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Sample records for galaxias maculatus teleostei

  1. [New metacercariae of the genus Tylodelphys (Trematoda, Diplostomatidae) in lacustrine populations of Galaxias maculatus (Teleostei, Galaxiidae)].

    PubMed

    Quaggiotto, E A; Valverde, F

    1992-01-01

    Metacercariae of three new species of Tylodelphys (Trematoda, Diplostomatidae) were found in the brain of Galaxias maculatus (Teleostei, Galaxiidae), at the Meliquina Lake, Neuquen Province, Argentina. These metacercariae are morphologically described as Tylodelphys argentinus n. sp., Tylodelphys barilochensis n. sp. and Tylodelphys crubensis n. sp. This is the first time that a stage of genus Tylodelphys is mentioned parasitizing Galaxias maculatus. Metacercariae of T. barilochen sis n. sp. were also found in G. maculatus brain at the Perito Moreno Lake, Rio Negro Province, Argentina. PMID:1306987

  2. [Contribution to the morphological description of Tylodelphys barilochensis and Tylodelphys crubensis (Trematoda, Diplostomidae) encephalon parasites of Galaxias maculatus (Teleostei, Galaxiidae)].

    PubMed

    Flores, V

    1997-01-01

    Taxonomic characteristics, for species identification, of metacercarie of T. barilochensis and T. crubensis found in the encephalon of the fish Galaxias maculatus, not included in the original descriptions, particularly those concerning to the excretory system, are described. PMID:9640687

  3. Aspects of the biology of Galaxias maculatus.

    PubMed

    Laurenson, L J B; French, R P; Jones, P; Ierodiaconou, D; Gray, S; Versace, V L; Rattray, A; Brown, S; Monk, J

    2012-08-01

    The biology of three landlocked and a riverine population of Galaxias maculatus were examined in western Victoria, Australia. All systems supported reproducing populations of these fish, including Lake Corangamite which had salinities that on occasion reached 82. Spawning sites in Lake Corangamite were located in adjacent tributaries and not in the main lake as was the case for other populations. The smallest fish were found in the fresh water Lake Purrumbete and the largest in the hypersaline Lake Corangamite. The size at which 50% of the population attained sexual maturity varied across sites, with fish maturing at a smaller size in Lake Purrumbete, followed by the Merri River, Lake Bullen Merri and Lake Corangamite. Condition was higher in the freshwater Lake Purrumbete and there was no relationship between condition and temperature, conductivity, turbidity and pH; but there was a positive relationship between condition and dissolved oxygen. Length frequency analysis suggested that the majority of fishes live for a year. PMID:22880739

  4. A novel oxyconforming response in the freshwater fish Galaxias maculatus.

    PubMed

    Urbina, Mauricio A; Glover, Chris N; Forster, Malcolm E

    2012-03-01

    How fish oxygen consumption is modulated by external PO(2) has long been a matter of interest, yet is an experimentally complicated question to answer. In this study closed and semi-closed respirometry were used to evaluate the oxygen consumption rate of the scaleless galaxiid fish, inanga (Galaxias maculatus) as a function of decreasing external PO(2). Both respirometry techniques showed that as environmental oxygen levels declined, oxygen consumption rates also decreased. At no point did inanga regulate oxygen consumption. This is strong evidence that inanga is an oxyconformer. Partitioned respirometry experiments showed that skin plays an important role in oxygen uptake in this fish species, and cutaneous oxygen uptake may have an important role in shaping the oxygen consumption response to hypoxia. PMID:22138470

  5. Mechanisms of zinc toxicity in the galaxiid fish, Galaxias maculatus.

    PubMed

    McRae, Nicole K; Gaw, Sally; Glover, Chris N

    2016-01-01

    Zinc (Zn) is an essential metal, which is ubiquitous in aquatic environments occurring both naturally, and through anthropogenic inputs. This study investigated impacts of sub-lethal Zn exposure in the galaxiid fish Galaxias maculatus. Known as inanga, this amphidromous fish is widespread throughout the Southern hemisphere, but to date almost nothing is known regarding its sensitivity to elevated environmental metals. Fish were exposed to environmentally-relevant concentrations of Zn (control, 8, 270 and 1000μgL(-1)) over 96h. End-points measured included those relating to ionoregulatory disturbance (whole body calcium and sodium influx), oxygen consumption (respirometry), oxidative stress (catalase activity and lipid peroxidation) and whole body accumulation of Zn. Zn exposure caused increases in catalase activity and lipid peroxidation, but only at the highest exposure level tested. Zn also significantly inhibited calcium influx, but stimulated sodium influx, at 1000μgL(-1). The sub-lethal changes induced by Zn exposure in inanga appear to be conserved relative to other, better-studied species. These data are the first to explore the sensitivity of juvenile galaxiid fish to Zn, information that will be critical to ensuring adequate environmental protection of this important species. PMID:26510681

  6. Post-settlement migratory behaviour and growth-related costs in two diadromous fish species, Galaxias maculatus and Galaxias brevipinnis.

    PubMed

    Jung, C A; Barbee, N C; Swearer, S E

    2009-08-01

    The physiological challenges incurred during the transition from sea to fresh water and the constraints they place on the rate at which the common galaxiid Galaxias maculatus and the climbing galaxiid Galaxias brevipinnis can migrate from marine to freshwater habitats were examined. The duration of the marine to freshwater transition, the relationship between post-settlement age (PSA) and standard length (L(S)) as a proxy for energetic costs incurred during settlement and the potential effects of estuary geomorphology on migratory behaviour was investigated. Rate of upstream migration after settlement was not uniform. Upstream migration rate was slowest directly after settlement and increased with increasing PSA and distance from the river mouth, indicating a delay in upstream migration by newly recruited galaxiids. L(s) did not increase with age, at least within the first 21 days post settlement. These patterns were consistent for both species, in spite of differences in their life histories, across the recruitment season, despite seasonal variation in recruit size, and among estuaries with different properties. The results suggest that the timing and speed of migratory behaviour primarily reflect physiological constraints. Given the duration of residency of these species in estuaries, this study indicates that estuaries are critical transitional habitats for diadromous fishes during their migration from marine to freshwater habitats. PMID:20738553

  7. Ten novel microsatellite loci characterized for a remarkably widespread fish: Galaxias maculatus (Galaxiidae).

    PubMed

    Carrea, Cecilia; Paterson, Ian G; Cussac, Victor E; Ruzzante, Daniel E

    2009-11-01

    Ten polymorphic microsatellite markers (five tetra-, one compound tetra-, one octa- and three dinucleotides) were isolated and characterized for Galaxias maculatus, a fish species widely distributed in the Southern Hemisphere. Markers were tested in 89 individual samples from a single location and the number of alleles ranged between 2 and 28. Observed and expected heterozygosities ranged from 0.103 to 0.910 and 0.098 to 0.935 respectively. No evidence was detected for either linkage disequilibrium (P-values > 0.05 for each locus pair) or deviations from HWE (P-values > 0.05 for every loci). PMID:21564945

  8. Myxidium biliare sp. n. (Myxozoa) from gall bladder of Galaxias maculatus (Osmeriformes: Galaxiidae) in Patagonia (Argentina).

    PubMed

    Viozzi, Gustavo P; Flores, Verónica R

    2003-09-01

    Myxidium biliare sp. n., a new myxosporean species parasitizing the gall bladder of Galaxias maculatus (Jenyns), in Patagonia, is described. Its coelozoic plasmodia were floating free in the bile. Spores are fusiform 13.7 +/- 0.9 microm long and 6.9 +/- 0.6 microm wide, with rounded ends in frontal view and slightly pointed ends in sutural view; shell with ridges and sinuous sutural line. Both maximum prevalence and maximum percentage of immature plasmodia occurred in summer. In winter the prevalence and the percentage of immature plasmodia fell to their lowest values. Prevalence was independent of host sex but increased with host length. Prevalence in 15 Patagonian Andean lakes (situated from 39 degrees 25'S to 41 degrees 30'S) ranged between 4.2% and 70%. PMID:14535344

  9. Infection of Myxobolus galaxii (Myxozoa) in Galaxias maculatus (Osmeriformes: Galaxiidae) from northwestern Patagonian Andean lakes (Argentina).

    PubMed

    Flores, Verónica; Viozzi, Gustavo

    2007-04-01

    The infection of Myxobolus galaxii Szidat, 1953, from the musculature and abdominal organs of northwestern Patagonian Galaxias maculatus is described. Plasmodia are histozoic and intercellular. Spores are pyriform in valvar view and biconvex in sutural view, with 4-9 edge notches in the sutural line, varying in shape within the same plasmodium. Myxobolus galaxii was detected in fish from 7 of 17 Andean Patagonian lakes, with prevalences ranging between 2 and 17%. A repeating pattern of summer increment in prevalence was observed, which could be explained by the ontogenetic migratory movements of the fish in Lake Gutiérrez. Also, accumulation of plasmodia through the life span of fish was detected. PMID:17539428

  10. Acanthocephalus tumescens (Acanthocephala, Echinorhynchidae) in Galaxias maculatus (Pisces, Galaxiidae) of Lake Gutiérrez, Patagonia, Argentina.

    PubMed

    Trejo, A; Semenas, L; Viozzi, G

    2000-02-01

    The seasonal distribution of Acanthocephalus tumescens (Acanthocephala : Echinorhynchidae) among Galaxias maculatus (Pisces : Galaxiidae) in Lake Gutiérrez was studied from March 1994 to June 1996. Acanthocephalus tumescens always occurs in the intestine, has an overdispersed frequency distribution, a similar proportion of sexes, and females are larger than males. Mean intensity and prevalence are low and increase with host length. The pattern of the infection shows seasonality, with recruitment in winter and a reproductive period during spring-summer. PMID:10701591

