. deardorffoverstreetorum and the high diversity of H. deardorffoverstreetorum. This is the first report of A. typica, H. deardorffoverstreetorum, and Raphidascaris sp. parasitizing P. patagonicus and X. rasile.

  5. Wrapped in flames: Corydoras hephaestus, a new remarkably colored species from the Rio Madeira basin (Teleostei: Callichthyidae).

    PubMed

    Ohara, Willian Massaharu; Tencatt, Luiz F C; Britto, Marcelo R

    2016-09-26

    A new species of Corydoras is described from the upper Rio Machado, Rio Madeira basin, Rondônia State, Brazil. The new species can be distinguished from its congeners by the absence of contact between the posterior process of the parieto-supraoccipital and the nuchal plate; a ventral laminar expansion of the infraorbital 1 conspicuously developed; and the posterior margin of the pectoral-fin spine with serrations along almost of its entire length, only lacking in the distal portion. Additionally, Corydoras hephaestus possesses dorsal and pectoral spines short, and exhibits an unusual color pattern in life. The conservation status of the new species and other endemic species are briefly commented.

  6. Haemopoiesis in the head kidney of tilapia, Oreochromis niloticus (Teleostei: Cichlidae): a morphological (optical and ultrastructural) study

    PubMed Central

    Abdel-Aziz, El-Saydah H.; Abdu, Suzan B. S.; Fouad, Huda F.

    2009-01-01

    The present work focused on the histological and ultrastructural studies on haemopoiesis in the kidney of tilapia, Oreochromis niloticus. Haemopoietic tissue was found mainly in the head kidney and a small amount occurred in the mesonephros. The haemopoiesis of tilapia had the following series: erythropoiesis, granulopoiesis, thrombopoiesis, monopoiesis and lymphoplasmopoiesis. Erythropoiesis includes proerythroblasts, basophilic erythroblasts, polychromatic erythroblasts, acidophilic erythroblasts and young and mature erythrocytes. The proerythroblasts were the largest cells in the erythropoietic series. During the maturation process both the nuclear and cellular size decreased gradually due to the chromatin condensation and the progressive substitution of cytoplasmic matrix with a large amount of haemoglobin. Granulopoietic series consisted of cells with variable shape and size at different stages of maturity from myeloblasts to mature granulocytes. The promyelocytes were the largest cells in the series and were characterised by the appearance of primary (azoruphilic) granules. The maturation process involved the appearance of specific granules in the heterophilic, eosinophilic and basophilic series. It is important to mention that eosinophilic granulocytes were the dominant granulopoietic series in the haemopoietic tissue (Ht) of tilapia. Lymphopoietic series consisted of lymphoblasts, large lymphocytes, small lymphocytes and active and inactive plasma cells. Thrombopoietic series consisted of thromboblasts, prothromboblasts and thrombocytes. Thrombocytes of tilapia were nucleated and possessed a spindle shape. Melanomacrophage centres were dominant among the Ht of the head kidney. Also, monocytes were detected and shown to be large cells with an indented nucleus and cytoplasm containing numerous vesicles of different sizes and a few lysosomes. PMID:19152117

  7. Understanding morphological variability in a taxonomic context in Chilean diplomystids (Teleostei: Siluriformes), including the description of a new species

    PubMed Central

    2017-01-01

    Following study of the external morphology and its unmatched variability throughout ontogeny and a re-examination of selected morphological characters based on many specimens of diplomystids from Central and South Chile, we revised and emended previous specific diagnoses and consider Diplomystes chilensis, D. nahuelbutaensis, D. camposensis, and Olivaichthys viedmensis (Baker River) to be valid species. Another group, previously identified as Diplomystes sp., D. spec., D. aff. chilensis, and D. cf. chilensis inhabiting rivers between Rapel and Itata Basins is given a new specific name (Diplomystes incognitus) and is diagnosed. An identification key to the Chilean species, including the new species, is presented. All specific diagnoses are based on external morphological characters, such as aspects of the skin, neuromast lines, and main lateral line, and position of the anus and urogenital pore, as well as certain osteological characters to facilitate the identification of these species that previously was based on many internal characters. Diplomystids below 150 mm standard length (SL) share a similar external morphology and body proportions that make identification difficult; however, specimens over 150 mm SL can be diagnosed by the position of the urogenital pore and anus, and a combination of external and internal morphological characters. According to current knowledge, diplomystid species have an allopatric distribution with each species apparently endemic to particular basins in continental Chile and one species (O. viedmensis) known only from one river in the Chilean Patagonia, but distributed extensively in southern Argentina. PMID:28224053

  8. The eels of the genus Nettenchelys, with description of a new species from Taiwan (Teleostei: Anguilliformes: Nettastomatidae).

    PubMed

    Smith, David G; Lin, James; Chen, Hong-Ming; Pogonoski, John J

    2015-12-24

    The species of the genus Nettenchelys are summarized. Nine species are recognized on the basis of adult specimens: Nettenchelys dionisi Brito, N. erroriensis Karmovskaya, N. exoria Böhlke & Smith, N. gephyra Castle & Smith, N. inion Smith & Böhlke, N. paxtoni Karmovskaya, N. proxima new species, N. pygmaea Smith & Böhlke, and N. taylori Alcock. Another species, N. bellottii (D'Ancona) is based on a larva. Nettenchelys gephyra is redescribed on the basis of additional specimens from northeastern Taiwan, Indonesia and Australia. Nettenchelys proxima new species is described from a specimen from southwestern Taiwan. Nettenchelys sp. reported by Uyeno & Sasaki (1983) is found to be a specimen of Facciolella. Information on larvae is updated based on new knowledge of the genus.

  9. Molecular and cytogenetic analysis of the telomeric (TTAGGG)n repetitive sequences in the Nile tilapia, Oreochromis niloticus (Teleostei: Cichlidae).

    PubMed

    Chew, Joyce S K; Oliveira, Claudio; Wright, Jonathan M; Dobson, Melanie J

    2002-03-01

    The majority of chromosomes in Oreochromis niloticus, as with most fish karyotyped to date, cannot be individually identified owing to their small size. As a first step in establishing a physical map for this important aquaculture species of tilapia we have analyzed the location of the vertebrate telomeric repeat sequence, (TTAGGG)n, in O. niloticus. Southern blot hybridization analysis and a Bal31 sensitivity assay confirm that the vertebrate telomeric repeat is indeed present at O. niloticus chromosomal ends with repeat tracts extending for 4-10 kb on chromosomal ends in erythrocytes. Fluorescent in situ hybridization revealed that (TTAGGG)n is found not only at telomeres, but also at two interstitial loci on chromosome 1. These data support the hypothesis that chromosome 1, which is significantly larger than all the other chromosomes in the karyotype, was produced by the fusion of three chromosomes and explain the overall reduction of chromosomal number from the ancestral teleost karyotype of 2n=48 to 2n=44 observed in tilapia.

  10. Pseudorhabdosynochus regius n. sp. (Monogenea, Diplectanidae) from the mottled grouper Mycteroperca rubra (Teleostei) in the Mediterranean Sea and Eastern Atlantic

    PubMed Central

    Chaabane, Amira; Neifar, Lassad; Justine, Jean-Lou

    2015-01-01

    Pseudorhabdosynochus regius n. sp. is described from the gills of the mottled grouper Mycteroperca rubra caught off Senegal, Tunisia and Libya (type-locality: off Dakar, Senegal). The species is distinguished from its congeners by the structure of its sclerotised vagina (length 26–35 μm), which exhibits a trumpet in continuity with the primary canal, a straight primary canal, and primary and secondary chambers included in a common sclerotised mass along the primary canal. The species is also characterised by small squamodiscs (length 20–40 μm) with 10–11 rows of rodlets. Its closest relatives (based on the structure of the sclerotised vagina) are species mostly found in the Mediterranean Sea and parasites on species of Mycteroperca. A second species of Pseudorhabdosynochus Yamaguti, 1958 is reported from the same host and localities but not described. A list of diplectanids from groupers in the Mediterranean Sea is provided. We point out that a recent article was not compliant with the new Article 8.5.3 of the International Code of Zoological Nomenclature; for this reason, three species, P. nhatrangensis Dang, Bristow, Schander & Berland, 2013, P. vietnamensis Dang et al., 2013 and P. brunei Dang et al., 2013, are invalid. PMID:25674913

  11. Molecular Identification and Traceability of Illegal Trading in Lignobrycon myersi (Teleostei: Characiformes), a Threatened Brazilian Fish Species, Using DNA Barcode

    PubMed Central

    Rodrigues, Alexandre dos Santos; Brandão, José Henrique Souza Galdino; Bitencourt, Jamille de Araújo; Jucá-Chagas, Ricardo; Sampaio, Iracilda; Schneider, Horácio

    2016-01-01

    Lignobrycon myersi is a threatened freshwater fish species and endemic of a few coastal rivers in northeastern Brazil. Even though the Brazilian laws prohibit the fisheries of threatened species, L. myersi is occasionally found in street markets, being highly appreciated by local population. In order to provide a reliable DNA barcode dataset for L. myersi, we compared mitochondrial sequences of cytochrome c oxidase subunit I (COI) from fresh, frozen, and salt-preserved specimens. Phylogenetically related species (Triportheus spp.) and other fish species (Astyanax fasciatus) commonly mixed with L. myersi in street markets were also included to test the efficiency of molecular identification. In spite of the differences in conservation processes and advanced deterioration of some commercial samples, high-quality COI sequences were obtained and effective in discriminating L. myersi specimens. In addition, while populations from Contas and Almada River basins seem to comprise a single evolutionary lineage, the specimens from Cachoeira River were genetically differentiated, indicating population structuring. Therefore, DNA barcoding has proved to be useful to trace the illegal trading of L. myersi and to manage threatened populations, which should focus on conservation of distinct genetic stocks and mitigation on human impacts along their range. PMID:27668281

  12. Auerbachia bajadi sp. n. (Myxozoa: Auerbachiidae) infecting the gallbladder of orangespotted trevally Carangoides bajad (Teleostei: Carangidae) in the Red Sea.

    PubMed

    Abdel-Baki, Abdel-Azeem Sh

    2010-08-01

    Light microscopic description was presented for a new myxosporean species, Auerbachia bajadi. The parasite was collected from the gallbladder of orangespotted trevally Carangoides bajad (Forsskål, 1775) in Al-Quseir city, Red Sea coast, Egypt. The prevalence was 30/80 (37%) and the infection was reported as an enormous amount of free mature spores floating in the bile. Spores were club-shaped with a broad anterior part and a narrow caudal part. Shell valves were asymmetrical and the larger valve was drawn into a wide caudal projection. The mean spore measurements were 22.7 mum in total length and 9.5 mum in width. Polar capsule was single and elliptical-shaped with five polar filament turns. The polar capsule measured 9.5 mum in length and 4.5 mum in width. The spores were distinctly different from the four recorded species of genus Auerbachia. One of the cited species of this genus was excluded as it was related to genus Coccomyxa than genus Auerbachia. Also, the accurate citation date of this genus was discussed.

  13. Ultrastructural study of vitellogenesis and oogenesis of Crepidostomum metoecus (Digenea, Allocreadiidae), intestinal parasite of Salmo trutta (Pisces, Teleostei)

    PubMed Central

    Greani, Samuel; Quilichini, Yann; Marchand, Bernard

    2016-01-01

    We describe the vitellogenesis and oogenesis of Crepidostomum metoecus from Salmo trutta collected in Corsica. This is the first study conducted in the Allocreadiidae family. The maturation of C. metoecus vitellocytes comprises four different stages depending on organelle content. The follicular vitellarium is surrounded by a basal lamina. Vitellocytes are randomly distributed into the vitellarium, although fully mature vitellocytes are found in the center of the follicle. During maturation, the nucleo-cytoplasmic ratio decreases, whereas synthetic activity increases. Fully mature vitellocytes are filled with β-glycogen particles and shell globule clusters. Compared to other trematodes studied, C. metoecus possesses a large amount of nutritive reserves for the developing embryo and high quantities of material for the developing shell. Oocyte maturation takes place in four stages: oogonia, primary oocytes, developing oocytes, and mature oocytes. Developing oocytes enter the zygotene-pachytene stage of the first meiotic division recognizable by the presence of synaptonemal complexes in the nucleoplasm. The low protein composition of mature oocytes associated with the large nutrient content of vitellocytes of C. metoecus enables us to consider that oocytes do not take part of the nutrition of the future embryo of the miracidium. A cytochemical test (Thiéry method) allowed us to detect the presence of polysaccharides and glycogen during maturation of these two cell types. PMID:27845028

  14. Sperm ultrastructure of the digenean Aphallus tubarium (Rudolphi, 1819) Poche, 1926 (Platyhelminthes, Cryptogonimidae) intestinal parasite of Dentex dentex (Pisces, Teleostei).

    PubMed

    Foata, J; Quilichini, Y; Greani, S; Marchand, B

    2012-02-01

    The ultrastructural organization of the spermatozoon of a cryptogonimid digenean, Aphallus tubarium, a parasite of Dentex dentex, is described. The spermatozoon possesses the elements found in other digeneans: two axonemes with 9+"1" pattern, a mitochondrion, a nucleus, cortical microtubules, external ornamentation and spine-like bodies. However, the mitochondrion appears as a cord with a bulge; this characteristic has never been described in other studied cryptogonimid and in other digeneans except in one lepocreadiid, Holorchis micracanthum. Likewise, the presence of a thin cytoplasm termination in the anterior part of the spermatozoon has never been pointed out in the cryptogonimids.

  15. Two new deep-reef basslets (Teleostei, Grammatidae, Lipogramma), with comments on the eco-evolutionary relationships of the genus

    PubMed Central

    Baldwin, Carole C.; Robertson, D. Ross; Nonaka, Ai; Tornabene, Luke

    2016-01-01

    Abstract The banded basslet, Lipogramma evides Robins & Colin, 1979, is shown to comprise two species: Lipogramma evides, which inhabits depths of 133–302 m, and a new species described here as Lipogramma levinsoni, which inhabits depths of 108–154 m and previously was considered to represent the juvenile of Lipogramma evides. A second new species of banded basslet, described here as Lipogramma haberi, inhabits depths of 152–233 m and was previously not reported in the literature. Morphologically, the three species differ in color patterns and modal numbers of gill rakers, whereas various other morphological features distinguish Lipogramma levinsoni from Lipogramma evides and Lipogramma haberi. DNA barcode data and multilocus, coalescent-based, species-delimitation analysis support the recognition of the three species. Phylogenetic analysis of mitochondrial and nuclear genetic data supports a sister-group relationship between the two deepest-living of the three species, Lipogramma evides and Lipogramma haberi, and suggests that the shallower Lipogramma levinsoni is more closely related to Lipogramma anabantoides Böhlke, 1960, which inhabits depths < 120 m. Evolutionary relationships within Lipogramma thus appear to be correlated with species depth ranges, an eco-evolutionary pattern that has been observed in other Caribbean marine teleosts and that warrants further investigation. The new species represent the eleventh and twelfth new fish species described in recent years from exploratory submersible diving in the Caribbean in the globally poorly studied depth zone of 50–300 m. This study suggests that there are at least two additional cryptic species of Lipogramma, which are being analyzed in ongoing investigations of Caribbean deep-reef ecosystems. PMID:28174497

  16. Melanin concentrating hormone (MCH) is involved in the regulation of growth hormone in Cichlasoma dimerus (Cichlidae, Teleostei).

    PubMed

    Pérez Sirkin, D I; Cánepa, M M; Fossati, M; Fernandino, J I; Delgadin, T; Canosa, L F; Somoza, G M; Vissio, P G

    2012-03-01

    Growth hormone (GH) is the main pituitary hormone involved in somatic growth. In fish, the neuroendocrine control of GH is multifactorial due to the interaction of multiple inhibitors and stimulators. Melanin-concentrating hormone (MCH) is a cyclic peptide involved in skin color regulation of fish. In addition, MCH has been related to the regulation of food intake in both mammals and fish. There is only one report presenting evidences on the GH release stimulation by MCH in mammals in experiments in vitro, but there are no data on non-mammals. In the present work, we report for the first time the sequence of MCH and GH cDNA in Cichlasoma dimerus, a freshwater South American cichlid fish. We detected contacts between MCH fibers and GH cells in the proximal pars distalis region of the pituitary gland by double label confocal immunofluorescence indicating a possible functional relationship. Besides, we found that MCH increased GH transcript levels and stimulated GH release in pituitary cultures. Additionally, C. dimerus exposed to a white background had a greater number of MCH neurons with a larger nuclear area and higher levels of MCH transcript than those fish exposed to a black background. Furthermore, fish reared for 3 months in a white background showed a greater body weight and total length compared to those from black background suggesting that MCH might be related to somatic growth in C. dimerus. Our results report for the first time, that MCH is involved in the regulation of the synthesis and release of GH in vitro in C. dimerus, and probably in the fish growth rate.

  17. Evidence of birth-and-death evolution of 5S rRNA gene in Channa species (Teleostei, Perciformes).

    PubMed

    Barman, Anindya Sundar; Singh, Mamta; Singh, Rajeev Kumar; Lal, Kuldeep Kumar

    2016-12-01

    In higher eukaryotes, minor rDNA family codes for 5S rRNA that is arranged in tandem arrays and comprises of a highly conserved 120 bp long coding sequence with a variable non-transcribed spacer (NTS). Initially the 5S rDNA repeats are considered to be evolved by the process of concerted evolution. But some recent reports, including teleost fishes suggested that evolution of 5S rDNA repeat does not fit into the concerted evolution model and evolution of 5S rDNA family may be explained by a birth-and-death evolution model. In order to study the mode of evolution of 5S rDNA repeats in Perciformes fish species, nucleotide sequence and molecular organization of five species of genus Channa were analyzed in the present study. Molecular analyses revealed several variants of 5S rDNA repeats (four types of NTS) and networks created by a neighbor net algorithm for each type of sequences (I, II, III and IV) did not show a clear clustering in species specific manner. The stable secondary structure is predicted and upstream and downstream conserved regulatory elements were characterized. Sequence analyses also shown the presence of two putative pseudogenes in Channa marulius. Present study supported that 5S rDNA repeats in genus Channa were evolved under the process of birth-and-death.

  18. Chromosomal Mapping of Repetitive DNAs in Characidium (Teleostei, Characiformes): Genomic Organization and Diversification of ZW Sex Chromosomes.

    PubMed

    Scacchetti, Priscilla C; Utsunomia, Ricardo; Pansonato-Alves, José C; Vicari, Marcelo R; Artoni, Roberto F; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    The speciose neotropical genus Characidium has proven to be a good model for cytogenetic exploration. Representatives of this genus often have a conserved diploid chromosome number; some species exhibit a highly differentiated ZZ/ZW sex chromosome system, while others do not show any sex-related chromosome heteromorphism. In this study, chromosome painting using a W-specific probe and comparative chromosome mapping of repetitive sequences, including ribosomal clusters and 4 microsatellite motifs - (CA)15, (GA)15, (CG)15, and (TTA)10 -, were performed in 6 Characidium species, 5 of which possessed a heteromorphic ZW sex chromosome system. The W-specific probe showed hybridization signals on the W chromosome of all analyzed species, indicating homology among the W chromosomes. Remarkably, a single major rDNA-bearing chromosome pair was found in all species. The 18S rDNA localized to the sex chromosomes in C. lanei, C. timbuiense and C. pterostictum, while the major rDNA localized to one autosome pair in C. vidali and C. gomesi. In contrast, the number of 5S rDNA-bearing chromosomes varied. Notably, minor ribosomal clusters were identified in the W chromosome of C. vidali. Microsatellites were widely distributed across almost all chromosomes of the karyotypes, with a greater accumulation in the subtelomeric regions. However, clear differences in the abundance of each motif were detected in each species. In addition, the Z and W chromosomes showed the differential accumulation of distinct motifs. Our results revealed variability in the distribution of repetitive DNA sequences and their possible association with sex chromosome diversification in Characidium species.

  19. Chirocentrodon bleekerianus (Teleostei: Clupeiformes: Pristigasteridae), a small predaceous herring with folded and distinctively oriented prey in stomach.

    PubMed

    Sazima, C; Moura, R L; Sazima, I

    2004-02-01

    Predaceous fish-eating species of the order Clupeiformes have a large mouth with well-developed teeth, and reach the greatest sizes within their families (up to 90 cm). We found that the pristigasterid Chirocentrodon bleekerianus, a small clupeiform (about 10 cm) from the tropical SW Atlantic, is able to prey on proportionally large clupeoid fishes and caridean shrimps. Fish preys are folded in the stomach of this herring, their heads and tails pointing toward the predator's head. This distinctive orientation of fish prey is also recorded for some small to medium-sized, fish-eating species of the tropical freshwater order Characiformes with canine-like teeth similar to those found in C. bleekerianus.

  20. Functional morphology of digestion in the stomachless, piscivorous needlefishes Tylosurus gavialoides and Strongylura leiura ferox (Teleostei: Beloniformes).

    PubMed

    Manjakasy, Jennifer M; Day, Ryan D; Kemp, Anne; Tibbetts, Ian R

    2009-10-01

    Belonidae are unusual in that they are carnivorous but lack a stomach and have a straight, short gut. To develop a functional morphological model for this unusual system the gut contents and alimentary tract morphology of Tylosurus gavialoides and Strongylura leiura ferox were investigated. The posterior orientation of the majority of the pharyngeal teeth supports the swallowing of whole large prey, but not their mastication. Mucogenic cells are abundant in the mucosa lining, particularly the esophagus, and their secretions are likely to protect the gut lining from damage while lubricating passage of the prey. Esophagus, anterior intestine, posterior intestine, and rectum all have highly reticulate mucosae. The anterior three gut sections are distensible to accommodate the passage of prey. However, following ingestion large prey are passed to the highly distensible posterior intestine where they rest head first against the ileorectal valve. Alimentary pH ranges from neutral to weakly acidic. Fish prey is digested head first with the head being largely digested while the remainder of the body is still intact. The nondistensibility of the rectum and the small aperture provided by the ileorectal valve suggest the products of intestinal digestion are either small particulates or fluids that pass into rectum where they are absorbed.

  1. The role of steroid hormones in protogynous sex change in the Blackeye goby, Coryphopterus nicholsii (Teleostei: Gobiidae).

    PubMed

    Kroon, F J; Liley, N R

    2000-05-01

    To detect and describe correlations between steroid concentrations and sexual function in the protogynous Coryphopterus nicholsii, we examined whole-body concentrations of the gonadal steroids testosterone (T), 11-ketotestosterone (11-KT), and 17beta-estradiol (17beta-E2). Our results show that T, 11-KT, and 17beta-E2 are naturally occurring steroids in both female and male C. nicholsii. Further, mean whole-body concentrations of T and 11-KT in males were approximately twice those in females, whereas mean whole-body concentration of 17beta-E2 in females was almost twice that in males. Second, we tested hypotheses on the causation of sex change arising from these correlations between steroid concentrations and sexual function. We examined the effects of administration of 11-KT, 11-KA, 17alpha-methyltestosterone, and an aromatase inhibitor (Fadrozole) on gonadal structures of mature females. Complete sex change was induced by 11-KT, 11-KA, and Fadrozole. Our results strongly suggest that an increase in 11-KT concentration and perhaps also a decrease in 17beta-E2 concentration are involved in mediating natural sex change in C. nicholsii.

  2. Neoplecostomus doceensis: a new loricariid species (Teleostei, Siluriformes) from the rio Doce basin and comments about its putative origin.

    PubMed

    Roxo, Fábio F; Silva, Gabriel S C; Zawadzki, Cláudio H; Oliveira, Claudio

    2014-01-01

    A new species of Neoplecostomus is described from the rio Doce basin representing the first species of this genus in the basin. The new species is distinguished from its congeners by having enlarged, fleshy folds between dentaries, two or three series of developed papillae anterior to premaxillary teeth and a adipose-fin membrane present, and by lacking enlarged odontodes along snout lateral margins in mature males, a well-developed dorsal-fin spinelet wider than dorsal-fin spine base, lower number of lateral-line figs and developed membrane on the dorsal portion of the first, second and third pelvic-fin branched rays. Additionally, we present a brief discussion of biogeographic scenarios that may explain the distribution of the new species in the rio Doce basin. We suggested that the ancestral lineage of the new species reached the rio Doce from the upper portions of rio Paraná drainages about 3.5 Mya (95% HPD: 1.6-5.5) indicating a colonization route of the N. doceensis ancestral lineage from the south end of Serra do Espinhaço, probably as a result of headwater capture processes between the upper rio Paraná and rio Doce basins.

  3. Plectranthias takasei, new species of anthiadine fish from southern Japan (Teleostei: Serranidae).

    PubMed

    Gill, Anthony C; Tea, Yi-Kai; Senou, Hiroshi

    2016-12-07

    Plectranthias takasei is described from two specimens collected in Izu Oceanic Park, Sagami Bay, Honshu, Japan. It is distinguished from congeners in having the following combination of characters: dorsal rays X,15; no fleshy flaps on dorsal-fin spines; pectoral rays 13, all unbranched; branched caudal-fin rays 8 + 7; lateral line scales 28 (including intermittent and terminal pitted scales); circumpeduncular scales 12; fourth dorsal-fin spine longest; and preopercle without antrorse spines or serrations ventrally, with 2-3 weak serrations or crenulations posteriorly.

  4. Mitogenomic evidence for the monophyly of elopomorph fishes (Teleostei) and the evolutionary origin of the leptocephalus larva.

    PubMed

    Inoue, Jun G; Miya, Masaki; Tsukamoto, Katsumi; Nishida, Mutsumi

    2004-07-01

    The monophyly of Elopomorpha (eels and their relatives) has long been one of the most problematic issues in systematic ichthyology. Since established the Elopomorpha based on the existence of the leaf-like larval form, termed a leptocephalus, no one has corroborated their monophyly using character matrices derived from both morphological and molecular data during the last 30 years. We investigated their monophyly and interrelationships at the ordinal level using complete mitochondrial genomic (mitogenomic) data from 33 purposefully chosen species (data for nine species being newly determined during the study) that fully represent the major teleostean and elopomorph lineages. Partitioned Bayesian analyses were conducted with the two data sets that comprised concatenated nucleotide sequences from 12 protein-coding genes (with and without third codon positions), 22 transfer RNA genes, and two ribosomal RNA genes. The resultant trees were well resolved and largely congruent, with most internal branches being supported by high statistical values. Mitogenomic data strongly supported the monophyly of Elopomorpha, indicating the validity of the leptocephalus as an elopomorph synapomorphy. The order Elopiformes occupied the most basal position in the elopomorph phylogeny, with the Albuliformes and a clade comprising the Anguilliformes and the Saccopharyngiformes forming a sister group. The most parsimonious reconstruction of the three previously recognized, distinct larval types of elopomorphs onto the molecular phylogeny revealed that one of the types (fork-tailed type) had originated as the common ancestor of the Elopomorpha, the other two (filament-tailed and round-tailed types) having diversified separately in two more derived major clades.

  5. A southern species of the tropical catfish genus Phractocephalus (Teleostei: Siluriformes) in the Miocene of South America

    NASA Astrophysics Data System (ADS)

    Azpelicueta, María de las Mercedes; Cione, Alberto Luis

    2016-04-01

    Catfish bones from Tortonian (Miocene) freshwater beds of central Argentina are here identified as pertaining to a new species of the tropical pimelodid genus Phractocephalus. The new species differs from the other recent and fossil species of the genus in skull, pectoral girdle and spine characters. The material was found in different localities near the city of Paraná, Entre Ríos Province. The bearing horizon is the so-called "Conglomerado osífero" which constitutes the lowermost beds of the fluvial Ituzaingó Formation. The aquatic vertebrate fauna occurring in the bearing bed shows a similar generic composition to several northern South American Miocene units where Phractocephalus remains were found. This report extends the range of Phractocephalus more than 2000 km to the South. The record is in agreement with higher global temperatures and putative ample hydrographic connections of the river basins in the Paraná area with the Amazon basin until at least the early late Miocene.

  6. Capoeta anamisensis, a new species from the Minab and Hasan Langhi River drainages in Iran (Teleostei: Cyprinidae).

    PubMed

    Zareian, Halimeh; Esmaeili, Hamid Reza; Freyhof, Jörg

    2016-02-18

    Capoeta anamisensis, from the Minab and Hasal Langhi River drainages in southern Iran, belongs to the C. trutta species group. Capoeta anamisensis is distinguished from other species of the C. trutta species group by the combination of the following characters: flank silvery without black spots; 56-67 scales in total along the lateral series; 11-12 scales above the lateral line and 21-25 gill rakers. Capoeta anamisensis is also distinguished from all other congeners in the Persian Gulf basin by having four fixed, diagnostic nucleotide substitutions in the mtDNA COI barcode region and five fixed, diagnostic nucleotide substitutions in the mtDNA cyt b region. The type of Capoeta barroisi persica is identified as an aberrant individual of C. trutta and is considered as a synonym of that species.

  7. Vascularization of male gonads in Blennius pavo (Teleostei, Blenniidae) as revealed by scanning electron microscopy of vascular corrosion casts.

    PubMed

    Lahnsteiner, F; Lametschwandtner, A; Patzner, R A; Adam, H

    1988-12-01

    The vascular architecture of male gonads of Blennius pavo is studied by scanning electron microscopy of vascular corrosion casts. Arterial supply to the gonads is by a branch of the first ventral segmental artery of the tail. From the surface of the gonads, this vessel gives rise to branches which supply testes, spermatic ducts, testicular glands, blind pouches, urogenital sinus and urogenital papilla. The testis has a rope-ladder-like capillary network around the seminiferous tubules, while in the testicular gland the capillary network is irregular in form. The spermatic ducts are found to have an exterior capillary network located in the compact connective tissue layer and an interior one, lying subepithelially. Urogenital sinus and urogenital papilla show a multilayered capillary network. Angioarchitecture in mature and immature gonads does not differ.

  8. Before the freeze: otoliths from the Eocene of Seymour Island, Antarctica, reveal dominance of gadiform fishes (Teleostei)

    PubMed Central

    Schwarzhans, Werner; Mörs, Thomas; Engelbrecht, Andrea; Reguero, Marcelo; Kriwet, Jürgen

    2017-01-01

    The first record of fossil teleostean otoliths from Antarctica is reported. The fossils were obtained from late Early Eocene shell beds of the La Meseta Formation, Seymour Island that represent the last temperate marine climate phase in Antarctica prior to the onset of cooling and subsequent glaciation during the late Eocene. A total of 17 otolith-based teleost taxa are recognized, with 10 being identifiable to species level containing nine new species and one new genus: Argentina antarctica sp. nov., Diaphus? marambionis sp. nov., Macruronus eastmani sp. nov., Coelorinchus balushkini sp. nov., Coelorinchus nordenskjoeldi sp. nov., Palimphemus seymourensis sp. nov., Hoplobrotula? antipoda sp. nov., Notoberyx cionei gen. et sp. nov. and Cepola anderssoni sp. nov. Macruronus eastmani sp. nov. is also known from the late Eocene of Southern Australia, and Tripterophycis immutatus Schwarzhans, widespread in the southern oceans during the Eocene, has been recorded from New Zealand, southern Australia, and now Antarctica. The otolith assemblage shows a typical composition of temperate fishes dominated by gadiforms, very similar at genus and family levels to associations known from middle Eocene strata of New Zealand and the late Eocene of southern Australia, but also to the temperate Northern Hemisphere associations from the Paleocene of Denmark. The Seymour Island fauna bridges a gap in the record of global temperate marine teleost faunas during the early Eocene climate maximum. The dominant gadiforms are interpreted as the main temperate faunal component, as in the Paleocene of Denmark. Here they are represented by the families Moridae, Merlucciidae (Macruroninae), Macrouridae and Gadidae. Nowadays Gadidae are a chiefly Northern Hemisphere temperate family. Moridae, Macruroninae and Macrouridae live today on the lower shelf to deep-water or mesopelagically with Macruroninae being restricted to the Southern Ocean. The extant endemic Antarctic gadiform family Muraenolepididae is missing, as are the dominant modern Antarctic fishes of the perciform suborder Notothenioidei. Recently, there has been much debate on isolated jaw bones of teleost fishes found in the La Meseta Formation and whether they would represent gadiforms (Merlucciidae in this case) or some early, primitive notothenioid. Otoliths are known to often complement rather than duplicate skeletal finds. With this in mind, we conclude that our otolith data support the presence of gadiforms in the early Eocene of Antarctica while it does not rule out the presence of notothenioids at the same time. http://zoobank.org/urn:lsid:zoobank.org:pub:A30E5364-0003-4467-B902-43A41AD456CC PMID:28077930

  9. The role of continental shelf width in determining freshwater phylogeographic patterns in south-eastern Australian pygmy perches (Teleostei: Percichthyidae).

    PubMed

    Unmack, Peter J; Hammer, Michael P; Adams, Mark; Johnson, Jerald B; Dowling, Thomas E

    2013-03-01

    Biogeographic patterns displayed by obligate freshwater organisms are intimately related to the nature and extent of connectivity between suitable habitats. Two of the more significant barriers to freshwater connections are seawater and major drainage divides. South-eastern Australia provides a contrast between these barriers as it has discrete areas that are likely influenced to a greater or lesser extent by each barrier type. We use continental shelf width as a proxy for the potential degree of river coalescence during low sea levels. Our specific hypothesis is that the degree of phylogeographic divergence between coastal river basins should correspond to the continental shelf width of each region. This predicts that genetic divergences between river basins should be lowest in regions with a wider continental shelf and that regions with similar continental shelf width should have similar genetic divergences. Pygmy perches (Nannoperca australis and Nannoperca 'flindersi') in south-eastern Australia provide an ideal opportunity to test these biogeographic hypotheses. Phylogeographic patterns were examined based on range-wide sampling of 82 populations for cytochrome b and 23 polymorphic allozyme loci. Our results recovered only limited support for our continental shelf width hypothesis, although patterns within Bass clade were largely congruent with reconstructed low sea-level drainage patterns. In addition, we identified several instances of drainage divide crossings, typically associated with low elevational differences. Our results demonstrate high levels of genetic heterogeneity with important conservation implications, especially for declining populations in the Murray-Darling Basin and a highly restricted disjunct population in Ansons River, Tasmania.

  10. The involvement of gonadotropins and gonadal steroids in the ovulatory dysfunction of the potamodromous Salminus hilarii (Teleostei: Characidae) in captivity.

    PubMed

    Moreira, Renata Guimarães; Honji, Renato Massaaki; Melo, Renato Garcia; Narcizo, Amanda de Moraes; Amaral, Juliane Suzuki; Araújo, Ronaldo de Carvalho; Hilsdorf, Alexandre Wagner Silva

    2015-12-01

    Potamodromous teleosts that require migration to reproduce show dysfunctions that block ovulation and spawning while in captivity. To understand the physiological basis of these reproductive dysfunctions, follicle-stimulating hormone b subunit (fshb) and luteinizing hormone b subunit (lhb) gene expression analyses by real-time quantitative PCR, together with measurements of estradiol (E 2), 17α-hydroxyprogesterone (17α-OHP) and 17α,20β-dihydroxy-4-pregnen-3-one (17α,20β-DHP) levels, were carried out throughout the reproductive cycle of the potamodromous Salminus hilarii. The following reproductive stages were evaluated in captive and wild females: previtellogenic (PV), advanced maturation/mature (AM) and regression/spent (REG/SPENT). In the wild females, fshb expression decreased from the PV to the AM stage, and the opposite pattern was detected for E 2, which increased from the PV to the AM stage. fshb was expressed at lower levels in captive than in wild females, and this difference did not change during the reproductive cycle. lhb expression also increased from the PV to the AM stage in both groups, but the wild females at the AM and REG/SPENT stages showed higher lhb expression levels than the captive females. The concentrations of 17α-OHP did not change during the reproductive cycle, and the levels were higher in the captive than in the wild females at all reproductive stages. 17α,20β-DHP levels did not change between wild and captive females. However, in captive females, the transition from PV to AM stage was followed by an increase in 17α,20β-DHP levels. These data indicate that dysfunctions in the gonadotropins and steroids synthesis pathways cause the ovulation failure in captive S. hilarii.