  11. Surviving historical Patagonian landscapes and climate: molecular insights from Galaxias maculatus

    PubMed Central

    2010-01-01

    Background The dynamic geological and climatic histories of temperate South America have played important roles in shaping the contemporary distributions and genetic diversity of endemic freshwater species. We use mitochondria and nuclear sequence variation to investigate the consequences of mountain barriers and Quaternary glacial cycles for patterns of genetic diversity in the diadromous fish Galaxias maculatus in Patagonia (~300 individuals from 36 locations). Results Contemporary populations of G. maculatus, east and west of the Andes in Patagonia, represent a single monophyletic lineage comprising several well supported groups. Mantel tests using control region data revealed a strong positive relationship when geographic distance was modeled according to a scenario of marine dispersal. (r = 0.69, P = 0.055). By contrast, direct distance between regions was poorly correlated with genetic distance (r = -0.05, P = 0.463). Hierarchical AMOVAs using mtDNA revealed that pooling samples according to historical (pre-LGM) oceanic drainage (Pacific vs. Atlantic) explained approximately four times more variance than pooling them into present-day drainage (15.6% vs. 3.7%). Further post-hoc AMOVA tests revealed additional genetic structure between populations east and west of the Chilean Coastal Cordillera (coastal vs. interior). Overall female effective population size appears to have remained relatively constant until roughly 0.5 Ma when population size rapidly increased several orders of magnitude [100× (60×-190×)] to reach contemporary levels. Maximum likelihood analysis of nuclear alleles revealed a poorly supported gene tree which was paraphyletic with respect to mitochondrial-defined haplogroups. Conclusions First diversifying in the central/north-west region of Patagonia, G. maculatus extended its range into Argentina via the southern coastal regions that join the Pacific and Atlantic oceans. More recent gene flow between northern populations involved the most ancient and most derived lineages, and was likely facilitated by drainage reversal(s) during one or more cooling events of the late Pleistocene. Overall female effective population size represents the end result of a widespread and several hundred-fold increase over approximately 0.5 Ma, spanning several climatic fluctuations of the Pleistocene. The minor influence of glacial cycles on the genetic structure and diversity of G. maculatus likely reflects the access to marine refugia during repeated bouts of global cooling. Evidence of genetic structure that was detected on a finer scale between lakes/rivers is most likely the result of both biological attributes (i.e., resident non-migratory behavior and/or landlocking and natal homing in diadromous populations), and the Coastal Cordillera as a dispersal barrier. PMID:20211014

  12. Isolation Driven Divergence in Osmoregulation in Galaxias maculatus (Jenyns, 1848) (Actinopterygii: Osmeriformes)

    PubMed Central

    Ruiz-Jarabo, Ignacio; Oyarzún, Ricardo; Fuentes, Juan; Poulin, Elie; Bertrán, Carlos; Vargas-Chacoff, Luis

    2016-01-01

    Background Marine species have colonized extreme environments during evolution such as freshwater habitats. The amphidromous teleost fish, Galaxias maculatus is found mainly migrating between estuaries and rivers, but some landlocked populations have been described in lakes formed during the last deglaciation process in the Andes. In the present study we use mtDNA sequences to reconstruct the historical scenario of colonization of such a lake and evaluated the osmoregulatory shift associated to changes in habitat and life cycle between amphidromous and landlocked populations. Results Standard diversity indices including the average number of nucleotide differences (Π) and the haplotype diversity index (H) indicated that both populations were, as expected, genetically distinctive, being the landlocked population less diverse than the diadromous one. Similarly, pairwise GST and NST comparison detected statistically significant differences between both populations, while genealogy of haplotypes evidenced a recent founder effect from the diadromous stock, followed by an expansion process in the lake. To test for physiological differences, individuals of both populations were challenged with a range of salinities from 0 to 30 ppt for 8 days following a period of progressive acclimation. The results showed that the landlocked population had a surprisingly wider tolerance to salinity, as landlocked fish survival was 100% from 0 to 20 ppt, whereas diadromous fish survival was 100% only from 10 to 15 ppt. The activity of ATPase enzymes, including Na+/K+-ATPase (NKA), and H+-ATPase (HA) was measured in gills and intestine. Activity differences were detected between the populations at the lowest salinities, including differences in ATPases other than NKA and HA. Population differences in mortality are not reflected in enzyme activity differences, suggesting divergence in other processes. Conclusions These results clearly demonstrate the striking adaptive changes of G. maculatus osmoregulatory system, especially at hyposmotic environments, associated to a drastic shift in habitat and life cycle at a scale of a few thousand years. PMID:27168069

  13. Salinity-dependent mechanisms of copper toxicity in the galaxiid fish, Galaxias maculatus.

    PubMed

    Glover, Chris N; Urbina, Mauricio A; Harley, Rachel A; Lee, Jacqueline A

    2016-05-01

    The euryhaline galaxiid fish, inanga (Galaxias maculatus) is widely spread throughout the Southern hemisphere occupying near-coastal streams that may be elevated in trace elements such as copper (Cu). Despite this, nothing is known regarding their sensitivity to Cu contamination. The mechanisms of Cu toxicity in inanga, and the ameliorating role of salinity, were investigated by acclimating fish to freshwater (FW), 50% seawater (SW), or 100% SW and exposing them to a graded series of Cu concentrations (0-200μgL(-1)) for 48h. Mortality, whole body Cu accumulation, measures of ionoregulatory disturbance (whole body ions, sodium (Na) influx, sodium/potassium ATPase activity) and ammonia excretion were monitored. Toxicity of Cu was greatest in FW, with mortality likely resulting from impaired Na influx. In both FW and 100% SW, ammonia excretion was significantly elevated, an effect opposite to that observed in previous studies, suggesting fundamental differences in the effect of Cu in this species relative to other studied fish. Salinity was protective against Cu toxicity, and physiology seemed to play a more important role than water chemistry in this protection. Inanga are sensitive to waterborne Cu through a conserved impairment of Na ion homeostasis, but some effects of Cu exposure in this species are distinct. Based on effect concentrations, current regulatory tools and limits are likely protective of this species in New Zealand waters. PMID:26966874

  14. Allocreadium pichi n. sp. (Trematoda: Allocreadiidae) in Galaxias maculatus (Osteichthyes: Galaxiidae) from Lake Moreno in Patagonia (Argentina).

    PubMed

    Flores, Verónica R; Brugni, Norma; Ostrowski de Núñez, Margarita

    2004-07-01

    Allocreadium pichi n. sp. (Trematoda: Allocreadiidae) is described from the intestine of Galaxias maculatus (Osteichthyes: Galaxiidae) from Moreno Lake in Patagonia, Argentina. This species is distinguished from A. patagonicum Shimazu, Urawa & Coria, 2000, the other species recorded in the area, by its smaller body size, the diagonal position of the testes and different ratios of the suckers, testes and cirrus-sac in relation to body size. In addition, the synonymy of A. patagonicum with Polylekithum percai Ostrowski de Núñez, Brugni & Viozzi, 2000 is proposed herein. PMID:15218369

  15. Do environmental differences between lakes in northwestern Argentinean Patagonia affect the infection of Philureter trigoniopsis (monogenea) in Galaxias maculatus (osmeriformes)?

    PubMed

    Viozzi, G P; Semenas, L G

    2009-02-01

    Philureter trigoniopsis is the only parasite found in the ureters and urinary bladder of Galaxias maculatus in Patagonian Andean lakes. The dynamics of this endoparasitic monogenean were studied in Lake Gutiérrez, a body of water with scarce shoreline vegetation, where the host has an annual cycle of migration to the deep pelagic zone of the lake. To compare variations of the infection related to differences between lakes, G. maculatus specimens were sampled monthly with baited traps from September 1998 to November 1999 in Lake Moreno, which is an oligotrophic body of water with emergent shoreline vegetation and where the fish do not migrate to the deep pelagic areas of the lake. In addition, data for summer infections of P. trigoniopsis from 10 Andean Patagonian lakes that differ in aquatic vegetation, depth, and area were compared. In Lake Moreno prevalence of P. trigoniopsis showed a seasonal pattern, with 1-yr-old fish exhibiting the highest values of prevalence and mean intensity. Negative correlations between water temperature and prevalence and between age of fish and abundance were found. Our results suggest that age of fish may be the main factor structuring the distribution of P. trigoniosis in populations of G. maculatus. At the regional level the relationship between the infection and the characteristics of the lakes was also observed, with prevalence and mean intensity of P. trigoniopsis in G. maculatus higher in large deep lakes without macrophytes. PMID:18576893

  16. Impact of a caged-trout farm on parasites of Galaxias maculatus in Lake Moreno, southern Argentina.

    PubMed

    Revenga, Jorge E; Torres, Patricio F; Baiz, Miguel

    2005-06-01

    The present study was conducted to determine the impact of a caged-trout farm on the helminth parasites of the wild fish puyen chico (Galaxias maculatus) in Lake Moreno, southern Argentina. Samples of water, fish (G. maculatus), and snails (Heleobia hatcheri) were taken at 4 sampling stations in January 2001. Wild fish were parasitized by 8 helminth species, all of which are endemic in the region; therefore, the farm did not introduce any helminth parasite to G. maculatus. Fish captured near the farm were not infected by the digenean Steganoderma szidati, whereas the abundance of the digenean Acanthostomoides apophalliformis in these fish was significantly lower than that in fish captured away from the farm. This lower abundance may be explained by the absence in this area of the snail H. hatcheri, the parasite's first intermediate host, because of the effect of sediments and ammonium produced by the farm. To our knowledge, this is the first study in the Americas linking fish-farm pollution to helminth parasites in wild fish. PMID:16108574

  17. A new genus of Cystidicolid nematode from the stomach of Galaxias maculatus (Osmeriformes: Galaxiidae) in Patagonia (Argentina).

    PubMed

    Brugni, Norma L; Viozzi, Gustavo P; Fernández, María V; Vega, Rocío M

    2009-02-01

    During a parasitological survey of Galaxias maculatus (Jenyns) from Patagonian Andean Lakes, specimens of a new species of nematode were collected from the stomach of fish and studied by light and scanning electron microscopy. This species is described as the only member of a newly proposed genus of Cystidicolidae by having oral opening dorsoventrally elongated, 2 lateral pseudolabia, 4 cephalic papillae, stoma (vestibule) elongated, esophagus divided into anterior muscular and posterior glandular sections, and caudal alae in males. Placonema n. gen. (Habronematoidea, Cystidicolidae) is characterized by the combination of the following features: oral opening dorsoventrally elongated demarcated by 4 sclerotized plates and 2 well-developed pseudolabia projected to the buccal cavity, each pseudolabium with conspicuous, conical, anterior protuberances. Four cephalic papillae and deirids simple. Male with caudal alae, area rugosa absent, 4 pairs of preanal papillae, unpaired papilla present on anterior cloacal lip, and 6 pairs of postanal papillae. Larvigerous eggs without filaments. Placonema pataguense n. gen. n. sp. infects the stomach of G. maculatus from Lake Patagua (Patagonia, Argentina) and is the first species of Cystidicolidae described from G. maculatus. PMID:18652524

  18. Steganoderma szidati n. sp. (Trematoda: Zoogonidae) from Galaxias maculatus (Jenyns) and G. platei Steindachner in Patagonia, Argentina.

    PubMed

    Viozzi, G; Flores, V; Ostrowski de Núñez, M

    2000-07-01

    Steganoderma szidati n. sp. is described from the intestine of two freshwater fishes, Galaxias maculatus and G. platei (Galaxiidae), from Andean lakes in Patagonia, Argentina. This freshwater zoogonid species fits in the genus Steganoderma (sensu Bray, 1987) because of the length of the caeca and the position of the vitelline follicles. The new species is characterised by possessing 6-13 vitelline follicles situated between the anterior margin of the ventral sucker and the posterior margin of the testis. The gonads are in the anterior hindbody and the ovary is anterior to the right testis. The cirrus has two conspicuous spines at its distal end, and the seminal vesicle always exhibits a constriction. The excretory vesicle never reaches the level of the posterior margin of the testes. PMID:10845652

  19. Extended incubation affects larval morphology, hatching success and starvation resistance in a terrestrially spawning fish, Galaxias maculatus (Jenyns 1842).

    PubMed

    Semmens, D; Swearer, S E

    2011-10-01

    The effect of extended incubation (delayed hatching) on larval morphology in the terrestrially spawning common galaxias Galaxias maculatus was investigated by inducing larvae to hatch 1 and 2 weeks after the normal 2 week incubation period. After 1 week of extended incubation, larvae were larger (longer in standard length, L(S), and greater in body depth) compared to controls (larvae that experienced normal incubation durations). After 2 weeks of extended incubation, larvae were smaller (shorter in L(S) and smaller in body depth) than larvae that experienced 1 week of extended incubation. Furthermore, eye area increased while yolk-sac size decreased monotonically with increasing incubation duration. These results suggest that larvae experiencing long periods of extended incubation are using somatic tissue to meet their metabolic demands. Larvae that experienced 2 weeks of extended incubation succumbed to starvation sooner than control larvae, but hatching success was not significantly different. Temperature mediated the effect of extended incubation on the morphology of larvae at hatching, most likely, through its effects on developmental rate and efficiency of yolk utilization. This study demonstrates some of the consequences of terrestrial spawning with extended incubation, which will assist in determining why this intriguing behaviour has evolved several times in a diverse range of taxa. PMID:21967585

  20. Extreme intraspecific mitochondrial DNA sequence divergence in Galaxias maculatus (Osteichthys: Galaxiidae), one of the world's most widespread freshwater fish.

    PubMed

    Waters, J M; Burridge, C P

    1999-02-01

    Biogeographic controversies surrounding the widespread freshwater fish, Galaxias maculatus, were addressed with DNA sequence data. Mitochondrial cytochrome b and 16S rRNA sequences were obtained from representatives of six populations of this species. Substantial levels of cytochrome b (maximum 14.6%) and 16S rRNA sequence divergence (maximum 6.0%) were detected between western Pacific (Tasmania-New Zealand) and South American (Chile-Falkland Islands) haplotypes. A considerable level of divergence was also detected between Tasmanian and New Zealand haplotypes (maximum 5.1%) and within and among Chilean and Falkland Island G. maculatus (maximum 3. 8%). The phylogenetic structure of haplotypes conflicts with the accepted pattern of continental fragmentation. Molecular clock calibrations suggest that haplotype divergences postdate the fragmentation of Gondwana. These findings point to marine dispersal rather than ancient vicariance as an explanation for the wide distribution. The phylogenetic structure of South American haplotypes was not consistent with their geographic distribution. We consider factors such as population divergence, population size, dispersal, secondary contact, and philopatry as potential causes of the high level of mtDNA nucleotide diversity in this species. PMID:10082606

  1. Population dynamics of Philureter trigoniopsis (Monogenea: Ancyrocephalinae) from urinary organs of Galaxias maculatus (Osmeriformes: Galaxiidae) in a cold temperate Andean Patagonian lake (Argentina).

    PubMed

    Viozzi, Gustavo P; Semenas, Liliana G; Gutiérrez, Pablo

    2005-12-01

    Philureter trigoniopsis parasitizes the ureters and urinary bladder of Galaxias maculatus in Patagonian Andean lakes. To investigate factors associated with variation in the prevalence and intensity of this monogenean, fish were sampled periodically over 2 yr in Lake Gutiérrez. Prevalence and mean intensity are higher in smaller fishes than in larger ones. A seasonal pattern was observed, with peak recruitment and peak mean intensity occurring in early spring (September), followed by lows in late summer (January-February). Galaxias maculatus length classes are spatially segregated due to seasonal migrations, so the annual infection cycle is characterized by higher prevalence and intensity from late winter to early summer in the smaller fish from the deep zone of the lake. PMID:16539018

  2. Contrasting Genetic Structure and Diversity of Galaxias maculatus (Jenyns, 1848) Along the Chilean Coast: Stock Identification for Fishery Management.

    PubMed

    González-Wevar, Claudio; Salinas, Pilar; Hüne, Mathias; Segovia, Nicolás; Vargas-Chacoff, Luis; Oda, Esteban; Poulin, Elie

    2015-01-01

    Galaxias maculatus (Pisces: Galaxiidae) commonly known as "puye" has a disjunct distribution along the Southern Hemisphere including landlocked and migratory populations at latitudes over 30°S in South America, Australia, Tasmania, and New Zealand. Chilean artisanal fishery of G. maculatus has become less important as a resource due to multiple factors including overexploitation, pollution, introduction of predators, and competitors. At the same time, the current conservation status of the species in Chile is still uncertain. Here, we used mtDNA control region sequences (925bp) to investigate main patterns of genetic diversity and structure in populations from 2 biogeographic areas along the Chilean coast. Extremely high levels of genetic diversity characterize the species, suggesting a low amount of influence of the last glacial cycle over its demography compared with other studies in freshwater and marine South American fishes. However, we recognized contrasting genetic patterns between the Intermediate Area (between 30°S and 42°S) and the Magellanic Province (between 42°S and 56°S). On the one hand, over a narrow geographical range (<200 km) each Intermediate Area estuarine population constitutes a different genetic unit. On the other hand, the Magellanic populations of the species exhibited low levels of differentiation in an area extending for more than 500 km. Such differences may be a consequence of different coastal configurations, oceanographic regimes, and Quaternary glacial histories. Finally, our results support the existence of different stock units for G. maculatus and this information should be integrated in future management strategies and aquaculture programs for this species. PMID:26245779

  3. Philureter trigoniopsis, a new genus and species (Dactylogyridae, Ancyrocephalinae) from the ureters and urinary bladder of Galaxias maculatus (Osmeriformes: Galaxiidae) in Patagonia (Argentina).

    PubMed

    Viozzi, G P; Gutiérrez, P A

    2001-04-01

    The monotypic Philureter n. gen. (Ancyrocephalinae; Dactylogyridae) is proposed to accommodate Philureter trigoniopsis n. sp. with the following features: presence of a cuplike ventral haptor armed with 14 hooks and 2 anchor/bar complexes; dorsal pair of anchors poorly defined and variable in shape, 1 frequently absent; tandem, intercecal gonads, testis bilaterally lobulated. Philureter trigoniopsis n. sp. is described from the ureters and urinary bladder of Galaxias maculatus (Jenyns, 1842) (Osmeriformes) in Patagonian Andean lakes, Argentina. PMID:11318570

  4. Infections by helminth parasites in "puyenes", Galaxias maculatus (Galaxiidae, Salmoniformes), from Southern Argentina with special reference to Tylodelphys barilochensis (Digenea, Platyhelminthes).

    PubMed

    Revenga, J; Scheinert, P

    1999-01-01

    The occurrence of Tylodelphys barilochensis, Acanthostomoides apophalliformis, Contracaecum sp. and Camallanus corderoi infecting Galaxias maculatus ("puyenes") was quantified for the first time in Lake Nahuel Huapi, southern Argentina. T. barilochensis was recorded in this lake for the first time. The role of G. maculatus population in transmission of parasites to the salmonids is more important for Contracaecum sp. (prevalence 14-34%) and A. apophalliformis (prevalence 30-54%) than for C. corderoi (prevalence 6-8%). The absence of Diphyllobothrium spp. in samples shows that the G. maculatus population does not play any role in the life cycles of these important zoonotic parasites. The sex of the host had no effect on T. barilochensis abundance. Statistical differences in T. barilochensis abundance between "puyenes" of the same size class between sampling stations and positive correlation between prevalence of infected snails and T. barilochensis abundance in fish suggest that different stocks have been sampled. Factors influencing T. barilochensis abundance are discussed. PMID:10464401

  5. A new genus of dactylogyrid from the gills of Galaxias maculatus (Osmeriformes: Galaxiidae) in Maullín Basin, Patagonia, Chile.

    PubMed

    Viozzi, Gustavo P; Marin, Sandra L; Carvajal, Juan; Brugni, Norma; Mancilla, Melinka

    2007-06-01

    During a parasitological survey of Galaxias maculatus (Jenyns, 1842) in the Maullín Basin (Chilean Patagonia), specimens of a new species of Monogenea were collected from the gills. This species is described as the only member of a proposed new genus, Inserotrema n. gen. (Dactylogyridae, Ancyrocephalinae), characterized by similar hooks with 2 subunits, overlapping gonads, coiled cirrus with counterclockwise rings, articulated accessory piece formed by 2 parts, a needlelike sclerite threading the distal part of the MCO, and a sclerotized midventral vagina. This new genus is proposed for dactylogyrids from gills of galaxiids (Galaxiidae). Inserotrema puyei n. sp. infects gills of G. maculatus from Llanquihue Lake, Maullín River, and Maullín Estuary. This is the first species of Ancyrocephalinae described from gills of a galaxiid. PMID:17626345

  6. Differential expression of Na+, K(+)-ATPase α-1 isoforms during seawater acclimation in the amphidromous galaxiid fish Galaxias maculatus.

    PubMed

    Urbina, Mauricio A; Schulte, Patricia M; Bystriansky, Jason S; Glover, Chris N

    2013-04-01

    Inanga (Galaxias maculatus) is an amphidromous fish with a well-known capacity to withstand a wide range of environmental salinities. To investigate the molecular mechanisms facilitating acclimation of inanga to seawater, several isoforms of the Na(+), K(+)-ATPase ion transporter were identified. This included three α-1 (a, b and c), an α-2 and two α-3 (a and b) isoforms. Phylogenetic analysis showed that the inanga α-1a and α-1b formed a clade with the α-1a and α-1b isoforms of rainbow trout, while another clade contained the α-1c isoforms of these species. The expression of all the α-1 isoforms was modulated after seawater exposure (28‰). In gills, the expression of the α-1a isoform was progressively down-regulated after seawater exposure, while the expression of the α-1b isoform was up-regulated. The α-1c isoform behaved similarly to the α-1a, although changes were less dramatic. Physiological indicators of salinity acclimation matched the time frame of the changes observed at the molecular level. A 24-h osmotic shock period was highlighted by small increases in plasma osmolality, plasma Na(+) and a decrease in muscle tissue water content. Thereafter, these values returned close to their pre-exposure (freshwater) values. Na(+), K(+)-ATPase activity showed a decreasing trend over the first 72 h following seawater exposure, but activity increased after 240 h. Our results indicate that inanga is an excellent osmoregulator, an ability that is conferred by the rapid activation of physiological and molecular responses to salinity change. PMID:23142926

  7. Phylogeography in Galaxias maculatus (Jenyns, 1848) along Two Biogeographical Provinces in the Chilean Coast.

    PubMed

    González-Wevar, Claudio A; Salinas, Pilar; Hüne, Mathias; Segovia, Nicolás I; Vargas-Chacoff, Luis; Astorga, Marcela; Cañete, Juan I; Poulin, Elie