  11. A new species of Pachycara Zugmayer, 1911 (Teleostei: Zoarcidae) from deep-sea chemosynthetic environments in the Caribbean Sea.

    PubMed

    Anderson, M Eric; Somerville, Russell; Copley, Jonathan T

    2016-01-12

    The 28th species of the eelpout genus Pachycara Zugmayer, 1911, is described from specimens collected from an active hydrothermal vent field at a depth of about 2300 m at the Mid-Cayman Spreading Centre of the Caribbean Sea. A tentatively identified early juvenile is recorded at a methane seep at a depth of 1049 m near Tobago. The new species is distinguished from its congeners mainly by its few pectoral fin rays, low vertebral counts, single, mediolateral branch of the lateral line system and presence of scales on the nape and cheeks.

  12. Phylogenetic position of the Dalmatian genus Phoxinellus and description of the newly proposed genus Delminichthys (Teleostei: Cyprinidae).

    PubMed

    Freyhof, Jörg; Lieckfeldt, Dietmar; Bogutskaya, Nina G; Pitra, Christian; Ludwig, Arne

    2006-02-01

    The Dalmatian cyprinid genus Phoxinellus is characterized by reductive characters most likely associated with the environmental conditions of small karstic streams, where all species of this genus occur. Based on 33 morphological traits, nuclear and mtDNA sequences Phoxinellus was found to be paraphyletic and included three not closely related monophyletic units. The scientific name Phoxinellus should therefore be restricted to species having plain coloration, small or absent postcleithrum, no genital papilla and an almost entirely naked body such as P. alepidotus, P. dalmaticus, and P. pseudalepidotus. Species that also have a small or absent postcleithrum and no genital papilla but display a dark stripe from the head to the caudal peduncle, and are entirely covered by distinct, not overlapping scales should be positioned closely to Telestes. Thus, we suggest inclusion of Phoxinellus croaticus, P. fontinalis and Paraphoxinus metohiensis in the genus Telestes. The Phoxinellus species that have a irregularly spotted color pattern, a large postcleithrum, an increased number of precaudal anal-fin pterygiophores, and a large genital papilla in females represent its own evolutionary line closely related to the Balkan species of Pseudophoxinus. For this monophyletic group, we propose to introduce a new genus: Delminichthys. This genus includes the species D. adspersus, D. ghetaldii, D. krbavensis and D. jadovensis.

  13. Loss of genetic diversity at an MHC locus in the endangered Tokyo bitterling Tanakia tanago (Teleostei: Cyprinidae).

    PubMed

    Kubota, Hitoshi; Watanabe, Katsutoshi

    2013-12-01

    Genetic diversity at a major histocompatibility complex (MHC) class II B gene was examined for two wild and three captive populations of the endangered Tokyo bitterling Tanakia tanago. A specific primer set was first developed to amplify the MHC II B exon 2 locus. Using single strand conformation polymorphism (SSCP) and sequencing analysis, 16 DAB3 alleles were detected with 56 nucleotide substitutions in the 276-bp region. In the putative antigen-binding sites of exon 2, the rate of nonsynonymous substitutions was significantly higher than that of synonymous substitutions (dN/dS = 2.79), indicating positive selection on the retention of polymorphism. The population from the Handa Natural Habitat Conservation Area and that from the Tone River system exhibited low variation (one and three alleles, respectively), whereas the captive population that originated from a mix of three distinct populations had the highest amounts of variation (14 alleles). The levels of heterozygosity at the MHC varied considerably among populations and showed significant correlations with those at putative neutral microsatellite markers, suggesting that genetic drift following a bottleneck has affected MHC variability in some populations. Comparisons between endangered and non-endangered fish species in previous reports and the present results indicate that the number of MHC alleles per population is on average 70% lower in endangered species than non-endangered species. Considering the functional consequence of this locus, attention should be paid to captive and wild endangered fish populations in terms of further loss of MHC alleles.

  14. Cryptomyrus: a new genus of Mormyridae (Teleostei, Osteoglossomorpha) with two new species from Gabon, West-Central Africa

    PubMed Central

    Sullivan, John P.; Lavoué, Sébastien; Hopkins, Carl D.

    2016-01-01

    Abstract We use mitochondrial and nuclear sequence data to show that three weakly electric mormyrid fish specimens collected at three widely separated localities in Gabon, Africa over a 13-year period represent an unrecognized lineage within the subfamily Mormyrinae and determine its phylogenetic position with respect to other taxa. We describe these three specimens as a new genus containing two new species. Cryptomyrus, new genus, is readily distinguished from all other mormyrid genera by a combination of features of squamation, morphometrics, and dental attributes. Cryptomyrus ogoouensis, new species, is differentiated from its single congener, Cryptomyrus ona, new species, by the possession of an anal-fin origin located well in advance of the dorsal fin, a narrow caudal peduncle and caudal-fin lobes nearly as long as the peduncle. In Cryptomyrus ona, the anal-fin origin is located only slightly in advance of the dorsal fin, the caudal peduncle is deep and the caudal-fin lobes considerably shorter than the peduncle. Continued discovery of new taxa within the “Lower Guinea Clade” of Mormyridae highlights the incompleteness of our knowledge of fish diversity in West-Central Africa. We present a revised key to the mormyrid genera of Lower Guinea. PMID:27006619

  15. Trilosporoides platessae gen. et sp. n. (Myxozoa: Multivalvulida) in the plaice Pleuronectes platessa (Teleostei: Pleuronectidae) from Denmark.

    PubMed

    Køie, Marianne

    2005-11-01

    A new myxosporean species, Trilosporoides platessae gen. et sp. n. (Multivalvulida), is described from the gallbladder of the plaice Pleuronectes platessa L. (Pleuronectidae) from Denmark. The myxospore of T. platessae is conical in side view, with a 24 microm long, pointed posterior projection. In apical view, the myxospore (diameter 9.4 microm) is round, trilobed and with three spherical polar capsules arranged peripherally, equidistant and opening peripherally through protruding tips. The polar capsules are of different sizes, one often larger than the others (diameter 3.3 microm vs. 2.5 microm). Apart from the long posterior projection, the myxospore of T. platessae differs from those of the three known species of Trilospora Noble, 1959 and from all genera within the order Multivalvulida Shulman, 1959 in the arrangement of the polar capsules. Trilosporoides platessae may temporarily be placed in the vicinity of the Trilosporidae.

  16. New insights into the complex structure and ontogeny of the occipito-vertebral gap in barbeled dragonfishes (Stomiidae, Teleostei).

    PubMed

    Schnell, Nalani K; Britz, Ralf; Johnson, G David

    2010-08-01

    In all stomiid genera there is an occipito-vertebral gap between the skull and the first vertebra bridged only by the flexible notochord. Morphological studies from the early 20th century suggested that some stomiid genera have 1-10 of the anteriormost centra reduced or entire vertebrae missing in this region. Our study reviews this previous hypothesis. Using a new approach, we show that only in Chauliodus, Eustomias and Leptostomias gladiator vertebral centra are actually lost, with their respective neural arches and parapophyses persisting. We present results from a comparative analysis of the number and insertion sites of the anteriormost myosepta in 26 of the 28 stomiid genera. Generally in teleosts the first three myosepta are associated with the occiput, and the fourth is the first vertebral myoseptum. The insertion site of the fourth myoseptum plays an important role in this analysis, because it provides a landmark for the first vertebra. Lack of association of the fourth myoseptum with a vertebra is thus evidence that the first vertebra is reduced or absent. By counting the occipital and vertebral myosepta the number of reduced vertebrae in Chauliodus, Eustomias and Leptostomias gladiator can be inferred. Proper identification of the spino-occipital nerves provides an additional source of information about vertebral reduction. In all other stomiid genera the extensive occipito- vertebral gap is not a consequence of the reduction of vertebrae, but of an elongation of the notochord. The complex structure and ontogeny of the anterior part of the vertebral column of stomiids are discussed comparatively.

  17. Peripatric differentiation among adjacent marine lake and lagoon populations of a coastal fish, Sphaeramia orbicularis (Apogonidae, Perciformes, Teleostei).

    PubMed

    Gotoh, Ryo O; Sekimoto, Hidekatsu; Chiba, Satoru N; Hanzawa, Naoto

    2009-08-01

    The effect of geographical isolation on speciation, particularly within short geographical ranges, is poorly understood among marine organisms. Focusing on marine lakes of the Palau Islands, we investigated the effect of geographical isolation on Sphaeramia orbicularis, a coastal fish inhabiting marine lakes and lagoons. We collected a total of 157 individuals from three meromictic marine lakes and three lagoon sites, and analyzed the genetic diversity and differentiation of the populations based on complete sequences of the mitochondrial control region (824 bp). The analyses show that the genetic diversity of marine lake populations is much lower than that of lagoon populations. Moreover, a mismatch distribution analysis suggests that marine lake populations have experienced a decrease followed by a rapid expansion of their population size. These results reveal that marine lake populations have experienced severe founder and/or bottleneck events during the last thousand to tens of thousand years. Pairwise Phi(ST )values ranged from 0.531 to 0.848 between marine lake and lagoon populations and from 0.429 to 0.870 among marine lake populations, indicating a high degree of genetic differentiation. We speculate that such peripatric differentiation between marine lake and lagoon populations was caused by a small number of individuals colonizing the lakes from the lagoon (founder event) followed by repetitive bottleneck events, such as those generated by the El Niño-Southern Oscillation (ENSO). So far, such high genetic divergences in extremely short geographical ranges (approximately 150-250 m) have scarcely been reported for marine organisms. We suggest that the marine lake is one of the good model of geographical isolation in marine organisms and each marine lake population is in the early stages of speciation.

  18. ZZ/ZW sex chromosome system in the endangered fish Lignobrycon myersi Miranda-Ribeiro, 1956 (Teleostei, Characiformes, Triportheidae)

    PubMed Central

    Rodrigues, Alexandre dos Santos; Medrado, Aline Souza; Diniz, Débora; Oliveira, Claudio; Affonso, Paulo Roberto Antunes de Mello

    2016-01-01

    Abstract Lignobrycon myersi is an endemic fish species from a few coastal rivers in northeastern Brazil. Based on molecular evidence, Lignobrycon myersi and genera Triportheus Cope, 1872, Agoniates Müller & Troschel, 1845, Clupeacharax Pearson, 1924 and Engraulisoma Castro, 1981 were placed in the family Triportheidae. In the present work, we report the first cytogenetic data for Lignobrycon myersi to test the hypothesis that Lignobrycon and Triportheus are closely related. Studied specimens presented 2n=52 with 28 metacentric (m), 18 submetacentric (sm) and six subtelocentric (st) chromosomes for males and 27 m, 19 sm and 6 st for females, characterizing a ZZ/ZW sex chromosome system. The Z chromosome corresponds to the largest chromosome in karyotype while the W is about 50% smaller than the Z and largely heterochromatic. Terminal nucleolus organizer regions, GC-rich sites and 18S rDNA signals were detected on pair 14. However, additional 18S rDNA sites were observed in the W chromosome. The 5S rDNA was mainly detected on long arms of pair 7. The apparent synapomorphic chromosomal traits of Triportheus and Lignobrycon myersi reinforce their close phylogenetic relationship, suggesting that the ZZ/ZW chromosome system in both genera has arisen before cladogenic events. PMID:27551346

  19. Postglacial recolonization of eastern Blacknose Dace,Rhinichthys atratulus(Teleostei: Cyprinidae), through the gateway of New England

    PubMed Central

    Tipton, Michelle L; Gignoux-Wolfsohn, Sarah; Stonebraker, Phoebe; Chernoff, Barry

    2011-01-01

    During the last ice age, much of North America far south as 40°N was covered by glaciers (Hewitt 2000). About 20,000 years ago, as the glaciers retreated, the hydrologic landscape changed dramatically creating waterways for fish dispersal. The number of populations responsible for recolonization and the regions from which they recolonized are unknown for many freshwater fishes living in New England and southeastern Canada. The Blacknose Dace,Rhinichthys atratulus, is one of the freshwater fish species that recolonized this region. We hypothesize that the earliest deglaciated region, modern-day Connecticut, was recolonized byR. atratulusvia a single founding event by a single population. In this paper, we test this hypothesis phylogenetically with regard to the major drainage basins within Connecticut. The mitochondrial DNA exhibits low nucleotide diversity, high haplotype diversity, and a dominant haplotype found across the state. A small percentage of individuals in the Housatonic drainage basin, however, share a haplotype with populations in New York drainage basins, a haplotype not found elsewhere in Connecticut's drainage basins. We calculated a range for the rate of divergence for NADH dehydrogenase subunit 2 (nd2) and control region (ctr) of 4.43–6.76% and 3.84–8.48% per million years (my), respectively. While this range is higher than the commonly accepted rate of 2% for mitochondrial DNA, these results join a growing list of publications finding high rates of divergence for various taxa (Peterson and Masel 2009). The data support the conclusion that Connecticut as a whole was recolonized initially by a single founding event that came from a single refugium. Subsequently, the Housatonic basin alone experienced a secondary recolonization event. PMID:22393505

  20. Two new species of Oxynoemacheilus from the Tigris drainage in Iraqi Kurdistan (Teleostei: Nemacheilidae).

    PubMed

    Freyhof, Jörg; Abdullah, Younis Sabir

    2017-03-02

    Two new species of Oxynoemacheilus are described from the Sirvan River drainage in Iraqi Kurdistan. Oxynoemacheilus gyndes, new species, is distinguished by having a very short lateral line, reaching behind the pectoral-fin base, no scales except on the posteriormost part of the caudal peduncle, a slightly emarginate caudal fin and no suborbital groove in males. Oxynoemacheilus hanae, new species, is distinguished by having a midlateral row of elongated blotches, isolated patches of dark-brown spots or blotches on lower flank, a deeply emarginate caudal fin and a suborbital groove in males.

  1. Review of the crevalle jacks, Caranx hippos complex (Teleostei: Carangidae), with a description of a new species from West Africa

    USGS Publications Warehouse

    Smith-Vaniz, W.F.; Carpenter, K.E.

    2007-01-01

    The Caranx hippos species complex comprises three extant species: crevalle jack (Caranx hippos) (Linnaeus, 1766) from both the western and eastern Atlantic oceans; Pacific crevalle jack (Caranx caninus) Gu??nther, 1868 from the eastern Pacific Ocean; and longfin crevalle jack (Caranx fischeri) new species, from the eastern Atlantic, including the Mediterranean Sea and Ascension Island. Adults of all three species are superficially similar with a black blotch on the lower half of the pectoral fin, a black spot on the upper margin of opercle, one or two pairs of enlarged symphyseal canines on the lower jaw, and a similar pattern of breast squamation. Each species has a different pattern of hyperostotic bone development and anal-fin color. The two sympatric eastern Atlantic species also differ from each other in number of dorsal- and anal-fin rays, and in large adults of C. fischeri the lobes of these fins are longer and the body is deeper. Caranx hippos from opposite sides of the Atlantic are virtually indistinguishable externally but differ consistently in the expression of hyperostosis of the first dorsal-fin pterygiophore. The fossil species Caranx carangopsis Steindachner 1859 appears to have been based on composite material of Trachurus sp. and a fourth species of the Caranx hippos complex. Patterns of hyperostotic bone development are compared in the nine (of 15 total) species of Caranx sensu stricto that exhibit hyperostosis.

  2. Experimentally induced pigment changes in small African 'Barbus' (Teleostei: Cyprinidae): Synonymy of 'Barbus' amphigramma and 'Barbus' taitensis with 'Barbus' paludinosus

    USGS Publications Warehouse

    Farm, Brian P.

    2001-01-01

    Pigmentation in fishes is known to be variable both among individuals of a species and within individuals over time. Use of pigment characters for taxonomic diagnoses must, therefore, be carefully considered. I present experimental evidence showing that pigment characters previously considered diagnostic for three small African 'Barbus' species may differ between living and preserved specimens and that lasting changes in these characters can be induced experimentally by placing fishes in a different, less turbid environment. Lateral line pigmentation and presence of a spot on the caudal peduncle showed significant changes that resulted in different species identifications before and after the experiment. These pigment patterns are thereby shown to be labile, nontrenchant characters having little or no diagnostic utility. 'Barbus' amphigramma Boulenger, 1903, and 'Barbus' taitensis Gu??nther, 1894, are thus shown to be junior synonyms of 'Barbus' paludinosus Peters, 1852.

  3. Allozyme relationships in hypostomines (Teleostei: Loricariidae) from the Itaipu Reservoir, Upper Rio Paraná basin, Brazil.

    PubMed

    Zawadzki, Cláudio Henrique; Renesto, Erasmo; dos Reis, Roberto Esser; Moura, Maurício Osvaldo; Mateus, Rogério Pincela

    2005-03-01

    In an allozyme electrophoresis survey of 15 hypostomine species from the Itaipu Hydroelectric Reservoir, 25 loci from 14 enzyme systems were scored. Allozyme data allowed recording diagnostic genetic markers for all species analyzed and for some species groups within Hypostomus, a taxon which is taxonomically still unresolved in the Upper Rio Paraná basin. The mean expected heterozygosity of the species was considerably variable and hypotheses to tentatively explain this variation are discussed. A cladogram based upon the allelic frequencies of the species analyzed was produced by the continuous maximum likelihood method: Rhinelepis aspera and M. parananus were separated from the species of Hypostominae by a long branch length. Pterygoplichthys anisitsi was the sister of all the representatives of the genus Hypostomus. Within Hypostomus, two main clades were produced: in the first, H. cochliodon was the sister of the species comprising the H. plecostomus group, and in the second, the tree showed the following relationships: (H. albopunctatus (H. regani + Hypostomus sp. 3) + (H. margaritifer (H. microstomus (Hypostomus sp. 1 (H. ternetzi + Hypostomus sp. 2)). Hypostomus ternetzi and Hypostomus sp. 2 are referred to here as representatives of the H. ternetzi group.

  4. Fishery of the Goliath grouper, Epinephelus itajara (Teleostei: Epinephelidae) based on local ecological knowledge and fishery records in Yucatan, Mexico.

    PubMed

    Aguilar-Perera, Alfonso; González-Salas, Carlos; Tuz-Sulub, Armin; Villegas-Hernández, Harold

    2009-09-01

    The Goliath grouper, Epinephelus itajara, a large-bodied (approximately 2.5 m TL, > 400 kg) and critically endangered fish (Epinephelidae), is highly vulnerable to overfishing. Although protected from fishing in many countries, its exploitation in Mexico is unregulated; a situation that puts its populations at risk. Fishery records of E. itajara are scarce, which prevents determination of its fishery status. This work aimed to elucidate the E. itajara fishery in the northern Yucatan Peninsula by 1) analyzing available catch records and 2) interviewing veteran fishermen (local ecological knowledge) from two traditional landing sites: Dzilam de Bravo and Puerto Progreso. Historic fishery records from two fishing cooperatives were analyzed in order to elucidate the current situation and offer viable alternatives for conservation and management. Catches have decreased severely. Local knowledge obtained from fishermen represented a very important source of information for reconstructing the fisheries history of this species. Conservation measures that incorporate regional and international regulations on critically endangered fish species are suggested.

  5. A review of the Callogobius (Teleostei: Gobiidae) from the Red Sea with the description of a new species.

    PubMed

    Delventhal, Naomi R; Mooi, Randall D; Bogorodsky, Sergey V; Mal, Ahmad O

    2016-10-31

    Five species of Callogobius Bleeker have been previously reported from the Red Sea: C. amikami Goren, Miroz & Baranes, C. clarki (Goren), C. dori Goren, C. flavobrunneus (Smith), and C. maculipinnis (Fowler). Records of C. bifasciatus (Smith) in the Red Sea are referable to C. clarki. Callogobius amikami has been previously known only from a single specimen, the holotype from the Red Sea, and two photographs, a live juvenile from Oman and a live specimen at an aquarium at Coral World, Eilat. We obtained a possible additional juvenile from the Red Sea, although we are unable to definitively determine its identity. Red Sea specimens previously identified as C. maculipinnis [or C. irrasus (Smith)] represent a new species, distinguished from the latter by normally having four sets of transverse mandibular rows on each side (rather than three); this species is described here as Callogobius pilosimentum sp. nov. Four specimens of an additional, undescribed species of Callogobius, C. sp. A, have been collected from the Red Sea, but we withhold a formal description because this species is currently under study by colleagues. Callogobius sclateri (Steindachner), previously known from the Indo-West Pacific, is reported from the Red Sea for the first time. A key to all seven species is provided. Each species is photographed, habitat is described and a brief description with detailed comparisons is provided. The new species and C. clarki are endemic to the Red Sea.

  6. Brycon gouldingi (Teleostei, Characidae): aspects of the embryonic development in a new fish species with aquaculture potential.

    PubMed

    Faustino, Francine; Nakaghi, Laura Satiko Okada; Neumann, Erika

    2011-11-01

    Brycon gouldingi is an endemic species from Tocantins-Araguaia basin, used as a food source by riverine communities and relevant to aquaculture. Information about the initial morphology of B. gouldingi, a recently described species, is absent. In the present study, we analysed the fertilization and the embryonic development of this species based on light and scanning electron microscopy. After collection of adult specimens in Mortes River - Mato Grosso, Brazil, adaptation to captivity and induced spawning at Buriti Fishculture, Nova Mutum - Mato Grosso, Brazil, in December 2007 and January 2008, samples were collected at pre-defined periods from egg extrusion up to larval hatching, which occurred at 13.9 ± 0.06 h post-fertilization (hpf) in average. At the moment of extrusion, the eggs were slightly ovoid bearing a single micropyle per oocyte with a funnel-shaped micropyle canal and vestibule covered with longitudinal folds, typical of the genus Brycon. The embryonic development of B. gouldingi was characterized by six stages with distinct features: zygote (from fertilization up to formation of egg-cell); cleavage (cell divisions resulting in blastomeres, including the morula phase); blastula (several embryonic cells in a cup shape, without distinction of cell boundaries); gastrula (cell movement); histogenesis/organogenesis (formation of tissues and organs); and hatching (larval chorion rupture). Right after hatching, the larvae presented neither swimming abilities nor visual accuracy, and the digestive trait was undifferentiated. The present study is the first report on biological features of embryogenesis in B. gouldingi, providing relevant information to several approaches, mainly related to taxonomy, ecology, conservation and captive rearing of this new Brycon species.

  7. A complex of species related to Paradiscogaster glebulae (Digenea: Faustulidae) in chaetodontid fishes (Teleostei: Perciformes) of the Great Barrier Reef.

    PubMed

    Diaz, Pablo E; Bray, Rodney A; Cutmore, Scott C; Ward, Selina; Cribb, Thomas H

    2015-10-01

    A total of 1523 individuals of 34 species of chaetodontids from the Great Barrier Reef were examined for faustulid trematodes. Specimens resembling Paradiscogaster glebulae Bray, Cribb & Barker, 1994 were found in nine chaetodontid species at three localities. These specimens are shown, on the basis of combined morphological and molecular analyses, to comprise a complex of morphologically similar and partly cryptic species. The complex may comprise as many as six distinct species of which three are resolved here. The true P. glebulae is identified in Chaetodon ornatissimus Cuvier, 1831, Chaetodon aureofasciatus Macleay, 1878, Chaetodon plebeius Cuvier, 1831, Chaetodon rainfordi McCulloch, 1923 and Chaetodon speculum Cuvier, 1831. Two new species are described, Paradiscogaster munozae n. sp. from Heniochus varius (Cuvier, 1829), Heniochus chrysostomus Cuvier, 1831 and Chaetodon citrinellus Cuvier, 1831 and Paradiscogaster melendezi n. sp. from Chaetodon kleinii Bloch, 1790. In terms of morphology the three species differ most clearly in the development of the appendages on the ventral sucker. The three species differ at 3-6consistent bp of ITS2 rDNA. The host-specificity of the three species differs strikingly. P. melendezi n. sp. infects just one fish species, P. glebulae infects species of only one clade of Chaetodon, and P. munozae n. sp. infects quite unrelated species. The basis of this unusual pattern of host-specificity requires further exploration. Two of the species recognised here, P. glebulae and P. munozae n. sp., showed apparent intra-individual variation in the ITS2 rDNA sequences as demonstrated by clear, replicated double peaks in the electropherograms.

  8. Complete Mitochondrial Reveals a New Phylogenetic Perspective on the Brackish Water Goby Mugilogobius Group (Teleostei: Gobiidae: Gobionellinae).

    PubMed

    Huang, Shih-Pin; Chen, I-Shiung; Jang-Liaw, Nian-Hong; Shao, Kwang-Tsao; Yung, Mana M N

    2016-10-01

    The Mugilogobius group consists of brackish water gobionellines widely distributed in the Indo-West Pacific region. Complete mitochondrial genome and morphological evidence was collected to estimate their phylogenetic relationship and taxonomic status. A total of 11 genera were sampled, including Brachygobius, Calamiana, Hemigobius, Mugilogobius, Pandaka, Pseudogobiopsis, Pseudogobius, Redigobius, Rhinogobius, Stigmatogobius, and Wuhanlinigobius, five of which were sequenced for the first time. A morphological phylogenetic tree was also reconstructed based on 35 characters. The molecular phylogenetic trees reveal that the Mugilogobius group contains four major clades. The present study also reveals that the adult male mouth size and forked sensory papillae row d can be considered as synapomorphies, and that the head pores on inter-orbital, anterior oculoscapular, and preopercular regions can be regarded as derived features among the Mugilogobius group. Furthermore, the absence of posterior oculoscapular pores may provide a clue for understanding the evolutionary history of the Mugilogobius group.

  9. †Kenyaichthyidae fam. nov. and †Kenyaichthys gen. nov. – First Record of a Fossil Aplocheiloid Killifish (Teleostei, Cyprinodontiformes)

    PubMed Central

    Altner, Melanie; Reichenbacher, Bettina

    2015-01-01

    The extant Cyprinodontiformes (killifishes) with their two suborders Cyprinodontoidei and Aplocheiloidei represent a diverse and well-studied group of fishes. However, their fossil record is comparatively sparse and has so far yielded members of the Cyprinodontoidei only. Here we report on cyprinodontiform fossils from the upper Miocene Lukeino Formation in the Tugen Hills of the Central Rift Valley of Kenya, which represent the first fossil record of an aplocheiloid killifish. A total of 169 specimens - mostly extraordinarily well preserved - and a sample of ten extant cyprinodontiform species were studied on the basis of morphometrics, meristics and osteology. A phylogenetic analysis using PAUP was also conducted for the fossils. Both the osteological data and the phylogenetic analysis provide strong evidence for the assignment of the fossils to the Aplocheiloidei, and justify the definition of the new family †Kenyaichthyidae, the new genus †Kenyaichthys and the new species †K. kipkechi sp. nov. The phylogenetic analysis unexpectedly places †Kenyaichthys gen. nov. in a sister relationship to the Rivulidae (a purely Neotropical group), a probable explanation might be lack of available synapomorphies for the Rivulidae, Nothobranchiidae and Aplocheilidae. The specimens of †K. kipkechi sp. nov. show several polymorphic characters and large overlap in meristic traits, which justifies their interpretation as a species flock in statu nascendi. Patterns of variation in neural and haemal spine dimensions in the caudal vertebrae of †Kenyaichthys gen. nov. and the extant species studied indicate that some previously suggested synapomorphies of the Cyprinodontoidei and Aplocheiloidei need to be revised. PMID:25923654

  10. The role of pelagic swarm fish (Myctophidae: Teleostei) in the oceanic life cycle of Anisakis sibling species at the Mid-Atlantic Ridge, Central Atlantic.

    PubMed

    Klimpel, Sven; Kellermanns, Esra; Palm, Harry W

    2008-12-01

    First information is provided on the parasitation and feeding ecology of the myctophid fish species Myctophum punctatum and Notoscopelus kroyeri from the Mid-Atlantic Ridge (MAR), Central Atlantic. Four different parasite species were found in both fish with a similar high prevalence and intensity of infestation. The digeneans Gonocerca phycidis and Lethadena sp. were isolated as adults from the stomach, larval tetraphyllidean cestodes (Scolex pleuronectis) from the intestine, and genetically identified larval anisakid nematodes of Anisakis simplex (s.s.) from the body cavity. No further Anisakis sibling species could be identified. Both myctophids had small pelagic crustaceans, mainly copepods and hyperiids, within their stomach contents. Ostracods, euphausiids, decapods, and amphipods were minor food components, demonstrating the pelagic environment for both fish. The recorded parasites including the anisakid A. simplex (s.s.) perform pelagic life cycles within the region, benefiting from extensive diurnal vertical migrations of their fish hosts. Comparison of the host range among the anisakis sibling species suggests that the A. simplex complex has low host specificity, infecting toothed and baleen whales on their extensive oceanic migrations. This contrasts the Anisakis physeteris complex that is restricted to toothed whales of the families Kogiidae and Physeteridae. Specificity in the teleost intermediate hosts for both complexes seems to be low, and sympatric occurrence of different siblings within the same intermediate hosts is likely. Myctophid swarm fish as important copepod feeders at the MAR significantly contribute to the oceanic anisakid nematode life cycle, especially considering the 100% prevalence and high intensity of infestation. Further genetic identification of Anisakis nematodes is needed in order to understand the sibling species distribution, along the MAR and within other oceanic environments.

  11. A new species of Comephoronema (Nematoda: Cystidicolidae) from the stomach of the abyssal halosaur Halosauropsis macrochir (Teleostei) from the Mid-Atlantic Ridge.

    PubMed

    Moravec, Frantisek; Klimpel, Sven

    2007-08-01

    A new species of parasitic nematode Comephoronema macrochiri n. sp. (Cystidicolidae), is described from the stomach of the marine deep-sea fish Halosauropsis macrochir (abyssal halosaur) from the Mid-Atlantic Ridge (MAR). The new species, studied with both light and scanning electron microscopy, is characterized mainly by 6 pairs of preanal papillae, by which it principally differs from members of Ascarophis; the spicules are 297-375 microm and 99-120 microm long and fully developed eggs possess 2 long filaments on 1 pole. Rhabdochona beatriceinsleyae is transferred to Comephoronema as C. beatriceinsleyae (Holloway and Klewer, 1969) n. comb. Comephoronema macrochiri differs from all other congeners mainly in having eggs with filaments on 1 pole only, and from individual species by some additional features such as the number of preanal papillae, the shape of pseudolabial projections, and the body and organ measurements.

  12. Next generation sequencing yields the complete mitochondrial genome of the Endangered Chilean silverside Basilichthys microlepidotus (Jenyns, 1841) (Teleostei, Atherinopsidae), validated with RNA-seq.

    PubMed

    Véliz, David; Vega-Retter, Caren; Quezada-Romegialli, Claudio

    2016-01-01

    The complete sequence of the mitochondrial genome for the Chilean silverside Basilichthys microlepidotus is reported for the first time. The entire mitochondrial genome was 16,544 bp in length (GenBank accession no. KM245937); gene composition and arrangement was conformed to that reported for most fishes and contained the typical structure of 2 rRNAs, 13 protein-coding genes, 22 tRNAs and a non-coding region. The assembled mitogenome was validated against sequences of COI and Control Region previously sequenced in our lab, functional genes from RNA-Seq data for the same species and the mitogenome of two other atherinopsid species available in Genbank.

  13. Ultrastructural Studies of Germ Cell Development and the Functions of Leydig Cells and Sertoli Cells associated with Spermatogenesis in Kareius bicoloratus (Teleostei, Pleuronectiformes, Pleuronectidae)

    PubMed Central

    Kang, Hee-Woong; Kim, Sung Hwan; Chung, Jae Seung

    2016-01-01

    The ultrastructures of germ cells and the functions of Leydig cells and Sertoli cells during spermatogenesis inmale Kareius bicoloratus (Pleuronectidae) were investigated by electron microscope observation. Each of the well-developed Leydig cells during active maturation division and before spermiation contained an ovoid vesicular nucleus, a number of smooth endoplasmic reticula, well-developed tubular or vesicular mitochondrial cristae, and several lipid droplets in the cytoplasm. It is assumed that Leydig cells are typical steroidogenic cells showing cytological characteristics associated with male steroidogenesis. No cyclic structural changes in the Leydig cells were observed through the year. However, although no clear evidence of steroidogenesis or of any transfer of nutrients from the Sertoli cells to spermatogenic cells was observed, cyclic structural changes in the Sertoli cells were observed over the year. During the period of undischarged germ cell degeneration after spermiation, the Sertoli cells evidenced a lysosomal system associated with phagocytic function in the seminiferous lobules. In this study, the Sertoli cells function in phagocytosis and the resorption of products originating from degenerating spermatids and spermatozoa after spermiation. The spermatozoon lacks an acrosome, as have been shown in all teleost fish spermatozoa. The flagellum or sperm tail of this species evidences the typical 9+2 array of microtubules. PMID:27294207

  14. Geographical differentiation of the Euchiloglanis fish complex (Teleostei: Siluriformes) in the Hengduan Mountain Region, China: Phylogeographic evidence of altered drainage patterns.

    PubMed

    Li, Yanping; Ludwig, Arne; Peng, Zuogang

    2017-02-01

    The uplift of the Tibetan Plateau caused significant ecogeographical changes that had a major impact on the exchange and isolation of regional fauna and flora. Furthermore, Pleistocene glacial oscillations were linked to temporal large-scale landmass and drainage system reconfigurations near the Hengduan Mountain Region and might have facilitated speciation and promoted biodiversity in southwestern China. However, strong biotic evidence supporting this role is lacking. Here, we use the Euchiloglanis fish species complex as a model to demonstrate the compound effects of the Tibetan Plateau uplift and Pleistocene glacial oscillations on species formation in this region. The genetic structure and geographical differentiation of the Euchiloglanis complex in four river systems within the Hengduan Mountain Region were deduced using the cytochrome b (cyt b) gene and 10 microsatellite loci from 360 to 192 individuals, respectively. The results indicated that the populations were divided into four independently evolving lineages, in which the populations from the Qingyi River and Jinsha River formed two sub-lineages. Phylogenetic relationships were structured by geographical isolation, especially near drainage systems. Divergence time estimation analyses showed that the Euchiloglanis complex diverged from its sister clade Pareuchiloglanis sinensis at around 1.3 Million years ago (Ma). Within the Euchiloglanis complex, the divergence time between the Dadu-Yalong and Jinsha-Qingyi River populations occurred at 1.0 Ma. This divergence time was in concordance with recent geological events, including the Kun-Huang Movement (1.2-0.6 Ma) and the lag time (<2.0 Ma) of river incision in the Hengduan Mountain Region. Population expansion signals were detected from mismatched distribution analyses, and the expansion times were concurrent with Pleistocene glacier fluctuations. Therefore, current phylogeographic patterns of the Euchiloglanis fish complex in the Hengduan Mountain Region were influenced by the uplift event of the Tibetan Plateau and were subsequently altered by paleo-river transitions during the late Pleistocene glacial oscillations.

  15. Delimiting species by reproductive isolation: the genetic structure of epigean and hypogean Trichomycterus spp. (Teleostei, Siluriformes) in the restricted area of Torotoro (Upper Amazon, Bolivia).

    PubMed

    Renno, Jean-François; Gazel, Claude; Miranda, Guido; Pouilly, Marc; Berrebi, Patrick

    2007-11-01

    Genetic variability of Trichomycterus from the region of Torotoro (Bolivia, Upper Amazon), distributed in the same watershed where the habitat is structured by waterfalls, canyons and a cave, was studied by allozyme (twelve putative loci) and RFLP-mtDNA (DLoop and cytochrome b) analyses. Alloenzymatic variation studied by Correspondence Analysis and Maximum Likelihood Analysis revealed a four-group structure, which was largely congruent with the distribution of the 14 mtDNA haplotypes. Two of these four clusters (I and II) were differentiated by two diagnostic loci (IDH and G3PDH), two semi-diagnostic loci (PGM and 6PGDH) and consequently a very high F(st )value (estimator theta = 0.77). Therefore, clusters I and II are reproductively isolated. The distribution limit of these two (sibling) species does not correspond to those of the morphological species of Trichomycterus identified in this region: the epigean T. cf. barbouri and the hypogean T. chaberti. However, hypogean fish exhibited two mtDNA haplotypes, a private one and another shared with the epigean Trichomycterus from upstream reaches.