    2015-01-01

    Major geologic and climatic changes during the Quaternary exerted a major role in shaping past and contemporary distribution of genetic diversity and structure of aquatic organisms in southern South America. In fact, the northern glacial limit along the Pacific coast, an area of major environmental changes in terms of topography, currents, and water salinity, represents a major biogeographic transition for marine and freshwater species. We used mitochondrial DNA sequences (D-loop) to investigate the consequences of Quaternary glacial cycles over the pattern of genetic diversity and structure of G. maculatus (Pisces: Galaxiidae) along two biogeographical provinces in the Chilean coast. Extreme levels of genetic diversity and strong phylogeographic structure characterize the species suggesting a low amount of influence of the last glacial cycle over its demography. However, we recognized contrasting patterns of genetic diversity and structure between main biogeographical areas here analyzed. Along the Intermediate Area (38°-41° S) each estuarine population constitutes a different unit. In contrast, Magellanic populations (43°-53° S) exhibited low levels of genetic differentiation. Contrasting patterns of genetic diversity and structure recorded in the species between the analyzed biogeographic areas are consistent with the marked differences in abiotic factors (i.e., different coastal configurations, Quaternary glacial histories, and oceanographic regimes) and to inherent characteristics of the species (i.e., salt-tolerance, physiology, and reproductive behavior). PMID:26161896

  8. Phylogeography in Galaxias maculatus (Jenyns, 1848) along Two Biogeographical Provinces in the Chilean Coast

    PubMed Central

    González-Wevar, Claudio A.; Salinas, Pilar; Hüne, Mathias; Segovia, Nicolás I.; Vargas-Chacoff, Luis; Astorga, Marcela; Cañete, Juan I.; Poulin, Elie

    2015-01-01

    Major geologic and climatic changes during the Quaternary exerted a major role in shaping past and contemporary distribution of genetic diversity and structure of aquatic organisms in southern South America. In fact, the northern glacial limit along the Pacific coast, an area of major environmental changes in terms of topography, currents, and water salinity, represents a major biogeographic transition for marine and freshwater species. We used mitochondrial DNA sequences (D-loop) to investigate the consequences of Quaternary glacial cycles over the pattern of genetic diversity and structure of G. maculatus (Pisces: Galaxiidae) along two biogeographical provinces in the Chilean coast. Extreme levels of genetic diversity and strong phylogeographic structure characterize the species suggesting a low amount of influence of the last glacial cycle over its demography. However, we recognized contrasting patterns of genetic diversity and structure between main biogeographical areas here analyzed. Along the Intermediate Area (38°–41° S) each estuarine population constitutes a different unit. In contrast, Magellanic populations (43°–53° S) exhibited low levels of genetic differentiation. Contrasting patterns of genetic diversity and structure recorded in the species between the analyzed biogeographic areas are consistent with the marked differences in abiotic factors (i.e., different coastal configurations, Quaternary glacial histories, and oceanographic regimes) and to inherent characteristics of the species (i.e., salt-tolerance, physiology, and reproductive behavior). PMID:26161896

  9. Ailinella mirabilis gen. n., sp. n. (eucestoda: pseudophyllidea) from Galaxias maculatus (Pisces: Galaxiidae) in the Andean-Patagonian region of Argentina.

    PubMed

    de Pertierra, Alicia A Gil; Semenas, Liliana G

    2006-12-01

    Ailinella gen. n. (Pseudophyllidea: Triaenophoridae) is proposed to accommodate Ailinella mirabilis sp. n. from Galaxias maculatus (Jenyns, 1842), a freshwater fish inhabiting the Andean lakes in Argentinean Patagonia. Ailinella belongs to the Triaenophoridae because it has a marginal genital pore, a follicular vitelline gland, and a ventral uterine pore. The new genus can be distinguished from other triaenophorids by the following combination of characters: a small body size, a low number of proglottides, which are longer than wide, a truncated pyramidal to globular scolex, a rectangular apical disc, presence of the neck, lack of internal longitudinal musculature separating the cortex from the medulla, testes distributed in one central field surrounding the ovary laterally and posteriorly, the vagina predominantly anterior to the cirrus sac, vitelline follicles circum-medullary, the genital pores post-equatorial, a saccate uterus, and operculate eggs. Blade-like spiniform microtriches were present on all tegument surfaces, and tumuli on all surfaces of the scolex and the anterior surface of the neck. Microtriches were characterized according to their size and density, and tumuli according to their size, inter-tumulus distance and density. Ailinella mirabilis is the first cestode described from G. maculatus and the second triaenophorid species recorded from a South American freshwater fish. PMID:17256203

  10. Should I stay or should I go?: Physiological, metabolic and biochemical consequences of voluntary emersion upon aquatic hypoxia in the scaleless fish Galaxias maculatus.

    PubMed

    Urbina, Mauricio A; Glover, Chris N

    2012-12-01

    Hypoxia represents a significant challenge to most fish, forcing the development of behavioural, physiological and biochemical adaptations to survive. It has been previously shown that inanga (Galaxias maculatus) display a complex behavioural repertoire to escape aquatic hypoxia, finishing with the fish voluntarily emerging from the water and aerially respiring. In the present study we evaluated the physiological, metabolic and biochemical consequences of both aquatic hypoxia and emersion in inanga. Inanga successfully tolerated up to 6 h of aquatic hypoxia or emersion. Initially, this involved enhancing blood oxygen-carrying capacity, followed by the induction of anaerobic metabolism. Only minor changes were noted between emersed fish and those maintained in aquatic hypoxia, with the latter group displaying a higher mean cell haemoglobin content and a reduced haematocrit after 6 h. Calculations suggest that inanga exposed to both aquatic hypoxia and air reduced oxygen uptake and also increased anaerobic contribution to meet energy demands, but the extent of these changes was small compared with hypoxia-tolerant fish species. Overall, these findings add to previous studies suggesting that inanga are relatively poorly adapted to survive aquatic hypoxia. PMID:22645056

  11. Relationship between fish size and metabolic rate in the oxyconforming inanga Galaxias maculatus reveals size-dependent strategies to withstand hypoxia.

    PubMed

    Urbina, Mauricio A; Glover, Chris N

    2013-01-01

    The relationship between metabolic rate and body size in animals is unlikely to be a constant but is instead shaped by a variety of intrinsic (i.e., physiological) and extrinsic (i.e., environmental) factors. This study examined the effect of environmental oxygen tension on oxygen consumption as a function of body mass in the galaxiid fish, inanga (Galaxias maculatus). As an oxyconformer, this fish lacks overt intrinsic regulation of oxygen consumption, eliminating this as a factor affecting the scaling relationship at different oxygen tensions. The relationship between oxygen consumption rate and body size was best described by a power function, with an exponent of 0.82, higher than the theoretical values of 0.66 or 0.75. The value of this exponent was significantly altered by environmental P(O2), first increasing as P(O2) decreased and then declining at the lowest P(O2) tested. These data suggest that the scaling exponent is species specific and regulated by extrinsic factors. Furthermore, the external P(O2) at which fish lost equilibrium was related to fish size, an effect explained by the scaling of anaerobic capacity with fish mass. Therefore, although bigger fish were forced to depress aerobic metabolism more rapidly than small fish when exposed to progressive hypoxia, they were better able to enact anaerobic metabolism, potentially extending their survival in hypoxia. PMID:24241070

  12. Infection patterns of Tylodelphys barilochensis and T. crubensis (Trematoda: Diplostomatidae) metacercariae in Galaxias maculatus (Osmeriformes: Galaxiidae) from two Patagonian lakes and observations on their geographical distribution in the southern Andean region, Argentina.

    PubMed

    Flores, Verónica; Liliana, Semenas

    2002-12-01

    In the Patagonian Andean region, 2 species of diplostomatids parasitize the brains of Galaxias maculatus. The purpose of this study was to evaluate seasonal variation, spatial variation, and association with host age in the transmission of Tylodelphys barilochensis and T. crubensis in several oligotrophic lakes in Argentinian Patagonia. Fishes were captured monthly in Lake Gutiérrez and bimonthly in Lake Escondido. One summer or autumn sample was also taken in several other Patagonian lakes. Infection parameters were calculated and compared using nonparametric tests. The 2 species co-occurred in most of the sampled lakes, with high values of prevalence and mean intensity. In Lake Gutiérrez and Lake Escondido, the intensity of both diplostomatid species did not show significant differences between sexes and co-varied with host length. All age classes were infected; maximum prevalence values were reached before maximum mean intensity values in the 1-yr age class. A seasonal pattern of prevalence and mean intensity of the 2 parasite species with autumn mean intensity values differing significantly from those of the other seasons was evident only in Lake Gutiérrez. PMID:12537107

  13. Fifteen from one: a revision of the Galaxias olidus Günther, 1866 complex (Teleostei, Galaxiidae) in south-eastern Australia recognises three previously described taxa and describes 12 new species.

    PubMed

    Raadik, Tarmo A

    2014-01-01

    The systematics of the Galaxias olidus hyper-species complex from freshwater habitats in south-eastern, mainland Australia is revised. Galaxias olidus Günther 1866 is redescribed, Galaxias fuscus Mack 1936 and Galaxias ornatus Castelnau 1873, previously synonymised with G. olidus (sensu lato), are reinstated as valid taxa and redescribed, and 12 taxa are described as new: Galaxias aequipinnis sp. nov., Galaxias arcanus sp. nov., Galaxias brevissimus sp. nov., Galaxias gunaikurnai sp. nov., Galaxias lanceolatus sp. nov., Galaxias longifundus sp. nov., Galaxias mcdowalli sp. nov., Galaxias mungadhan sp. nov., Galaxias oliros sp. nov., Galaxias supremus sp. nov., Galaxias tantangara sp. nov., and Galaxias terenasus sp. nov. These species are morphologically similar and, whilst there is extensive overlap in meristic counts and morphometric characters, each can be diagnosed by unique combinations of characters, including allozyme loci and colour pattern; morphological diagnosis is improved greatly if based on freshly formalin-fixed material. Galaxias schomburgkii Peters 1868, Galaxias bongbong Macleay 1881, Galaxias kayi Ramsay & Ogilby 1886 and Galaxias oconnori Ogilby 1912 are retained as junior synonyms of G. olidus (sensu stricto). The types for Galaxias findlayi Macleay 1882 are lost and no specimens matching its description were collected or examined from the Mt. Kosciuszko region; it is also currently retained as a junior synonym of Galaxias olidus s.s. The species G. terenasus sp. nov. and G. arcanus sp. nov. are the most morphologically specialised in the complex and G. olidus s.s remains the most morphologically variable species. It also remains the most widespread taxon, though its previously known distribution is reduced, particularly in the south-west of its range. Nine species are narrow-range endemics, known from one, or only a few, locations, and these restricted distributions most probably reflect the fragmentation and reduction of former ranges caused by the effects of alien salmonids. Eleven species are of conservation concern, most are considered critically endangered. PMID:25543673

  14. Activity of the ovarian germinal epithelium in the freshwater catfish, Pimelodus maculatus (Teleostei: Ostariophysi: Siluriformes): germline cysts, follicle formation and oocyte development.

    PubMed

    Quagio-Grassiotto, Irani; Grier, Harry; Mazzoni, Talita Sarah; Nóbrega, Rafael Henrique; de Arruda Amorim, João Paulo

    2011-11-01

    Distinct types of oogonia are found in the germinal epithelium that borders the ovarian lamellae of Pimelodus maculatus: A-undifferentiated, A-differentiated and B-oogonia. This is similar to the situation observed for spermatogonia in the vertebrate testis. The single A-undifferentiated oogonia divide by mitosis giving rise to A-groups of single differentiated oogonia, each enclosed by epithelial cells that are prefollicle cells. Subsequently, the single A-differentiated oogonia proliferate to generate B-oogonia that are interconnected by cytoplasmic bridges, hence, forming germline cysts. The prefollicle cells associated with them also divide. Within the germline cysts, B-oogonia enter meiosis becoming oocytes. Meiotic prophase and early folliculogenesis occur within the germline cysts. During folliculogenesis, prefollicle cells grow between the oocytes, encompassing and individualizing each of them. The intercellular bridges disappear, and the germline cysts are broken down. Next, a basement membrane begins to form around the nascent follicle, separating an oocyte and its associated prefollicle cells from the cell nest. Folliculogenesis is completed when the oocyte and the now follicle cells are totally encompassed by a basement membrane. Cells derived from the ovarian stroma encompass the newly-formed ovarian follicle, and become the theca, thereby completing the formation of the follicle complex. Follicle complexes remain attached to the germinal epithelium as they share a portion of basement membrane. This attachment site is where the oocyte is released during ovulation. The postovulatory follicle complex is continuous with the germinal epithelium as both are supported by a continuous basement membrane. The findings in P. maculatus reinforce the hypothesis that ovarian follicle formation represents a conserved process throughout vertebrate evolution. PMID:21630323

  15. Captura de galaxias enanas en cúmulos de galaxias

    NASA Astrophysics Data System (ADS)

    Bassino, L. P.; Muzzio, J. C.; Pérez, J.

    Se investiga el proceso de captura de galaxias enanas por parte de galaxias gigantes, en presencia de un campo externo causado por materia distribuída y otras galaxias pertenecientes al cúmulo en que se produce el fenómeno. Se trabaja mediante simulaciones numéricas, generando condiciones iniciales típicas de cúmulos de galaxias y representando, con un espectro de masas, a las galaxias más masivas y, como partículas de prueba, a las enanas. Se sigue la evolución del sistema empleando un código de integración de N-cuerpos y se analizan los resultados para determinar las capturas de galaxias enanas.

  16. Modelo de galaxia disco

    NASA Astrophysics Data System (ADS)

    Ledesma, M.; Mosconi, M.

    El objetivo de este trabajo es estudiar la formación de galaxias anillo, a través de simulaciones numéricas. En el estudio numérico es necesario construir el modelo de una galaxia disco normal, en condición de equilibrio estable, que se ajuste a los parámetros observacionales disponibles de estos objetos. En dicho modelo se considera la galaxia constituída por un halo de materia oscura, un bulge y el disco propiamente dicho. A partir de perfiles de densidad obtenidos de las observaciones, se lleva a cabo la distribución espacial de las partículas, a través del ``Método del rechazo". La asignación de velocidades se realiza considerando que las partículas del disco están aproximadamente en equilibrio rotacional, y se agregan dispersiones de velocidad de acuerdo con el parámetro de Toomre Q=1.5.

  17. Galaxias australes con núcleo doble

    NASA Astrophysics Data System (ADS)

    Gimeno, G.; Díaz, R.; Carranza, G.

    Se estudia una muestra de galaxias australes con núcleo doble a partir de una búsqueda extensiva en la literatura. Se analizan las características morfológicas, fotométricas y espectroscópicas de la muestra. Para algunas galaxias se han realizado observaciones con el espectrógrafo multifunción (EMF) de la Estación Astrofísica de Bosque Alegre a partir de las cuales se determinaron parámetros cinemáticos.

  18. Estudio de la galaxia peculiar NGC 1487

    NASA Astrophysics Data System (ADS)

    Agüero, E. L.; Paolantonio, S.; Gunthardt, G.

    La galaxia peculiar NGC 1487, cuya morfología sugiere un evento de ``merging" o interacción próxima, es estudiada en base a material observacional espectroscópico y fotométrico obtenido en el CASLEO. Mediante técnicas espectrofotométricas standards se determinan las principales características espectrales, los mecanismos de excitación actuantes, las condiciones físicas y las velocidades radiales de las estructuras conspicuas de la galaxia. Por otra parte, usando imágenes directas en las bandas B, V, R e I, se obtienen distribuciones detalladas de los colores B-V, V-R y R-I y detalles de su morfología.

  19. Possible sub-glacial eruptions in the Galaxias Quadrangle, Mars

    NASA Astrophysics Data System (ADS)

    Mouginis-Mark, Peter J.; Wilson, Lionel

    2016-03-01

    We have identified several landforms in the Galaxias Quadrangle of Mars (MTM 35217), 33.0-35.5°N, 216.0-218.0°W which are consistent with this area having been covered by an ancient ice sheet concurrent with volcanic eruptions. Volcanic activity was initiated by the intrusion of several large dikes measuring ∼50-100 m wide and protruding up to ∼35 m above the present-day surface. These dikes appear to have originated from Elysium Planitia ∼600 km to the SE. In one instance, a dike (at an elevation of -3750 m) appears to have produced a subglacial mound (referred to here as "Galaxias Mons 2") that evolved into an extrusive eruption and produced copious volumes of melt water that carved an outflow channel that extends almost 300 km to the north. At a lower elevation (-3980 m), a second putative dike may have failed to break the surface of the ice sheet and formed Galaxias Mons as a laccolithic intrusion. We numerically model the formation of Galaxias Mons and find that at least 200 m of ice may once have existed at this latitude at the time of the dike intrusions. Such a conclusion supports the idea that enigmatic small domes in the area may be pingoes. Collectively, these observations suggest that the previous interpretations for the origin of near-by Hrad Vallis as a sub-aerial eruption may need to be revised.

  20. "Nuestra Galaxia" & "Adler En Español"

    NASA Astrophysics Data System (ADS)

    Salgado, Jose F.

    2007-05-01

    "Nuestra Galaxia" is an Emmy-nominated weekly astronomy news segment and a collaboration between the Adler Planetarium & Astronomy Museum and Noticias Univision Chicago. The two-minute segment hosted by José Francisco Salgado covers astronomy news and topics, skywatching information as well as questions submitted by viewers. "Nuestra Galaxia" is part of an Adler initiative called "Adler en Español" which explores opportunities to interact with the Spanish-speaking community in the Chicago area which numbers more than one million people. Other Spanish-language components of this initiative include audio tours, courses, special programs, sky shows, and interactive exhibits. A review of these components, challenges encountered, and lessons learned so far are presented here.

  1. Movimientos peculiares de galaxias en el Universo cercano

    NASA Astrophysics Data System (ADS)

    Alonso, M. V.

    Se presenta un resumen de los resultados más importantes obtenidos en los últimos años sobre movimientos peculiares en el Universo Cercano. En el escenario de inestabilidad gravitacional, el campo de velocidades peculiares es una herramienta muy útil para estimar las fluctuaciones en la distribución de masa que generan los movimientos observados. Esta aproximación puede, además, ser utilizada para poner restricciones al espectro de potencia de la masa, a la relación entre las distribuciones de galaxias y de materia y al valor del parámetro de densidad cosmológico, Ω, a grandes escalas. Son además presentados una reconstrucción preliminar de los campos de densidad de masa y velocidades peculiares en el universo cercano usando nuevas medidas de distancias obtenidas con la relación Dn - σ, para una muestra de galaxias elípticas y lenticulares. Dos subestructuras prominentes son encontradas en la región del Gran Atractor, que corresponden a los complejos de Centaurus y Pavo--Indus. Estos últimos, junto a los complejos de Perseus--Piscis y Cetus parecen ser importantes estructuras que determinan el flujo global. El patrón obtenido a través de una muestra de galaxias elípticas muestra variaciones con respecto al obtenido por galaxias espirales. Estos nuevos resultados muestran una coherencia menor en el flujo global, cuando son comparados con resultados obtenidos anteriormente.

  2. Población de galaxias de baja luminosidad en cúmulos

    NASA Astrophysics Data System (ADS)

    Valotto, C. A.; Muriel, H.; Moore, B.; García Lambas, D.

    En este trabajo se discute sobre la presencia de un exceso de galaxias de baja luminosidad en medios de alta densidad de galaxias y la posibilidad de que los halos de galaxias cD puedan ser formados a partir de galaxias en cúmulos ricos, los cuales muestran una función de luminosidad (FL) con el extremo débil plano. Se analizaron muestras de cúmulos cercanos obtenidas a partir de los catálogos de Abell y X-ray Sample of Bright Clusters. Los resultados obtenidos muestran que los cúmulos de galaxias que tienen emisión en rayos X detectada poseen una FL plana (α ≈ -1.2), consistente con los valores encontrados para las galaxias de campo. En cambio, los cúmulos de galaxias identificados a partir de distribuciones bidimensionales de galaxias que no tienen su contraparte en rayos X, muestran una FL con una pendiente pronunciada en el extremo débil (α ≈ -1.6). Se examinaron además, los posibles efectos debido a la presencia de una galaxia central dominante sobre el extremo débil de la FL. Se analizaron muestras de acuerdo a la clasificación Bautz-Morgan dividiendo en las submuestras I,I-II y II, II- III, III. Las FL resultantes para ambas muestras son indistinguibles. Nuestros resultados son consistentes con la hipótesis de que los efectos de proyección en cúmulos identificados en dos dimensiones pueden producir un exceso artificial de galaxias de baja luminosidad.

  3. Complete mitochondrial genome of Lateolabrax maculatus.

    PubMed

    Liu, Kai; Duan, Jinrong; Xu, Dongpo; Zhou, Yanfeng; Zhang, Minying; Fang, Dian; Xu, Pao

    2016-07-01

    In this study, we sequence the complete mitochondrial genome of Lateolabrax maculatus. This mitochondrial genome is 16,597 bp in length, encoding 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs and a non-coding control region as found in other vertebrates, with the gene synteny identical to those of typical vertebrates. Control region (D-Loop), of 929 bp in length, is located between tRNA(Pro) and tRNA(Phe). The overall base composition of the heavy strand shows T 25.9%, C 29.5%, A 27.3% and G 17.3%, with an AT bias of 53.2%. PMID:26075475

  4. POPULATION GENETIC STRUCTURE OF ANOPHELES MACULATUS IN THAILAND

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anopheles (Cellia) maculatus Theobald is a major malaria vector in southern Thailand and peninsular Malaysia, and previous studies on the population genetics of this mosquito suggested that mountain ranges reduced gene flow among some populations. In this study we examine the genetic variance among...