  16. [Hyphessobrycon taphorni and H. eschwartzae (Teleostei: Characidae) two new species of fish in the basin of Madre de Dios river, Peru].

    PubMed

    Garcia-Alzate, Carlos A; Romin-Valencia, César; Ortega, Hernán

    2013-06-01

    Hyphessobrycon with 129 valid species, is a genus of fish that has a great diversity of species in the Neotropical ichthyofauna, reaches its greatest diversity in the Amazon basin with about 70% of these species, is highly desired by hobbyists because of their beauty and color, and are still meeting new species. We analyzed specimens from the Departamento de Ictiología, Museo de Historia Natural de la Universidad Mayor de San Marcos, Lima, Perú (MUSM); and measurements of the specimens were taken point to point with digital calipers. Observations of bone and cartilage structures were made on cleared and stained (C&S) samples. The morphometric relationships between species using 21 variables were explored using a principal component analysis (PCA). Here we describe two new species, Hyphessobrycon taphorni and H. eschwartzae from the Madre de Dios River drainage, Peru. Hyphessobrycon taphorni sp. n. can be distinguished by the number of dorsal-fin rays (iii, 8), by the number of: pored lateral-line scales (4-5), teeth in the outer premaxillary row (1-2), teeth in the inner premaxillary row (7-8), by: the caudal-peduncle length (11.4-16.4% SL), number of lateral scales (28-29, except from H. loretoensis which has 29-30) and absence of a humeral spot (vs. present), it differs from H. loretoensis by the number of: scales between the lateral line and the anal fin origin (4 vs. 3) and maxillary teeth (2 vs. 3-4), and it differs from H. agulha by the number of branched pectoral-fin rays (11-12 vs. 9-10). Hyphessobrycon eschwartzae sp. n. is distinguished by the number of: simple anal-fin rays (iv), teeth on the dentary (13-15), teeth in the inner premaxillary row (6), teeth in the outer premaxillary row (3, except from H. heterorhabdus and H. loretoensis which have 3-4); it differs from H. loretoensis by the number of: pored lateral-line scales (7 vs. 9-10), scales between the lateral line and the dorsal-fin origin (5 vs. 3-4); it differs from H. agulha in the number of lateral scales (30-31 vs. 33-34), by the number of: predorsal scales (9 vs. 10), maxillary teeth (4 vs. 0-1); in having in life a red lateral stripe above the dark lateral stripe that extends from the posterior part of the opercle to the caudal peduncle (vs. absent) and by the presence of bony hooks in mature males only on the anal fin (vs. hooks on all fins, including the caudal).

  17. Life-history traits of temperate and thermophilic barracudas (Teleostei: Sphyraenidae) in the context of sea warming in the Mediterranean Sea.

    PubMed

    Villegas-Hernández, H; Muñoz, M; Lloret, J

    2014-06-01

    This study indicated that the life-history traits of European barracuda Sphyraena sphyraena are apparently better suited to their environmental conditions compared to the more physically restricted life-history traits of the yellow-mouth barracuda Sphyraena viridensis, which co-habit the north-western Mediterranean Sea. The latter thermophilic species has a considerably higher reproductive potential as it invests its energy reserves in larger numbers of hydrated eggs per spawning batch. This would favour its population growth rates within the study area, especially if sea warming continues, in which case it is likely that the spawning phenology of this species would give it an advantage.

  18. Morphology, ultrastructure, genetics, and morphometrics of Diplostomum sp. (Digenea: Diplostomidae) metacercariae infecting the European flounder, Platichthys flesus (L.) (Teleostei: Pleuronectidae), off the northwest coast of Portugal.

    PubMed

    Cavaleiro, Francisca I; Pina, Susana; Russell-Pinto, Fernanda; Rodrigues, Pedro; Formigo, Nuno E; Gibson, David I; Santos, Maria J

    2012-01-01

    The morphology, ultrastructure, genetics, and morphometrics of a species of Diplostomum von Nordmann 1832 (Digenea: Diplostomidae), isolated from the European flounder (Platichthys flesus (L.)) caught off the northwest coast of Portugal, are characterized. The metacercarial stage was found unencysted in the lens capsule of the eye. Light microscopical observations revealed the existence of some variability in specimen shape and size, with two morphotypes, referred to as "round" and "long", being apparent. Scanning electron microscopy revealed a smooth, unarmed tegument, with the lappet region being the most irregular and porose. Both the oral and ventral suckers were provided with a series of papillae, which presented very distinctive ultrastructural features and were particularly conspicuous in the case of the ventral sucker. The two morphotypes detected were found to have 100% genetic correspondence in the 18S + ITS1 + 5.8S region of the rDNA. Since the genetic data for this metacercaria differed from those of the species of Diplostomum available in GenBank, a description of a new genotype (accession number GQ370809) is provided. The molecular phylogenetic analyses, in conjunction with principal components and cluster analyses based on morphometric data, revealed the existence of consistent differences between the Diplostomum sp. metacercariae from flounder compared with Diplostomum spathaceum, Diplostomum mergi, Diplostomum pseudospathaceum, and Diplostomum paracaudum. The latter of these species was found to be the most similar to the present material. Our results do not support an evolutionary separation of the European and North American species of Diplostomum.

  19. Expression of a low-molecular-weight (10 kDa) calcium binding protein in glial cells of the brain of the trout (Teleostei).

    PubMed

    Manso, M J; Becerra, M; Becerra, M; Anadón, R

    1997-11-01

    Calcium-binding proteins of the EF-hand family are widely distributed in the vertebrate central nervous system. In the present study of the trout brain, immunocytochemistry with a monoclonal antibody against chick gut calbindin-28k and a polyclonal antibody against bovine S100 protein specifically stained ependymocytes and radial glia cells with identical patterns. Western blot analysis of trout brain extracts with the antibodies to S100 and calbindin stained the same low-molecular-weight (10 kDa) protein band. In rat brain extracts, however, the monoclonal antibody to calbindin recognized a major protein band with molecular weight corresponding to that of calbindin-28k. This indicates that the trout protein is a new calcium-binding-like (calbindin-like) molecule that is immunologically related to both S100 and calbindin. Immunocytochemical studies of the trout brain using the antibodies to CaB and S100 showed that ependymocytes were stained in most ventricular regions, except in a few specialized ependymal areas of the ventral telencephalon, epithalamus, hypothalamus (including the paraventricular organ and saccus vasculosus) and brain stem. Immunocytochemistry also indicated the presence of calbindin-like protein in radial glia cells of several regions of the brain (thalamus, pretectal region, optic tectum, and rhombencephalon). Differences in immunoreactivity between neighbouring ependymal areas suggest that this protein may be a useful marker of different territories. All immunoreactive glial cells were nicotin-adenin-dinucleotide-phosphate diaphorase-positive, although this enzymohistochemical reaction is not specific for these glial cells since it reveals oligodendrocytes and some neurons. Immunoreactivity appears at different developmental stages in the different brain regions, with a broadly caudorostral gradient, suggesting that the expression of this protein is developmentally regulated. Comparison of the distribution of the calbindin-like protein with that of glial acidic fibrillary protein indicates that calbindin-like immunocytochemistry is a specific technique for revealing radial glia and ependymocytes in the trout.

  20. Developmental shifts in functional morphology of the retina in Atlantic tarpon, Megalops atlanticus (Elopomorpha: Teleostei) between four ecologically distinct life-history stages.

    PubMed

    Taylor, Scott M; Loew, Ellis R; Grace, Michael S

    2011-07-01

    The Atlantic tarpon, Megalops atlanticus, is a large piscivorous fish that supports economically important recreational fisheries in the Gulf of Mexico, Caribbean, and Florida Atlantic coast. Megalops atlanticus undergoes ontogenetic shifts in morphology, hatching in the open ocean as larvae (less than 1 cm in length), moving into hypoxic turbid mangrove marshes as juveniles (around 10 cm in length), and then moving into coastal oceanic waters as adults (over 100 cm in length). In this study, photoreceptor distributions, opsin distributions, and photoreceptor absorbance characteristics were studied with light microscopy, transmission electron microscopy, antiopsin immunofluorescence, and microspectrophotometry, respectively, at four ecologically distinct life-history stages--premetamorphic larva, settlement stage, juvenile, and adult. The purposes of this study were 1) to determine the extent to which the retina of M. atlanticus changes over the course of development and 2) to relate these retinal changes with ecological shifts between developmental stages. The new data presented here indicate that the M. atlanticus retina changes substantially in rod and cone distributions and absorbance characteristics over the course of development and that these changes correlate closely with those in habitat and behavior. We show that M. atlanticus has a rod-dominated retina at the larval stage (which is unusual for teleost larvae) and that the scotopic visual system becomes far better developed with maturity, adding a substantial tapetum and high densities of small, bundled, and stacked rod cells. We also show that there are shifts in cone and rod spectral sensitivities and an increase in the diversity of spectrally distinct cone classes, including the addition of ultraviolet cones as fish mature into adults.

  1. Comparison of the bioaccumulation from seawater and depuration of heavy metals and radionuclides in the spotted dogfish Scyliorhinus canicula (Chondrichthys) and the turbot Psetta maxima (Actinopterygii: Teleostei).

    PubMed

    Jeffree, Ross A; Warnau, Michel; Teyssié, Jean-Louis; Markich, Scott J

    2006-09-15

    The bioaccumulation of selected heavy metals and radionuclides ((241)Am, (109)Cd, (57)Co, (51)Cr, (134)Cs, (54)Mn and (65)Zn) from seawater was experimentally compared in the Chondrichthyan Scyliorhinus canicula (spotted dogfish) and the Actinopterygian Teleost Psetta maxima (turbot), of comparable size, age and benthic feeding habits. The speciation of these elements in seawater (salinity 38 per thousand, pH 8.1, temperature 16.5 degrees C) was also calculated to determine their potential bioavailability. The uptake rates, measured over 14 days, varied greatly among isotopes and between species. Concentration factors (CFs) in P. maxima varied 5-fold between ca. 0.2 for (51)Cr and 2.5 for (65)Zn and (134)Cs, whereas in S. canicula they varied by a much greater factor of 350, with CFs for (51)Cr and (241)Am ranging from ca. 0.4 to 140, respectively. With the exception of (134)Cs, all radiotracers were accumulated at a faster rate in S. canicula than in P. maxima, particularly for (241)Am and (65)Zn where the CFs attained during the uptake phase were, two and one order of magnitude greater in S. canicula, respectively. In contrast, (134)Cs reached a CF of about 2.5 in P. maxima, which was 5-fold greater than in S. canicula. Patterns of loss from the experimental depuration phase over 29 days showed greater similarities between species, compared to the uptake phase that highlighted the greater differences between elements. The distributions of these seven radioisotopes among six body components indicated that between the two species the skin of the dogfish displayed a greater bioaccumulation potential, particularly for (241)Am, (57)Co and (65)Zn. However (65)Zn was also distinctive from (241)Am and (57)Co in its pattern of bioaccumulation in dogfish, with its other body components attaining concentrations of (65)Zn that were comparable to the levels found in its skin. The heightened uptake of (134)Cs in turbot was characterised by a more even percentage distribution among its tissues compared to (241)Am and (57)Co, but every tissue of turbot had a higher concentration of (134)Cs, compared to dogfish, particularly the muscle and liver. The elevated uptake rates and higher CFs for most radioisotopes indicate that S. canicula is more susceptible than P. maxima to exposure and contamination by these metals and radionuclides in seawater. These experimentally-determined differences between dogfish and turbot in their bioaccumulation characteristics were assessed against a set of criteria erected to evaluate the working hypothesis that they were taxonomically based. The outcomes of this initial assessment were supportive of this hypothesis that warrants further investigation.

  2. Biodiversity of the Betta smaragdina (Teleostei: Perciformes) in the northeast region of Thailand as determined by mitochondrial COI and nuclear ITS1 gene sequences.

    PubMed

    Kowasupat, Chanon; Panijpan, Bhinyo; Laosinchai, Parames; Ruenwongsa, Pintip; Phongdara, Amornrat; Wanna, Warapond; Senapin, Saengchan; Phiwsaiya, Kornsunee

    2014-12-01

    In Thailand, there are currently five recognized species members of the bubble-nesting Betta genus, namely Betta splendens, B. smaragdina, B. imbellis, B. mahachaiensis and B. siamorientalis. In 2010, we indicated the possibility, based on COI barcoding evidence, that there might be two additional species, albeit cryptic, related to the type-locality B. smaragdina in some provinces in the northeast of Thailand. In the present study, after a more extensive survey of the northeast, and phylogenetic analyses based on COI and ITS1 sequences, the B. smaragdina group may be composed of at least 3 cryptic species members. The phylogenetic positions of these B. smaragdina group members in the bubble-nesting bettas' tree together with those of their congeners have been consolidated by better DNA sequence quality and phylogenetic analyses. With a better supported tree, the species statuses of B. siamorientalis and the Cambodian B. smaragdina-like fish, B. stiktos, are also confirmed.

  3. Biodiversity of the Betta smaragdina (Teleostei: Perciformes) in the northeast region of Thailand as determined by mitochondrial COI and nuclear ITS1 gene sequences☆

    PubMed Central

    Kowasupat, Chanon; Panijpan, Bhinyo; Laosinchai, Parames; Ruenwongsa, Pintip; Phongdara, Amornrat; Wanna, Warapond; Senapin, Saengchan; Phiwsaiya, Kornsunee

    2014-01-01

    In Thailand, there are currently five recognized species members of the bubble-nesting Betta genus, namely Betta splendens, B. smaragdina, B. imbellis, B. mahachaiensis and B. siamorientalis. In 2010, we indicated the possibility, based on COI barcoding evidence, that there might be two additional species, albeit cryptic, related to the type-locality B. smaragdina in some provinces in the northeast of Thailand. In the present study, after a more extensive survey of the northeast, and phylogenetic analyses based on COI and ITS1 sequences, the B. smaragdina group may be composed of at least 3 cryptic species members. The phylogenetic positions of these B. smaragdina group members in the bubble-nesting bettas' tree together with those of their congeners have been consolidated by better DNA sequence quality and phylogenetic analyses. With a better supported tree, the species statuses of B. siamorientalis and the Cambodian B. smaragdina-like fish, B. stiktos, are also confirmed. PMID:25606392

  4. Southeast Asian mouth-brooding Betta fighting fish (Teleostei: Perciformes) species and their phylogenetic relationships based on mitochondrial COI and nuclear ITS1 DNA sequences and analyses

    PubMed Central

    Panijpan, Bhinyo; Kowasupat, Chanon; Laosinchai, Parames; Ruenwongsa, Pintip; Phongdara, Amornrat; Senapin, Saengchan; Wanna, Warapond; Phiwsaiya, Kornsunee; Kühne, Jens; Fasquel, Frédéric

    2014-01-01

    Fighting fish species in the genus Betta are found in several Southeast Asian countries. Depending on the mode of paternal care for fertilized eggs and hatchlings, various species of the betta fish are classified as mouth brooders or nest builders whose members in turn have been grouped according to their similarities mainly in morphology. The mouth brooders as well as some nest builders involved in the present study include fishes discovered and identified subsequent to previous reports on species groupings and their positions on phylogenetic trees based on DNA sequences that differ from those used by us in this study. From the mitochondrial COI gene and nuclear ITS1 gene sequences and more accurate analyses we conclude that the following members of the mouth-brooding pairs, named differently previously, are virtually identical, viz the Betta prima–Betta pallida pair and Betta ferox–Betta apollon pair. The Betta simplex, hitherto believed to be one species, could possibly be genetically split into 2 distinct species. In addition, several other established type-locality fishes could harbor cryptic species as judged by genetic differences. Assignments of fish species to groups reported earlier may have to be altered somewhat by the present genetic findings. We propose here a new Betta fish phylogenetic tree which, albeit being similar to the previous ones, is clearly different from them. Our gene-based evidence also leads to assignments of some fishes to new species groups and alters the positions of some species on the new phylogenetic tree, thus implying different ancestral relationships. PMID:25606468

  5. Comparative evaluation of Na(+) uptake in Cyprinodon variegatus variegatus (Lacepede) and Cyprinodon variegatus hubbsi (Carr) (Cyprinodontiformes, Teleostei): Evaluation of NHE function in high and low Na(+) freshwater.

    PubMed

    Brix, Kevin V; Esbaugh, Andrew J; Mager, Edward M; Grosell, Martin

    2015-07-01

    The euryhaline pupfish, Cyprinodon variegatus variegatus (Cvv), can successfully osmoregulate in ≥2 mM Na(+) and a freshwater population (Cyprinodon variegatus hubbsi; Cvh) osmoregulates at ≥0.1mM Na(+). We previously demonstrated that Cvv relies on an apical NKCC and NHE in the gill for Na(+) uptake in high (7mM) and intermediate (2 mM) Na(+) concentrations, while Cvh relies only on NHE for Na(+) uptake. This study investigated whether differential NHE isoform use explains differences in Na(+) uptake kinetics between these two populations. We further studied whether Cvh uses a NHE-Rh metabolon or carbonic anhydrase (CA) to overcome thermodynamic challenges of NHE function in dilute freshwater. Transfer to more dilute freshwater resulted in upregulation of nhe-2 (Cvv only) and nhe-3 (Cvv and Cvh). Relative expression of nhe-3 compared to nhe-2 was 2-fold higher in Cvv, but 200-fold higher in Cvh suggesting that nhe-3 expression is an important freshwater adaptation for Cvh. Simultaneous measurement of Na(+) and Tamm flux under various conditions provided no support for a NHE-Rh metabolon in either population. Carbonic anhydrase activity in Cvv was comparable in 7 and 2 mM Na(+) acclimated fish. In Cvh, CA activity increased by 75% in 0.1 mM Na(+) acclimated fish compared to 7 mM Na(+) fish. Ethoxzolamide had variable effects, stimulating and reducing Na(+) uptake in Cvv acclimated to 7 and 2 mM Na(+), while reducing Na(+) uptake in 7 and 0.1mM Na(+) acclimated Cvh. This suggests that CA plays important, but different roles in regulating Na(+) uptake in Cvv and Cvh.

  6. A new deep-reef scorpionfish (Teleostei, Scorpaenidae, Scorpaenodes) from the southern Caribbean with comments on depth distributions and relationships of western Atlantic members of the genus

    PubMed Central

    Baldwin, Carole C.; Pitassy, Diane E.; Robertson, D. Ross

    2016-01-01

    Abstract A new species of scorpionfish, Scorpaenodes barrybrowni Pitassy & Baldwin, sp. n. which is described, was collected during submersible diving in the southern Caribbean as part of the Smithsonian’s Deep Reef Observation Project (DROP). It differs from the other two western Atlantic species of the genus, Scorpaenodes caribbaeus and Scorpaenodes tredecimspinosus, in various features, including its color pattern, having an incomplete lateral line comprising 8–10 pored scales, tending to be more elongate, usually having the 11th–12th pectoral-fin rays elongate, and by 20–23% divergence in the cytochrome c oxidase I (COI) DNA barcode sequences. It further differs from one or the other of those species in head spination and in numbers of soft dorsal-fin rays, pectoral-fin rays, and precaudal + caudal vertebrae. Inhabiting depths of 95–160 m, the new species is the deepest western Atlantic member of the genus (Scorpaenodes caribbaeus occurs at depths < 35 m and Scorpaenodes tredecimspinosus from 7 to 82 m). DNA barcode data do not rigorously resolve relationships among the ten species of the genus for which those data are available. PMID:27551226

  7. A new, mesophotic Coryphopterus goby (Teleostei, Gobiidae) from the southern Caribbean, with comments on relationships and depth distributions within the genus.

    PubMed

    Baldwin, Carole C; Robertson, D Ross

    2015-01-01

    A new species of western Atlantic Coryphopterus is described from mesophotic depths off Curaçao, southern Caribbean. Coryphopteruscurasub sp. n., is similar to Coryphopterusdicrus in, among other features, having two prominent pigment spots of roughly equal intensity on the pectoral-fin base, the pelvic fins fused to form a disk, and no pelvic frenum. The two species can be differentiated by body depth (shallower in Coryphopteruscurasub at origin of dorsal fin and caudal peduncle); differences in the pigmentation on the head, trunk, and basicaudal region; and usually by total number of rays (spinous plus soft) in the second dorsal fin (10-11, usually 11, in Coryphopteruscurasub, 10 in Coryphopterusdicrus). Coryphopteruscurasub differs from other Coryphopterus species that have a prominent pigment spot on the lower portion of the pectoral-fin base (Coryphopteruspunctipectophorus and Coryphopterusvenezuelae) in, among other features, lacking a pelvic frenum. Coryphopteruscurasub was collected between 70 and 80 m, the deepest depth range known for the genus. Collections of Coryphopterusvenezuelae at depths of 65-69 m extend the depth range of that species by approximately 50 m. Mitochondrial cytochrome c oxidase subunit I (COI) data corroborate the recognition of Coryphopteruscurasub as a distinct species but do not rigorously resolve its relationships within the genus. A revised key to the western Atlantic species of Coryphopterus is presented.

  8. A new Haptoclinus blenny (Teleostei, Labrisomidae) from deep reefs off Curaçao, southern Caribbean, with comments on relationships of the genus.

    PubMed

    Baldwin, Carole C; Robertson, D Ross

    2013-01-01

    A second species of the blenniiform genus Haptoclinus is described from deep reefs off Curaçao, southern Caribbean. Haptoclinus dropi sp. n. differs from the northwestern Caribbean Haptoclinus apectolophus Böhlke and Robins, 1974, in having 29 total dorsal-fin elements-III-I-XIII, 12 (vs. 31-III-I-XIV, 13 or III-I-XIII, 14); 19 anal-fin soft rays (vs. 20-21); 12 pectoral-fin rays (vs. 13); 12 precaudal vertebrae (vs. 13); and the first dorsal-fin spine longer than the second (vs. the second longer than the first). It further differs from Haptoclinus apectolophus in lacking scales (vs. three-quarters of body densely scaled), in having a distinctive pattern of spotting on the trunk and fins in preservative (vs. no spotting), and in lacking a fleshy flap on the anterior rim of the posterior nostril (vs. flap present). Color in life is unknown for Haptoclinus apectolophus, and the color description presented for the new species constitutes the first color information for the genus. Familial placement of Haptoclinus remains questionable, but the limited relevant information obtained from morphological examination of the new species provides additional support for a close relationship with the Chaenopsidae. Haptoclinus dropi represents one of numerous new teleost species emerging from sampling to 300 m off Curaçao as part of the Smithsonian Institution's Deep Reef Observation Project (DROP).

  9. A new deep-reef scorpionfish (Teleostei, Scorpaenidae, Scorpaenodes) from the southern Caribbean with comments on depth distributions and relationships of western Atlantic members of the genus.

    PubMed

    Baldwin, Carole C; Pitassy, Diane E; Robertson, D Ross

    2016-01-01

    A new species of scorpionfish, Scorpaenodes barrybrowni Pitassy & Baldwin, sp. n. which is described, was collected during submersible diving in the southern Caribbean as part of the Smithsonian's Deep Reef Observation Project (DROP). It differs from the other two western Atlantic species of the genus, Scorpaenodes caribbaeus and Scorpaenodes tredecimspinosus, in various features, including its color pattern, having an incomplete lateral line comprising 8-10 pored scales, tending to be more elongate, usually having the 11(th)-12(th) pectoral-fin rays elongate, and by 20-23% divergence in the cytochrome c oxidase I (COI) DNA barcode sequences. It further differs from one or the other of those species in head spination and in numbers of soft dorsal-fin rays, pectoral-fin rays, and precaudal + caudal vertebrae. Inhabiting depths of 95-160 m, the new species is the deepest western Atlantic member of the genus (Scorpaenodes caribbaeus occurs at depths < 35 m and Scorpaenodes tredecimspinosus from 7 to 82 m). DNA barcode data do not rigorously resolve relationships among the ten species of the genus for which those data are available.

  10. Phylogeography of Pteronotropis signipinnis, P. euryzonus, and the P. hypselopterus Complex (Teleostei: Cypriniformes), with Comments on Diversity and History of the Gulf and Atlantic Coastal Streams

    PubMed Central

    Mayden, Richard L.; Allen, Jason

    2015-01-01

    The cyprinid genus Pteronotropis is endemic to southeastern Gulf of Mexico and Atlantic Ocean of North America. Never before has the genus been demonstrated to be monophyletic. We investigate both the phylogenetic relationships and the phylogeography of some species in the genus using mitochondrial ND2 sequences. In no analysis is the genus resolved as monophyletic if Notropis harperi is not included in the genus. Biogeographic and phylogeographic evaluations are conducted with Pteronotropis, including P. signipinnis, P. euryzonus, and the P. hypselopterus complex. Patterns of relationships and population genetic analyses support divergences within multiple clades both at the species level and within species that are tied to abiotic changes in the region. Replicated patterns across clades are observed, as well as patterns previously found in other taxa. Pteronotropis hypselopterus is likely not a natural grouping as populations from some drainages form clades more closely related to other species of the genus. The general patterns of relationships indicate likely cryptic species not currently recognized. Finally, the patterns of species relationships and clades and population structuring within species serve as another example of replicated divergences in the biodiversity east and west of the Mobile Bay. PMID:26114110

  11. Use of dynamic occupancy models to assess the response of Darters (Teleostei: Percidae) to varying hydrothermal conditions in a southeastern United States tailwater

    USGS Publications Warehouse

    Shea, C.P.; Bettoli, Phillip William; Potoka, K. M.; Saylor, C. F.; Shute, P. W.

    2015-01-01

    During the past 100 years, most large rivers in North America have been altered for flood control, hydropower, navigation or water supply development. Although these activities clearly provide important human services, their associated environmental disturbances can profoundly affect stream-dwelling organisms. We used dynamic multi-species occupancy models combined with a trait-based approach to estimate the influence of site-level and species-level characteristics on patch dynamic rates for 15 darter species native to the Elk River, a large, flow-regulated Tennessee River tributary in Tennessee and Alabama. Dynamic occupancy modelling results indicated that for every 2.5 °C increase in stream temperature, darters were 3.94 times more likely to colonize previously unoccupied stream reaches. Additionally, large-bodied darter species were 3.72 times more likely to colonize stream reaches compared with small-bodied species, but crevice-spawning darter species were 5.24 times less likely to colonize previously unoccupied stream reaches. In contrast, darters were 2.21 times less likely to become locally extinct for every 2.5 °C increase in stream temperature, but high stream discharge conditions elevated the risk of local extinction. Lastly, the presence of populations in neighbouring upstream study reaches contributed to a lower risk of extinction, whereas the presence of populations in neighbouring downstream study reaches contributed to higher rates of colonization. Our study demonstrates the application of a trait-based approach combined with a metapopulation framework to assess the patch dynamics of darters in a regulated river. Results from our study will provide a baseline for evaluating the ecological consequences of alternative dam operations.

  12. Evaluating the resolution power of new microsatellites for species identification and stock delimitation in the Cape hakes Merluccius paradoxus and Merluccius capensis (Teleostei: Merlucciidae).

    PubMed

    Hoareau, T B; Klopper, A W; Dos Santos, S M R; Oosthuizen, C J; Bloomer, P

    2015-05-01

    The utility of 15 new and 17 previously published microsatellite markers was evaluated for species identification and stock delimitation in the deep-water hake Merluccius paradoxus and the shallow-water hake Merluccius capensis. A total of 14 microsatellites were polymorphic in M. paradoxus and 10 in M. capensis. Two markers could individually discriminate the species using Bayesian clustering methods and a statistical power analysis showed that the set of markers for each species is likely to detect subtle genetic differentiation (FST < 0·006) that will be valuable to delimit and characterize genetic stocks.

  13. Morphometric and molecular characterisation of specimens of Lepidapedon Stafford, 1904 (Digenea: Lepidapedidae) from the deep-sea fish Mora moro (Risso) (Teleostei: Moridae) in the western Mediterranean.

    PubMed

    Dallarés, Sara; Georgieva, Simona; Kostadinova, Aneta; Carrassón, Maite; Gibson, David I; Pérez-del-Olmo, Ana

    2013-07-01

    In a study of the parasites of the deep-sea fish Mora moro (Risso) (Gadiformes: Moridae) off the Mediterranean coasts of Catalonia and the Balearic Islands (Spain), we were able to distinguish two morphs of specimens belonging to Lepidapedon Stafford, 1904 (Digenea: Lepidapedidae). This material is herein described and illustrated. Comparative sequence analyses using partial mitochondrial nad1 sequences revealed that the material assigned to one of these morphs can be considered conspecific with the material identified as Lepidapedon desclersae Bray & Gibson, 1995 from the same host. However, the published nad1 sequence for L. desclersae was generated from a specimen ex M. moro from the North East Atlantic. Examination of the voucher specimens associated with this sequence revealed that both the North East Atlantic and the Mediterranean specimens ex M. moro differ from L. desclersae as described from its type-host, Lepidion eques (Günther), in the anterior extent of the vitelline fields which is further posterior, reaching only to the posterior margin of the external seminal vesicle in L. desclersae, versus being at the mid-level of this organ and reaching the posterior margin of the ventral sucker. Therefore, we have tentatively assigned the material characterised here, both morphologically and molecularly as Lepidapedon sp. Acquisition of additional sequences for both nad1 mitochondrial and 28S rRNA genes of L. desclersae from material ex Lepidion spp. is required in order to determine whether the observed morphometric variation reflects host-related or inter-specific differences. The second morph of Lepidapedon from M. moro is described and distinguished on morphometric grounds, such as the position of the most anterior vitelline follicles, which reach to the anterior margin of the ventral sucker. Its identity is commented upon, but, in view of the fact that there were few specimens and no molecular data available, it is not named.

  14. Description of karyotype in Hypostomus regani (Ihering, 1905) (Teleostei, oricariidae) from the Piumhi river in Brazil with comments on karyotype variation found in Hypostomus

    PubMed Central

    Mendes-Neto, Ernani de Oliveira; Vicari, Marcelo Ricardo; Artoni, Roberto Ferreira; Moreira-Filho, Orlando

    2011-01-01

    Abstract The paper represents a comparative cytogenetic analysis of three populations of Hypostomus regani in Brazil.Two populations belong to the Upper Paraná River Basin and the third one, the karyotype of which is described for the first time, was probably introduced into the São Francisco River Basin through transposition from the Piumhi River. Karyotype features of populations of Hypostomus regani from the Piracicaba and Tietê River Basins are also discussed. The occurrence of Hypostomus regani in the São Francisco River Basin is reported for the first time here. The study also revealed distinct differences in the location of the Ag-NORs between the analyzed populations that enable individuals from the Piumhi River, Mogi-Guaçu River and Tietê River to be distinguished from one another. Thus, the data obtained indicate the possibility of geographic variation fixing different karyotypes even in the same basin of origin. PMID:24260625

  15. A new species of Ituglanis from the Rio Xingu Basin, Brazil, and the evolution of pelvic fin loss in trichomycterid catfishes (Teleostei: Siluriformes: Trichomycteridae).

    PubMed

    Datovo, Aléssio

    2014-04-22

    A new species of the trichomycterid catfish genus Ituglanis is described from the Rio Curuá, Rio Xingu basin, Rio Amazonas drainage, Brazil. Ituglanis apteryx, new species, is promptly distinguished from congeners, except some specimens of I. parahybae (Eigenmann), by the absence of pelvic fins, girdle, and muscles. The new species differs from I. parahybae in the pattern of the cephalic laterosensory system; the absence of a posterior cranial fontanel; the presence of an epural; and the number of branchiostegal rays, ribs, and vertebrae. Ituglanis apteryx is one among the several trichomycterids lacking pelvic fins. Analysis reveals that pelvic fin loss independently evolved several times during the trichomycterid radiation.

  16. Revised diagnosis of the genus Gonorhynchus McClelland (Teleostei: Cyprinidae: Labeonini) with redescription of G. latius (Hamilton) and revalidation of G. wattanah (Sykes).

    PubMed

    Ciccotto, Patrick J; Page, Lawrence M

    2016-06-24

    A new diagnosis of the genus Gonorhynchus McClelland 1838 from South Asia is proposed. Seven species are contained in the genus: G. latius (Hamilton 1822), G. diplochilus (Heckel 1838), G. wattanah (Sykes 1839), G. macmahoni (Zugmayer 1912), G. burmanicus (Hora 1936), G. bicornis (Wu 1977), and G. periyarensis (Menon & Jacob 1996). Gonorhynchus latius, a senior synonym of the type species G. brevis M'Clelland 1839 is redescribed. Crossocheilus gohama (M'Clelland 1839) and Crossochilus rostratus Günther 1868 are considered junior synonyms of G. latius, and a neotype is designated for G. latius. Gonorhynchus wattanah (Sykes 1839) from the Krishna and Godavari River basins in western India is revalidated and redescribed with the designation of a neotype. Akrokolioplax Zhang & Kottelat 2006 is a junior synonym of Gonorhynchus.

  17. Morphology of the jaw, suspensorial, and opercle musculature of Beloniformes and related species (Teleostei: Acanthopterygii), with a special reference to the m. adductor mandibulae complex.

    PubMed

    Werneburg, Ingmar

    2015-01-01

    The taxon Beloniformes represents a heterogeneous group of teleost fishes that show an extraordinary diversity of jaw morphology. I present new anatomical descriptions of the jaw musculature in six selected beloniforms and four closely related species. A reduction of the external jaw adductor (A1) and a changed morphology of the intramandibular musculature were found in many Beloniformes. This might be correlated with the progressively reduced mobility of the upper and lower jaw bones. The needlefishes and sauries, which are characterised by extremely elongated and stiffened jaws, show several derived characters, which in combination enable the capture of fish at high velocity. The ricefishes are characterised by several derived and many plesiomorphic characters that make broad scale comparisons difficult. Soft tissue characters are highly diverse among hemiramphids and flying fishes reflecting the uncertainty about their phylogenetic position and interrelationship. The morphological findings presented herein may help to interpret future phylogenetic analyses using cranial musculature in Beloniformes.

  18. Modifications of the falciform process in the eye of beloniformes (Teleostei: Atherinomorpha): evolution of a curtain-like septum in the eye.

    PubMed

    Reckel, Frank; Melzer, Roland R

    2004-04-01

    In order to comparatively analyze curtain-like septa in the eyes of visually orientated "close-to-surface-predators" among atherinomorph teleosts, we examined the eyes of 24 atherinomorph species under a binocular microscope with regard to the falciform process and related structures in the vitreous cavity. Additionally, falciform process samples were analyzed by transmission electron microscopy. All the studied representatives of the Cyprinodontiformes and Atheriniformes, and of one of the beloniform suborder, Adrianichthyioidei, possess a "typical" processus falciformis. In the eyes of the representatives of the other beloniform suborder, Belonoidei, however, pigmented structures that originate in the region of the optic disc and protrude into the vitreous cavity were noted. In the Hemiramphidae (halfbeaks) and Exocoetidae (flying fishes) these pigmented structures have a more cone-like shape, whereas in the Belonidae (needlefishes) and Scomberesocidae (sauries) horizontally oriented heavily pigmented curtain-like septa occur that divide the vitreous cavity dorsoventrally. It is suggested that the "typical" processus falciformis represents a plesiomorphic feature within the Atherinomorpha, whereas the pigmented modifications of the falciform process must be seen as a synapomorphic character state of the Belonoidei. The curtain-like septum of the Belonidae and Scomberesocidae might have evolved from the cone-like structures that are found in the Exocoetoidea. The functional significance of the pigmented structures in the eye is as yet not clear, except for the curtain-like septum found in Belonidae. It might play a role in visual orientation near the water surface at Snell's window.

  19. Repeatability of clades as a criterion of reliability: a case study for molecular phylogeny of Acanthomorpha (Teleostei) with larger number of taxa.