  5. Tubulated bodies in teleost (Pimelodus maculatus) endothelial cells.

    PubMed

    Ferri, S; Sesso, A

    1983-01-01

    In the present report tubulated granules are described for the first time in a freshwater teleost (Pimelodus maculatus) endothelial cells. Some ultrastructural characteristics as well as the localization and distribution suggest that tubulated bodies represent the teleost counterpart of the Weibel-Palade bodies described in other animal classes. PMID:6639042

  6. Fotometría de grupos compactos de galaxias: Shakhbazian 37, 45, 166, 331 y 362

    NASA Astrophysics Data System (ADS)

    Campos, J. M.; Calderón, J. H.; Gimeno, N. G.; Díaz, R. J.

    Continuando con la fotometría CCD de Grupos de Galaxias Compactos de Shakhbazyan (SCGG) en este trabajo se presentan nuevos resultados preliminares sobre los grupos Shakbazyan 37, 45, 166, 331 y 362. EL objeto del proyecto es contribuir al estudio de las propiedades físicas de tales grupos y contribuir a las bases de datos para mejora de las estadísticas. Los datos fueron adquiridos con el Telescopio JKT del Observatorio Norte Europeo. El análisis de las imágenes en las bandas I y B como del índice de color B-I permitió reidentificar las galaxias catalogadas, resultando las mismas muy enrojecidas y verificando que predominan las galaxias tempranas, resultados consistentes con los obtenidos para otros grupos y por otros autores.

  7. Growth and reproduction of the highfin grouper Epinephelus maculatus.

    PubMed

    Rhodes, K L; Taylor, B M; Hernandez-Ortiz, D; Cuetos-Bueno, J

    2016-05-01

    Highfin grouper Epinephelus maculatus sampled in Chuuk, Micronesia, exhibited a moderate growth rate and a relatively short life span compared to other epinephelids of a similar size. Combined gonad and otolith analysis provide preliminary evidence that the species conforms to a protogynous sexual pattern. Mean total length at maturity for females was 308 mm with first age at maturity 2·8 years for females and 4 years for males, which differs from other regional studies. Based on the gonado-somatic index and microscopic analysis of gonads, E. maculatus in Chuuk have a 4 month spawning season (January to April) that corresponds with seasonal lows in sea surface water temperature and overlaps with that of other aggregating epinephelids. The estimated von Bertalanffy growth factor (K) was 0·51 year(-1) , while total mortality was 0·34 year(-1) . Current management for E. maculatus in Chuuk includes a January to May catch, sale and export ban, which overlaps with its reproductive season. The effectiveness of these arrangements will require on-going monitoring to determine whether alternative management strategies are required to ensure population persistence. PMID:27021483

  8. Dispersión de velocidades en cúmulos de galaxias

    NASA Astrophysics Data System (ADS)

    Muriel, H.; García Lambas, D.; Quintana, H.; Infante, L.

    Se ha estudiado la dinámica de galaxias en cúmulos en base a una muestra de aproximadamente 4000 galaxias con estimas de velocidad radial pertenecientes a 40 cúmulos. Se desarrolló un algoritmo para identificar sub-estructuras del tipo ``grupos de galaxias". Una vez eliminada este tipo de sub-estructura se computaron los perfiles radiales de dispersión de velocidades (VDP) para los 40 cúmulos de galaxias. Dada las características de la muestra, fue posible estimar el VDP hasta grandes distancias del centro del cúmulo llegando en algunos casos hasta 7 Mpc-1. Los resultados indican que el 65% de los cúmulos presentan un VDP plano a grandes radios consistente con el modelo isotermo. Estos resultados son discutidos en el marco de las recientes controversias suscitadas respecto de la dinámica de los cúmulos vía los perfiles de temperaturas de cúmulos derivados de la emisión en rayos-X.

  9. Curva de rotación de la Galaxia Eso 321-25

    NASA Astrophysics Data System (ADS)

    Díaz, R.; Carranza, G.; Ahumada, J.; Arreguine, V.

    Se presenta la curva de rotación de esta galaxia, generada a partir de espectros obtenidos con el Espectrógrafo Multifunción del telescopio de 1.54 m de Bosque Alegre. El análisis de las curvas de velocidad radial obtenidas muestra que el núcleo no coincide con el centro de simetría de las mismas, lo que es consistente con el aspecto morfológico exhibido por la galaxia en imágenes de banda ancha. En estas últimas, el núcleo muestra una estructura peculiar y no coincidiría con el centro geométrico del disco aparente. Los flujos relativos de líneas (Hα /[NII]λ 6583 y [SII]λ 6731/λ 6716) indicarían niveles de excitación y densidad electrónica normales en regiones HII, aún en la zona nuclear. Este trabajo forma parte de un programa de estudio de cinemática, excitación y densidad electrónica del gas ionizado en galaxias peculiares del Atlas de Galaxias Australes de Sérsic.

  10. Geologic map of the Galaxias quadrangle (MTM 35217) of Mars

    USGS Publications Warehouse

    De Hon, Rene A.; Mouginis-Mark, Peter J.; Brick, Eugene E.

    1999-01-01

    The Galaxias region (MTM 35217) is one of a series of 1:500,000-scale science study areas on Mars sponsored by NASA's Planetary Geology and Geophysics Program. Situated near the northern limit of lava flows associated with Elysium Mons, this region includes a mixture of volcanic and nonvolcanic terrains. The region is also of interest for the fluvial systems that originate along the distal margins of the Elysium lava flows. Resolution of Viking Orbiter images used to prepare the base map ranges from 40 to 160 m/pixel. High-resolution frames (40 to 80 m/pixel) are found in the southeastern part of the map area and along the north edge of the quadrangle, but over half the quadrangle is included in medium-resolution frames (150 m/pixel). Two 8 m/pixel, very high resolution scenes are available (see fig. 1). Interpretation is complicated by variable resolution and sun angles that vary from east to west illumination on different images. Mapping methods and principles are adapted from those developed for lunar photogeologic mapping by Shoemaker and Hackman (1962), refined by Wilhelms (1972), and successfully applied by many workers to a variety of planetary surfaces. Mapping units are distinguished by topography and texture and are ranked by relative age on the basis of superposition and transection relations. Material units are assigned to time-stratigraphic systems defined by Scott and Carr (1978) and Tanaka (1986). This area is included within earlier maps that used Mariner 9 images at 1:5,000,000 scale (Elston, 1979) and globally at 1:25,000,000 scale (Scott and Carr, 1978). Regional maps based on the much higher resolutions of Viking Orbiter allowed more detailed discrimination of materials by Greeley and Guest (1987) at 1:15,000,000 scale and Tanaka and others (1992) at 1:5,000,000 scale. Some map units on this 1:500,000-scale map correspond to, or are partially equivalent to, units on the larger scale maps of Greeley and Guest (1987) and Tanaka and others (1992). Established terminology is used where feasible, but the scale of this map requires that some new units be introduced and that some previous terminology be redefined. Photogeologic methods are limited; therefore, more than one geologic explanation is given for some material units that do not readily lend themselves to an unequivocal interpretation.

  11. Temperature induced transformation of teleost (Pimelodus maculatus) epidermal cells.

    PubMed

    Ferri, S

    1982-01-01

    Superficial epidermal cells of the teleost Pimelodus maculatus show modifications after heat exposure (36 degrees C) for 3 days. Heat treatment affects the arrangement of cytoplasmic filaments resulting in the disappearance of the microridges. The fish maintained at 36 degrees C during 3 days show modifications in the cytoplasmic organization of their superficial epidermal cells. The most conspicuous alterations are: apparition of lysosomes (including autolysosomes), hypertrophy of the GOLGI complexes, disappearance of the RER, and modifications in the nuclear envelope. Epidermal cells maintained at 36 degrees C for 10 days are transformed into horny-like cells. The differences and resemblances with keratinized cells of terrestrial vertebrates are described and discussed. PMID:6891352

  12. Electron microscopic study of teleost (Pimelodus maculatus) pancreatic islet cells.

    PubMed

    Ferri, S; Stipp, A C

    1984-01-01

    The endocrine pancreas of the freshwater teleost Pimelodus maculatus was studied by electron microscopy. Based on the granule morphology 2 cell types were described: Secretory granules of type I cells are rounded, nearly completely filling the limiting membranous sac which measures from 120 to 150 nm in diameter; the type II granules are also rounded and measure from 220 to 270 nm in diameter; they consist of an eccentrical electron dense core separated from the limiting membrane by a wide electron lucent halo. These characteristics are correlated with those found in other teleosts. PMID:6370782

  13. Cúmulos globulares como trazadores de bimodalidad estelar en galaxias cD

    NASA Astrophysics Data System (ADS)

    Forte, J. C.

    Se muestra que tanto la forma de los perfiles de brillo como de color observados en dos galaxias arquetípicas de tipo cD (NGC 1399 y NGC 4486) son compatibles con la presencia de poblaciones estelares bi-modales que comparten la misma distribución espacial y composición química de las familias dominantes de cúmulos globulares asociadas con ellas. El modelo resultante también predice una variación de la frecuencia específica de los cúmulos como función del radio galactocéntrico. Se discute este resultado en el contexto de una variedad de escenarios astrofísicos que intentan describir la formación de galaxias cD.

  14. Influence of substrate and relative humidity on the efficacy of three entomopathogenic fungi for the hide beetle, Dermestes maculatus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dermestes maculatus is carrion feeder that is also a pest of poultry houses, museums, silkworm culture, and many stored foods. The Hypocreales, Beauveria bassiana, Metarhizium anisopliae, and Isaria fumosorosea, were tested for efficacy against D. maculatus larvae on concrete, plastic, leather, and ...

  15. The mimetic repertoire of the spotted bowerbird Ptilonorhynchus maculatus

    NASA Astrophysics Data System (ADS)

    Kelley, Laura A.; Healy, Susan D.

    2011-06-01

    Although vocal mimicry in songbirds is well documented, little is known about the function of such mimicry. One possibility is that the mimic produces the vocalisations of predatory or aggressive species to deter potential predators or competitors. Alternatively, these sounds may be learned in error as a result of their acoustic properties such as structural simplicity. We determined the mimetic repertoires of a population of male spotted bowerbirds Ptilonorhynchus maculatus, a species that mimics predatory and aggressive species. Although male mimetic repertoires contained an overabundance of vocalisations produced by species that were generally aggressive, there was also a marked prevalence of mimicry of sounds that are associated with alarm such as predator calls, alarm calls and mobbing calls, irrespective of whether the species being mimicked was aggressive or not. We propose that it may be the alarming context in which these sounds are first heard that may lead both to their acquisition and to their later reproduction. We suggest that enhanced learning capability during acute stress may explain vocal mimicry in many species that mimic sounds associated with alarm.

  16. Why Do Female Callosobruchus maculatus Kick Their Mates?

    PubMed Central

    van Lieshout, Emile; McNamara, Kathryn B.; Simmons, Leigh W.

    2014-01-01

    Sexual conflict is now recognised as an important driver of sexual trait evolution. However, due to their variable outcomes and effects on other fitness components, the detection of sexual conflicts on individual traits can be complicated. This difficulty is exemplified in the beetle Callosobruchus maculatus, where longer matings increase the size of nutritious ejaculates but simultaneously reduce female future receptivity. While previous studies show that females gain direct benefits from extended mating duration, females show conspicuous copulatory kicking behaviour, apparently to dislodge mating males prematurely. We explore the potential for sexual conflict by comparing several fitness components and remating propensity in pairs of full sibling females where each female mated with a male from an unrelated pair of full sibling males. For one female, matings were terminated at the onset of kicking, whereas the other’s matings remained uninterrupted. While fecundity (number of eggs) was similar between treatments, uninterrupted matings enhanced adult offspring numbers and fractionally also longevity. However, females whose matings were interrupted at the onset of kicking exhibited an increased propensity to remate. Since polyandry can benefit female fitness in this species, we argue that kicking, rather than being maladaptive, may indicate that females prefer remating over increased ejaculate size. It may thus be difficult to assess the presence of sexual conflict over contested traits such as mating duration when females face a trade off between direct benefits gained from one mating and indirect benefits from additional matings. PMID:24752530

  17. Talisia esculenta lectin and larval development of Callosobruchus maculatus and Zabrotes subfasciatus (Coleoptera: Bruchidae).

    PubMed

    Macedo, Maria Ligia R; das Graças Machado Freire, Maria; Novello, José Camillo; Marangoni, Sérgio

    2002-06-01

    Bruchid larvae cause major losses in grain legume crops throughout the world. Some bruchid species, such as the cowpea weevil and the Mexican bean weevil, are pests that damage stored seeds. Plant lectins have been implicated as antibiosis factors against insects, particularly the cowpea weevil, Callosobruchus maculatus. Talisia esculenta lectin (TEL) was tested for anti-insect activity against C. maculatus and Zabrotes subfasciatus larvae. TEL produced ca. 90% mortality to these bruchids when incorporated in an artificial diet at a level of 2% (w/w). The LD(50) and ED(50) for TEL was ca. 1% (w/w) for both insects. TEL was not digested by midgut preparations of C. maculatus and Z. subfasciatus. The transformation of the genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops. PMID:12049788

  18. The complete mitochondrial genome sequence of Diptychus maculatus Steindachner (Cypriniformes: Cyprinidae).

    PubMed

    He, Dekui; Liang, Yangyang; Li, Chunhua; Wei, Chaojun; Chen, Yifeng

    2016-09-01

    Diptychus maculatus (Cypriniformes: Cyprinidae), the sole species of genus Diptychus, is an economically important freshwater fish widely distributed in Asia. In this study, we first sequenced the complete mitochondrial genome of D. maculatus. The genome is 16,835 bp in length, consisting of 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes as well as 2 non-coding regions: origin of light-strand replication (OL) and control region (D-loop). The gene composition and order are identical with most bony fishes. The overall nucleotide composition of the heavy strand is 27.7% A, 26.7% T, 26.5% C and 19.1% G. The mitogenome data would be useful for further genetics studies, phylogenetic analysis, and resource protection of D. maculatus and phylogenetic analysis of Schizothoracine fishes. PMID:25774947

  19. Chaos formation by sublimation of volatile-rich substrate: Evidence from Galaxias Chaos, Mars

    NASA Astrophysics Data System (ADS)

    Pedersen, G. B. M.; Head, J. W.

    2011-01-01

    Galaxias Chaos deviates significantly from other chaotic regions due to the lack of associated outflow channels, lack of big elevation differences between the chaos and the surrounding terrain and due to gradual trough formation. A sequence of troughs in different stages is observed, and examples of closed troughs within blocks suggest that the trough formation is governed by a local stress field rather than a regional stress field. Moreover, geomorphic evidence suggests that Galaxias Chaos is capped by Elysium lavas, which superpose an unstable subsurface layer that causes chaotic tilting of blocks and trough formation. Based on regional mapping we suggest a formation model, where Vastitas Borealis Formation embedded between Elysium lavas is the unstable subsurface material, because gradual volatile loss causes shrinkage and differential substrate movement. This process undermines the lava cap, depressions form and gradually troughs develop producing a jigsaw puzzle of blocks due to trough coalescence. Observations of chaos west of Elysium Rise indicate that this process might have been widespread along the contact between Vastitas Borealis Formation and Elysium lavas. However, the chaotic regions have probably been superposed by Elysium/Utopia flows to the NW of Elysium Rise, and partly submerged with younger lavas to the west.

  20. Phylogeographical population structure of tiger quolls Dasyurus maculatus (Dasyuridae: Marsupialia), an endangered carnivorous marsupial.

    PubMed

    Firestone, K B; Elphinstone, M S; Sherwin, W B; Houlden, B A

    1999-10-01

    Tiger quolls, Dasyurus maculatus, are the largest carnivorous marsupials still extant on the mainland of Australia, and occupy an important ecological niche as top predators and scavengers. Two allopatric subspecies are recognized, D.m. gracilis in north Queensland, and D.m. maculatus in the southeast of the mainland and Tasmania. D.m. gracilis is considered endangered while D.m. maculatus is listed as vulnerable to extinction; both subspecies are still in decline. Phylogeographical subdivision was examined to determine evolutionarily significant units (ESUs) and management units (MUs) among populations of tiger quolls to assist in the conservation of these taxa. Ninety-three tiger quolls from nine representative populations were sampled from throughout the species range. Six nuclear microsatellite loci and the mitochondrial DNA (mtDNA) control region (471 bp) were used to examine ESUs and MUs in this species. We demonstrated that Tasmanian tiger quolls are reciprocally monophyletic to those from the mainland using mtDNA analysis, but D.m. gracilis was not monophyletic with respect to mainland D.m. maculatus. Analysis of microsatellite loci also revealed significant differences between the Tasmanian and mainland tiger quolls, and between D.m. gracilis and mainland D.m. maculatus. These results indicate that Tasmanian and mainland tiger quolls form two distinct evolutionary units but that D.m. gracilis and mainland D.m. maculatus are different MUs within the same ESU. The two marker types used in this study revealed different male and female dispersal patterns and indicate that the most appropriate units for short-term management are local populations. A revised classification and management plan are needed for tiger quolls, particularly in relation to conservation of the Tasmanian and Queensland populations. PMID:10583825

  1. Modification of microridge pattern in teleost (Pimelodus maculatus) epidermal cells induced by NaCl.

    PubMed

    Ferri, S

    1983-01-01

    When NaCl is added to the aqueous environment, the fingerprint-like pattern showed by microridges of epidermal superficial cells of the teleost Pimelodus maculatus is modified. This modification probably occurs consequently the rearrangement of cytoplasmic filaments. PMID:6884732

  2. Reproduction and embryogenesis of the mandi-amarelo catfish, Pimelodus maculatus (Pisces, Pimelodidae), in captivity.

    PubMed

    Arantes, F P; Borçato, F L; Sato, Y; Rizzo, E; Bazzoli, N

    2013-02-01

    To study reproduction and embryogenesis, Pimelodus maculatus specimens were kept in captivity and captured bimonthly during 1 year. Gonads samples (211 specimens) were collected and submitted to routine histological techniques. Pimelodus maculatus prepared to reproduce when water temperature was high, and even reached advanced maturation but did not spawn in captivity. Spent fish gonads were not documented, and atretic follicles were frequent (60%) in late maturation females. When then submitted to hypophysation, 70% of the females responded positively to hormonal treatment. Oocyte extrusion occurred 8 h after a second hormonal injection at 26°C. The fertilisation rate was 65.1 ± 9.2% at 24°C. Recently spawned oocytes of P. maculatus were spherical, non-adhesive, yellow in colour, with an average diameter of 1113.92 ± 37.02 μm and covered by a thick gelatinous layer. Blastopore closure occurred 7 h and 30 min after fertilisation. Embryonic development was completed within 18 h after fertilisation. The results of this work provide important knowledge for the handling and cultivation of not only P. maculatus, but other species of potential value for fish culture. PMID:22612443

  3. Variation in vertebral number and its morphological implication in Galaxias platei.

    PubMed

    Barriga, J P; Milano, D; Cussac, V E

    2013-11-01

    Variation in the vertebral number of the puyen grande Galaxias platei was examined for specimens from 22 localities that span the entire distribution range of the species (from 40° to 55° S). The mean vertebral number (NMW ) increases towards high latitudes, i.e. Jordan's rule is applicable to this species. Owing to the wide geographic variation of the species, not only in latitude but also in altitude, the most explicative variable for NMW was mean winter air temperature, showing negative dependence. Morphological data suggest that the increment in vertebral number lies in the pre-pelvic region of the trunk and in the caudal region, but not in the segment between pelvic-fin insertion and the origin of the anal fin. As these alterations in body shape have important consequences for hydrodynamics and swimming performance, vertebral number variation in G. platei also holds implications for both individual and population fitness. PMID:24124792

  4. New cystidicolid species (Nematoda) from Galaxias platei (Osmeriformes: Galaxiidae) in Patagonian freshwater environments.

    PubMed

    Brugni, Norma L; Viozzi, Gustavo P

    2008-08-01

    During a parasitological survey of Galaxias platei Steindachner, 1898, from Patagonian Andean Lakes, a new species of Cystidicolidae was found in the stomach of fish. The new species was described using light and scanning electron microscopy; the species has characteristics of Ascarophis and is distinguishable from other species by a combination of the following features: well-developed pseudolabia with T-shaped inner extensions, bifurcate deirids, small ratio GE:ME, small left spicule, small ratio LS:RS, and larvigerous eggs with thick and fine filaments in both poles. Intraspecific variation in the morphology of larvigerous eggs was studied. This is the first species of Ascarophis described from freshwater fishes. PMID:18576739

  5. The complete mitochondrial genome of Platysmacheilus nudiventris (Teleostei, Cyprinidae, Gobioninae).

    PubMed

    Shao, Ke; Xiong, Mei-Hua; Yan, Shu-Xiang; Li, Wei-Tao

    2016-05-01

    The complete mitochondrial genome of Platysmacheilus nudiventris (Teleostei, Cyprinidae, Gobioninae), an endemic Chinese cyprinid fish, was first determined by DNA sequencing based on the PCR fragments. The total length of the mitochondrial genome is 16,603 bp, including 22 transfer RNA genes, 2 ribosomal RNA genes, 13 protein-coding genes and a non-coding control region (D-loop). The overall-based composition is 30.2% A, 26.9% T, 16.7% G and 26.1% C, with high A+T content (57.1%). The results will provide useful data for further studies on species identification, evolutionary and population genetic studies of P. nudiventris and its related species. PMID:25329268

  6. The complete mitochondrial genome of Rhinogobio typus (Teleostei, Cyprinidae, Gobioninae).

    PubMed

    Yan, Shu-xiang; Xiong, Mei-hua; Zhu, Bin; Tian, Hua; Liao, Xiao-lin; Shao, Ke

    2016-01-01

    In the present study, the complete mitochondrial genome sequence of Rhinogobio typus (Teleostei, Cyprinidae, Gobioninae) was obtained using a PCR-based method. The total length of the mitochondrial genome is 16,608 bp, including 22 transfer RNA genes, 2 ribosomal RNA genes, 13 protein-coding genes, and a non-coding control region (D-loop), which is similar to that observed in many other reported fishes. The overall-based composition is 31.3% A, 26.6% T, 15.9% G and 26.2% C, with high A + T content (57.9%). These results will provide a useful tool for species identification, evolutionary and population genetic studies of R. typus and its related species. PMID:24779592

  7. First report of the characterization of the pathophysiological mechanisms caused by the freshwater catfish Pimelodus maculatus (order: Siluriformes).