    PubMed

    Chen, Wei-Jen; Bonillo, Céline; Lecointre, Guillaume

    2003-02-01

    Although much progress has been made recently in teleostean phylogeny, relationships among the main lineages of the higher teleosts (Acanthomorpha), containing more than 60% of all fish species, remain poorly defined. This study represents the most extensive taxonomic sampling effort to date to collect new molecular characters for phylogenetic analysis of acanthomorph fishes. We compiled and analyzed three independent data sets, including: (i) mitochondrial ribosomal fragments from 12S and 16s (814bp for 97 taxa); (ii) nuclear ribosomal 28S sequences (847bp for 74 taxa); and (iii) a nuclear protein-coding gene, rhodopsin (759bp for 86 taxa). Detailed analyses were conducted on each data set separately and the principle of taxonomic congruence without consensus trees was used to assess confidence in the results as follows. Repeatability of clades from separate analyses was considered the primary criterion to establish reliability, rather than bootstrap proportions from a single combined (total evidence) data matrix. The new and reliable clades emerging from this study of the acanthomorph radiation were: Gadiformes (cods) with Zeioids (dories); Beloniformes (needlefishes) with Atheriniformes (silversides); blenioids (blennies) with Gobiesocoidei (clingfishes); Channoidei (snakeheads) with Anabantoidei (climbing gouramies); Mastacembeloidei (spiny eels) with Synbranchioidei (swamp-eels); the last two pairs of taxa grouping together, Syngnathoidei (aulostomids, macroramphosids) with Dactylopteridae (flying gurnards); Scombroidei (mackerels) plus Stromatoidei plus Chiasmodontidae; Ammodytidae (sand lances) with Cheimarrhichthyidae (torrentfish); Zoarcoidei (eelpouts) with Cottoidei; Percidae (perches) with Notothenioidei (Antarctic fishes); and a clade grouping Carangidae (jacks), Echeneidae (remoras), Sphyraenidae (barracudas), Menidae (moonfish), Polynemidae (threadfins), Centropomidae (snooks), and Pleuronectiformes (flatfishes).

  20. Genetic divergence and phylogenetic relationships in grey mullets (Teleostei: Mugilidae) based on PCR-RFLP analysis of mtDNA segments.

    PubMed

    Papasotiropoulos, V; Klossa-Kilia, E; Kilias, G; Alahiotis, S

    2002-04-01

    The genetic differentiation and phylogenetic relationships among five species of the Mugilidae family (Mugil cephalus, Chelon labrosus, Liza aurata, Liza ramada, and Liza saliens) were investigated at the mtDNA level, on samples taken from Messolongi lagoon-Greece. RFLP analysis of three PCR-amplified mtDNA gene segments (12s rRNA, 16s rRNA, and CO I) was used. Ten, eight, and nine restriction enzymes were found to have at least one recognition site at 12s rRNA, 16s rRNA, and CO I genes, respectively. Several fragment patterns were revealed to be species-specific, and thus they could be useful in species taxonomy as diagnostic markers, as well as for further evolutionary studies. Seven different haplotypes were detected. The greatest amount of genetic differentiation was observed at the interspecific level, while little variation was revealed at the intraspecific level. The highest values of nucleotide sequence divergence were observed between M. cephalus and all the other species, while the lowest was found between C. labrosus and L. saliens. Dendrograms obtained by the three different methods (UPGMA, Neighbor-Joining, and Dollo parsimony), were found to exhibit in all cases the same topology. According to this, the most distinct species is M. cephalus, while the other species are clustered in two separate groups, thefirst one containing L. aurata and L. ramada, the other L. saliens and C. labrosus. This last clustering makes the monophyletic origin of the genus Liza questionable.

  1. The translocated Liza haematocheila (Teleostei: Mugilidae) as a new host of four species of Saturnius Manter, 1969 (Digenea: Hemiuridae) within its invasive range in the Black Sea.

    PubMed

    Pankov, Plamen; Gibson, David I; Kostadinova, Aneta

    2009-09-01

    This paper presents the first documented record of four species of Saturnius Manter, 1969 in Liza haematocheila (Temminck & Schlegel) in its invasive Pontic range. S. papernai Overstreet, 1977, S. dimitrovi Blasco-Costa, Pankov, Gibson, Balbuena, Raga, Sarabeev & Kostadinova, 2006, S. minutus Blasco-Costa, Pankov, Gibson, Balbuena, Raga, Sarabeev & Kostadinova, 2006 and Saturnius sp. are described and compared with existing data by means of multivariate morphometric analysis. The morphological and morphometric similarities between the specimens of Saturnius sp. from L. haematocheila and a small form of S. papernai from L. aurata indicate the possible existence of another, cryptic species. Although having acquired at least three species of Saturnius since its establishment in the Black Sea region, there is no evidence that a Pacific congener has been introduced with this fish. This is the first report of S. minutus from the Black Sea.

  2. Three species of Heteromazocraes Mamaev, 1981 (Monogenea: Mazocraeidae), including two new species from Thryssa spp. (Teleostei: Engraulidae) off Visakhapatnam coast, Bay of Bengal.

    PubMed

    Sailaja, Bade; Shameem, Ummey; Madhavi, Rokkam

    2017-03-01

    Three species of Heteromazocraes Mamaev, 1981 including two new taxa are described from the gills of three species of engraulid fishes Thryssa mystax (Bloch & Schneider), T. setirostris (Broussonet) and T. malabarica (Bloch) collected from the coastal waters off Visakhapatnam, Bay of Bengal. Heteromazocraes thryssaensis n. sp. differs from the closely related H. dodecacantha Mamaev, 1981 in the shape of the body and ovary, the number of testes and the number and shape of the genital hooks. Heteromazocraes engrauliae n. sp. differs from all the other species of the genus in the relative sizes of the haptoral clamps, in that the four closed clamps on the left side are larger than the two open clamps on the right side, in contrast to the situation in other species where the two open clamps on the anterior right side are markedly larger than the remaining clamps. Heteromazocraes kazikodiensis (Gupta & Khullar, 1967) Mamaev, 1981 regarded as a species inquirenda is redescribed with additional details and is reinstated as a valid species. A review of Heteromazocraes including a key for identification of the species is provided.

  3. Two deep evolutionary lineages in the circumtropical glasseye Heteropriacanthus cruentatus (Teleostei, Priacanthidae) with admixture in the south-western Indian Ocean.

    PubMed

    Gaither, M R; Bernal, M A; Fernandez-Silva, I; Mwale, M; Jones, S A; Rocha, C; Rocha, L A

    2015-09-01

    A phylogeographic study of the circumtropical glasseye Heteropriacanthus cruentatus was conducted. Molecular analyses indicate two mitochondrial cytochrome c oxidase subunit I (coI) lineages that are 10·4% divergent: one in the western Atlantic (Caribbean) and another that was detected across the Indo-Pacific. A fixed single nucleotide polymorphism (SNP) was detected at a nuclear locus (S7 ribosomal protein) and is consistent with this finding. There is evidence of recent dispersal from the Atlantic to the Indian Ocean with individuals of mixed lineages detected in South Africa and the Mozambique Channel. Using coalescent analyses of the mitochondrial dataset, time of divergence between lineages was estimated to be c. 15·3 million years. The deep divergence between these two lineages indicates distinct evolutionary units, however, due to the lack of morphological differences and evidence of hybridization between lineages, taxonomic revision is not suggested at this time.

  4. Changes along the male reproductive axis in response to social context in a gonochoristic gobiid, Zosterisessor ophiocephalus (Teleostei, Gobiidae), with alternative mating tactics.

    PubMed

    Scaggiante, Marta; Grober, Matthew S; Lorenzi, Varenka; Rasotto, Maria B

    2004-12-01

    Sexual selection has given rise, in several taxa, to intrasexual variation in male phenotype. While evolutionary studies have provided explanations of the adaptive function of this dramatic male phenotypic diversity, the proximate control of its expression has still to be completely understood. Several observations, primarily from sex-changing species, indicated a major role of social interactions in reproductive axis regulation and consequently in the expression of alternative male phenotypes. Here we documented changes along the male reproductive axis in response to social context in a gonochoristic species, the grass goby Zosterisessor ophiocephalus, where fully functional alternative male mating tactics appear to be expressed as an ontogenetic gradient. In the grass goby, larger and older males dig a nest and perform parental care, while smaller males sneak fertilization during territorial male spawning. Territorial males are characterized by a higher number of gonadotropin-releasing hormone (GnRH) neurons in forebrain preoptic area, smaller testes, larger seminal vesicles, and viscous ejaculates that last longer and contain fewer sperm than those of sneakers. To experimentally investigate the role of social factors in inducing changes along the male reproductive axis, sneakers were tested in two different situations: nesting alone or with ripe females. Sneakers that mated and performed parental care showed dramatic changes in brain, reproductive apparatus morphology, and ejaculate traits. GnRH-immunoreactive cells in forebrain preoptic area increased in number, reaching values typical of wild-caught parental males. Testes size decreased while seminal vesicle size increased and ejaculates showed lower sperm densities. These results were discussed within the framework of the social transduction hypothesis, which predicts that social experience should mediate, through a cascade of internal processes, shifts between morphs throughout life.

  5. Pretectum and accessory optic system in the filefish Navodon modestus (Balistidae, Teleostei) with special reference to visual projections to the cerebellum and oculomotor nuclei.

    PubMed

    Uchiyama, H; Matsutani, S; Ito, H

    1988-01-01

    The fiber connections of the accessory optic system (AOS) were investigated in a balistid fish, Navodon modestus (filefish), by means of horseradish peroxidase (HRP) and degeneration methods. Following injections of HRP into the corpus cerebelli, neurons in two retinal recipient nuclei, the area pretectalis pars dorsalis (APd) and area pretectalis pars ventralis (APv), were labeled retrogradely. In addition, a few neurons near the nucleus of the accessory optic tract (nAOT) were labeled. These neurons have dendrites extending into nAOT. Neurons in APv were also labeled by HRP injections into the oculomotor complex (nIII). However, no neurons were labeled in APd or nAOT. A few neurons in the lateral part of APv were labeled by HRP injections into the abducens nucleus (nVI). Three nuclei of the AOS, APd, APv and nAOT, were shown to receive tectal projections by the Fink-Heimer method. Thus, APv receives retinal and tectal projections, and in turn projects to corpus cerebelli, nIII and nVI. Specific efferent connections of the AOS in teleosts are discussed from phylogenetic aspects.

  6. First insights into the diversity of gill monogeneans of ‘Gnathochromis’ and Limnochromis (Teleostei, Cichlidae) in Burundi: do the parasites mirror host ecology and phylogenetic history?

    PubMed Central

    Gelnar, Milan; Koblmüller, Stephan; Vanhove, Maarten P.M.

    2016-01-01

    Monogenea is one of the most species-rich groups of parasitic flatworms worldwide, with many species described only recently, which is particularly true for African monogeneans. For example, Cichlidogyrus, a genus mostly occurring on African cichlids, comprises more than 100 nominal species. Twenty-two of these have been described from Lake Tanganyika, a famous biodiversity hotspot in which many vertebrate and invertebrate taxa, including monogeneans, underwent unique and spectacular radiations. Given their often high degrees of host specificity, parasitic monogeneans were also used as a potential tool to uncover host species relationships. This study presents the first investigation of the monogenean fauna occurring on the gills of endemic ‘Gnathochromis’ species along the Burundese coastline of Lake Tanganyika. We test whether their monogenean fauna reflects the different phylogenetic position and ecological niche of ‘Gnathochromis’ pfefferi and Gnathochromis permaxillaris. Worms collected from specimens of Limnochromis auritus, a cichlid belonging to the same cichlid tribe as G. permaxillaris, were used for comparison. Morphological as well as genetic characterisation was used for parasite identification. In total, all 73 Cichlidogyrus individuals collected from ‘G.’ pfefferi were identified as C. irenae. This is the only representative of Cichlidogyrus previously described from ‘G.’ pfefferi, its type host. Gnathochromis permaxillaris is infected by a species of Cichlidogyrus morphologically very similar to C. gillardinae. The monogenean species collected from L. auritus is considered as new for science, but sample size was insufficient for a formal description. Our results confirm previous suggestions that ‘G.’ pfefferi as a good disperser is infected by a single monogenean species across the entire Lake Tanganyika. Although G. permaxillaris and L. auritus are placed in the same tribe, Cichlidogyrus sp. occurring on G. permaxillaris is morphologically more similar to C. irenae from ‘G.’ pfefferi, than to the Cichlidogyrus species found on L. auritus. Various evolutionary processes, such as host-switching or duplication events, might underlie the pattern observed in this particular parasite-host system. Additional samples for the Cichlidogyrus species occuring on G. permaxillaris and L. auritus are needed to unravel their evolutionary history by means of (co-)phylogenetic analyses. PMID:26855869

  7. Variation in thermal tolerance and routine metabolism among spring- and stream-dwelling freshwater sculpins (Teleostei: Cottidae) of the southeastern United States

    USGS Publications Warehouse

    Walsh, S.J.; Haney, D.C.; Timmerman, C.M.

    1997-01-01

    Evolutionary theory predicts that some aquatic organisms may adapt by directional selection to limiting physical environmental conditions, yet empirical data are conflicting. We sought to test the assumption that sculpins (family Cottidae) inhabiting thermally stable springs of the southeastern United States differ in temperature tolerance and metabolism from populations inhabiting more thermally labile stream habitats. Spring populations of pygmy sculpins (Coitus pygmaeus) and Ozark sculpins (C. hypselurus) differed interspecifically in thermal tolerance from populations of stream-dwelling mottled (C. bairdi) and Tallapoosa sculpins (C. tallapoosae), and both stream and spring populations of banded sculpins (C. carolinae). No intra- or interspecific differences in thermal tolerance were found among populations of C. bairdi, C. tallapoosae, or C. carolinae. Coitus pygmaeus acclimated to 15??C differed intraspecifically in routine metabolism from fish acclimated to 20?? and 25??C. Cottus pygmaeus and stream-dwelling C. bairdi and C. carolinae acclimated to temperatures of 20?? and 25??C showed no interspecific differences in routine metabolism. Our results suggest that some spring-adapted populations or species may be more stenothermal than stream-dwelling congeners, but a greater understanding of the interactions of other physical and biological factors is required to better explain micro- and macrohabitat distributions of eastern North American sculpins.

  8. Recovering cryptic diversity and ancient drainage patterns in eastern North America: historical biogeography of the Notropis rubellus species group (Teleostei: Cypriniformes).

    PubMed

    Berendzen, Peter B; Simons, Andrew M; Wood, Robert M; Dowling, Thomas E; Secor, Carol L

    2008-02-01

    The Central Highlands of North America contain a strikingly diverse assemblage of temperate freshwater fishes and have long been a focus of biogeographic studies. The rosyface shiner complex, Notropis rubellus and related species, is a member of this fauna exhibiting a disjunct highlands distribution occurring in the unglaciated regions of the Central Highlands and glaciated regions of the Central Lowlands. Until recently, N. rubellus was considered a single, widespread species exhibiting geographic variation in morphological characters. However, several studies have revealed that N. rubellus is a multi-species complex with closely related species endemic to drainages within each highland region. We examined genetic variation of the N. rubellus complex using a complete mtDNA cytochrome b gene sequence data set and combined mtDNA and published allozyme data sets. Parsimony and Bayesian analyses of the mitochondrial data set and parsimony analyses of a combined mitochondrial and allozyme data sets were largely consistent. Results of these analyses revealed ancient cryptic diversity within the N. rubellus complex that existed prior to the onset of Pleistocene glaciations. We identified seven strongly supported clades within the N. rubellus complex. Four clades are diagnosed as separate species (N. percobromus, N. rubellus, N. micropteryx and N. suttkusi) and three clades may represent undescribed forms. Relationships among these groups and their biogeographical patterns provided significant inferences on ichthyofaunal distributions in southeastern North America. These include the timing of the origin of the diversity, ancient drainage patterns and barriers to dispersal in the Central Highlands. The observation of increased diversity in N. rubellus suggests there may be greater diversity within other taxa with a similar distribution.

  9. Predator-prey interactions between Synbranchus marmoratus (Teleostei: Synbranchidae) and Hypsiboas pulchellus tadpoles (Amphibia: Hylidae): importance of lateral line in nocturnal predation and effects of fenitrothion exposure.

    PubMed

    Junges, Celina M; Lajmanovich, Rafael C; Peltzer, Paola M; Attademo, Andres M; Bassó, Agustín

    2010-11-01

    Environmental contaminants can disrupt interactions between aquatic species by altering community structure. We explored predator-prey interactions between marbled swamp juvenile eels (Synbranchus marmoratus; predator) and anuran tadpoles (Hypsiboas pulchellus; prey) in relation to two aspects: the importance of lateral line in the predator and whether the absence of light modifies predation rates; and the effect of a sub-lethal concentration of fenitrothion on both predator and prey. Eels were tested under two sensory conditions (lateral line intact and lateral line blocked by cobalt chloride) in dark conditions. Predation rates were evaluated using different treatments that combined predator and prey exposed or not to insecticide. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities were also measured in muscle samples of eels and tadpoles to explore whether fenitrothion affects predator and prey differentially. Marbled swamp eels were more efficient in feeding on tadpoles during the night than during the day, showing that lateral line makes an important contribution to prey detection and capture. Regarding pesticide effects, short-term (6 h) exposure to an ecologically relevant fenitrothion dose of 2.5 mg L(-1) altered the predator-prey relationship by changing prey behaviour, reducing prey detection and therefore increasing tadpole survival. At this concentration, the outcome of the predator-prey relationship appears biased in favor of the exposed tadpoles, which were released from predation risk, despite their altered behaviour and the higher inhibition percentages of tail BChE (70%) and AChE (51%) than in control individuals. Our study involving these model species and agrochemicals demonstrates that fenitrothion affected the outcome of a predator-prey relationship. Further studies are needed, in these species and other native amphibians, to investigate the nature of the mechanisms responsible for the adverse effects of pesticides on antipredator behaviour and predation efficiency.

  10. Phylogenetic analysis of molecular and morphological data highlights uncertainty in the relationships of fossil and living species of Elopomorpha (Actinopterygii: Teleostei).

    PubMed

    Dornburg, Alex; Friedman, Matt; Near, Thomas J

    2015-08-01

    Elopomorpha is one of the three main clades of living teleost fishes and includes a range of disparate lineages including eels, tarpons, bonefishes, and halosaurs. Elopomorphs were among the first groups of fishes investigated using Hennigian phylogenetic methods and continue to be the object of intense phylogenetic scrutiny due to their economic significance, diversity, and crucial evolutionary status as the sister group of all other teleosts. While portions of the phylogenetic backbone for Elopomorpha are consistent between studies, the relationships among Albula, Pterothrissus, Notacanthiformes, and Anguilliformes remain contentious and difficult to evaluate. This lack of phylogenetic resolution is problematic as fossil lineages are often described and placed taxonomically based on an assumed sister group relationship between Albula and Pterothrissus. In addition, phylogenetic studies using morphological data that sample elopomorph fossil lineages often do not include notacanthiform or anguilliform lineages, potentially introducing a bias toward interpreting fossils as members of the common stem of Pterothrissus and Albula. Here we provide a phylogenetic analysis of DNA sequences sampled from multiple nuclear genes that include representative taxa from Albula, Pterothrissus, Notacanthiformes and Anguilliformes. We integrate our molecular dataset with a morphological character matrix that spans both living and fossil elopomorph lineages. Our results reveal substantial uncertainty in the placement of Pterothrissus as well as all sampled fossil lineages, questioning the stability of the taxonomy of fossil Elopomorpha. However, despite topological uncertainty, our integration of fossil lineages into a Bayesian time calibrated framework provides divergence time estimates for the clade that are consistent with previously published age estimates based on the elopomorph fossil record and molecular estimates resulting from traditional node-dating methods.

  11. Infrapopulations of Gyliauchen volubilis Nagaty, 1956 (Trematoda: Gyliauchenidae) in the rabbitfish Siganus rivulatus (Teleostei: Siganidae) from the Saudi coast of the Red Sea.

    PubMed

    Al-Jahdali, M O

    2012-08-01

    In hermaphroditic helminth parasites, infrapopulation size or mating group size mostly affects some processes acting within the infrapopulation. Here, 30 natural infrapopulations (12-154 individuals) of the intestinal trematode Gyliauchen volubilis Nagaty, 1956 from the fish Siganus rivulatus consisting of newly excysted juveniles, immature and mature worms were found distributed in a well-defined fundamental niche (anterior 40% of the intestine). In small infrapopulations, all stages of the parasite were alive. In larger infrapopulations, differential mortality was only and consistently observed among newly excysted juveniles, and gradually increased to include most or all juveniles in the largest infrapopulations. Among mature worms, the mean worm length seemed unaffected by the infrapopulation size. However, the ratio mean testis size-mean ovary size, a reliable indicator of resource allocation to the male function and of opportunities for cross fertilization, significantly increased with mating group size. In small infrapopulations, all stages of the parasite were scattered along the niche, and never seen in mating pairs (possibly reproduced by self-fertilization). In larger infrapopulations, newly excysted juveniles and immature worms were scattered along the anterior two thirds of the niche, while mature worms were constantly found aggregated in its posterior third (narrow microhabitat), where some were arranged in mating pairs. The probability of mating reciprocally or unilaterally was dependent on body size. The mean number of uterine eggs per worm significantly decreased and their mean sizes significantly increased with mating group size. The results are statistically significant and suggest that infrapopulation self-regulation is greatly associated with its size.

  12. Infrapopulations of Procamallanus elatensis Fusco & Overstreet, 1979 (Nematoda: Camallanidae) in the rabbitfish Siganus rivulatus (Teleostei, Siganidae) from the Saudi coast of the Red Sea.

    PubMed

    Al-Jahdali, Mohammed O

    2012-09-01

    Factors regulating gastrointestinal nematode infrapopulations are to a great extent density-dependent. Here, 23 natural infrapopulations (41-281 individuals) of the viviparous nematode Procamallanus elatensis (Camallanidae) from the fish Siganus rivulatus were found distributed in a well-defined fundamental niche (posterior 55% of the intestine). Immature worms were mostly found in the anterior third of this niche, while mature worms were found in aggregations posterior to them and followed by gravid females in the posterior 20% of the intestine. This distribution strongly suggests that worms migrate towards the posterior intestine while they mature, copulate and reproduce. In small infrapopulations, the sex ratios were distinctly female-biased and the number of gravid females was low. In large infrapopulations, the sex ratios were distinctly male-biased and the number of gravid females was high. However, the mean lengths of both immature males and females and mature females decreased dramatically as the infrapopulation size increased, while those of mature males increased significantly. These results strongly suggest intraspecific competition and density-dependent regulation of mean worm length, and the increase in the mean length of mature males strongly suggests intense sexual selection and competition between mature males. Production of larvae by female worms decreased significantly as the infrapopulation size increased, suggesting a density-dependent reduction in female worm fertility. The results are statistically significant and strongly suggest that infrapopulation self-regulation is through density-dependent mechanisms, in which development of immature worms, infrapopulation size, sex ratio, sexual selection and carrying capacity of the fundamental niche play essential roles in shaping and regulating the infrapopulations.

  13. Seven new species within western Atlantic Starksia atlantica, S. lepicoelia, and S. sluiteri (Teleostei, Labrisomidae), with comments on congruence of DNA barcodes and species

    PubMed Central

    Baldwin, Carole C.; Castillo, Cristina I.; Weigt, Lee A.; Benjamin C., Victor

    2011-01-01

    Abstract Specimens of Starksia were collected throughout the western Atlantic, and a 650-bp portion of the mitochondrial gene cytochrome oxidase-c subunit I (COl) was sequenced as part of a re-analysis of species diversity of western Central Atlantic shorefishes. A neighbor-joining tree constructed from the sequence data suggests the existence of several cryptic species. Voucher specimens from each genetically distinct lineage and color photographs of vouchers taken prior to dissection and preservation were examined for diagnostic morphological characters. The results suggest that Starksia atlantica, Starksia lepicoelia, and Starksia sluiteri are species complexes, and each comprises three or more species. Seven new species are described. DNA data usually support morphological features, but some incongruence between genetic and morphological data exists. Genetic lineages are only recognized as species if supported by morphology. Genetic lineages within western Atlantic Starksia generally correspond to geography, such that members of each species complex have a very restricted geographical distribution. Increasing geographical coverage of sampling locations will almost certainly increase the number of Starksia species and species complexes recognized in the western Atlantic. Combining molecular and morphological investigations is bringing clarity to the taxonomy of many genera of morphologically similar fishes and increasing the number of currently recognized species. Future phylogenetic studies should help resolve species relationships and shed light on patterns of speciation in western Atlantic Starksia. PMID:21594143

  14. Gyrodactylus malalai sp. nov. (Monogenea, Gyrodactylidae) from Nile tilapia, Oreochromis niloticus (L.) and Redbelly tilapia, Tilapia zillii (Gervais) (Teleostei, Cichlidae) in the Lake Turkana, Kenya.

    PubMed

    Přikrylová, Iva; Radim, Blažek; Gelnar, Milan

    2012-06-01

    Gyrodactylus malalai sp. nov. is described from the fin surface of cichlid fishes Oreochromis niloticus (L.) and Tilapia zillii (Gervais) caught in Lake Turkana (Kenya). The new species morphologically resembles Gyrodactylus nyanzae Paperna, 1973, but can be readily distinguished by the shape of the marginal hook sickles and the size of its hamuli. The sequence data of rDNA spanning partial 18S, internal transcribe spacer 1 and 2 and the 5.8S gene is unique within GenBank. Genetically, as most similar Gyrodactylus ergensi Přikrylová, Matějusová, Musilová et Gelnar, 2009 was found (97.5%). Moreover, a specimen of G. cichlidarum from O. niloticus, and a specimen G. ergensi from Sarotherodon galilaeus (L.) were collected during sampling in Kenya. Likewise, additional sampling of O. niloticus from the Blue Nile in Sudan revealed the presence of the newly described species. These findings represent the first records of gyrodactylids in both African countries.

  15. First description of monogenean parasites in Lake Tanganyika: the cichlid Simochromis diagramma (Teleostei, Cichlidae) harbours a high diversity of Gyrodactylus species (Platyhelminthes, Monogenea).

    PubMed

    Vanhove, Maarten P M; Snoeks, Jos; Volckaert, Filip A M; Huyse, Tine

    2011-03-01

    Lake Tanganyika harbours the most diverse endemic cichlid fish assemblage of Africa, but its monogenean fish parasites have not been investigated. Here we report, for the first time, on the Gyrodactylus parasites in this hotspot of fish biodiversity. Haptor morphometrics and nuclear ribosomal DNA sequences revealed 3 new species on Zambian Simochromis diagramma: Gyrodactylus sturmbaueri n. sp., G. thysi n. sp. and G. zimbae n. sp. Their distinct morphology and strong genetic differentiation suggest that they belong to distant lineages within the genus Gyrodactylus, and phylogenetic reconstructions suggest affinities with other genera of gyrodactylids. Additional U-shaped haptoral plates in G. thysi n. sp. and a second large spine-like structure in the male copulatory organ of G. zimbae seem to represent new features for the genus. Such large diversity on a single host species can probably be explained by host-switching events during the course of evolution, in agreement with the generally accepted concept that ecological transfer is an important aspect of gyrodactylid speciation. Additional parasitological surveys on other host species, covering a broader phylogenetic and geographical range, should clarify the evolutionary history of Gyrodactylidae on cichlids in the African Great Lake and other parts of Africa.

  16. The Gyrodactylus (Monogenea, Gyrodactylidae) parasite fauna of freshwater sand gobies (Teleostei, Gobioidei) in their centre of endemism, with description of seven new species.

    PubMed

    Vanhove, Maarten P M; Economou, Alcibiades N; Zogaris, Stamatis; Giakoumi, Sofia; Zanella, Davor; Volckaert, Filip A M; Huyse, Tine

    2014-02-01

    While Gobioidei comprises showcases of (adaptive) radiation, the scientific interest they yielded did not ensure full understanding of goby biodiversity. Even in a well-studied region like Europe, wide knowledge gaps remain. Sand gobies represent one of the few clades whose monogenean parasites have been thoroughly studied. However, in the Balkans, part of the sand gobies' centre of endemism, these parasites were unstudied. We focus on Greek and Croatian freshwater gobies. From five sand goby species, the first parasites are reported, describing seven new Gyrodactylus species. Economidichthys pygmaeus harbours Gyrodactylus benedeni sp. n. and Gyrodactylus dorlodoti sp. n. Its congener E. trichonis hosts G. meelkopae sp. n. Knipowitschia milleri was found to host G. charon sp. n., K. thessala is infected by G. bios sp. n., and K. croatica by G. douglasadamsi sp. n. and G. hellemansi sp. n. Gyrodactylus bubyri was found on its type host K. caucasica. A diverse parasite fauna is expected for a region known for its biodiversity and endemism. The contribution of parasites to species richness in such hotspots is overlooked. The observed species richness per host is rather low compared to the better-studied eastern Atlantic sand gobies. Host vicariance is considered to mediate parasite specificity in this fauna. Some new flatworm species display unique morphological features, such as the remarkable size of the marginal hook sickle proper compared to its foot in the Economidichthys parasites, or a characteristically kinked marginal hook sickle in G. douglasadamsi sp. n. These features reflect their hosts' endemism in the Balkans.

  17. Gyrodactylus species (Monogenea: Gyrodactylidae) on the cichlid fishes of Senegal, with the description of Gyrodactylus ergensi n. sp. from Mango tilapia, Sarotherodon galilaeus L. (Teleostei: Cichilidae).

    PubMed

    Prikrylová, Iva; Matejusová, Iveta; Musilová, Nad'a; Gelnar, Milan

    2009-12-01

    The first record of Gyrodactylus species Nordmann, 1832 on the cichlid fish from Senegal is reported. Gyrodactylus parasites were found on four host species studied, Hemichromis fasciatus, Hemichromis letournaeuxi, Oreochromis niloticus, and Sarotherodon galilaeus. Gyrodactylus cichlidarum Paperna (Bamidgeh 13:14-29, 1968) were collected from H. fasciatus, and its identity was confirmed based on the morphometrical comparison with the holotype specimens of G. cichlidarum. Only one specimen of Gyrodactylus sp. was noted on H. letournaeuxi. The gyrodactylid specimens on O. niloticus and S. galilaeus were described as Gyrodactylus ergensi n. sp. based on the detailed morphometrical analysis supported by sequencing. The haptoral sclerites of G. ergensi n. sp., which closely resemble those of Gyrodactylus nyanzae Paperna, 1973, are compared with the type material and discussed. A partial sequence of the internal transcribed spacer recombinant DNA (ITS rDNA) was obtained from two specimens of G. ergensi, and a close relationship between G. ergensi n. sp. and G. cichlidarum is suggested based on 92% similarity in ITS rDNA region.

  18. New species of Diplectanum (Monogenoidea:Diplectanidae), and proposal of a new genus of the Dactylogyridae from the gills of gerreid fishes (Teleostei) from Mexico and Panama.

    PubMed

    Franco, Edgar F Mendoza; Roche, Dominique G; Torchin, Mark E

    2008-09-01

    While investigating the parasites of several marine fishes from the Western Atlantic, the Southern Gulf of Mexico and Central America (Panama), the following monogenoidean species from the gills of gerreid fishes (Gerreidae) were found: Diplec-tanum gatunense sp. n. (Diplectanidae) and Octouncuhaptor eugerrei gen. et sp. n. (Dactylogyridae) in Eugerres brasilianus (Cuvier) from Gatun Lake in the Panama Canal Watershed, and Diplectanum mexicanum sp. n. in Diapterus rhombeus (Cuvier) from the coast of Campeche State, Mexico. New diplectanid species are distinguished from other species of the genus by the general morphology of the copulatory complex and by the shape of the anchors and bars on the haptor. Octouncuhaptor gen. n. is proposed for its new species having slightly overlapping gonads (testis posterodorsal to the ovary), a dextrolateral vaginal aperture, a copulatory complex consisting of a coiled male copulatory organ with counterclockwise rings with the base articulated to the accessory piece, 8 pairs of hooks and the absence of anchors and bars on haptor. Our analysis of morphological features of Diplectanum species on gerreids evidences that these parasites more closely resemble each other than the known species from sciaenids suggesting that split between gerreids and sciaenids resulted in parasite speciation.

  19. Capoeta coadi, a new species of cyprinid fish from the Karun River drainage, Iran based on morphological and molecular evidences (Teleostei, Cyprinidae)

    PubMed Central

    Alwan, Nisreen H.; Zareian, Halimeh; Esmaeili, Hamid Reza

    2016-01-01

    Abstract As presently recognized, the genus Capoeta includes 24 species, nine of which are known to occur in Iran (Capoeta aculeata, Capoeta capoeta, Capoeta buhsei, Capoeta damascina, Capoeta fusca, Capoeta heratensis, Capoeta mandica, Capoeta saadii and Capoeta trutta) and are distributed in almost all Iranian basins except Sistan and Mashkid. Capoeta coadi sp. n. is a new species from the Karun River, southern Iran, draining into the Arvand Rud (Shatt al-Arab) which drains into the Persian Gulf. It is distinguished from all other species of Capoeta by the combination of the following characters: elongate and usually cylindrical body; 8–9 branched dorsal-fin rays; last unbranched dorsal-fin ray weakly to moderately ossified and serrated along 1/3–2/3 of its length; scales small; 70-84 in lateral line (total); 12–17 scales between dorsal-fin origin and lateral line; 9-11 scales between anal-fin origin and lateral line; 26–32 circum-peduncular scales; 10–13 gill rakers on lower limb of first gill arch; 45–47 total vertebrae; one posterior pair of barbels; bright golden-greenish or silvery body coloration in life; length of the longest dorsal-fin ray 15–22% SL; head length 23–26% SL; mouth width 7–10% SL. Capoeta coadi is also distinguished from all other congeners in the Iranian drainages by fixed diagnostic nucleotide substitutions in the mtDNA COI barcode region and cyt b. It is nested in the Capoeta damascina species complex. PMID:28050161

  20. Delimiting the origin of a B chromosome by FISH mapping, chromosome painting and DNA sequence analysis in Astyanax paranae (Teleostei, Characiformes).

    PubMed

    Silva, Duílio M Z de A; Pansonato-Alves, José Carlos; Utsunomia, Ricardo; Araya-Jaime, Cristian; Ruiz-Ruano, Francisco J; Daniel, Sandro Natal; Hashimoto, Diogo Teruo; Oliveira, Cláudio; Camacho, Juan Pedro M; Porto-Foresti, Fábio; Foresti, Fausto

    2014-01-01

    Supernumerary (B) chromosomes have been shown to contain a wide variety of repetitive sequences. For this reason, fluorescent in situ hybridisation (FISH) is a useful tool for ascertaining the origin of these genomic elements, especially when combined with painting from microdissected B chromosomes. In order to investigate the origin of B chromosomes in the fish species Astyanax paranae, these two approaches were used along with PCR amplification of specific DNA sequences obtained from the B chromosomes and its comparison with those residing in the A chromosomes. Remarkably, chromosome painting with the one-arm metacentric B chromosome probe showed hybridization signals on entire B chromosome, while FISH mapping revealed the presence of H1 histone and 18S rDNA genes symmetrically placed in both arms of the B chromosome. These results support the hypothesis that the B chromosome of A. paranae is an isochromosome. Additionally, the chromosome pairs Nos. 2 or 23 are considered the possible B chromosome ancestors since both contain syntenic H1 and 18S rRNA sequences. The analysis of DNA sequence fragments of the histone and rRNA genes obtained from the microdissected B chromosomes showed high similarity with those obtained from 0B individuals, which supports the intraspecific origin of B chromosomes in A. paranae. Finally, the population hereby analysed showed a female-biased B chromosome presence suggesting that B chromosomes in this species could influence sex determinism.

  1. A new species of Suezichthys (Teleostei: Perciformes: Labridae) from the south-eastern Pacific, with a redefinition of the genus and a key to species.

    PubMed

    Russell, Barry C; Westneat, Mark W

    2013-01-01

    A new species of the fish family Labridae, Suezichthys rosenblatti, is described from specimens collected at Isla San Felix, Isla Juan Fernandez and Isla San Ambrosio, off the coast of Chile. Suezichthys rosenblatti is distinct in having a combination of 11 dorsal fin soft rays and 11 anal fin soft rays. It falls in the group of species that has 1½ scale rows above the lateral line and lack a scaly sheath at the base of the dorsal and anal fins (S. aylingi Russell, S. caudovittatus Russell, S. gracilis (Steindachner & Döderlein) and S. soelae Russell). Unlike other members of this group, S. rosenblatti has haemal arches on vertebrae 10-11 (versus haemal arch only on vertebra 10). The monotypic Nelabrichthys ornatus (Carmichael) is now included in the genus Suezichthys and a revised generic description and key to species of Suezichthys is provided. The occurrence of S. rosenblatti in the south-eastern Pacific and S. ornatus in the south-western Indian Ocean and south Atlantic Ocean represent major range extensions of the genus Suezichthys.

  2. Partitioning of Habitat and Prey by Abundant and Similar-sized Species of the Triglidae and Pempherididae (Teleostei) in coastal waters

    NASA Astrophysics Data System (ADS)

    Platell, M. E.; Potter, I. C.

    1999-02-01

    The aim of this study was to determine whether certain co-occurring and abundant species of the teleost families Triglidae and Pempherididae are segregated spatially and/or by diet, and are thus less likely to be susceptible to competition for resources. Nocturnal otter trawling in shallow (5-15 m) and deeper (20-35 m) waters in four regions along ˜200 km of the south-western Australian coastline collected large numbers of a wide size range of the triglids Lepidotrigla modestaand Lepidotrigla papilioand the pempheridids Pempheris klunzingeriand Parapriacanthus elongatus. Although these four species frequently co-occurred at several sites, each species attained its highest density at different sites, thereby representing a partial segregation of these species by habitat. This even occurred with the congeneric triglid species, with L. modestabeing most abundant in the four deep, offshore sites, while L. papiliowas most numerous at three sites which varied in depth and distance from shore. Although triglids and pempheridids both consumed substantial amounts of amphipods and mysids, only the members of the latter family ingested a large amount of errant polychaetes. The latter difference is assumed to reflect the fact that, in comparison with triglids, pempheridids can swim faster, have a mouth adapted for feeding upwards in the water column and feed at night when errant polychaetes emerge from the substratum. Although the dietary compositions of L. modestaand L. papiliodid not differ significantly when analyses were based on dietary data for all sites, they did differ significantly when analyses were restricted to dietary data obtained when both species were abundant and co-occurred. The likelihood of competition for food is thus reduced in the latter circumstances. In comparison with P. klunzingeri, P. elongatusconsumed a relatively larger volume of amphipods and a relatively smaller volume of mysids, which are more mobile, implying that P. elongatusfeeds to a greater extent on rather than above the substratum surface. The diets of all species underwent ontogenetic changes, which were particularly marked in P. klunzingeriwhere an increase in body size was accompanied by a reduced consumption of mysids and an increased ingestion of errant polychaetes and amphipods. The fact that L. modesta, L. papilio, P. klunzingeriand P. elongatusare partially segregated by habitat and feed on suites of prey which differ in composition, allied with an interfamilial difference in the time of feeding, would reduce the likelihood of competition for resources amongst these four species, when they co-occur and are abundant. Furthermore, ontogenetic changes in diet would reduce the potential for intraspecific competition for food.

  3. Molecular systematics and distribution review of the endemic cyprinid species, Persian chub, Acanthobrama persidis (Coad, 1981) in Southern Iran (Teleostei: Cyprinidae)

    PubMed Central

    Teimori, Azad; Esmaeili, Hamid Reza; Sayyadzadeh, Golnaz; Zarei, Neda; Gholamhosseini, Ali

    2015-01-01

    The Iranian Persian chub is an endemic species of the family Cyprinidae known only from few localities in drainages of Southern Iran. It was originally described in the genus Pseudophoxinus as (Pseudophoxinus persidis) and then Petroleuciscus (as Petroleuciscus persidis). In this study, we examined phylogenetic relationships of the Iranian Persian chub with other relatives in the family Cyprinidae based on the mitochondrial cytochrome b gene to estimate the phylogenetic (and taxonomic) position of the species. Our molecular phylogenies show that new fish sequences from the drainages in southern Iran are clustered with sequences of the genus Acanthobrama from GenBank while the sequences from two other genera (Pseudophoxinus and Petroleuciscus) are in distinct clade. Therefore, we conclude that the populations of Persian Chub in drainages of southern Iran (i.e., Kol, Kor, Maharlu and Persis) belong to the genus Acanthobrama and species Acanthobrama persidis. The predicted geographic distributions for the species showed a large area of suitable climate for A. persidis across south and west of Iran especially in the Kor River basin. Some other parts in the Persis and Tigris are also might have been suitable habitats for this cyprinid species showing possible dispersal route of Acanthobrama from Tigris to the Persis, Kor and Kol basins. PMID:27844011

  4. Cytochrome oxidase 1 gene sequence analysis in six flatfish species (Teleostei, Pleuronectidae) of Far East Russia with inferences in phylogeny and taxonomy.

    PubMed

    Kartavtsev, Yuri Ph; Sharina, Svetlana N; Goto, Tadasuke; Chichvarkhin, Anton Y; Balanov, Andrey A; Vinnikov, Kirill A; Ivankov, Vyacheslav N; Hanzawa, Naoto

    2008-12-01

    Mitochondrial DNA at the cytochrome oxidase 1 (Co-1) gene region was sequenced for six flatfish species (in total, 11 sequences of at least 539 base pairs) from the Far East of Russia and compared with other sequences of Pleuronectiformes, comprising altogether 26 flatfish sequences and two outgroup sequences (Perciformes). An analysis of the protein-coding Co-1 gene revealed a statistically substantiated bias in (T + C):(A + G) content, supporting earlier findings. Average scores of the p-distances for different scales of the evolutionary history at the Co-1 gene revealed a clear pattern of increased nucleotide diversity at four different levels: (1) intraspecies, (2) intragenus, (3) intrafamily, and (4) intra-order. Scores of average p-distances of the four categories of comparison in flatfishes were (1) 0.17 +/- 0.09%, (2) 10.60 +/- 1.57%, (3) 12.40 +/- 0.27%, and (4) 19.93 +/- 0.05%, respectively (mean +/- standard error). These data jointly with current knowledge support the concept that speciation in the order Pleuronectiformes mostly follows a geographic mode through accumulation of numerous small genetic changes over a long period of time. A phylogenetic tree for 26 sequences of flatfishes and two other fishes belonging to ray-finned fishes (Actinopterigii) was developed using the Co-1 gene and four different analytical approaches: neighbour-joining, Bayesian (BA), maximum parsimony (MP), and maximum likelihood. The analysis revealed a monophyletic origin for the representatives of Pleuronectidae, which is the principal flatfish family investigated (73-100% support level in our MP and BA analyses). According to the current and literary data, the monophyletic origin for the six compared flatfish families was well supported. Species identification on a per-individual basis (barcoding tagging) was high.

  5. [Phylogenetic and taxonomic analysis of flatfish species (Teleostei, Pleuronectiformes) inferred from the primary nucleotide sequence of cytochrome oxidase 1 gene (Co-1)].

    PubMed

    Sharina, S N; Kartavtsev, Iu F

    2010-03-01

    Seventeen nucleotide sequences of Co-1 gene from 13 Pleuronectiformes species and 2 Perciformes species served as the outgroup were examined. For divergence comparison, the initial stage involved calculation of pairwise p-distances for all investigated sequences. This allowed to evaluate the nucleotide diversity on four phylogenetically different levels: (1) intraspecific, (2) intrageneric, (3) intrafamilial, and (4) intraordinal. The values of p-distances for the Co-1 gene for the four mentioned categories were (1) 0.93 +/- 0.73%, (2) 11.72 +/- 1.86%, (3) 12.10 +/- 1.10%, and (4) 20.20 +/- 0.22%, respectively. An increase in the level of genetic divergence along with an enhancement in taxon rank was previously reported for different species, which might be explained by prevalence of geographic speciation model in nature. Phylogenetic trees were constructed using four approaches: maximum parsimony, Bayesian, maximum likelihood, and neighbor-joining. These trees demonstrated similar results confirming the monophyletic origin of the families studied. The examined representatives of the flatfish species and genera were shown to be sufficiently divergent genetically.

  6. Cytogenetic analysis of three sea catfish species (Teleostei, Siluriformes, Ariidae) with the first report of Ag-NOR in this fish family.

    PubMed

    Nirchio, Mauro; Martinez, Emanuel Ricardo Monteiro; Foresti, Fausto; Oliveira, Claudio

    2010-04-01

    Despite their ecological and economical importance, fishes of the family Ariidae are still genetically and cytogenetically poorly studied. Among the 133 known species of ariids, only eight have been karyotyped. Cytogenetic analyses performed on Genidens barbus and Sciades herzbergii revealed that both species have 2n = 56 chromosomes and Cathorops aff. mapale has 2n = 52 chromosomes: Genidens barbus has 10 Metacentrics (M), 14 Submetacentrics (SM), 26 Subtelocentrics (ST), and 6 Acrocentrics (A), Sciades herzbergii has 14M, 20SM, 18ST and 4A, whereas Cathorops aff. mapale has 14M, 20SM, and 18ST. The nucleolus organizer regions (NORs) were found in a single chromosome pair on the short arm of a large-sized ST pair in Genidens barbus and on the short arm of a middle-size SM pair in Cathorops aff. mapale. Multiple NORs on the short arms of two large-sized ST pairs were found in Sciades herzbergii. The occurrence of diploid numbers ranging from 2n = 52 through 56 chromosomes and the presence of different karyotypic compositions, besides the number and position of NORs suggest that several numeric and structural chromosome rearrangements were fixed during the evolutionary history of this fish family.

  7. Localization of 18S ribosomal genes in suckermouth armoured catfishes Loricariidae (Teleostei, Siluriformes) with discussion on the Ag-NOR evolution

    PubMed Central

    Alves, Anderson Luis; de Borba, Rafael Splendore; Pozzobon, Allan Pierre Bonetti; Oliveira, Claudio; Nirchio, Mauro; Granado, Angel; Foresti, Fausto

    2012-01-01

    Abstract The family Loricariidae with about 690 species divided into six subfamilies, is one of the world’s largest fish families. Cytogenetic studies conducted in the family showed that among 90 species analyzed the diploid number ranges from 2n=38 in Ancistrus sp. to 2n=96 in Hemipsilichthys gobio Luetken, 1874. In the present study, fluorescence in situ hybridization (FISH) was employed to determine the chromosomal localization of the 18S rDNA gene in four suckermouth armoured catfishes: Kronichthys lacerta (Nichols, 1919), Pareiorhaphis splendens (Bizerril, 1995), Liposarcus multiradiatus (Hancock, 1828) and Hypostomus prope plecostomus (Linnaeus, 1758). All species analyzed showed one chromosome pair with 18S rDNA sequences, as observed in the previous Ag-NORs analyses. The presence of size and numerical polymorphism was observed and discussed, with proposing a hypothesis of the Ag-NOR evolution in Loricariidae. PMID:24260671

  8. Karyotypic diversity and evolutionary trends in the Neotropical catfish genus Hypostomus Lacépède, 1803 (Teleostei, Siluriformes, Loricariidae)

    PubMed Central

    Alves, Anderson Luis; de Borba, Rafael Splendore; Oliveira, Claudio; Mauro Nirchio; Granado, Angel; Foresti, Fausto

    2012-01-01

    Abstract The family Loricariidae with 813 nominal species is one of the largest fish families of the world. Hypostominae, its more complex subfamily, was recently divided into five tribes. The tribe Hypostomini is composed of a single genus, Hypostomus Lacépède, 1803, which exhibits the largest karyotypic diversity in the family Loricariidae. With the main objective of contributing to a better understanding of the relationship and the patterns of evolution among the karyotypes of Hypostomus species, cytogenetic studies were conducted in six species of the genus from Brazil and Venezuela. The results show a great chromosome variety with diploid numbers ranging from 2n=68 to 2n=76, with a clear predominance of acrocentric chromosomes. The Ag-NORs are located in terminal position in all species analyzed. Three species have single Ag-NORs (Hypostomus albopunctatus (Regan, 1908), Hypostomus prope plecostomus (Linnaeus, 1758), and Hypostomus prope paulinus (Ihering, 1905)) and three have multiple Ag-NORs (Hypostomus ancistroides (Ihering, 1911), Hypostomus prope iheringi (Regan, 1908), and Hypostomus strigaticeps (Regan, 1908)). In the process of karyotype evolution of the group, the main type of chromosome rearrangements was possibly centric fissions, which may have been facilitated by the putative tetraploid origin of Hypostomus species. The relationship between the karyotype changes and the evolution in the genus is discussed. PMID:24260683

  9. Local ecological knowledge of the artisanal fishers on Epinephelus itajara (Lichtenstein, 1822) (Teleostei: Epinephelidae) on Ilhéus coast – Bahia State, Brazil

    PubMed Central

    2014-01-01

    Background Local Ecological Knowledge (LEK) of traditional fishermen may be the only source of information regarding the conservation of the marine ecosystem and its endangered species. One of these species is Epinephelus itajara, which can exceed 2 m in length and 400 kg weight, is classified by the IUCN as a critically endangered. In Brazil, there is currently a moratorium that prohibits the capture of this specie, and in the northeastern coast, a Marine Protected Area was recently established properly justified by the existence a one spawning aggregation. The scope of the present study was the analysis the LEK of fishers with the goal of contributing to the conservation of E. Itajara. Methods The Knowledge of 24 “experts” was recorded through semi-structured interviews with fishermen selected based on their expertise. LEK regarding some aspects of the life history of E. itajara, such as its morphology, spatial distribution, feeding, breeding and conservation, was systematized. The interviews were conducted in synchronic and diachronic situations. The data analysis followed the model of unity of the various individual skills, while the consistency of the analysis was tested using a matrix of methods employed in comparative cognitive science. Potential reproductive aggregation sites were identified by experts through projective interviews conducted based on a cartographic database and transferred to a geographic information system (GIS). Results The LEK of these specialists in relation to the biological and ecological characteristics of E. itajara showed a high level of detail and a high agreement with the scientific literature. Projective interviews are presented as a promising tool allowing spatialization of the information generated through the registration of LEK. Therefore, the visualization of information from the fishermen, as well as its analysis and comparison with other databases, is simplified, thereby contributing to the decision-making process concerning the conservation of marine ecosystem in Brazil. Conclusions Integration of LEK with scientific knowledge is an efficient strategy for the conservation of endangered species, as it provides important additional biological information that can be used in the process of participative and sustainable management of marine resources. PMID:24965849

  10. Two new species of Haliotrema Johnston & Tiegs, 1922 (Monogenea: Dactylogyridae) from Acanthurus nigrofuscus (Forsskål) and A. triostegus (Linnaeus) (Teleostei: Acanthuridae) in the South China Sea.

    PubMed

    Sun, Yuan; Yang, Chaopin; Yang, Tingbao

    2015-07-01

    Haliotrema nanhaiense n. sp. and Haliotrema triostegum n. sp. are described respectively from the gills of Acanthurus nigrofuscus (Forsskål) and Acanthurus triostegus (Linnaeus) in the South China Sea. Haliotrema nanhaiense n. sp. differs from other existing congeneric species by its male copulatory complex, comprising a C-shaped copulatory tube, a saucer-shaped base and a sickle-shaped accessory piece. Haliotrema triostegum n. sp. can be differentiated from all other members of Haliotrema by having a unique copulatory complex, a cup-shaped base, inverted L-shaped copulatory tube with a small sclerotised piece arising from its distal portion, and a large accessory piece from the proximal portion of copulatory tube.

  11. Embryonic and larval development of jundiá (Rhamdia quelen, Quoy and Gaimard, 1824, Pisces, TeleosteI), a South American catfish.

    PubMed

    Pereira, C R; Barcellos, L J G; Kreutz, L C; Quevedo, R M; Ritter, F; Silva, L B

    2006-11-01

    The jundiá (Rhamdia quelen, Quoy and Gaimard) is an endemic South American fish species. Because this species supports cold winters and grows faster during warm months, it has begun to be viewed as an ideal species for fish production in southern South America. In the present study, jundiá oocytes used were obtained by extrusion from females after hormone injection. Soon after hydration, the eggs were transferred to 50 L conic glass incubators, with constant and controlled water influx. Samples of fertilized eggs were transferred to Petri dishes and, examined under a stereoscopic microscope, were spherical, demersal, and non-adhesive with defined perivitelline space and resistant chorion. Cleavage stages occurred during the first 3.5 h. After hatching, larvae were transferred to 200 L glass fiber incubators. First signs of embryo movement were observed 21 h after fertilization; larval eclosion occurred 30.5 h after fertilization. Present findings may provide a basis for studies aimed at determining the complete ontogeny of jundiá and may be useful in eco-toxicological studies.

  12. Heliconema longissimum (Ortlepp, 1923) (Nematoda: Physalopteridae) from Pisodonophis boro (Teleostei: Ophichthidae) in Thailand, with remarks on the taxonomy of the Proleptinae Schulz, 1927.

    PubMed

    Moravec, Frantisek; Taraschewski, Horst; Anantaphruti, Malinee Thairungroj; Maipanich, Wanna; Laoprasert, Thitiporn

    2007-01-01

    Physalopterid nematodes identified as Heliconema longissimum (Ortlepp, 1923) were collected from the stomach of rice-paddy eels Pisodonophis boro (Hamilton) (Anguilliformes: Ophichthidae) from two brackish-water localities (mangroves) in Thailand: one in Phan-Nga Province, southwestern Thailand, northeast of Phuket Island, and one in Ranong Province, near the border with Myanmar. Study of the morphology of this hitherto insufficiently known nematode species, including its first SEM examination, enabled a detailed redescription of H. longissimum. Present taxonomic problems in the subfamily Proleptinae Schulz, 1927 are discussed, where a new delimitation of Proleptus Dujardin, 1845, Heliconema Travassos, 1919 and Paraleptus Wu, 1927 is proposed based on the cephalic dentation. H. minnanensis [sic] Damin & Heqing, 2001 is transferred to Paraleptus Wu, 1927 as P. minnanensis (Damin & Heqing, 2001) n. comb. and Paraleptus chiloscyllii Yin & Zhang, 1983 transferred by Damin & Heqing (2001) to Heliconema, is retained in Paraleptus. H. ahiri Karve, 1941 is considered a junior synonym of H. longissimum (Ortlepp, 1923). The present finding of H. longissimum in Pisodonophis boro represents the first host record and the first record of this nematode from Thailand.

  13. Delimiting the Origin of a B Chromosome by FISH Mapping, Chromosome Painting and DNA Sequence Analysis in Astyanax paranae (Teleostei, Characiformes)

    PubMed Central

    Silva, Duílio M. Z. de A.; Pansonato-Alves, José Carlos; Utsunomia, Ricardo; Araya-Jaime, Cristian; Ruiz-Ruano, Francisco J.; Daniel, Sandro Natal; Hashimoto, Diogo Teruo; Oliveira, Cláudio; Camacho, Juan Pedro M.; Porto-Foresti, Fábio; Foresti, Fausto

    2014-01-01

    Supernumerary (B) chromosomes have been shown to contain a wide variety of repetitive sequences. For this reason, fluorescent in situ hybridisation (FISH) is a useful tool for ascertaining the origin of these genomic elements, especially when combined with painting from microdissected B chromosomes. In order to investigate the origin of B chromosomes in the fish species Astyanax paranae, these two approaches were used along with PCR amplification of specific DNA sequences obtained from the B chromosomes and its comparison with those residing in the A chromosomes. Remarkably, chromosome painting with the one-arm metacentric B chromosome probe showed hybridization signals on entire B chromosome, while FISH mapping revealed the presence of H1 histone and 18S rDNA genes symmetrically placed in both arms of the B chromosome. These results support the hypothesis that the B chromosome of A. paranae is an isochromosome. Additionally, the chromosome pairs Nos. 2 or 23 are considered the possible B chromosome ancestors since both contain syntenic H1 and 18S rRNA sequences. The analysis of DNA sequence fragments of the histone and rRNA genes obtained from the microdissected B chromosomes showed high similarity with those obtained from 0B individuals, which supports the intraspecific origin of B chromosomes in A. paranae. Finally, the population hereby analysed showed a female-biased B chromosome presence suggesting that B chromosomes in this species could influence sex determinism. PMID:24736529

  14. The Afro-Asian labeonine genus Garra Hamilton, 1822 (Teleostei, Cyprinidae) in the Pliocene of Central Armenia: Palaeoecological and palaeobiogeographical implications

    NASA Astrophysics Data System (ADS)

    Vasilyan, Davit; Carnevale, Giorgio

    2013-01-01

    Fossil skeletal remains of the Afro-Asian labeonine genus Garra are described on the basis of more than 300 specimens from the Pliocene diatomites of Jradzor, Central Armenia. Extant species of the genus Garra exhibit a wide distribution ranging from China, South Asia, and Borneo, through Middle East, the Arabian Peninsula, and Africa, where these fishes inhabit a variety of freshwater biotopes. The Pliocene fossils from the Jradzor site provide the first evidence of Garra in the fossil record. The inadequate preservation of the available material did not allow a detailed taxonomic attribution at the species level. Remains of Garra sp. were found associated to a moderately diverse assemblage, which includes also remains of additional freshwater fishes (Capoeta sp., Leuciscus cf. souffia, Leuciscus sp.), amphibians (Pelophylax cf. ridibundus), and large mammals (Rhinocerotidae indet.), as well as of monocotyledon plants. According to the diatom flora, the diatomites of Jradzor can be assigned to the Pliocene and were deposited in a freshwater lacustrine setting that was characterized by high productivity, eutrophic conditions, and standing macrophyte vegetation along the littoral zone. The presence of abundant resorptive pharyngeal teeth suggests that the Pliocene palaeolake of Jradzor was characterized by resident populations of Garra. Extant species of this genus are currently absent in the freshwaters of Armenia. The record of the genus Garra from Jradzor suggests that the Araks-Kura River drainage was connected, at least in part, with the Euphrates and Tigris River drainage during the Pliocene. The extinction of Garra (and other thermophilous taxa) from Araks and Kura River drainage was probably due to Plio-Pleistocene tectonic uplift of the Armenian Highland and consequent progressive climate cooling.

  15. Pathological and histometric analysis of the gills of female Hyphessobrycon eques (Teleostei:Characidae) exposed to different concentrations of the insecticide Dimilin(®).

    PubMed

    Marcon, Lucas; Lopes, Diego Senra; Mounteer, Ann Honor; Goulart, Amara Manarino Andrade; Leandro, Mila Vasques; Dos Anjos Benjamin, Laércio

    2016-09-01

    Female individuals of Hyphessobrycon eques were exposed to Diflubenzuron (Dimilin(®)) in order to determine whether exposure to sublethal levels of this insecticide causes changes in gill morphology. Fish were exposed to 0.01, 0.1 and 1.0mgL(-1) for 96h and 17 days and then submitted to pathological and histometric evaluation. Pathological lesions, such as hyperplasia, lamellar fusion, vascular congestion, secondary lamellar disarray, vasodilatation, hemorrhage and increased lamellar epithelium, were significantly more common in the gills of fish exposed to Dimilin(®) than the control. Histometric analysis documented significant changes in blood vessel diameter, primary lamellae width and secondary lamellae length, and the appearance of hemorrhage foci in all concentrations tested. Even at low Dimilin(®) concentrations, the histopathological alteration index was mild to moderate, thereby indicating that the function of this tissue was compromised. These findings indicate that indiscriminate use of Dimilin(®) can adversely affect the structural integrity of the gills of H. eques, which can cause numerous problems for fish farming systems.

  16. Asexual Reproduction Does Not Apparently Increase the Rate of Chromosomal Evolution: Karyotype Stability in Diploid and Triploid Clonal Hybrid Fish (Cobitis, Cypriniformes, Teleostei)

    PubMed Central

    Majtánová, Zuzana; Choleva, Lukáš; Symonová, Radka; Ráb, Petr; Kotusz, Jan; Pekárik, Ladislav; Janko, Karel

    2016-01-01

    Interspecific hybridization, polyploidization and transitions from sexuality to asexuality considerably affect organismal genomes. Especially the last mentioned process has been assumed to play a significant role in the initiation of chromosomal rearrangements, causing increased rates of karyotype evolution. We used cytogenetic analysis and molecular dating of cladogenetic events to compare the rate of changes of chromosome morphology and karyotype in asexually and sexually reproducing counterparts in European spined loach fish (Cobitis). We studied metaphases of three sexually reproducing species and their diploid and polyploid hybrid clones of different age of origin. The material includes artificial F1 hybrid strains, representatives of lineage originated in Holocene epoch, and also individuals of an oldest known age to date (roughly 0.37 MYA). Thereafter we applied GISH technique as a marker to differentiate parental chromosomal sets in hybrids. Although the sexual species accumulated remarkable chromosomal rearrangements after their speciation, we observed no differences in chromosome numbers and/or morphology among karyotypes of asexual hybrids. These hybrids possess chromosome sets originating from respective parental species with no cytogenetically detectable recombinations, suggesting their integrity even in a long term. The switch to asexual reproduction thus did not provoke any significant acceleration of the rate of chromosomal evolution in Cobitis. Asexual animals described in other case studies reproduce ameiotically, while Cobitis hybrids described here produce eggs likely through modified meiosis. Therefore, our findings indicate that the effect of asexuality on the rate of chromosomal change may be context-dependent rather than universal and related to particular type of asexual reproduction. PMID:26808475

  17. Morphological aspects of Henneguya aequidens n. sp. (Myxozoa: Myxobolidae) in Aequidens plagiozonatus Kullander, 1984 (Teleostei: Cichlidae) in the Amazon region, Brazil.

    PubMed

    Videira, Marcela; Velasco, Michele; Azevedo, Rodney; Silva, Reinaldo; Gonçalves, Evonnildo; Matos, Patrícia; Matos, Edilson

    2015-03-01

    A new species of Myxosporea, Henneguya aequidens sp. n. (Myxozoa: Myxobolidae), was described based on its ultrastructural features. This is a parasite of the freshwater fish Aequidens plagiozonatus, in the Peixe-boi River, Pará, Brazil. This parasite was found in the gills, in the form of whitish ellipsoid cysts with mature spores inside them. The average spore body was 15 ± 0.9 μm in length (n = 30) and 6 ± 0.8 μm in width (n = 30), and the tail measured 27 ± 0.5 μm in length (n = 15). The spores showed typical features of the genus Henneguya with two valves of equal size and two symmetrical polar capsules of 3 ± 0.3 μm in length and 2 ± 0.3 μm in width. Each polar capsule had a polar filament forming a helix from the apical region to the polar caps, with four to six turns. Based on the ultrastructural differences in morphology of these spores, the location of the parasite, and its host specificity, this parasite was described as a new species.

  18. Myxidium volitans sp. nov., a parasite of the gallbladder of the fish, Dactylopterus volitans (Teleostei: Triglidae) from the Brazilian Atlantic coast--morphology and pathology.

    PubMed

    Azevedo, Carlos; Casal, Graça; São Clemente, Sérgio Carmona; Lopes, Leila Maria Silva; Matos, Patrícia; Abdel-Baki, Abdel Azeem; Oliveira, Elsa; Matos, Edilson

    2011-08-01

    Myxidium volitans sp. nov. (Myxozoa: Myxidiidae) parasitizing the hypertrophied green-brownish gallbladder of the teleost Dactylopterus volitans, collected in the Atlantic coast near Niterói, Brazil was described based on ultrastructural studies. The spores were fusiform, sometimes slightly crescent-shaped on average 21.7 ± 0.3 µm (mean ± standard deviation) (n = 50) long and 5.6 ± 0.4 µm (n = 30) wide. The spore wall was thin and smooth, comprising two equally-sized valves joined by a hardly visible sutural ridge. Spores containing two pyriform polar capsules (PC) (5.0 ± 0.4 × 2.3 ± 0.3 µm) (n = 30) are situated in each extremity of the spore. The PC wall was composed of hyaline layer (0.20-0.29 µm thick) and by a thin external granular layer. Each PC contains a polar filament (PF) with irregular arrangements that was projected from its apical region to the bases of PC and coiled laterally from bases to the tip of PC. Some regular striations and S-like structures in the periphery of the PFs with four-five irregular sections were observed. Based on the spore morphology, ultrastructural differences and the specificity of the host we describe this parasite as a new myxosporidian, named M. volitans sp. nov.

  19. Population Structure, Genetic Diversity, Effective Population Size, Demographic History and Regional Connectivity Patterns of the Endangered Dusky Grouper, Epinephelus marginatus (Teleostei: Serranidae), within Malta's Fisheries Management Zone.

    PubMed

    Buchholz-Sørensen, Molly; Vella, Adriana

    2016-01-01

    The objective of this study is to describe the genetic population structure and demographic history of the endangered marine fish, Epinephelus marginatus, within Malta's Fisheries Management Zone for the purpose of localised conservation planning. Epinephelus marginatus is a long-lived, sedentary, reef-associated protogynous hermaphrodite with high commercial and recreational value that is at risk of extinction throughout its global distribution. Based on global trends, population substructuring and gaps in local knowledge this has led to an increased interest in evaluation of local stock. Assessment of Maltese demography was based on historical and contemporary catch landings data whilst genetic population structure and regional connectivity patterns were evaluated by examining 175 individuals collected within the central Mediterranean region between 2002 and 2009 using 14 nuclear microsatellite loci. Demographic stock assessment of Maltese E. marginatus' revealed a 99% decline in catch landings between 1947 and 2009 within the Fisheries Management Zone. A contemporary modest mean size was observed, 3 ± 3 kg, where approximately 17% of the population was juvenile, 68% female/sex-changing and 15% were male with a male-to-female sex ratio of 1:5. Genetic analysis describes the overall population of E. marginatus' within the Fisheries Management Zone as decreasing in size (ƟH = 2.2), which has gone through a significant size reduction in the past (M = 0.41) and consequently shows signs of moderate inbreeding (FIS = 0.10, p < 0.001) with an estimated effective population size of 130 individuals. Results of spatially explicit Bayesian genetic cluster analysis detected two geographically distinct subpopulations within Malta's Fisheries Management Zone and that they are connected to a larger network of E. marginatus' within the Sicily Channel. Results suggest conservation management should be designed to reflect E. marginatus' within Malta's Fisheries Management Zone as two management units.

  20. Asexual Reproduction Does Not Apparently Increase the Rate of Chromosomal Evolution: Karyotype Stability in Diploid and Triploid Clonal Hybrid Fish (Cobitis, Cypriniformes, Teleostei).

    PubMed

    Majtánová, Zuzana; Choleva, Lukáš; Symonová, Radka; Ráb, Petr; Kotusz, Jan; Pekárik, Ladislav; Janko, Karel

    2016-01-01

    Interspecific hybridization, polyploidization and transitions from sexuality to asexuality considerably affect organismal genomes. Especially the last mentioned process has been assumed to play a significant role in the initiation of chromosomal rearrangements, causing increased rates of karyotype evolution. We used cytogenetic analysis and molecular dating of cladogenetic events to compare the rate of changes of chromosome morphology and karyotype in asexually and sexually reproducing counterparts in European spined loach fish (Cobitis). We studied metaphases of three sexually reproducing species and their diploid and polyploid hybrid clones of different age of origin. The material includes artificial F1 hybrid strains, representatives of lineage originated in Holocene epoch, and also individuals of an oldest known age to date (roughly 0.37 MYA). Thereafter we applied GISH technique as a marker to differentiate parental chromosomal sets in hybrids. Although the sexual species accumulated remarkable chromosomal rearrangements after their speciation, we observed no differences in chromosome numbers and/or morphology among karyotypes of asexual hybrids. These hybrids possess chromosome sets originating from respective parental species with no cytogenetically detectable recombinations, suggesting their integrity even in a long term. The switch to asexual reproduction thus did not provoke any significant acceleration of the rate of chromosomal evolution in Cobitis. Asexual animals described in other case studies reproduce ameiotically, while Cobitis hybrids described here produce eggs likely through modified meiosis. Therefore, our findings indicate that the effect of asexuality on the rate of chromosomal change may be context-dependent rather than universal and related to particular type of asexual reproduction.

  1. Garra mondica, a new species from the Mond River drainage with remarks on the genus Garra from the Persian Gulf basin in Iran (Teleostei: Cyprinidae).

    PubMed

    Sayyadzadeh, Golnaz; Esmaeili, Hamid Reza; Freyhof, Jörg

    2015-11-24

    Garra mondica, new species, from the Mond River drainage in Iran is distinguished from its congeners by having 7½ branched dorsal-fin rays; the breast, belly and back in front of the dorsal-fin origin naked and 9+8 branched caudal-fin rays. Garra mondica is also distinguished from all other congeners in the Persian Gulf basin, except an unidentified species from the Kol River, by having two fixed, diagnostic nucleotide substitutions in the mtDNA COI barcode region. The identity of G. gymnothorax, a nominal species from the Karun River drainage, and G. crenulata, a nominal species from Central Iran, are discussed. Garra populations examined from the Karun have a unique mtDNA COI barcode sequence, but their diagnostic characters are not consistent with the description and syntypes of G. gymnothorax. G. crenulata is considered as a synonym of G. rufa. Two populations of Garra from the Kol River have a sequence of the COI barcode region very similar to G. mondica, but cannot be identified as G. mondica and their identity cannot be resolved here.

  2. Sasanidus, a new generic name for Noemacheilus kermanshahensis Bănărescu & Nalbant, with discussion of Ilamnemacheilus and Schistura (Teleostei; Nemacheilidae).

    PubMed

    Freyhof, Jörg; Geiger, Matthias F; Golzarianpour, Kiavash; Patimar, Rahman

    2016-04-29

    Sasanidus, new genus, is described for Noemacheilus kermanshahensis Bănărescu & Nalbant, endemic to the Karkheh and Karun drainages in Iran. Sasanidus kermanshahensis was initially identified as a species in Oxynoemacheilus, from which it is distinguished by the absence of an external sexual dimorphism (i.e. longer pectoral fin, and nuptial tubercles on fins, head and back in males). Sasanidus is distinguished from all other genera of Nemacheilidae in the Middle East by a combination of the following character states: pelvic-fin origin behind of a vertical of the dorsal-fin origin, anus about one eye diameter in front of the anal-fin origin, dorsal adipose keel absent, a high crest on the bony capsule of the swim bladder present and colour pattern marbled or mottled or with an irregularly shaped midlateral stripe. Ilamnemacheilus longipinnis was examined and no difference could be found between Ilamnemacheilus and Oxynoemacheilus. Therefore, Ilamnemacheilus is treated as a synonym of Oxynoemacheilus. COI barcode sequences from all nemacheilid loach genera occurring in the Middle East and western India are analysed jointly for the first time. The view that Schistura is a paraphyletic assemblage is supported by the clustering of DNA sequences from 45 specimens placed in at least 20 species in the genus Schistura analysed here.

  3. Contribution to the molecular systematics of the genus Capoeta from the south Caspian Sea basin using mitochondrial cytochrome b sequences (Teleostei: Cyprinidae)

    PubMed Central

    Zareian, Halimeh; Esmaeili, Hamid Reza; Heidari, Adeleh; Khoshkholgh, Majid Reza; Mousavi-Sabet, Hamed

    2016-01-01

    Traditionally, Capoeta populations from the southern Caspian Sea basin have been considered as Capoeta capoeta gracilis. Study on the phylogenetic relationship of Capoeta species using mitochondrial cytochrome b gene sequences show that Capoeta population from the southern Caspian Sea basin is distinct species and receive well support (posterior probability of 100%). Based on the tree topologies obtained from Bayesian and Maximum Likelihood methods, three main groups for the studied Capoeta were detected: Clade I) Capoeta trutta group (the Mesopotamian Capoeta group) including closely related taxa (e.g. trutta, turani, barroisi) characterized by having numerous irregular black spots on the dorsal half of the body. This clade was the sister group to all other Capoeta species and its separation occurred very early in evolution possess, so we considered it as O ld Evolutionary Group. Clade II) comprises highly diversified and widespread group, Capoeta damascina complex group (small scale capoeta group), the Anatolian-Iranian group (e.g. banarescui, buhsei, damascina, saadii), characterized by small scales and plain body (absence of irregular black spots on the dorsal half of the body, except in some juveniles) with significantly later speciation event so called Young Evolutionary Group. Clade III) Capoeta capoeta complex group (large scale capoeta group, the Aralo-Caspian group) comprises very closely related taxa characterized by large scales and plain body (absence of irregular black spots on the dorsal half of the body) distributed in Aralo-Caspian water bodies (capoeta, ekmekciae, heratensis, gracilis, sevangi) that has been recently diverged and could be considered as Very Young Evolutionary Group. PMID:28097160

  4. Capoeta coadi, a new species of cyprinid fish from the Karun River drainage, Iran based on morphological and molecular evidences (Teleostei, Cyprinidae).

    PubMed

    Alwan, Nisreen H; Zareian, Halimeh; Esmaeili, Hamid Reza

    2016-01-01

    As presently recognized, the genus Capoeta includes 24 species, nine of which are known to occur in Iran (Capoeta aculeata, Capoeta capoeta, Capoeta buhsei, Capoeta damascina, Capoeta fusca, Capoeta heratensis, Capoeta mandica, Capoeta saadii and Capoeta trutta) and are distributed in almost all Iranian basins except Sistan and Mashkid. Capoeta coadisp. n. is a new species from the Karun River, southern Iran, draining into the Arvand Rud (Shatt al-Arab) which drains into the Persian Gulf. It is distinguished from all other species of Capoeta by the combination of the following characters: elongate and usually cylindrical body; 8-9 branched dorsal-fin rays; last unbranched dorsal-fin ray weakly to moderately ossified and serrated along 1/3-2/3 of its length; scales small; 70-84 in lateral line (total); 12-17 scales between dorsal-fin origin and lateral line; 9-11 scales between anal-fin origin and lateral line; 26-32 circum-peduncular scales; 10-13 gill rakers on lower limb of first gill arch; 45-47 total vertebrae; one posterior pair of barbels; bright golden-greenish or silvery body coloration in life; length of the longest dorsal-fin ray 15-22% SL; head length 23-26% SL; mouth width 7-10% SL. Capoeta coadi is also distinguished from all other congeners in the Iranian drainages by fixed diagnostic nucleotide substitutions in the mtDNA COI barcode region and cyt b. It is nested in the Capoeta damascina species complex.

  5. Redescription of Neoechinorhynchus (Neoechinorhynchus) golvani Salgado-Maldonado, 1978 (Acanthocephala: Neoechinorhynchidae) and description of a new species from freshwater cichlids (Teleostei: Cichlidae) in Mexico.

    PubMed

    Salgado-Maldonado, Guillermo

    2013-05-01

    A redescription of Neoechinorhynchus (Neoechinorhynchus) golvani Salgado-Maldonado (An Inst Biol Univ Nal Autón Méx, Ser Zool 49:35-47, 1978) is presented, based on adult specimens collected from the type host Paraneetroplus fenestratus from the type location, the Lago de Catemaco lake, Veracruz state, Mexico, and its presence is recorded in other cichlids. Detailed studies of N. (N.) golvani using light microscopy revealed some taxonomically important, previously unreported features, such as the size and shape of fully developed adult males and females, and the structure of the eggs. Morphological variability in N. (N.) golvani is described. Based on these data, the geographic distribution of this species is documented. Neoechinorhynchus (Neoechinorhynchus) panucensis n. sp. is described from Herichthys labridens (Pellegrin), Amatitlania nigrofasciata (Günther), and Herichthys cyanoguttatus Baird and Girard (all of them Cichlidae), collected in the Río Atlapexco, a tributary to the upper Río Panuco basin, Hidalgo State, Mexico. This new species stand up alone because of its minute proboscis (♂ 50 × 60, ♀ 42-55 (48.5) × 48-63 (57.7)) and anterior hooks (♂ 27-30 (28.8) × 3-5 (4), ♀ 28-32 (30) × 5 (5)). A key to the species of Neoechinorhynchus recorded from freshwater fishes in Central and South America is included.

  6. Infrapopulations of Sclerocollum saudii Al-Jahdali, 2010 (Acanthocephala: Cavisomidae) in the rabbitfish Siganus rivulatus (Teleostei, Siganidae) from the Saudi coast of the Red Sea.

    PubMed

    Al-Jahdali, M O; Hassanine, R M El-Said

    2012-03-01

    In infrapopulations of helminth parasites, density-dependent effects, through some form of intra- and interspecific competition, play an important role in shaping and regulating the infrapopulations. The mechanisms responsible for these processes have often been observed in laboratory studies and rarely studied under natural conditions. Here, 24 natural infrapopulations (77-447 individuals) of the acanthocephalan Sclerocollum saudii Al-Jahdali, 2010 from the fish Siganus rivulatus consisted of cystacanths, newly excysted juveniles, immature and mature worms, distributed in a well-defined fundamental niche (anterior 60% of the intestine). Each of these stages exhibited a significantly different longitudinal distribution within this niche. In small infrapopulations, cystacanths and newly excysted juveniles were found in the sixth 10% of the intestine, immature worms in the fifth 10% and mature worms in the anterior 40% of the intestine. However, their proportions followed a clear ascending order in each infrapopulation, and the female-male ratios of both immature and mature worms were distinctly female-biased. In large infrapopulations, mature worms existed partially in the site of immature ones, where a differential mortality among immature females was constantly observed. However, the proportions of immature worms increased significantly and those of mature worms decreased significantly, the mean lengths of immature and mature females decreased dramatically and the female-male ratios were distinctly male-biased. The mean sizes of immature and mature males seemed stable through all infrapopulations. The distribution of mature males and females suggests intense male-male competition for access to females, and reveals that larger females are copulated prior to the smaller ones. The results are statistically significant and suggest that infrapopulation self-regulation is through density-dependent mechanisms, in which immature females may play a key role.

  7. Ultrastructural study of spermiogenesis and the spermatozoon of Acanthocephaloides incrassatus (Molin, 1858) (Acanthocephala, Paleacanthocephala, Arhythmacanthidae) from Anguilla anguilla (Pisces, Teleostei) in Urbino ponds (Corsica Island).

    PubMed

    Foata, J; Quilichini, Y; Dal Pos, N; Greani, S; Marchand, B

    2012-07-01

    This study deals with first ultrastructure features of Acanthocephaloides incrassatus (Paleacanthocephala, Arhythmacanthidae), a parasite of the fish Anguilla anguilla, reported for the first time in a Mediterranean pond. The spermiogenesis of A. incrassatus shows original specificities which have never been pointed out to this day in ultrastructural studies on spermiogenesis: the centriolar derivative is divided into two parts of different densities: an electron-dense, and the other, electron-lucent; a ring form has been observed on each side of the axoneme; a centriole with one central element. After the elaboration of a flagellum of 9+2 pattern, the centriole migrates in a nuclear groove. Rapidly, the centriole disappears. Then, the flagellum migration occurs by a series of processes and gives rise to a spermatozoon. The spermatozoon of A. incrassatus presents its own specificities: it exhibits an evolution of the centriolar derivative characterized by only nine peripheral elements deprived of a central element in the anterior part, then nine peripheral and one central element, and finally, nine peripheral elements with two central elements. An assumption is emitted on a probable correspondence of the evolution of the derivative centriolar during the spermiogenesis and the evolution that occurs in the spermatozoon. Protein granules also show different sizes and forms, full or emptied of their contents compared with data on other Acanthocephala.

  8. Acute effects of Benzo[a]pyrene, anthracene and a fuel oil on biomarkers of the common goby Pomatoschistus microps (Teleostei, Gobiidae).

    PubMed

    Vieira, L R; Sousa, A; Frasco, M F; Lima, I; Morgado, F; Guilhermino, L

    2008-06-01

    The objective of this study was to investigate the effects of two different PAHs and a complex petrochemical mixture on the common goby, Pomatoschistus microps, using selected biomarkers as effect criteria. Benzo[a]pyrene (BaP) and anthracene were used as reference substances, while the water accommodated fraction of #4 fuel-oil (#4 WAF) was used as an example of a petrochemical mixture. P. microps was used since it is both a suitable bioindicator and a good test organism. Groups of fish were exposed to different concentrations of each of the test substances for 96 h and the activities of several enzymes commonly used as biomarkers were determined at the end of the bioassays. All the substances inhibited P. microps acetylcholinesterase (AChE) indicating that they have at least one mechanism of neurotoxicity in common: the disruption of cholinergic transmission by inhibition of AChE. An induction of lactate dehydrogenase (LDH) activity was found in fish exposed to BaP or to anthracene, suggesting an increase of the anaerobic pathway of energy production. On the contrary, inhibition of LDH was found in fish exposed to #4 WAF, suggesting a distinct effect of the mixture. An induction of P. microps glutathione S-transferase (GST) activity was found in fish exposed to BaP or to #4 WAF, while an inhibition was observed after exposure to anthracene. These results suggest that GST is involved in the detoxification of BaP and #4 WAF, but not of anthracene. All the substances increased catalase activity and isolated PAHs also increased superoxide dismutase, glutathione reductase and glutathione peroxidase activities, while #4 WAF did not cause significant alterations on these enzymes. These results suggest that all the substances may induce oxidative stress on P. microps, with BaP and anthracene apparently having more oxidative stress potential than #4 WAF.

  9. A new, mesophotic Coryphopterus goby (Teleostei, Gobiidae) from the southern Caribbean, with comments on relationships and depth distributions within the genus

    PubMed Central

    Baldwin, Carole C.; Robertson, D. Ross

    2015-01-01

    Abstract A new species of western Atlantic Coryphopterus is described from mesophotic depths off Curaçao, southern Caribbean. Coryphopterus curasub sp. n., is similar to Coryphopterus dicrus in, among other features, having two prominent pigment spots of roughly equal intensity on the pectoral-fin base, the pelvic fins fused to form a disk, and no pelvic frenum. The two species can be differentiated by body depth (shallower in Coryphopterus curasub at origin of dorsal fin and caudal peduncle); differences in the pigmentation on the head, trunk, and basicaudal region; and usually by total number of rays (spinous plus soft) in the second dorsal fin (10–11, usually 11, in Coryphopterus curasub, 10 in Coryphopterus dicrus). Coryphopterus curasub differs from other Coryphopterus species that have a prominent pigment spot on the lower portion of the pectoral-fin base (Coryphopterus punctipectophorus and Coryphopterus venezuelae) in, among other features, lacking a pelvic frenum. Coryphopterus curasub was collected between 70 and 80 m, the deepest depth range known for the genus. Collections of Coryphopterus venezuelae at depths of 65–69 m extend the depth range of that species by approximately 50 m. Mitochondrial cytochrome c oxidase subunit I (COI) data corroborate the recognition of Coryphopterus curasub as a distinct species but do not rigorously resolve its relationships within the genus. A revised key to the western Atlantic species of Coryphopterus is presented. PMID:26257572

  10. Cryptic speciation reversal in the Etheostoma zonale (Teleostei: Percidae) species group, with an examination of the effect of recombination and introgression on species tree inference.

    PubMed

    Halas, Dominik; Simons, Andrew M

    2014-01-01

    Mitochondrial and nuclear introgression among closely related taxa can greatly complicate the process of determining their phylogenetic relationships. In the Central Highlands of North America, many fish taxa have undergone introgression; in this study, we demonstrate the existence of an unusual introgression event in the Etheostoma zonale species group. We used one mitochondrial and seven nuclear loci to determine the relationships of the taxa within the E. zonale group, and their degree of differentiation. We found evidence of multiple divergent populations within each species; much of the divergence within species has taken place during the Pleistocene. We also found evidence of a previously unknown cryptic species in the Upper Tennessee River which diverged from the remainder of the group during the Pliocene, and has undergone mitochondrial and nuclear introgression with E. zonale, in an apparent process of speciation reversal. We examined the effects that using varying types of recombination tests to eliminate the signal of recombination from nuclear loci would have on the phylogenetic placement of this introgressed lineage in our species tree analyses.

  11. Pseudotrichonotus belos new species, first record of the fish family Pseudotrichonotidae from Australia (Teleostei: Aulopiformes).

    PubMed

    Gill, Anthony C; Pogonoski, John J

    2016-12-05

    Pseudotrichonotus belos new species, described from three specimens trawled in 100-120 m offshore between Exmouth Gulf and Shark Bay, Western Australia, represents the first record of the sand-diving fish family Pseudotrichonotidae from Australian waters. It differs from its two congeners in having a more posteriorly positioned dorsal fin (predorsal length 39.6-41.2 % SL) and fewer dorsal- and anal-fin rays (31-33 and 12, respectively).

  12. Henneguya paraensis n. sp. (Myxozoa; Myxosporea), a new gill parasite of the Amazonian fish Cichla temensis (Teleostei: Cichlidae): morphological and molecular aspects.

    PubMed

    Velasco, Michele; Videira, Marcela; Nascimento, Luciana de Cássia Silva do; Matos, Patrícia; Gonçalves, Evonnildo Costa; Matos, Edilson

    2016-05-01

    The present study describes light microscopy, transmission electron microscopy, and molecular analyses of a myxosporid found parasitizing the gill region of the teleost fish Cichla temensis, collected from the Tocantins River, near Cametá, Pará State, Brazil. The prevalence of infection was 60 %. The spore-containing cysts that were located in the gill lamellae were oval and whitish. The spores had a mean length of 42.3 ± 0.65 μm; fusiform body, 12.8 ± 0.42-μm long and 8.6 ± 0.32-μm wide; each of the two valves exhibited a tapering tail of 29.5 ± 0.73 μm length. The spores had two polar capsules, 7.4 ± 0.16-μm long by 2.6 ± 0.08-μm wide, containing a polar filament with 5-7 twists. The spores differ from the species previously described, and phylogenetic analysis based on spore morphology and molecular aspects indicated that the fish parasite Henneguya sp. has a strong trend to form clades mainly based on the environment and host order/family. Thus, we conclude that the species belongs to the family Myxobolidae, genus Henneguya, which comprises a new species: Henneguya paraensis n. sp.

  13. Salinity tolerance of non-native Asian swamp eels (Teleostei: Synbranchidae) in Florida, USA: Comparison of three populations and implications for dispersal

    USGS Publications Warehouse

    Schofield, P.J.; Nico, L.G.

    2009-01-01

    Three populations of non-native Asian swamp eels are established in peninsular Florida (USA), and comprise two different genetic lineages. To assess potential for these fish to penetrate estuarine habitats or use coastal waters as dispersal routes, we determined their salinity tolerances. Swamp eels from the three Florida populations were tested by gradual (chronic) salinity increases; additionally, individuals from the Miami population were tested by abrupt (acute) salinity increases. Results showed significant tolerance by all populations to mesohaline waters: Mean survival time at 14 ppt was 63 days. The Homestead population, a genetically distinct lineage, exhibited greater tolerance to higher salinity than Tampa and Miami populations. Acute experiments indicated that swamp eels were capable of tolerating abrupt shifts from 0 to 16 ppt, with little mortality over 10 days. The broad salinity tolerance demonstrated by these experiments provides evidence that swamp eels are physiologically capable of infiltrating estuarine environments and using coastal waters to invade new freshwater systems. ?? 2009 US Government.

  14. Gobiesox lanceolatus, a new species of clingfish (Teleostei:  Gobiesocidae) from Los Frailes submarine canyon, Gulf of California, Mexico.

    PubMed

    Hastings, Philip A; Conway, Kevin W

    2017-01-17

    Gobiesox lanceolatus is described from a single specimen collected from 300 meters depth in the Los Frailes submarine canyon in the southwestern Gulf of California. The "Canyon Clingfish" is unique within Gobiesox in having a lanceolate caudal fin, with the central rays longer than those above and below them. It is also distinguished by 14 dorsal-fin rays (first tiny and unsegmented), 11 anal-fin rays, 28 pectoral-fin rays, anus slightly closer to anal-fin origin than to posterior margin of pelvic disc, and dorsal-fin origin in front of vertical from anus. It is most similar to Gobiesox eugrammus, known from Isla Guadelupe, the coast of outer Baja California and southern California. This is the deepest record for a species of Gobiesox and only four other species of clingfishes are known from greater depths.

  15. A new species of freshwater eel-tailed catfish of the genus Tandanus (Teleostei: Plotosidae) from the Wet Tropics Region of Eastern Australia

    USGS Publications Warehouse

    Welsh, Stuart; Jerry, Dean R.; Burrows, Damien

    2014-01-01

    Tandanus tropicanus, new species, is described based on specimens from streams in the wet tropics region of northeast Queensland. Previously, two species were recognized in the genus Tandanus: T. tandanus of eastern Australia and T. bostocki of Western Australia. A combination of meristic and morphometric characters distinguishes the new species from all congeners. Further, taxonomic distinctness based on morphologic differences between the new species and all congeners is corroborated by genetic analyses.

  16. A new monozoic tapeworm, Lobulovarium longiovatum n. g., n. sp. (Cestoda: Caryophyllidea), from barbs Puntius spp. (Teleostei: Cyprinidae) in the Indomalayan region.

    PubMed

    Oros, Mikuláš; Ash, Anirban; Brabec, Jan; Kar, Pradip Kumar; Scholz, Tomáš

    2012-09-01

    A new caryophyllidean cestode is described from barbs Puntius spp. (Cypriniformes: Cyprinidae), with P. sophore (Hamilton) as its type-host, in the Ganges and Brahmaputra river basins in India and Bangladesh, and a new genus, Lobulovarium n. g., is proposed to accommodate it. The genus belongs to the Lytocestidae because its vitelline follicles are situated in the cortex. It is typified by: (i) a peculiar ovary, which is roughly H-shaped, but with asymmetrical, irregular lobes on its ventral and dorsal sides; (ii) an extensive vitellarium formed by numerous vitelline follicles scattered throughout the cortex; (iii) a long, conical postovarian part of the body with numerous vitelline follicles; (iv) a broadly digitate scolex with a slightly protrusible central cone; (v) a single gonopore (male and female genital ducts open via a single pore and a common genital atrium is absent); and (vi) a small number of testes (< 60). Molecular data (partial sequences of the lsrDNA) indicate that Lobulovarium longiovatum n. sp. belongs among the most basal caryophyllidean cestodes, being unrelated to species from siluriform catfishes in the Indomalayan region. Paracaryophyllaeus osteobramensis (Gupta & Sinha, 1984) Hafeezullah, 1993 (syn. Pliovitellaria osteobramensis Gupta & Sinha, 1984) from another cyprinid fish, Osteobrama cotio (Hamilton), in Uttar Pradesh, India, is tentatively transferred to Lobulovarium as L. osteobramense (Gupta & Sinha, 1984) n. comb. It differs from L. longiovatum by having much smaller eggs (length <50 μm versus >90 μm in L. longiovatum), which are spherical (length/width ratio 1:1 versus 2.5-3:1 in the new species), and the presence of vitelline follicles alongside the ovarian lobes (almost completely absent in L. longiovatum).

  17. Distinguishing between Incomplete Lineage Sorting and Genomic Introgressions: Complete Fixation of Allospecific Mitochondrial DNA in a Sexually Reproducing Fish (Cobitis; Teleostei), despite Clonal Reproduction of Hybrids

    PubMed Central

    Choleva, Lukas; Musilova, Zuzana; Kohoutova-Sediva, Alena; Paces, Jan; Rab, Petr; Janko, Karel

    2014-01-01

    Distinguishing between hybrid introgression and incomplete lineage sorting causing incongruence among gene trees in that they exhibit topological differences requires application of statistical approaches that are based on biologically relevant models. Such study is especially challenging in hybrid systems, where usual vectors mediating interspecific gene transfers - hybrids with Mendelian heredity - are absent or unknown. Here we study a complex of hybridizing species, which are known to produce clonal hybrids, to discover how one of the species, Cobitis tanaitica, has achieved a pattern of mito-nuclear mosaic genome over the whole geographic range. We appplied three distinct methods, including the method using solely the information on gene tree topologies, and found that the contrasting mito-nuclear signal might not have resulted from the retention of ancestral polymorphism. Instead, we found two signs of hybridization events related to C. tanaitica; one concerning nuclear gene flow and the other suggested mitochondrial capture. Interestingly, clonal inheritance (gynogenesis) of contemporary hybrids prevents genomic introgressions and non-clonal hybrids are either absent or too rare to be detected among European Cobitis. Our analyses therefore suggest that introgressive hybridizations are rather old episodes, mediated by previously existing hybrids whose inheritance was not entirely clonal. Cobitis complex thus supports the view that the type of resulting hybrids depends on a level of genomic divergence between sexual species. PMID:24971792

  18. Genetic Heterogeneity Reveals On-Going Speciation and Cryptic Taxonomic Diversity of Stream-Dwelling Gudgeons (Teleostei, Cyprinidae) in the Middle Danubian Hydrosystem (Hungary)

    PubMed Central

    Takács, Péter; Bihari, Péter; Erős, Tibor; Specziár, András; Szivák, Ildikó; Bíró, Péter; Csoma, Eszter

    2014-01-01

    Although stream-dwelling gudgeons (Cyprinidae, genus: Gobio) are widespread in Central Europe, the taxonomy of this group and the distribution of its species are still unexplored in detail. The aims of our study are to ascertain taxonomic composition and distribution of the former Gobio gobio superspecies in the inner area of the Carpathian Basin. Since the presence of cryptic species is suspected in this area, we examined the taxonomic and phylogenetic relationships of Central European Gobio taxa by sequencing the mitochondrial DNA control region (mtCR). Additionally, we characterized the genetic structure of 27 stream-dwelling gudgeon populations of this area by Amplified Fragment Length Polymorphism (AFLP). Results of mtCR analysis proved the presence of three species already known as G. obtusirostris (dominant in NW-Hungary), G. gobio (sporadic) and G. carpathicus (sporadic). Additionally, the analysis revealed the existence of one doubtful taxon, G. sp1 (dominant in NE-Hungary), and a new isolated haplogroup (dominant in SW-Hungary). Although Network analysis showed significant detachment among haplogroups, their genetic distances were quite small. Therefore Bayesian phylogenetic analysis showed weak nodal support for the branching pattern both for newly described haplotypes, and for the already accepted species. AFLP data showed distinct population structure and a clear pattern of isolation was revealed by distance of stocks. At the same time, level of separation was not affected by the altitudinal position of sites. Moreover we found three major clusters of populations which were separated according to hydrographic regions, and corresponded to the findings of mtCR analysis. Our results suggest the on-going speciation of gudgeons in the Carpathian Basin, however the separation of haplogroups seems to only be an intermediate phase. The discovered natural pattern seems to be only slightly influenced by anthropogenic impacts. Additionally our results put into question the suitability of the recently accepted within Gobio genus taxonomy. PMID:24824751

  19. Chromosomal organization of repetitive DNA sequences in Astyanax bockmanni (Teleostei, Characiformes): dispersive location, association and co-localization in the genome.

    PubMed

    Silva, Duílio M Z A; Pansonato-Alves, José Carlos; Utsunomia, Ricardo; Daniel, Sandro Natal; Hashimoto, Diogo Teruo; Oliveira, Claudio; Porto-Foresti, Fabio; Foresti, Fausto

    2013-09-01

    Repetitive DNA sequences constitute a great portion of the genome of eukaryotes and are considered key components to comprehend evolutionary mechanisms and karyotypic differentiation. Aiming to contribute to the knowledge of chromosome structure and organization of some repetitive DNA classes in the fish genome, chromosomes of two allopatric populations of Astyanax bockmanni were analyzed using classic cytogenetics techniques and fluorescent in situ hybridization, with probes for ribosomal DNA sequences, histone DNA and transposable elements. These Astyanax populations showed the same diploid number (2n = 50), however with differences in chromosome morphology, distribution of constitutive heterochromatin, and location of 18S rDNA and retroelement Rex3 sites. In contrast, sites for 5S rDNA and H1, H3 and H4 histones showed to be co-located and highly conserved. Our results indicate that dispersion and variability of 18S rDNA and heterochromatin sites are not associated with macro rearrangements in the chromosome structure of these populations. Similarly, distinct evolutionary mechanisms would act upon histone genes and 5S rDNA, contributing to chromosomal association and co-location of these sequences. Data obtained indicate that distinct mechanisms drive the spreading of repetitive DNAs in the genome of A. bockmanni. Also, mobile elements may account for the polymorphism of the major rDNA sites and heterochromatin in this genus.

  20. The median-fin skeleton of the Eastern Atlantic and Mediterranean clingfishes Lepadogaster lepadogaster (Bonnaterre) and Gouania wildenowi (Risso) (Teleostei: Gobiesocidae).

    PubMed

    Konstantinidis, Peter; Conway, Kevin W

    2010-02-01

    Previous research on the osteology of the Gobiesocidae focused mostly on the neurocranium and the thoracic sucking disc (formed by the paired-fin girdles). Little attention has been paid to the skeleton of the median fins. The dorsal- and anal-fin skeleton of Lepadogaster lepadogaster and other gobiesocids (excluding Alabes, which lacks these fins) are characterized by the absence of spines, branched fin-rays, and middle radials. In gobiesocids, the distal radials never ossify and consist of elastic hyaline-cell cartilage. Gouania wildenowi is unique among gobiesocids in having further reductions of the dorsal- and anal-fin skeleton, including a notable decrease in the size of the proximal-middle radials in an anterior-posterior direction. Unlike L. lepadogaster, which exhibits a one-to-one relationship between the dorsal- and anal-fin rays and proximal-middle radials, G. wildenowi has a higher number of proximal-middle radials than distal radial cartilages and fin rays in the dorsal and anal fins. In G. wildenowi, the dorsal- and anal-fin rays do not articulate with the distal tip of the proximal-middle radials but are instead positioned between proximal-middle radials, which is unusual for teleosts. Previously unrecognized dorsal and ventral pads of elastic hyaline-cell cartilage are also present in the caudal skeleton of L. lepadogaster, G. wildenowi, and all other gobiesocids examined.

  1. A review of the Pseudobarbus afer (Peters, 1864) species complex (Teleostei, Cyprinidae) in the eastern Cape Fold Ecoregion of South Africa

    PubMed Central

    Chakona, Albert; Skelton, Paul H.

    2017-01-01

    Abstract The Eastern Cape redfin, Pseudobarbus afer, has long been considered to be a single widespread and variable species occurring in multiple isolated river systems in the Cape Fold Ecoregion (CFE) at the southern tip of Africa. Mitochondrial cytochrome b and control region sequence data of individuals from populations currently assigned to Pseudobarbus afer across the species’ distribution range revealed existence of four deeply divergent taxonomic units: (i) the Mandela lineage confined to the Sundays, Swartkops and Baakens river systems, (ii) the Krom lineage endemic to the Krom River system, (iii) the St Francis lineage occurring in the Gamtoos and adjacent river systems, and (iv) the Forest lineage occurring in several coastal river systems from the Tsitsikamma to the Klein Brak River system. The Forest lineage is closely related to Pseudobarbus phlegethon from the Olifants River system on the west coast of South Africa, suggesting that it does not belong to Pseudobarbus afer s.l. Herein we focus on the three lineages within the Pseudobarbus afer s.l. complex and provide new diagnosis for Pseudobarbus afer s.s (Mandela lineage), revalidate Pseudobarbus senticeps (Krom lineage) as a distinct species, and describe a new species Pseudobarbus swartzi (St Francis lineage). The three species exhibit subtle differences, which explains why they were previously considered to represent a single variable and widespread species. Pseudobarbus senticeps differs from both Pseudobarbus afer and Pseudobarbus swartzi by having fewer (i.e. larger) scales (25–33, mode 29 lateral line scale series; 10–12, mode 11 circumpeduncular scales) and presence of a lateral stripe which terminates in a conspicuous triangular blotch at the base of the caudal fin. Long barbels which reach or surpass the vertical through the posterior edge of the eye further separate Pseudobarbus senticeps from Pseudobarbus afer s.s. which possesses simple short barbels which do not reach the vertical through the posterior margin of the eye. Pseudobarbus afer s.s differs from Pseudobarbus swartzi sp. n. by possession of fewer scale rows along the lateral line (29–35, mode 32 vs 34–37, mode 36 in Pseudobarbus swartzi), fewer scales around the caudal peduncle (12–16, mode 12 vs 13–17, mode 16 in Pseudobarbus swartzi) and a distinct mesh or net-like pigmentation pattern on latero-ventral scales. PMID:28331412

  2. Morphology of the jaw, suspensorial, and opercle musculature of Beloniformes and related species (Teleostei: Acanthopterygii), with a special reference to the m. adductor mandibulae complex

    PubMed Central

    2015-01-01

    The taxon Beloniformes represents a heterogeneous group of teleost fishes that show an extraordinary diversity of jaw morphology. I present new anatomical descriptions of the jaw musculature in six selected beloniforms and four closely related species. A reduction of the external jaw adductor (A1) and a changed morphology of the intramandibular musculature were found in many Beloniformes. This might be correlated with the progressively reduced mobility of the upper and lower jaw bones. The needlefishes and sauries, which are characterised by extremely elongated and stiffened jaws, show several derived characters, which in combination enable the capture of fish at high velocity. The ricefishes are characterised by several derived and many plesiomorphic characters that make broad scale comparisons difficult. Soft tissue characters are highly diverse among hemiramphids and flying fishes reflecting the uncertainty about their phylogenetic position and interrelationship. The morphological findings presented herein may help to interpret future phylogenetic analyses using cranial musculature in Beloniformes. PMID:25755920

  3. Leis' conundrum: homology of the clavus of the ocean sunfishes. 1. Ontogeny of the median fins and axial skeleton of Monotrete leiurus (Teleostei, Tetraodontiformes, Tetraodontidae).

    PubMed

    Britz, Ralf; Johnson, G David

    2005-10-01

    We describe the ontogeny of the axial skeleton and median fins of the Southeast Asian freshwater puffer Monotrete leiurus, based on a reared developmental series. Most elements of the axial skeleton in M. leiurus arise in membrane bone. Only the base of the anterior three neural arches, the base of the hemal arches of the third preural centrum, the neural and hemal arches and spines of the second preural centrum, the parhypural, the two hypural plates, and the single epural are preformed in cartilage. In contrast to most teleosts, the proximal-middle radials of the dorsal and anal fins are upright and symmetrical and their distal tips coalesce during development to form a deep band of cartilage, from which the spherical distal radials are spatially separated.

  4. Leis' conundrum: homology of the clavus of the ocean sunfishes. 2. Ontogeny of the median fins and axial skeleton of Ranzania laevis (Teleostei, Tetraodontiformes, Molidae).

    PubMed

    Johnson, G David; Britz, Ralf

    2005-10-01

    One of the most conspicuous characters of the ocean sunfishes, family Molidae, is the punctuation of the body by a deep, abbreviated, caudal fin-like structure extending vertically between the posterior ends of the dorsal and anal fins, termed the clavus by Fraser Brunner. Homology of the clavus has been a matter of debate since the first studies on molid anatomy in the early 1800s. Two hypotheses have been proposed: 1) It is a highly modified caudal fin; 2) It is formed by highly modified elements of the dorsal and anal fins. To resolve this homology issue, we studied the ontogeny of the molid vertebral column and median fins and compared it to that of a less morphologically derived gymnodont (see Part 1 of this study), a member of the family Tetraodontidae. We show that in molids the chorda never flexes during development, that the claval rays form from the posterior ends of the dorsal and anal fins toward the middle, thus closing the gap inward, and that elements of the molid clavus have an identical development and composition as the proximal-middle and distal radials of the regular dorsal and anal fins. We thus conclude that the molid clavus is unequivocally formed by modified elements of the dorsal and anal fin and that the caudal fin is lost in molids.

  5. Four new species of Cichlidogyrus (Monogenea: Ancyrocephalidae), gill parasites of Tilapia cabrae (Teleostei: Cichlidae), with discussion on relative length of haptoral sclerites.

    PubMed

    Pariselle, Antoine; Euzet, Louis

    2003-09-01

    Tilapia cabrae Boulenger, 1899, a cichlid fish from coastal lowlands of the Republic of Congo (Africa), was examined for gill parasites. Four new species of the Monogenea were found, all belonging to Cichlidogyrus (Ancyrocephalidae): C. berradae sp. n., C. revesati sp. n., C. legendrei sp. n., and C. lemoallei sp. n. A possible relationship between the relative size of haptoral sclerites (i.e., uncinuli compared to gripi) and microhabitat selection in the studied host-parasite model is discussed.

  6. Allozyme differentiation of two populations of the genus Neoplecostomus Eigenmann & Eigenmann, 1888 (Teleostei, Loricariidae) from the upper Paraná River basin, Brazil

    PubMed Central

    Reusing, Ana Flávia; Renesto, Erasmo; Roxo, Fábio F.; Zawadzki, Cláudio H.

    2011-01-01

    Allozyme electrophoresis was used to examine 12 enzymatic systems in two populations of the genus Neoplecostomus from the Paraná River basin. Samples of Neoplecostomus sp. 1 were collected in Paraitinguinha stream of the Tietê River basin, in the municipality of Salesópolis, São Paulo State, and those of Neoplecostomus sp. 2 from São Domingos stream of the Rio Grande River basin, in the municipality of Muzambinho, Minas Gerais State. The genetic variability of the two populations was estimated by Nei’s expected heterozygosity and was considered lower than average for populations of freshwater fish. The proportion of polymorphic loci was low (only 5.26% for the locus Idh). The low frequency of heterozygosity for both populations revealed a high fixation of alleles for each locus. Homozygote excess was observed in both populations. The values of Nei’s genetic identity and the presence of loci with different allele frequencies in both populations may imply that the two populations belong to different species. The genetic variability between populations was compared to other data for loricariids. PMID:21931525

  7. A new genus and species of blind sleeper (Teleostei: Eleotridae) from Oaxaca, Mexico: First obligate cave gobiiform in the Western Hemisphere

    USGS Publications Warehouse

    Walsh, Stephen J.; Chakrabarty, Prosanta

    2016-01-01

    Caecieleotris morrisi, new genus and species of sleeper (family Eleotridae), is described from a submerged freshwater cave in a karst region of the northern portion of the State of Oaxaca, Mexico, Río Papaloapan drainage, Gulf of Mexico basin. The new species represents the first cave-adapted sleeper known from the Western Hemisphere and is one of only 13 stygobitic gobiiforms known worldwide, with all others limited in distribution to the Indo-Pacific region. The new taxon represents a third independent evolution of a hypogean lifestyle in sleepers, the others being two species ofOxyeleotris (O. caeca and O. colasi) from New Guinea and a single species, Bostrychus microphthalmus, from Sulawesi. Caecieleotris morrisi, new species, is distinguished from epigean eleotrids of the Western Atlantic in lacking functional eyes and body pigmentation, as well as having other troglomorphic features. It shares convergent aspects of morphology with cave-dwelling species of Oxyeleotris and B. microphthalmus but differs from those taxa in lacking cephalic pores and head squamation, among other characters. Description of C. morrisi, new species, brings the total number of eleotrid species known from Mexico to 12. Seven of these, including the new species, occur on the Atlantic Slope.

  8. A new species of Neobathyclupea from the northern Indian Ocean with comments on N. malayana (Teleostei, Perciformes, Bathyclupeidae).

    PubMed

    Prokofiev, Artem M; Gon, Ofer; Psomadakis, Peter N

    2016-12-19

    A new species of Neobathyclupea is described from two specimens collected off Myanmar and off Socotra Island. The new species is most similar to N. malayana, but differs from it and other congeners in having jet-black coloured fins, larger pseudobranch, dorsal-pterygiophore pattern and some body proportions. Neobathyclupea malayana is re-diagnosed. Individual variations in armament of the preopercle and in the dorsal-pterygiophore patterns within Bathyclupeidae are discussed.

  9. Multilocus phylogeny of Crenicichla (Teleostei: Cichlidae), with biogeography of the C. lacustris group: species flocks as a model for sympatric speciation in rivers.

    PubMed

    Piálek, Lubomír; Ríčan, Oldřich; Casciotta, Jorge; Almirón, Adriana; Zrzavý, Jan

    2012-01-01

    First multilocus analysis of the largest Neotropical cichlid genus Crenicichla combining mitochondrial (cytb, ND2, 16S) and nuclear (S7 intron 1) genes and comprising 602 sequences of 169 specimens yields a robust phylogenetic hypothesis. The best marker in the combined analysis is the ND2 gene which contributes throughout the whole range of hierarchical levels in the tree and shows weak effects of saturation at the 3rd codon position. The 16S locus exerts almost no influence on the inferred phylogeny. The nuclear S7 intron 1 resolves mainly deeper nodes. Crenicichla is split into two main clades: (1) Teleocichla, the Crenicichla wallacii group, and the Crenicichla lugubris-Crenicichla saxatilis groups ("the TWLuS clade"); (2) the Crenicichla reticulata group and the Crenicichla lacustris group-Crenicichla macrophthalma ("the RMLa clade"). Our study confirms the monophyly of the C. lacustris species group with very high support. The biogeographic reconstruction of the C. lacustris group using dispersal-vicariance analysis underlines the importance of ancient barriers between the middle and upper Paraná River (the Guaíra Falls) and between the middle and upper Uruguay River (the Moconá Falls). Our phylogeny recovers two endemic species flocks within the C. lacustris group, the Crenicichla missioneira species flock and the herein discovered Crenicichla mandelburgeri species flock from the Uruguay and Paraná/Iguazú Rivers, respectively. We discuss putative sympatric diversification of trophic traits (morphology of jaws and lips, dentition) and propose these species flocks as models for studying sympatric speciation in complex riverine systems. The possible role of hybridization as a mechanism of speciation is mentioned with a recorded example (Crenicichla scottii).

  10. Omanicotyle heterospina n. gen. et n. comb. (Monogenea: Microcotylidae) from the gills of Argyrops spinifer (Forsskål) (Teleostei: Sparidae) from the Sea of Oman

    PubMed Central

    2013-01-01

    Background The Sultanate of Oman’s aquaculture industry is expanding with an on-going assessment of potential new fish species for culture. The king soldier bream, Argyrops spinifer (Forsskål) (Sparidae), is one such species that is under consideration. During a routine health assessment of specimens caught in the Sea of Oman throughout the period November 2009 to March 2011, a number of gill polyopisthocotylean monogeneans were recovered. Methods A subsequent study of the monogeneans using a range of morphology-based approaches indicated that these were Bivagina heterospina Mamaev et Parukhin, 1974. In the absence of pre-existing molecular data, an expanded description of this species is provided, including a differential diagnosis with other species and genera belonging to the subfamily Microcotylinae Monticelli, 1892 with the subsequent movement of this species to a new genus to accommodate it. Results The polyopisthocotyleans collected from the gills of A. spinifer appear to be unique within the family Microcotylidae Taschenberg, 1879 in that, morphologically, they possess a pair of large, muscular vaginae each armed with a full crown of 16–18 robust spines and a unique dorsal region of folded tegument, which permits their discrimination from species of Bivagina Yamaguti, 1963. Sequencing of the SSU rDNA (complete 1968 bp) and LSU rDNA (partial 949 bp) places the specimens collected during this study within the subfamily Microcotylinae, but the LSU rDNA sequence differs from Bivagina and also from other microcotylid genera. Morphological features of B. heterospina sensu Mamaev et Parukhin, 1974 and the specimens collected from the current study are consistent with one another and represent a single species. The vaginal armature of these worms is unique and differs from all other genera within the Microcotylinae, including Bivagina, and its movement to Omanicotyle n. gen. to accommodate this species is proposed. Conclusions A new genus, Omanicotyle n. gen., is erected to accommodate Omanicotyle [Bivagina] heterospina n. comb. which represents the first monogenean to be described from Omani marine waters. Given the pathogenic potential of microcotylids on captive held fish stocks, a full assessment of Omanicotyle heterospina n. gen. et n. comb. is now required before large-scale production commences. PMID:23758894

  11. Reassessment and Relationships of †Scutatuspinosus itapagipensis (Teleostei, Clupeomorpha, †Ellimmichthyiformes) from the Neocomian of Recôncavo Basin, Northeastern Brazil.

    PubMed

    Figueiredo, Francisco J DE; Ribeiro, Douglas R M

    2017-02-06

    Clupeomorphs are found in many assemblages of the northeastern Brazil, whose ages range from the Neocomian to Paleogene. Ten species were described. Among them †Scutatuspinosus itapagipensis, a torpedo-like fish found in shales of the Marfim Formation from Bahia, remains poorly known. At first it was positioned within †Scutatuspinosinae and indicated as closely related to †Diplomystus. Diagnoses for the subfamily and genus were based on certain characters masking relationships. Recently it was placed in †Ellimmichthyiformes, but its systematic position remains controversial. We furnish additional data and restorations together with a parsimony analysis with TNT program, using 60 unordered and unweighted characters from selected species of 13 genera. Our analysis produced 12 trees with 158 steps, a consistency index (CI) of 0.44 and retention index (RI) of 0.52. Low support indices still indicate insufficient data for many taxa and uncertain status for clades. According to the majority rule consensus, †Scutatuspinosus itapagipensis is placed within a "†paraclupeine" group with †Ezkutuberezi carmenae, †Ellimma branneri, †Ellimmichthys longicostatus, and †Paraclupea chetunguensis. Its minimum age and position among †paraclupeids indicate an early history of the group older than it was thought to be, supporting a biogeographical hypothesis based on generalized track from China to northeastern Brazil during the Lower Cretaceous.

  12. Genome-wide SNPs resolve a key conflict between sequence and allozyme data to confirm another threatened candidate species of river blackfishes (Teleostei: Percichthyidae: Gadopsis).

    PubMed

    Unmack, Peter J; Sandoval-Castillo, Jonathan; Hammer, Michael P; Adams, Mark; Raadik, Tarmo A; Beheregaray, Luciano B

    2017-04-01

    Conflicting results from different molecular datasets have long confounded our ability to characterise species boundaries. Here we use genome-wide SNP data and an expanded allozyme dataset to resolve conflicting systematic hypotheses on an enigmatic group of fishes (Gadopsis, river blackfishes, Percichthyidae) restricted to southeastern Australia. Previous work based on three sets of molecular markers: mtDNA, nuclear intron DNA and 51 allozyme loci was unable to clearly resolve the status of a putative fifth candidate species (SWV) within Gadopsis marmoratus. Resolving the taxonomic status of candidate species SWV is particularly critical as based on IUCN criteria this taxon would be considered Critically Endangered. After all filtering steps we retained a subset of 10,862 putatively unlinked SNP loci for population genetic and phylogenomic analyses. Analyses of SNP loci based on maximum likelihood, fastSTRUCTURE and DAPC were all consistent with the previous and updated allozyme results supporting the validity of the candidate Gadopsis species SWV. Immediate conservation actions should focus on preventing take by anglers, protection of water resources to sustain perennial reaches and drought refuge pools, and aquatic and riparian habitat protection and improvement. In addition, a formal morphological taxonomic review of the genus Gadopsis is urgently required.

  13. Taste bud form and distribution on lips and in the oropharyngeal cavity of cardinal fish species (Apogonidae, Teleostei), with remarks on their dentition.

    PubMed

    Fishelson, Lev; Delarea, Yakob; Zverdling, Adi

    2004-03-01

    The oral dentition and type and number of taste buds (TB) on the lips and in the oropharyngeal cavity were compared by means of SEM in 11 species of cardinal fishes (Apogonidae) belonging to five genera. The occurrence of a dense cover of skin papillae on the lips of some species (e.g., Apogon frenatus), as well as differences in structure of vomer, tongue, and palatinum, expose additional morphological characters important for clarification of the taxonomy of this group of fishes. Differences are also revealed in the type of dentition, such as on the vomer and epi-hypopharyngeal bones. Strong and dense dentition of the anterior part of the oral cavity and a high number of TB on this site in species feeding on larger prey (e.g., Cheilodipterus spp) is compared to the relatively feeble jaw armor and richness of TB on the more pharyngeal site in species feeding on smaller prey (e.g., Apogon angustatus, A. frenatus). In addition to the three types of TB (Types I-III) previously described from various teleost fish, a fourth type (Type IV), comprising very small buds, was found in some cardinal fish (Apogon angustatus, A. frenatus). The various TB are distributed from the lips to the pharyngeal bones, on the breathing valves, tongue, palatinum, and pharyngeal bones; their number and type on the various sites differ in the different species. In all species studied the Types I and II TB, elevated above the surrounding epithelium, dominated the lips and anterior part of mouth, while Types III and IV, which end apically at the level with the epithelium, dominated the more posterior pharyngeal region. The highest number of TB, around 24,600, were found in Fowleria variegata, a typical nocturnal species, and the lowest in the diurnal and crepuscular Apogon cyanosoma (1,660) and Cheilodipterus quinquestriatus (2,400). Differences are also revealed in the type of dentition, such as on the vomer and epi-hypopharyngeal bones. The number of TB increased with growth of the fishes. The differences in the total number of TB and their distribution in the oropharyngeal cavity in the various species indicates possible different mechanisms of foraging and food-recognition.

  14. Genetic heterogeneity reveals on-going speciation and cryptic taxonomic diversity of stream-dwelling gudgeons (Teleostei, Cyprinidae) in the middle Danubian hydrosystem (Hungary).

    PubMed

    Takács, Péter; Bihari, Péter; Erős, Tibor; Specziár, András; Szivák, Ildikó; Bíró, Péter; Csoma, Eszter

    2014-01-01

    Although stream-dwelling gudgeons (Cyprinidae, genus: Gobio) are widespread in Central Europe, the taxonomy of this group and the distribution of its species are still unexplored in detail. The aims of our study are to ascertain taxonomic composition and distribution of the former Gobio gobio superspecies in the inner area of the Carpathian Basin. Since the presence of cryptic species is suspected in this area, we examined the taxonomic and phylogenetic relationships of Central European Gobio taxa by sequencing the mitochondrial DNA control region (mtCR). Additionally, we characterized the genetic structure of 27 stream-dwelling gudgeon populations of this area by Amplified Fragment Length Polymorphism (AFLP). Results of mtCR analysis proved the presence of three species already known as G. obtusirostris (dominant in NW-Hungary), G. gobio (sporadic) and G. carpathicus (sporadic). Additionally, the analysis revealed the existence of one doubtful taxon, G. sp1 (dominant in NE-Hungary), and a new isolated haplogroup (dominant in SW-Hungary). Although Network analysis showed significant detachment among haplogroups, their genetic distances were quite small. Therefore Bayesian phylogenetic analysis showed weak nodal support for the branching pattern both for newly described haplotypes, and for the already accepted species. AFLP data showed distinct population structure and a clear pattern of isolation was revealed by distance of stocks. At the same time, level of separation was not affected by the altitudinal position of sites. Moreover we found three major clusters of populations which were separated according to hydrographic regions, and corresponded to the findings of mtCR analysis. Our results suggest the on-going speciation of gudgeons in the Carpathian Basin, however the separation of haplogroups seems to only be an intermediate phase. The discovered natural pattern seems to be only slightly influenced by anthropogenic impacts. Additionally our results put into question the suitability of the recently accepted within Gobio genus taxonomy.

  15. Ice age cloning--comparison of the Quaternary evolutionary histories of sexual and clonal forms of spiny loaches (Cobitis; Teleostei) using the analysis of mitochondrial DNA variation.

    PubMed

    Janko, K; Culling, M A; Ráb, P; Kotlík, P

    2005-09-01

    Recent advances in population history reconstruction offered a powerful tool for comparisons of the abilities of sexual and clonal forms to respond to Quaternary climatic oscillations, ultimately leading to inferences about the advantages and disadvantages of a given mode of reproduction. We reconstructed the Quaternary historical biogeography of the sexual parental species and clonal hybrid lineages within the Europe-wide hybrid complex of Cobitis spiny loaches. Cobitis elongatoides and Cobitis taenia recolonizing Europe from separated refuges met in central Europe and the Pontic region giving rise to hybrid lineages during the Holocene. Cobitis elongatoides due to its long-term reproductive contact with the remaining parental species of the complex--C. tanaitica and C. spec.--gave rise to two clonal hybrid lineages probably during the last interglacial or even earlier, which survived the Würmian glaciation with C. elongatoides. These lineages followed C. elongatoides postglacial expansion and probably decreased its dispersal rate. Our data indicate the frequent origins of asexuality irrespective of the parental populations involved and the comparable dispersal potential of diploid and triploid lineages.

  16. Hair Cell Heterogeneity in the Goldfish Saccule

    NASA Technical Reports Server (NTRS)

    Saidel, William M.; Lanford, Pamela J.; Yan, Hong Y.; Popper, Arthur N.

    1995-01-01

    A set of cytological studies performed in the utricle and saccule of Astronotus ocellatus (Teleostei, Percomorphi, Cichlidae) identified two basic types of hair cells and others with some intermediate characteristics. This paper reports on applying the same techniques to the saccule of Carassius auratus (Teleostei, Otophysi, Cyprinidae) and demonstrates similar types of hair cells to those found in Astronotus. Since Carassius and Astronous are species of extreme taxonomic distance within the Euteteostei, two classes of mechanoreceptive hair cells are likely to represent the primitive condition for sensory receptors in the euteleost inner ear and perhaps in all bony fish ears.

  17. [Some attributes of community structure of fishes in Laguna Grande de Obispo, Golfo Cariaco, Sucre State, Venezuela].

    PubMed

    De Grado, A A; Bashirullah, A

    2001-01-01

    Species composition, relative abundance, diversity and community structure of fishes were studied from monthly sampling during December 1995 to November 1996 in the Laguna Grande de Obispo, Gulf of Cariaco, Sucre State, Venezuela. Sampling were realised in 3 stations inside the lagoon with a small beach seine and the other 4 stations with a large beach seine. Seventy four species belonging to 33 families and 68 genera were identified of which 8 species dominated, constituting 90.43% of total catch. Mugil curema, Xenomelaniris brasiliensis, Opistonema oglinum, Atherinomorus stipes and Anchoa hepsetus were present in high abundance in the biomass. M. curema dominated the catch with large seine while X. brasiliensis, M. curema and Eucinostomus argenteus dominated the catch with small seine. Species diversity (H') ranged from 2.968-4.607 bits/ind and species richness of Margalef from 2.752-7.464. An inverse analysis realized on catches by small seine and based on nodal constancy and fidelity allowed to define a pattern of spatial distribution of 9 groups containing 1 to 11 species on the basis their abundance, frequency of appearance and ecological characteristics of each area. An analysis of correlation showed that the salinity, dissolved O2 and precipitation did not show any significant correlation with the ecological parameters studied but existed significant correlation with average surface water temperature (p < 0.05), number of species (S), individuals (N), diversity (H') and species richness (D). The positive correlation was found with surface temperature but no relationship with relative dominance (D1 and D2). The CPUE in biomass did not show any significant association with temperature.

  18. Gonadotropin-dependent oocyte maturational competence requires activation of the protein kinase A pathway and synthesis of RNA and protein in ovarian follicles of Nibe, Nibea mitsukurii (Teleostei, Sciaenidae)

    USGS Publications Warehouse

    Yoshizaki, G.; Shusa, M.; Takeuchi, T.; Patino, R.

    2002-01-01

    Luteinizing hormone- (LH)-dependent ovarian follicle maturation has been recently described in two stages for teleost fishes. The oocyte's ability to respond to the steroidal maturation-inducing hormone (MIH), also known as oocyte maturational competence (OMC), is acquired during the first stage; whereas the MIH-dependent resumption of meiosis occurs during the second stage. However, studies directly addressing OMC have been performed with a limited number of species and therefore the general relevance of the two-stage model and its mechanisms remain uncertain. In this study, we examined the hormonal regulation of OMC and its basic transduction mechanisms in ovarian follicles of the sciaenid teleost, Nibe (Nibea mitsukurii). Exposure to MIH [17,20??-dihydroxy-4-pregnen-3-one or 17,20??,21-trihydroxy-4-pregnen-3-one] stimulated germinal vesicle breakdown (index of meiotic resumption) in full-grown follicles primed with human chorionic gonadotropin (HCG, an LH-like gonadotropin) but not in those pre-cultured in plain incubation medium. The induction of OMC by HCG was mimicked by protein kinase A (PKA) activators (forskolin and dibutyryl cyclic AMP), and blocked by specific inhibitors of PKA (H89 and H8) as well as inhibitors of RNA (actinomycin D) and protein (cycloheximide) synthesis. Forskolin-induced OMC was also inhibited by actinomycin D and cycloheximide. A strong activator of protein kinase C, PMA, inhibited HCG-dependent OMC. In conclusion, OMC in Nibe ovarian follicles is gonadotropin-dependent and requires activation of the PKA pathway followed by gene transcription and translation events. These observations are consistent with the two-stage model of ovarian follicle maturation proposed for other teleosts, and suggest that Nibe can be used as new model species for mechanistic studies of ovarian follicle differentiation and maturation in fishes.

  19. Population Structure, Genetic Diversity, Effective Population Size, Demographic History and Regional Connectivity Patterns of the Endangered Dusky Grouper, Epinephelus marginatus (Teleostei: Serranidae), within Malta’s Fisheries Management Zone

    PubMed Central

    Vella, Adriana

    2016-01-01

    The objective of this study is to describe the genetic population structure and demographic history of the endangered marine fish, Epinephelus marginatus, within Malta’s Fisheries Management Zone for the purpose of localised conservation planning. Epinephelus marginatus is a long-lived, sedentary, reef-associated protogynous hermaphrodite with high commercial and recreational value that is at risk of extinction throughout its global distribution. Based on global trends, population substructuring and gaps in local knowledge this has led to an increased interest in evaluation of local stock. Assessment of Maltese demography was based on historical and contemporary catch landings data whilst genetic population structure and regional connectivity patterns were evaluated by examining 175 individuals collected within the central Mediterranean region between 2002 and 2009 using 14 nuclear microsatellite loci. Demographic stock assessment of Maltese E. marginatus’ revealed a 99% decline in catch landings between 1947 and 2009 within the Fisheries Management Zone. A contemporary modest mean size was observed, 3 ± 3 kg, where approximately 17% of the population was juvenile, 68% female/sex-changing and 15% were male with a male-to-female sex ratio of 1:5. Genetic analysis describes the overall population of E. marginatus’ within the Fisheries Management Zone as decreasing in size (ƟH = 2.2), which has gone through a significant size reduction in the past (M = 0.41) and consequently shows signs of moderate inbreeding (FIS = 0.10, p < 0.001) with an estimated effective population size of 130 individuals. Results of spatially explicit Bayesian genetic cluster analysis detected two geographically distinct subpopulations within Malta’s Fisheries Management Zone and that they are connected to a larger network of E. marginatus’ within the Sicily Channel. Results suggest conservation management should be designed to reflect E. marginatus’ within Malta’s Fisheries Management Zone as two management units. PMID:27463811

  20. Relationships of †Codoichthys carnavalii Santos, 1994 (Teleostei, Clupeomorpha, †Ellimmichthyiformes) from the Late Aptian of São Luís-Grajaú Basin, NE Brazil.

    PubMed

    Figueiredo, Francisco J DE; Ribeiro, Douglas R M

    2016-09-01

    †Codoichthys carnavalii is a clupeomorph fish only found in calcareous concretions of Codó Formation, State of Maranhão. It is known based on three specimens housed in the paleontological collection of the Museu de Ciências da Terra of Departamento Nacional da Produção Mineral, Rio de Janeiro. It was omitted in most of recent cladistic analyses about clupeomorphs. We revisited its anatomy furnishing new data and additional restorations. Furthermore we explored the relationships of †Codoichthys with the computer program TNT based on a matrix with 30 taxa and 60 unordered and unweight characters. Elops was used to root the tree. The strict consensus was obtained from three shortest trees (L=181; CI=0.387; RI=0.632). The monophyly of †Ellimmichthyiformes is supported by a sigmoid cleithrum and an uniquely derived predorsal scute series. Most of subgroups showed low support indices. †Sorbinichthyidae and †Horseshoeichthys appear in the most basal position, and not closely related to †Armigatus or †Diplomystus. A †Diplomystus clade is more advanced than †Armigatus and sister-group of remaining †ellimmichthyiforms. Within †Paraclupeidae, †Codoichthys is sister-group of remaining †paraclupeids (including †thorectichthyines and †paraclupeines). Within †Paraclupeinae, †Triplomystini includes a †Triplomystus clade, a sister group of †Rhombichthys plus †Tycheroichthys, and †Paraclupeini with †S. itapagipensis and all other †ellimmichthyiform taxa.

  1. Comment on "On Gonorynchus, Gonorhynchus, Gonorinchus, Gonorhinchus, and Gonorrhynchus, and some other names of labeonine fishes (Teleostei: Gonorhynchidae and Cyprinidae)" by Kottelat (2016).

    PubMed

    Ciccotto, Patrick J; Page, Lawrence M

    2017-01-26

    Kottelat (2016) noted that 'Gonorhynchus McClelland, 1838,' the name used for a South Asian cyprinid genus recognized by Yang et al. (2012) and revised by Ciccotto & Page (2016), does not exist or is a junior homonym of Gonorhynchus Cuvier, 1816. He further noted that Tariqilabeo Mirza & Saboohi, 1990 is the valid genus name for the species recognized in Gonorhynchus by Yang et al. (2012) and by Ciccotto & Page (2016). Kottelat also rejected the placement of Epalzeorhynchus bicornis Wu, 1977 in this genus by Yang et al. (2012), instead placing it in the monotypic Akrokolioplax Zhang & Kottelat, 2006, and questioned the validity of the designation of the neotype of Cyprinus latius Hamilton, 1822 by Ciccotto & Page (2016). While we are in agreement with the validity of Tariqilabeo, we disagree with the use of Akrokolioplax and defend the designation of the neotype for C. latius.

  2. Deep-sea bigscales, pricklefishes, gibberfishes and whalefishes (Teleostei: Stephanoberycoidei) off Brazil: new records, range extensions for the south-western Atlantic Ocean and remarks on the taxonomy of Poromitra.

    PubMed

    Mincarone, M M; Di Dario, F; Costa, P A S

    2014-11-01

    The Stephanoberycoidei includes 23 genera and c. 94 species of deep-sea teleosts commonly known as bigscales, pricklefishes, gibberfishes and whalefishes. Stephanoberycoidei is one of the least known groups of deep-sea fishes, in spite of their apparent relative abundance in meso and bathypelagic depths. Nine species of the Stephanoberycoidei are reported here for the first time in Brazilian waters, and most of them represent new range extensions for the south-western Atlantic Ocean. Those species are Melamphaes polylepis, Melamphaes typhlops, Poromitra sp. and Scopeloberyx robustus (Melamphaidae), Acanthochaenus luetkenii and Stephanoberyx monae (Stephanoberycidae), Rondeletia bicolor and Rondeletia loricata (Rondeletiidae) and Gyrinomimus sp. (Cetomimidae). Occurrences of the pricklefish Scopelogadus mizolepis (Melamphaidae), the gibberfish Gibberichthys pumilus (Gibberichthyidae) and the velvet whalefish Barbourisia rufa (Barbourisiidae) are confirmed in the Brazilian exclusive economic zone, but previously published records of Poromitra capito and Melamphaes simus (Melamphaidae) in the region most likely represent misidentifications. Validities of the recently described Poromitra kukuevi and Poromitra indooceanica are discussed in light of new specimens of the genus collected in the south-western Atlantic Ocean. An identification key for the 13 species of Stephanoberycoidei reported off Brazil is also provided.

  3. Ligophorus species (Monogenea: Ancyrocephalidae) from Mugil cephalus (Teleostei: Mugilidae) off Morocco with the description of a new species and remarks about the use of Ligophorus spp. as biological markers of host populations.

    PubMed

    El Hafidi, Fouzia; Rkhami, Ouafae Berrada; de Buron, Isaure; Durand, Jean-Dominique; Pariselle, Antoine

    2013-11-01

    Gill monogenean species of Ligophorus Euzet et Suriano, 1977 were studied from the teleost Mugil cephalus Linneaus (Mugilidae) from the Mediterranean and Atlantic coasts of Morocco. We report the presence of L. mediterraneus from both the Mediterranean and Atlantic coast and L. cephali and L. maroccanus sp. n. from the Atlantic coast only. The latter species, which is described herein as new, resembles L. guanduensis but differs from this species mainly in having a shorter penis compared to the accessory piece, a proportionally longer extremity of the accessory piece and a less developed heel. The utility of Ligophorus spp. as markers of cryptic species of the complex M. cephalus is discussed in the context of species diversity and geographical distribution of these monogeneans on this host around the world. Presence of different species of Ligophorus on M. cephalus sensu stricto from the Atlantic and Mediterranean coast of Morocco demonstrates the usefulness of these species as fine resolution markers of genetic populations of their host, which are known to inhabit those coasts.

  4. Lamellodiscus (Monogenea: Diplectanidae) parasites of Dentex macrophthalmus (Teleostei: Sparidae) from the North Atlantic coast of Africa, with a redescription of L. dentexi Aljoshkina, 1984, and description of three new species.

    PubMed

    Diamanka, Arfang; Neifar, Lassâd; Pariselle, Antoine; Euzet, Louis

    2011-03-01

    Lamellodiscus dentexi Aljoshkina, 1984, a gill parasite of Dentex macrophthalmus (Bloch), is redescribed based on new material from the northwest coast of Africa (Senegal and Morocco). Three new species of Lamellodiscus Johnston et Tiegs, 1922 from D. macrophthalmus are described, Lamellodiscus toguebayei sp. n., L. vicinus sp. n., and L. triacies sp. n., all belonging to the "ignoratus" group. They can be distinguished from all other species of this group by the size and shape of male copulatory organ and sclerotised parts of the haptor. Considering the peculiar morphology of the male copulatory organ (long and thin tube) we propose to put together L. dentexi, L. virgula Euzet et Oliver, 1967 and L. obeliae Oliver, 1973 to form the "elongatus" type within the "elegans" group.

  5. Effects of orally administered chemotherapeutics (quinine, salinomycin) against Henneguya sp. Thelohán, 1892 (Myxozoa: Myxobolidae), a gill parasite in the tapir fish Gnathonemus petersii Günther, 1862 (Teleostei).

    PubMed

    Dohle, Angelika; Schmahl, Günter; Raether, Wolfgang; Schmidt, Hartmut; Ritter, Günter

    2002-09-01

    When given orally, quinine or salinomycin cause irreversible damage to the plasmodial developmental stages of Henneguya sp., a gill parasite in the tapir fish Gnathonemus petersii. Naturally infected tapir fish measured 75-169 mm in total length and their total weight ranged over 4.3-11.7 g. The fish bore 7-77 plasmodia in their gill arches. Medicinal food containing either quinine (5 g/1000 g food) or salinomycin (0.075 g/1000 g food) was given once a day to naturally infected fish in a food chain via water fleas ( Daphnia spp) for a period of 3, 6, or 9 days. From the monitored feeding of the tapir fish and weight determinations of the water fleas, it was calculated that gross uptake was 18.5 micro g/kg body weight fish daily for pure salinomycin and was 1.25 mg/kg body weight daily for quinine. After the end of the experiments, the fish were sacrificed and the plasmodia were carefully prepared from the gill arches and processed for transmission electron microscopy. As seen by ultrastructure investigations, for both substances the grade of damage in the parasites correlated positively with the period of application. When quinine was given for a 3-day period, the trophozoite ecto- and endoplasm exerted numerous vacuoles, caused by the drug, and the presporogonous and the pansporoblastic stages were malformed. Following a 6-day period, numerous abortive polar capsules were found in the trophozoite cytoplasm. To a large extent, the limiting membranes of the polaroblasts and valvogenic cells were destroyed. In addition, deep clefts between the polaroblasts, the valvogenic cells and between the two sporoblasts were observed. Following a 9-day treatment, all damage increased and, in addition, generative cells and two-cell stages were no longer detectable. As a first sign for the effects of salinomycin, following a 3-day treatment, a shrinking of the whole plasmodia occurred and the sutures in the pansporoblasts were enlarged. The polar capsules were malformed and the zonar structures of the polar filament were no longer detectable. The sporoplasmosomes were more electron-pale than those of the control samples. After a 9-day treatment, the pansporoblasts were completely destroyed. Under the experimental conditions chosen, both compounds were very well tolerated by the fishes.

  6. Descriptions of four species of grenadier fishes of the genera Hymenocephalus and Hymenogadus (Teleostei, Gadiformes, Macrouridae) from the New Zealand region and Tasman Sea, including two new species of Hymenocephalus.

    PubMed

    McMillan, Peter; Iwamoto, Tomio

    2014-08-21

    Two new species of Hymenocephalus are described from the New Zealand region and Tasman Sea. Hymenocephalus fuscus sp. n. has 11-12 pelvic fin rays, is darkly pigmented, with enlarged bony ridges on the dorsal aspects of head, lacks a chin barbel, has few (16-19) gill rakers on inner side of first arch and is similar to other species in the H. aterrimus species group. Hymenocephalus maculicaudus sp. n. has 8 pelvic fin rays, a mid-lateral line of melanophores on body and tail that extends about a head length posterior to anal fin origin, a short (7-16 % HL) chin barbel and is similar to other species in the H. megalops species group. Hymenocephalus nascens has 12-14 pelvic fin rays, lacks a chin barbel, has a mid-lateral stripe of silvery (fresh) or brownish (preserved) pigment running along trunk and tail. Hymenogadus gracilis has a serrated (weak, near tip) first dorsal fin spine, 7-9 pelvic fin rays, long (20-30% HL) chin barbel, and one row of enlarged melanophores along lateral mid-line of the tail. Hymenocephalus nascens and Hymenogadus gracilis are recorded for the first time from the New Zealand region. A key to the known New Zealand species of Hymenocephalus and Hymenogadus is provided. 

  7. The gynogenetic reproduction of diploid and triploid hybrid spined loaches (Cobitis: Teleostei), and their ability to establish successful clonal lineages--on the evolution of polyploidy in asexual vertebrates.

    PubMed

    Janko, Karel; Bohlen, Jörg; Lamatsch, Dunja; Flajshans, Martin; Epplen, Jörg T; Ráb, Petr; Kotlík, Petr; Slechtová, Vera

    2007-10-01

    Polyploidisation is assumed to have played a significant role in the evolution of hybrid asexual lineages. The virtual absence of natural asexual systems in which more than a single ploidy level successfully establishes successful independent clonal lineages is generally explained by the strong effects of polyploidisation on fitness. Experimental crosses were made between diploid and triploid asexual Cobitis elongatoides x C. taenia hybrids (female) and both parental spined loach species (male). Genotyping of the progeny using allozymes and multilocus DNA fingerprinting, along with flow cytometric measurement of ploidy level, demonstrated the occurrence of gynogenetic reproduction in both female biotypes. The incorporation of the sperm genome occurred in some progeny, giving rise to a higher ploidy level, but the rate of polyploidisation differed significantly between the diploid and triploid females. These outcomes are consistent with the existence of developmental constraints on tetraploidy, which determine the rarity of tetraploids in natural populations. No cases of ploidy level reduction were observed. Since diploid and triploid hybrid populations occur where the lack of potential progenitor excludes the possibility of de novo origin, it is probable that both diploid and triploid females can establish successful clonal lineages. Spined loaches represent a unique example, among asexual vertebrates, where more than one ploidy level can establish persistent clonal lineages, which are reproductively independent of one another.

  8. Cytogenetic comparison between two allopatric populations of Astyanax altiparanae Garutti et Britski, 2000 (Teleostei, Characidae), with emphasis on the localization of 18S and 5S rDNA.

    PubMed

    Pacheco, Rosiley Berton; da Rosa, Renata; Giuliano-Caetano, Lucia; Júlio, Horácio Ferreira; Dias, Ana Lúcia

    2011-01-01

    Two populations of Astyanax altiparanae (Garutti & Britski, 2000) of the Água dos Patos stream/SP and lake Igapó/PR were analyzed. All individuals showed 2n = 50, however, different karyotypic formulae were observed. The population of the Água dos Patos stream showed 8m +24sm+6st+12a (NF=88) and the population of lake Igapó, 8m+28sm+4st+10a (NF=90). Nucleolus organizing regions (AgNORs) were observed in the terminal position on the short and long arm of different chromosomes of both populations, showing a variation from 3 to 4 chromosomes. Fluorescent in situ hybridization (FISH) using 18S rDNA probes revealed only one pair of chromosomes with fluorescent signals in the terminal site on the short arm in the Igapó lake population, while the population of Água dos Patos stream showed 4 fluorescence terminal signals, characterizing a system of simple and multiple NORs, respectively. 5S rDNA fluorescent signals were detected in the interstitial position of a pair of chromosomes in the two studied populations. Some AgNOR sites revealed to be GC-rich when stained with Chromomycin A3 (CMA3), however, AT positive regions were not observed. The data obtained show that, despite the conservation of the diploid number and location of 5S DNAr, differences in both the distribution of 18S rDNA and karyotypic formula among the populations were found, thus corroborating the existing data on chromosome variability in Astyanax altiparanae that can be significant for cytotaxonomy in this group.

  9. Dactylogyrids (Monogenoidea) parasitizing the gills of spinefoots (Teleostei: Siganidae): proposal of Glyphidohaptor n. gen., with two new species from the Great Barrier Reef, Australia, and G. plectocirra n. comb. from Ras Mohammed National Park, Egypt.

    PubMed

    Kritsky, Delane C; Galli, Paolo; Yang, Tingbao

    2007-02-01

    Nine species of Siganus (Perciformes: Siganidae) were examined for dactylogyrids (Monogenoidea) from the Red Sea, Egypt; the Great Barrier Reef, Australia; and the South China Sea, China. Species of Tetrancistrum were found on siganids from all 3 localities; Pseudohaliotrema spp. were restricted to siganids from the Great Barrier Reef; and species representing Glyphidohaptor n. gen. were found on siganids from the Red Sea and Great Barrier Reef. Siganus argenteus from the Red Sea and Siganus vulpinus from the Great Barrier Reef were negative for dactylogyrid parasites. Glyphidohaptor n. gen. is proposed for 3 species (2 species new to science) and the new species are described: Glyphidohaptor phractophallus n. sp. from Siganus fuscescens from the Great Barrier Reef; Glyphidohaptor sigani n. sp. from Siganus doliatus (type host), Siganus punctatus, Siganus corallinus, and Siganus lineatus from the Great Barrier Reef; and Glyphidohaptor plectocirra (Paperna, 1972) n. comb. (= Pseudohaliotrema plectocirra Paperna, 1972) from Siganus luridus and Siganus rivulatus from the Red Sea.

  10. Culture and behavior of selected estuarine fish and shellfish in aquaria receiving effluent water from a power plant

    SciTech Connect

    Carr, B.A.

    1981-01-01

    Sixteen species (2 molluscs, 2 crustaceans, and 12 fishes) were used as biological monitors in flow-through aquaria. The aquaria received effluent from Houston Lighting and Power Company's Cedar Bayou generating station located in Chambers County, Texas. Growth and survival of organisms were monitored in ambient and thermally regulated water (20, 25, and 30/sup 0/C). Behavior experiments were carried out with several of the monitor species, Cyprinodon variegatus, Mugil cephalus and Mugil curema. R. cuneata, C. virginica, L. xanthurus, M. undulatus, C. faber and M. cephalus were analyzed for heavy metals and pesticides and were evaluated according to current Food and Drug Administration (FDA) standards. All organisms were found to be within the established FDA tolerance levels and are therefore considered fit for human consumption. C. variegatus was tested at varius sex-ratios to determine whether a particular ratio could maximize the number of young produced. No statistically significant difference was found in the number of young produced; however, population density and sex-ratio significantly increased total adult mortality. The swimming and feeding behavior of M. cephalus and M. curema was observed and described. The number of food bites was significantly affected by the interactions of culture, species, and density. During polyculture situations there were significantly more food bites, long traverses and total traverses than in monoculture situations.

  11. A new species of Hemipera Nicoll, 1913 (Digenea: Derogenidae) from fishes of the intertidal rocky zone of Chile.

    PubMed

    Díaz, Pablo E; Muñoz, Gabriela; George-Nascimento, Mario

    2016-09-01

    A new species, Hemipera cribbi sp. nov., is described. This trematode was found in three intertidal fish species: Scartichthys viridis (Valenciennes) (Blenniidae), Gobiesox marmoratus Jenyns (Gobiesocidae) and Myxodes viridis Valenciennes (Clinidae) from the central and southern coast of Chile. Of 233 individuals of S. viridis from the central coast examined, 19 were infected. From the southern coast, nine individuals of S. viridis (one infected), five individuals of G. marmoratus (four infected), and 16 individuals of M. viridis (one fish infected) were examined. Hemipera cribbi sp. nov. is distinguished from the five other congeneric species mainly in the body size, being the smallest and narrowest species in the genus, reaching five times longer than wide. This is the first species of the genus described for the South Pacific Ocean off South America. ITS2 rDNA sequences of Hemipera cribbi sp. nov. from each host and locality were identified.

  12. A New Record for Occurrence of Symphodus bailloni (Osteichthyes: Perciformes: Labridae) in the Western Black Sea Coast of Turkey

    PubMed Central

    Göktürk, Didem; Karakulak, F. Saadet; Ünsal, Nuran; Kahraman, Abdullah E.

    2012-01-01

    The fish species Symphodus bailloni (Valenciennes, 1839) reported in the present study were collected between June 2010 and June 2011 from the western Black Sea coasts which were previously not recorded from the Black Sea coast of Turkey. A total of 717 specimens of S. bailloni were measured, ranging between 8.9 and 15.4 cm TL. Morphometrics, meristics, and diagnostic characteristics of the species are presented. PMID:22593703

  13. Habitat Preference, Dispersal, and Population Trends of Three Species of Invasive Asian Carps in Tributaries of the La Grange Reach of the Illinois River

    DTIC Science & Technology

    2012-07-01

    in the late 1960s and early 1970s for aquacultural purposes. Because of its voracious appetite for aquatic macrophytes, the phytophagous grass carp...molitrix, Valenciennes 1844) were introduced into the United States to help control plankton and algal blooms in aquaculture ponds (Kolar et al...form of flooded terrestrial plants (Figure 3, Table 3). Both Indian Creek and Wolf Creek had deeply incised channels with steep sides. The Indian

  14. The Jaw Adductor Muscle Complex in Teleostean Fishes: Evolution, Homologies and Revised Nomenclature (Osteichthyes: Actinopterygii)

    PubMed Central

    Datovo, Aléssio; Vari, Richard P.

    2013-01-01

    The infraclass Teleostei is a highly diversified group of bony fishes that encompasses 96% of all species of living fishes and almost half of extant vertebrates. Evolution of various morphological complexes in teleosts, particularly those involving soft anatomy, remains poorly understood. Notable among these problematic complexes is the adductor mandibulae, the muscle that provides the primary force for jaw adduction and mouth closure and whose architecture varies from a simple arrangement of two segments to an intricate complex of up to ten discrete subdivisions. The present study analyzed multiple morphological attributes of the adductor mandibulae in representatives of 53 of the 55 extant teleostean orders, as well as significant information from the literature in order to elucidate the homologies of the main subdivisions of this muscle. The traditional alphanumeric terminology applied to the four main divisions of the adductor mandibulae – A1, A2, A3, and Aω – patently fails to reflect homologous components of that muscle across the expanse of the Teleostei. Some features traditionally used as landmarks for identification of some divisions of the adductor mandibulae proved highly variable across the Teleostei; notably the insertion on the maxilla and the position of muscle components relative to the path of the ramus mandibularis trigeminus nerve. The evolutionary model of gain and loss of sections of the adductor mandibulae most commonly adopted under the alphanumeric system additionally proved ontogenetically incongruent and less parsimonious than a model of subdivision and coalescence of facial muscle sections. Results of the analysis demonstrate the impossibility of adapting the alphanumeric terminology so as to reflect homologous entities across the spectrum of teleosts. A new nomenclatural scheme is proposed in order to achieve congruence between homology and nomenclature of the adductor mandibulae components across the entire Teleostei. PMID

  15. Short Communication Microsatellite loci in the tetraploid spined loach, Cobitis biwae, and cross-species amplification in four related species.

    PubMed

    Jablonska, O; Marín, A; Kowalewska, K; Fujimoto, T; Arai, K

    2016-09-23

    Fifteen microsatellite loci were identified in the tetraploid spined loach, Cobitis biwae (Teleostei: Cobitidae). Among these, 14 were polymorphic (5-31 alleles) and showed moderate to high cross-species amplification transferability in four related species, Cobitis matsubarai, Cobitis taenia, Misgurnus anguillicaudatus, and Misgurnus fossilis. The loci, described herein, will be useful for population genetics, phylogeny, parentage analysis, and detection of hybridization among Cobitis species.

  16. Sturgeon hatching enzyme and the mechanism of egg envelope digestion: Insight into changes in the mechanism of egg envelope digestion during the evolution of ray-finned fish.

    PubMed

    Nagasawa, Tatsuki; Kawaguchi, Mari; Sano, Kaori; Yasumasu, Shigeki

    2015-12-01

    We investigated the evolution of the hatching enzyme gene using bester sturgeon (hybrid of Acipencer ruthenus and Huso huso), a basal member of ray-finned fishes. We purified the bester hatching enzyme from hatching liquid, yielding a single band on SDS-PAGE, then isolated its cDNA from embryos by PCR. The sturgeon hatching enzyme consists of an astacin family protease domain and a CUB domain. The CUB domains are present in frog and bird hatching enzymes, but not in teleostei, suggesting that the domain structure of sturgeon hatching enzyme is the tetrapod type. The purified hatching enzyme swelled the egg envelope, and selectively cleaved one of five egg envelope proteins, ZPAX. Xenopus hatching enzyme preferentially digests ZPAX, thus, the egg envelope digestion process is conserved between amphibians and basal ray-finned fish. Teleostei hatching enzymes cleave the repeat sequences at the N-terminal region of ZPB and ZPC, suggesting that the targets of the teleostei hatching enzymes differ from those of amphibians and sturgeons. Such repeat sequences were not found in the N-terminal region of ZPB and ZPC of amphibians and sturgeons. Our results suggest that the change in substrates of the hatching enzymes was accompanied by the mutation of the amino acid sequence of N-terminal regions of ZPB and ZPC. We conclude that the changes in the mechanism of egg envelope digestion, including the change in the domain structure of the hatching enzymes and the switch in substrate, occurred during the evolution of teleostei, likely triggered by the teleost-specific third whole genome duplication. J. Exp. Zool. (Mol. Dev. Evol.) 324B: 720-732, 2015. © 2015 Wiley Periodicals, Inc.

  17. Recruitment patterns of young-of-the-year mugilid fishes in a West African estuary impacted by climate change

    NASA Astrophysics Data System (ADS)

    Trape, Sébastien; Durand, Jean-Dominique; Guilhaumon, François; Vigliola, Laurent; Panfili, Jacques

    2009-11-01

    With the persistence of the sub-Saharan drought since the 1970s, the Sine Saloum estuary (Senegal) - the second largest coastal Biosphere Reserve of West-Africa - has become an "inverse estuary" and hypersaline (salinity > 60) in its upstream part. A one-year survey was conducted from April 2007 to March 2008 at eight sites distributed along the salinity gradient, to investigate the recruitment patterns of young-of-the-year mugilids in such an impacted ecosystem. Fishes were sampled monthly with a conical net and a beach seine in salinities ranging from 31 to 104. Samples were identified to the species level. For the smallest individuals (<20 mm SL) a PCR-RFLP technique, developed on the mitochondrial 16S ribosomal RNA region, was used for identification. A total of 8438 juveniles belonging to six of the eight species of mugilids known for the tropical Eastern Atlantic were collected: Mugil bananensis, Mugil cephalus, Mugil curema, Liza dumerili, Liza falcipinnis and Liza grandisquamis. One species, L. dumerili, represented 89% of the total catch. Length-frequency distributions revealed that M. cephalus and L. dumerili preferentially recruited during the dry season whereas the recruitment of M. curema, M. bananensis and L. falcipinnis generally occurred during the wet season. Minimal size at recruitment ranged from 9 to 19 mm SL depending on the species, the smallest size being that of L. dumerili. Despite the general salinity increase in the estuary, most parts of the Sine Saloum were suitable for the juveniles. Only the hypersaline area in the uppermost part of the estuary presented very low fish abundance for all species. According to the species, small recruits (12-20 mm SL) were collected at salinities up to 47-78, suggesting that osmoregulatory capacities had been gained early during ontogenesis, possibly resulting from an adaptation of these populations to changing environmental conditions.

  18. New records of Caligidae (Copepoda, Siphonostomatoida) from the Philippines.

    PubMed

    Maran, Balu Alagar Venmathi; Cruz-Lacierda, Erlinda R; Ohtsuka, Susumu; Nagasawa, Kazuya

    2016-10-11

    Parasitic copepods, especially sea lice (Caligidae) are causing economic problems in both aquaculture and to wild fishes around the world, but their study in at least some of the southeastern Asian countries, is still scanty. Here we provide new information on the distribution of 11 known species of parasitic copepods collected from 11 marine fish hosts from Iloilo, central part of the Philippines. Two species of the genus Anuretes Heller, 1865 and nine species of the genus Caligus Müller, 1785 were found to infest these hosts, i.e. Anuretes branchialis Rangnekar, 1953 from Platax orbicularis (Forsskål, 1775); A. plectorhynchi Yamaguti, 1936 from P. orbicularis and Plectorhinchus pictus (Tortonese, 1936); Caligus absens Ho, Lin et Chen, 2000 from Priacanthus macracanthus Cuvier in Cuvier & Valenciennes, 1829; C. asymmetricus Kabata, 1965 and C. coryphaenae (Steenstrup & Lütken, 1861) from Auxis thazard (Lacepède, 1800); C. bonito Wilson, 1905 from Coryphaena hippurus Linnaeus, 1758; C. cordyla Pillai, 1963 from Megalaspis cordyla (Linnaeus, 1758); C. cornutus Heegaard, 1962 from Sphyraena jello Cuvier in Cuvier & Valenciennes, 1829; C. epinepheli Yamaguti, 1936 from Scomberoides commersonnianus Lacepède, 1801; C. kanagurta Pillai, 1961 from Decapterus kurroides Bleeker, 1855, D. macarellus (Cuvier in Cuvier & Valenciennes, 1833) and C. hippurus; and C. rotundigenitalis Yü, 1933 from Scatophagus argus (Linnaeus, 1766). Attachment sites included the gill filaments and the body surface. Prevalence and mean intensity of caligids are provided in addition to an update on the checklist of caligids of the Philippines. Although reports on caligids in the Philippines are few, the published records indicate that sea lice are widely distributed throughout the archipelago.

  19. Four new records of fish species (Cypriniformes: Nemacheilidae, Balitoridae; Characiformes: Prochilodontidae) and corrections of two misidentified fish species (Tetraodontiformes: Tetraodontidae; Beloniformes: Belonidae) in Yunnan, China

    PubMed Central

    Endruweit, Marco

    2014-01-01

    In this study, six fish species of five families are reported for the first time from Yunnan Province, China. The nemacheilid Schistura amplizona Kottelat, 2000 is reported from the Luosuojiang River and Nanlahe River subbasins, Mekong basin; the prochilodontid Prochilodus lineatus (Valenciennes, 1837), the balitorid Vanmanenia serrilineata Kottelat, 2000, and the tetraodontid Monotrete turgidus Kottelat, 2000, from Nanlahe River subbasin, Mekong basin; the balitorid Beaufortia daon (Mai, 1978), and the belonid Xenentodon canciloides (Bleeker, 1854), both, from Black River subbasin, Red River basin. The freshwater puffer M. turgidus and the needlefish X. canciloides have been previously misidentified as Tetraodon leiurus (Bleeker, 1950) and Tylosurus strongylurus (van Hasselt, 1823), respectively. PMID:24470454

  20. Udonella australis n. sp. (Monogenea), an epibiont on sea-lice from native fish off southern Chile.

    PubMed

    Carvajal, Juan; Sepúlveda, Fabiola

    2002-05-01

    Udonella australis n. sp., an epibiont monogenean living on caligid copepods that infest a native fish, Eleginops maclovinus (Valenciennes), off Chile, South America is described. The species can be separated from other species by its difference in size, especially body size, and the distribution of cephalic glands, vitelline follicles and genital organs. Egg-size is intermediate in comparison with that of other species. The posterior attachment mechanism consists of few muscle fibres and clumped cement-producing glands. All previous descriptions of Udonella caligorum Johnston, 1835 from off Chile correspond to this new species.

  1. Four new records of fish species (Cypriniformes: Nemacheilidae, Balitoridae; Characiformes: Prochilodontidae) and corrections of two misidentified fish species (Tetraodontiformes: Tetraodontidae; Beloniformes: Belonidae) in Yunnan, China.

    PubMed

    Endruweit, Marco

    2014-01-01

    In this study, six fish species of five families are reported for the first time from Yunnan Province, China. The nemacheilid Schistura amplizona Kottelat, 2000 is reported from the Luosuojiang River and Nanlahe River subbasins, Mekong basin; the prochilodontid Prochilodus lineatus (Valenciennes, 1837), the balitorid Vanmanenia serrilineata Kottelat, 2000, and the tetraodontid Monotrete turgidus Kottelat, 2000, from Nanlahe River subbasin, Mekong basin; the balitorid Beaufortia daon (Mai, 1978), and the belonid Xenentodon canciloides (Bleeker, 1854), both, from Black River subbasin, Red River basin. The freshwater puffer M. turgidus and the needlefish X. canciloides have been previously misidentified as Tetraodon leiurus (Bleeker, 1950) and Tylosurus strongylurus (van Hasselt, 1823), respectively.

  2. Complete mitochondrial genome of the Easten hulafish, Trachinops taeniatus (Perciformes: Plesiopidae).

    PubMed

    Xia, Rong; Fu, Cuizhang

    2015-01-01

    The first complete mitochondrial genome (mitogenome) of Plesiopidae (Teleostei: Perciformes) was determined using the Eastern hulafish Trachinops taeniatus as a representative species of the family. The mitogenome was 16,821 bp in length, including 13 typical vertebrate protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 1 control region. The gene arrangement was similar to other fishes except for the reversal position of tRNA(Ala) and tRNA(Asn). The overall base composition was 27.4% for A, 27.5% for C, 27.4% for T and 17.7% for G. This mitogenome should contribute to resolving phylogenetic position of Plesiopidae.

  3. Gyrodactylus aff. mugili Zhukov, 1970 (Monogenoidea: Gyrodactylidae) from the gills of mullets (Mugiliformes: Mugilidae) collected from the inland waters of southern Iraq, with an evalutation of previous records of Gyrodactylus spp. on mullets in Iraq.

    PubMed

    Kritsky, Delane C; Ali, Atheer H; Khamees, Najim R

    2013-11-01

    Gyrodactylus aff. mugili Zhukov, 1970 (Monogenoidea: Gyrodactylidae) is recorded and described from the gill lamellae of 11 of 35 greenback mullet, Chelon subviridis (Valenciennes) (minimum prevalence 31%), from the brackish waters of the Shatt Al-Arab Estuary in southern Iraq. The gyrodactylid was also found on the gill lamellae of one of eight Speigler's mullet, Valamugil speigleri (Bleeker), from the brackish waters of the Shatt Al-Basrah Canal (minimum prevalence 13%). Fifteen Klunzinger's mullet, Liza klunzingeri (Day), and 13 keeled mullet, Liza carinata (Valenciennes), collected and examined from southern Iraqi waters, were apparently uninfected. The gyrodactylids from the greenback mullet and Speigler's mullet were considered to have affinity to G. mugili Zhukov, 1970, and along with G. mugili may represent members of a species complex occurring on mullets in the Indo-Pacific Region. A single damaged gyrodactylid from the external surfaces of the abu mullet, Liza abu (Heckel), was insufficient for species identification. Previously identified species of Gyrodactylus recorded on L. abu in Iraq by various authors were considered possible misidentifications or accidental infections.

  4. Piscine aquaporins: an overview of recent advances.

    PubMed

    Cerdà, Joan; Finn, Roderick Nigel

    2010-12-01

    Aquaporins are a superfamily of integral membrane proteins that facilitate the rapid and yet highly selective flux of water and other small solutes across biological membranes. Since their discovery, they have been documented throughout the living biota, with the majority of research focusing on mammals and plants. Here, we review available data for piscine aquaporins, including Agnatha (jawless fish), Chondrichthyes (chimaeras, sharks, and rays), Dipnoi (lungfishes), and Teleostei (ray-finned bony fishes). Recent evidence suggests that the aquaporin superfamily has specifically expanded in the chordate lineage consequent to serial rounds of whole genome duplication, with teleost genomes harboring the largest number of paralogs. The selective retention and dichotomous clustering of most duplicated paralogs in Teleostei, with differential tissue expression profiles, implies that novel or specialized physiological functions may have evolved in this clade. The recently proposed new nomenclature of the piscine aquaporin superfamily is discussed in relation to the phylogenetic signal and genomic synteny, with the teleost aquaporin-8 paralogs used as a case study to illustrate disparities between the underlying codons, molecular phylogeny, and physical locus. Structural data indicate that piscine aquaporins display similar channel restriction residues found in the tetrapod counterparts, and hence their functional properties seem to be conserved. However, emerging evidence suggests that regulation of aquaporin function in teleosts may have diverged in some cases. Cell localization and experimental studies imply that the physiological roles of piscine aquaporins extend at least to osmoregulation, reproduction, and early development, although in most cases their specific functions remain to be elucidated.

  5. Bichir microRNA repertoire suggests a ray-finned fish affinity of Polypteriforme.

    PubMed

    Yang, Liandong; Zhang, Zhaolei; He, Shunping

    2015-07-25

    The phylogenetic position of Polypteriforme (bichirs) remains elusive, despite extensive research both on morphological and molecular datasets. Unfortunately morphological cladistic analyses and molecular phylogenetic analyses had reached conflicting conclusions, as Polypteriformes were either grouped with lobe-finned fishes (Sarcopterygii) or ray-finned fishes (Actinopterygii), or even classified as their own group, the Brachiopterygii. In this study, we applied a third independent source of datasets, the presence versus absence of microRNAs, to re-investigate the phylogenetic relationship of bichirs. Through deep sequencing of small RNA library, we showed that bichirs should be grouped into ray-finned fishes rather than lobe-finned fishes. Phylogenetic analysis confirmed that bichirs were placed as the most basal member of the ray-finned fishes. Bichirs shared five unique microRNA families with teleostei, which were not found in any other species investigated to date. Bichirs have also retained three of five microRNAs that were previously deemed to be lost exclusively in teleostei. Furthermore, we report more than one hundred novel microRNAs that are unique to bichir. The identification of microRNAs in bichir provides overwhelming evidence for their affinity of ray-finned fishes. The sarcopterygian-like characteristics such as lobed fins, paired ventral lungs, and external gills in juveniles should not be considered as derived traits shared with those of sarcopterygians.

  6. Possible identification of CENP-C in fish and the presence of the CENP-C motif in M18BP1 of vertebrates.

    PubMed Central

    Kral, Leos

    2016-01-01

    The centromeric protein CENP-C is a base component of the kinetochore. This protein, along with CENP-A has been shown to adaptively evolve in a number of animal and plant species. In order to determine if CENP-C also evolves in fish species, I attempted to retrieve fish CENP-C sequences from GenBank. No Teleostei CENP-C sequences were found either by name or by BLASTP searches with the vertebrate CENP-C motif sequence. A number of putative Teleostei protein sequences were identified in GenBank that have homology to the C-terminal cupin domain of vertebrate CENP-C. These proteins only have partial homology to the CENP-C motif, but evidence is presented that makes it likely that these fish proteins are orthologs of CENP-C. Interestingly, it was also discovered that the CENP-C motif sequence is also mostly present in M18BP1 proteins of fish and some other vertebrates but not in mammals. This finding may have implications for CENP-C and M18BP1 assembly in centromeric regions of different vertebrate taxa. PMID:27127616

  7. [Species and size composition of fishes in Barra de Navidad lagoon, Mexican central Pacific].

    PubMed

    González-Sansón, Gaspar; Aguilar-Betancourt, Consuelo; Kosonoy-Aceves, Daniel; Lucano-Ramírez, Gabriela; Ruiz-Ramírez, Salvador; Flores-Ortega, Juan Ramón; Hinojosa-Larios, Angel; de Asís Silva-Bátiz, Francisco

    2014-03-01

    Coastal lagoons are considered important nursery areas for many coastal fishes. Barra de Navidad coastal lagoon (3.76km2) is important for local economy as it supports tourism development and artisanal fisheries. However, the role of this lagoon in the dynamics of coastal fish populations is scarcely known. Thus, the objectives of this research were: to characterize the water of the lagoon and related weather conditions, to develop a systematic list of the ichthyofauna, and to estimate the proportion of juveniles in the total number of individuals captured of most abundant species. Water and fish samples were collected between March 2011 and February 2012. Physical and chemical variables were measured in rainy and dry seasons. Several fishing gears were used including a cast net, beach purse seine and gillnets of four different mesh sizes. Our results showed that the lagoon is most of the time euhaline (salinity 30-40ups), although it can be mixopolyhaline (salinity 18-30ups) during short periods. Chlorophyll and nutrients concentrations suggested eutrophication in the lagoon. Mean water temperature changed seasonally from 24.9 degrees C (April, high tide) to 31.4 degrees C (October, low tide). Considering ichthyofauna species, a total of 36 448 individuals of 92 species were collected, 31 of them adding up to 95% of the total of individuals caught. Dominant species were Anchoa spp. (44.6%), Diapterus peruvianus (10.5%), Eucinostomus currani (8.1%), Cetengraulis mysticetus (7.8%), Mugil curema (5.2%) and Opisthonema libertate (4.5%). The lagoon is an important juvenile habitat for 22 of the 31 most abundant species. These included several species of commercial importance such as snappers (Lutjanus argentiventris, L. colorado and L. novemfasciatus), snook (Centropomus nigrescens) and white mullet (Mugil curema). Other four species seem to use the lagoon mainly as adults. This paper is the first contribution on the composition of estuarine ichthyofauna in Jalisco

  8. A review of the genus Sclerocollum Schmidt & Paperna, 1978 (Acanthocephala: Cavisomidae) from rabbitfishes (Siganidae) in the Indian and Pacific Oceans.

    PubMed

    Pichelin, Sylvie; Smales, Lesley R; Cribb, Thomas Herbert

    2016-02-01

    Seven of the eleven species of Siganus Richardson (Siganidae) collected off the coasts of Australia, New Caledonia, French Polynesia and Palau were infected with species of Sclerocollum Schmidt & Paperna, 1978 (Acanthocephala: Cavisomidae). A Principal Component Analysis (PCA) and a Discriminant Analysis were performed on a morphometric dataset of specimens of Sclerocollum including borrowed type-specimens of Sc. rubrimaris Schmidt & Paperna, 1978 from the Indian Ocean and of Sc. robustum Edmonds, 1964, the only acanthocephalan species known previously from an Australian siganid. These analyses showed that the lengths of proboscis hooks were useful variables for separating specimens into groups and supported the presence of two known species (Sc. robustum and Sc. rubrimaris) and one new species (Sc. australis n. sp.) in Australian waters. We found Sc. robustum in Siganus lineatus (Valenciennes) from off Queensland and Sc. rubrimaris in S. fuscescens (Houttuyn) from off Western Australia and Queensland, S. punctatissimus Fowler & Bean from off Queensland and S. argenteus (Quoy & Gaimard), S. corallinus (Valenciennes), S. canaliculatus (Park) and S. doliatus Guérin-Méneville from off New Caledonia (all new host and locality records) which we compared with museum specimens of Sc. rubrimaris from S. rivulatus Forsskål & Niebuhr and S. argenteus [as S. rostratus (Valenciennes)] from the Red Sea. The third species, Sclerocollum australis n. sp., was found only in S. corallinus and S. doliatus from off Queensland. Sclerocollum australis n. sp. can be distinguished from its congeners by a unique combination of characters of the proboscis armature, including lengths of hooks 1-7. Specimens of Sclerocollum were also found in Zebrasoma velifer (Bloch) (Acanthuridae) from off Queensland, and Coradion altivelis McCulloch (Chaetodontidae) and Heniochus acuminatus (Linnaeus) (Chaetodontidae) from off New Caledonia. No acanthocephalans were found in siganids collected from

  9. Analysis of the Body Distribution of Absorbed Dose in the Organs of Three Species of Fish from Sepetiba Bay

    NASA Astrophysics Data System (ADS)

    Pereira, Wagner de S.; Kelecom, Alphonse; dos Santos Gouvea, Rita de Cássia; Py Júnior, Delcy de Azevedo

    2008-08-01

    The body distribution of Polonium-210 in three fishes from the Sepetiba Bay (Macrodon ancylodon, Micropogonias furnieri and Mugil curema) has been studied under the approach of the Department of Energy of the United States of America (DOE) that set the limit of absorbed dose rate in biota equal to 3.5×103 μGy/y, and that also established the relation between dose rate (D) and radionuclide concentration (c) on a fish muscle fresh weight basis, as follows: D = 5.05 E×N×C, assuming that the radionuclide distribution is homogenous among organs. Two hypotheses were tested here, using statistical tools: 1) is the body distribution of absorbed dose homogenous among organs? and 2) is the body distribution of absorbed dose identical among studied fishes? It was concluded, as expected, that the distribution among organs is heterogeneous; but, unexpectedly, that the three fishes display identical body distribution pattern, although they belong to different trophic levels. Hence, concerning absorbed dose calculation, the statement that data distribution is homogenous must be understood merely as an approximation, at least in the case of Polonium-210.

  10. Effects of hypoxia on movements and behavior of selected estuarine organisms from the southeastern United States.

    PubMed

    Wannamaker; Rice

    2000-06-28

    Hypoxia, or low dissolved oxygen, remains a common occurrence in estuarine waters as human activity in coastal areas expands. Fish kills, probably the most recognized indicator of these and other water quality problems, have significantly increased in recent years in many Southeastern United States estuaries. While entire aquatic communities are impacted by changes in available oxygen, estuarine organisms serve as appropriate indicators of these changes as they exhibit complex physiological and behavioral responses to hypoxia. The consequences of hypoxia for these species depend on their ability to detect and avoid areas of low dissolved oxygen. We conducted a series of two-way, replicated choice experiments with juvenile spot (Leiostomus xanthurus), pinfish (Lagodon rhomboides), croaker (Micropogonias undulatus), menhaden (Brevoortia tyrannus), white mullet (Mugil curema), mummichog (Fundulus heteroclitus), and brown shrimp (Penaeus aztecus) to determine their ability to detect and avoid specific levels of hypoxia. Additional data on organisms' movement patterns, aquatic surface respiration, and ventilation rates were collected. All species tested could detect and avoid 1 mgl(-1) dissolved oxygen. The hypoxia avoidance response differed among species, as some species exhibited an avoidance threshold while others exhibited a graded avoidance response. These data supply baseline information necessary to assess how some mobile estuarine organisms respond behaviorally to oxygen concentrations, and to understand how hypoxia more broadly impacts fish populations and estuarine community health.

  11. Fishes as indicators of untreated sewage contamination in a Mexican coastal lagoon.

    PubMed

    Aguilar-Betancourt, Consuelo M; González-Sansón, Gaspar; Kidd, Karen A; Munkittrick, Kelly R; Curry, R Allen; Kosonoy-Aceves, Daniel; Lucano-Ramírez, Gabriela; Ruiz-Ramírez, Salvador; Flores-Ortega, Juan R

    2016-12-15

    Lagoons are important nursery habitats for fishes but are often sites of intense human activity including wastewater discharges. The goal of this research was to compare stable nitrogen (δ(15)N) and carbon (δ(13)C) isotopes, total mercury (THg) and other metal levels in four selected fish species among sites with different levels of untreated sewage discharge inside Barra de Navidad coastal lagoon in the Mexican Pacific. Three species from sites heavily impacted by sewage showed higher δ(15)N and δ(13)C compared to those from non-impacted sites. In addition, the highest concentrations of THg were present in fish of two species (Sciades guatemalensis and Diapterus brevirostris) collected at the two most impacted sites, and exceeded the 0.2μg/g ww threshold believed to be protective of adult and juvenile fish. No individuals of Achirus mazatlanus and Mugil curema exceeded this threshold, and liver somatic index and condition did not distinguish high from low impacted sites for all species. In general, the metal levels differed among species but not sites, and were lower than what has been measured in fishes elsewhere. The study also provides the first information on several fish species for coastal areas of Mexico, suggests that THg and isotopes can distinguish sewage-impacted sites, and can serve as a baseline for future studies.

  12. [Spatial and temporal variation of the fish community inhabiting the Laguna Grande de Obispo, Gulf of Cariaco, Sucre State, Venezuela].

    PubMed

    de Grado, A A; Bashirullah, A; Prieto, A

    2000-01-01

    The monthly species composition and the spatial and temporal variation of fish community of Laguna Grande de Obispo, Gulf of Canaco, Sucre State, Venezuela were analyzed. The samples were collected using two beach seines of different size from December 1995 to November 1996. A cluster analysis for stations inside the lagoon and time of capture showed 4 major groups, defined principally with ecological parameters of each area. Fishing with large seine in and outside the lagoon showed two large groups which were divided into 10 subgroups in function of station and time, while an inverse analysis of the same sample differentiated into 8 groups of species. based on distribution, dominance, and occurrence. Xenomeianiris brasiliensis, Mugil curema and Eucinostomus argenteus were the most abundant species in both time and space. An analysis of conglomerate on the whole fish community of the sampling period indicated the existence of two groups: i) the first half of the year including December 1995 and October 1996 and ii) the second half of the year. The distribution of fishes in relation to ecological factors is discussed.

  13. Analysis of the Body Distribution of Absorbed Dose in the Organs of Three Species of Fish from Sepetiba Bay

    SciTech Connect

    Pereira, Wagner de S; Kelecom, Alphonse; Santos Gouvea, Rita de Cassia dos; Azevedo Py Junior, Delcy de

    2008-08-07

    The body distribution of Polonium-210 in three fishes from the Sepetiba Bay (Macrodon ancylodon, Micropogonias furnieri and Mugil curema) has been studied under the approach of the Department of Energy of the United States of America (DOE) that set the limit of absorbed dose rate in biota equal to 3.5x10{sup 3} {mu}Gy/y, and that also established the relation between dose rate (D) and radionuclide concentration (c) on a fish muscle fresh weight basis, as follows: D = 5.05 ExNxC, assuming that the radionuclide distribution is homogenous among organs. Two hypotheses were tested here, using statistical tools: 1) is the body distribution of absorbed dose homogenous among organs? and 2) is the body distribution of absorbed dose identical among studied fishes? It was concluded, as expected, that the distribution among organs is heterogeneous; but, unexpectedly, that the three fishes display identical body distribution pattern, although they belong to different trophic levels. Hence, concerning absorbed dose calculation, the statement that data distribution is homogenous must be understood merely as an approximation, at least in the case of Polonium-210.

  14. Gamma ionization of Phagicola longa (Trematoda:Heterophyidae) in Mugilidae (pisces) in São Paulo, Brazil

    NASA Astrophysics Data System (ADS)

    Antunes, S. A.; Wiendl, F. M.; Almeida Dias, E. R.; Arthur, V.; Daniotti, C.

    1993-07-01

    The mullet (Mugilidae) is a fish caught in large quantities in brackish and marine waters of the southern Brazilian coast, which in consequence of its raw consumption as "sashimi", a typical Japanese dish, has led to ten cases of human infection by Phagicola longa in São Paulo, Brazil. The mullet acts as a second intermediate host for the parasite, as in human heterophysiasis in the Near and Far East. In order to control these infections under commercial storage conditions and in raw consumption, the radiolysis of P. longa was studied in three mullet species-the silver mullet ( Mugil curema), the grey mullet ( M. platanus) and the "paratipema" ( Mugil sp.) - subjected to ionization ranging from 1.0 to 10.0 kGy (2.21 kGy/h). It was observed that 1.0 and 2.0 kGy caused a motility decrease in silver mullet parasites from 100% to 15% and 17%, and that doses of 4.0 and 10.0 kGy caused metacercaria inviability. The parasite motility decreased in the grey mullet treated with doses of 2.0, 2.5, 3.0 and 3.5 kGy, from 56% to 31%, 9%, 18% and 5%, respectively, 4.0 kGy tending to be the control dose for P. longa. This dose also controls other metacercaria found in the "parati-pema", without changing the odor, color or appearance of the treated mullet.

  15. Validity of a blue stripe snapper, Lutjanus octolineatus (Cuvier 1828) and a related species, L. bengalensis (Bloch 1790) with a new species (Pisces; Lutjanidae) from the Arabian Sea.

    PubMed

    Iwatsuki, Yukio; Al-Mamry, Juma M; Heemstra, Phillip C

    2016-04-07

    Lutjanus octolineatus (Cuvier 1828), previously considered a junior synonym of Lutjanus bengalensis (Bloch 1790), is shown to be a valid species and lectotypes are designated. Both species are redescribed. The two species have overlapping distributions in the Indian Ocean, but are clearly separable by different dorsal-fin spine counts, blue-striped pattern on the body and the presence or absence of a subocular extension of cheek scales. Lutjanus octovittata (Valenciennes 1830), formerly assigned to synonymy of L. bengalensis, is considered a junior synonym of L. octolineatus based on examination of the holotype. Lutjanus sapphirolineatus n. sp., a species formerly misidentified as L. bengalensis, is described based on 10 specimens from Oman and Somalia. The new species differs from the three species above by a combination of different characters. Analysis of the mitochondrial cytochrome c oxidase subunit 1 (CO1, 603 bp) genetic marker, also strongly supports the validity of each species of the blue-striped snapper complex as distinct.

  16. Redescription and morphometric analysis of Paramazocraes thrissocles Tripathi, 1959 and P. setipinna Zhang & Ding in Zhang, Yang & Liu, 2001 (Monogenea: Mazocraeidae) infecting clupeoid fishes off Visakhapatnam coast, Bay of Bengal.

    PubMed

    Sailaja, Bade; Shameem, Ummey; Madhavi, Rokkam

    2016-02-01

    Two species of the mazocraeid monogenean genus Paramazocraes Tripathi, 1959 are redescribed based on specimens collected from the gills of clupeoid fishes off the Visakhapatnam coast, Bay Bengal: Paramazocraes thrissocles Tripathi, 1959 from Thryssa mystax (Bloch & Schneider), T. setirostris (Broussonet), T. malabarica (Bloch) and Paramazocraes setipinna Zhang & Ding in Zhang, Yang & Liu, 2001 from Setipinna taty (Valenciennes). The two species were subjected to morphological and morphometric analyses. The study revealed that P. thrissocles and P. setipinna differ mainly in the number, size and arrangement of the testes. A review of the genus Paramazocraes is provided and the validity of some of the Indian species of the genus is discussed. Sequences of the 28S rRNA gene for the two species are deposited in the GenBank.

  17. Sunagocia omanensis, a new flathead fish (Scorpaeniformes, Platycephalidae) from the Western Indian Ocean, with comments on the distribution of Sunagocia carbuncular.

    PubMed

    Knapp, Leslie W; Randall, John E

    2013-01-01

    A new species of Platycephalidae having a weak development of sensory tubules on the cheek is placed in the genus Sunagocia Imamura. The description is based on two specimens taken at the Kuria Muria Ids., Oman. The new species may be distinguished from its congeners by having three preocular spines, ethmoid spines forming a rosette on mid-line with 5-6 tips coming from a common base, and a body coloration of tan with dark saddles reaching to lower sides. It is also characterized by having numerous small serrations along the supraorbital and suborbital ridges and sixgill rakers. A section concerning the status and range of Sunagocia carbuncula Valenciennes in the western Indian Ocean is also included. A key separating the species of Sunagocia appears below.

  18. A new Huffmanela species, H. schouteni sp. n. (Nematoda: Trichosomoididae) from flying fishes in Curaçao.

    PubMed

    Moravec, F; Campbell, B G

    1991-01-01

    A new nematode species, Huffmanela schouteni sp. n., has been established on the basis of its egg morphology and biological characters (adult nematodes are unknown). The dark-shelled eggs of this histozoic parasite occur in masses in the abdominal cavity, serose covers of internal organs and in the liver of the flying fishes Hirundichthys affinis Günther (type host) and Cypselurus cyanopterus Cuvier et Valenciennes in Curaçao. The eggs of H. schouteni sp. n.