    PubMed

    Sarmiento, Beatriz Elena; Rangel, Marisa; Gonçalves, Jacqueline Coimbra; Pereira, Lilibete; Rego, Solange; Campos, Leandro Ambrósio; Haddad, Vidal; Mortari, Márcia Renata; Schwartz, Elisabeth F

    2015-07-01

    Injuries caused by aquatic animals in Brazil in most cases are provoked by marine and freshwater catfish. Pimelodus maculatus is a freshwater catfish very common in Brazilian basins that causes frequent accidents mainly amongst fishermen, and whose venom characteristics and pathological mechanisms of the venom are poorly known. In the present study for the first time, we have characterized the main pathophysiological mechanisms associated with the clinical manifestation (pain, local inflammation and edema) of the envenomations caused by P. maculatus crude venom. It was estimated that the crude venom of one P. maculatus stinger contains approximately 100 μg of protein, likely the quantity involved in the envenomation. P. maculatus crude venom induced marked nociceptive and edematogenic effects and caused vascular permeability alterations at doses from 30 to 100 μg/animal. Additionally, P. maculatus crude venom caused a decrease in the contraction force in in situ frog heart, did not cause hemorrhage or alterations in clotting times (prothrombin time and activated partial thromboplastin time), but induced significant changes in the levels of CK and its isoenzyme CK-MB in mice. In the present work, we present a correlation between the effects obtained experimentally and the main symptoms observed in the human accidents provoked by P. maculatus. PMID:25911957

  8. El origen de las galaxias en modelos jerárquicos de formación de la estructura

    NASA Astrophysics Data System (ADS)

    Navarro, J. F.

    En esta charla presentaré una revisión de los modelos corrientes de formación de galaxias. En particular, haré énfasis en el origen de la gran variedad de morfologías galácticas y de las correlaciones entre las propiedades estructurales de discos y esferoides, todo dentro del contexto cosmológico jerárquico provisto por teorías como la de materia oscura fría. En este tipo de teorías las correlaciones observadas entre la luminosidad, velocidad de rotación, momento angular, y tamaño de galaxias son el resultado de la falta de escalas naturales en el proceso de formación de los halos de materia oscura que dichas galaxias habitan. Simulaciones numéricas que incorporan efectos gravitacionales, hidrodinámicos y de formación estelar ilustran estas ideas y demuestran las dificultades que aquejan a modelos donde tanto discos como esferoides son el resultado final de una secuencia de fusiones de sistemas protogalácticos.

  9. Modification of postmortem wounds by Dermestes maculatus (Coleoptera: Dermestidae) activity: A preliminary study.

    PubMed

    Zanetti, Noelia I; Ferrero, Adriana A; Centeno, Néstor D

    2015-11-01

    The purpose of this analysis was to evaluate the effects of insect activity on hacking trauma which was inflicted with a small cleaver and a razor blade under controlled conditions. Three pig hooves were each subjected to a blow with a small cleaver and a cut with a razor blade prior to insect exposure. We used Dermestes maculatus DeGeer 1774 species. These beetles made principally depressions and destruction on both wounds, and bites were observed on the edges of the wounds. As time passed and insects fed and refuge, chop marks were deformed and disappeared, taking this less than a month. Thus, D. maculatus could mask postmortem wounds and probably premortem wounds, and so the cause of death. PMID:26352289

  10. Lima bean (Phaseolus lunatus) seed coat phaseolin is detrimental to the cowpea weevil (Callosobruchus maculatus).

    PubMed

    Moraes, R A; Sales, M P; Pinto, M S; Silva, L B; Oliveira, A E; Machado, O L; Fernandes, K V; Xavier-Filho, J

    2000-02-01

    The presence of phaseolin (a vicilin-like 7S storage globulin) peptides in the seed coat of the legume Phaseolus lunatus L. (lima bean) was demonstrated by N-terminal amino acid sequencing. Utilizing an artificial seed system assay we showed that phaseolin, isolated from both cotyledon and testa tissues of P. lunatus, is detrimental to the nonhost bruchid Callosobruchus maculatus (F) (cowpea weevil) with ED50 of 1.7 and 3.5%, respectively. The level of phaseolin in the seed coat (16.7%) was found to be sufficient to deter larval development of this bruchid. The expression of a C. maculatus-detrimental protein in the testa of nonhost seeds suggests that the protein may have played a significant role in the evolutionary adaptation of bruchids to legume seeds. PMID:10657058

  11. Mitochondrial and allozyme genetics of incipient speciation in a landlocked population of Galaxias truttaceus (Pisces: Galaxiidae).

    PubMed

    Ovenden, J R; White, R W

    1990-03-01

    Galaxias truttaceus is found in coastal rivers and streams in south-eastern Australia. It spawns at the head of estuaries in autumn and the larvae spend 3 months of winter at sea before returning to fresh water. In Tasmania there are landlocked populations of G. truttaceus in a cluster of geologically young lakes on the recently glaciated Central Plateau. These populations have no marine larval stage and spawn in the lakes in spring. Speciation due to land locking is thought to be a frequent occurrence within Galaxias. To investigate the nature of the speciation event which may be occurring within lake populations of G. truttaceus we studied the mitochondrial DNA (mtDNA) and allozyme diversity of both lake and stream populations. Using the presence or absence of restriction sites recognized by 13 six-base restriction endonucleases, we found 58 mtDNA haplotypes among 150 fish collected from 13 Tasmanian and one south-east Australian mainland stream populations. The most parsimonious network relating the haplotypes by site loss or gain was starlike in shape. We argue that this arrangement is best explained by selection upon slightly beneficial mutations within the mitochondrial genome. Gene diversity analysis under Wright's island model showed that the populations in each drainage were not genetically subdivided. Only two of these stream haplotypes were found among the 66 fish analyzed from four lake populations. Despite the extreme lack of mtDNA diversity in lake populations, the observed nuclear DNA heterozygosity of 40 lake fish (0.10355) was only slightly less than that of 82 stream fish (0.11635). In the short time (3000-7000 years) that the lake fish have been landlocked, random genetic drift in a finite, stable-sized population was probably not responsible for the lack of mtDNA diversity in the lake populations. We infer the lake populations have probably experienced at least one, severe, but transitory bottleneck possibly induced by natural selection for life-history characters essential for survival in the lacustrine habitat. If speciation is occurring in the landlocked populations of G. truttaceus, then it may be driven by genetic transilience. PMID:2155855

  12. Mitochondrial and Allozyme Genetics of Incipient Speciation in a Landlocked Population of Galaxias Truttaceus (Pisces: Galaxiidae)

    PubMed Central

    Ovenden, J. R.; White, RWG.

    1990-01-01

    Galaxias truttaceus is found in coastal rivers and streams in south-eastern Australia. It spawns at the head of estuaries in autumn and the larvae spend 3 months of winter at sea before returning to fresh water. In Tasmania there are landlocked populations of G. truttaceus in a cluster of geologically young lakes on the recently glaciated Central Plateau. These populations have no marine larval stage and spawn in the lakes in spring. Speciation due to land locking is thought to be a frequent occurrence within Galaxias. To investigate the nature of the speciation event which may be occurring within lake populations of G. truttaceus we studied the mitochondrial DNA (mtDNA) and allozyme diversity of both lake and stream populations. Using the presence or absence of restriction sites recognized by 13 six-base restriction endonucleases, we found 58 mtDNA haplotypes among 150 fish collected from 13 Tasmanian and one south-east Australian mainland stream populations. The most parsimonious network relating the haplotypes by site loss or gain was starlike in shape. We argue that this arrangement is best explained by selection upon slightly beneficial mutations within the mitochondrial genome. Gene diversity analysis under Wright's island model showed that the populations in each drainage were not genetically subdivided. Only two of these stream haplotypes were found among the 66 fish analyzed from four lake populations. Despite the extreme lack of mtDNA diversity in lake populations, the observed nuclear DNA heterozygosity of 40 lake fish (0.10355) was only slightly less than that of 82 stream fish (0.11635). In the short time (3000-7000 years) that the lake fish have been landlocked, random genetic drift in a finite, stable-sized population was probably not responsible for the lack of mtDNA diversity in the lake populations. We infer the lake populations have probably experienced at least one, severe, but transitory bottleneck possibly induced by natural selection for life-history characters essential for survival in the lacustrine habitat. If speciation is occurring in the landlocked populations of G. truttaceus, then it may be driven by genetic transilience. PMID:2155855

  13. Electron microscopic study of lymphocytes in a freshwater teleost (Pimelodus maculatus) epidermis.

    PubMed

    Ferri, S

    1983-01-01

    Small lymphocytes were identified in a freshwater teleost (Pimelodus maculatus) epidermis at the ultrastructural level. Although they were the most abundant, the medium and the large lymphocytes were also present. They were found at all levels of the epidermis, specially in small spaces between the cells of the basal layer. They appeared in contact only with filament-containing cells. Intercellular junctions, however, were never observed. They were negative to the histochemical test used to detect the present of acid phosphatase. PMID:6650847

  14. Electron microscope observations on the cytoplasmic granules of a freshwater teleost (Pimelodus maculatus) leucocyte.

    PubMed

    Ferri, S; Hernandez Blazquez, F J

    1987-01-01

    In the present study, a hitherto undescribed granule type in the leucocytes of the freshwater teleost Pimelodus maculatus is reported. This membrane bounded elliptic granule contains straight tubules measuring from 8 to 10 nm in diameter. Almost all granules present 1 or 2 electron dense inclusions more often than not with a geometrical form. A comparison with the granules found in Prochilodus scrofa leucocytes is made. PMID:3631529

  15. Repellent and fumigant toxicity of essential oil from Thymus persicus against Tribolium castaneum and Callosobruchus maculatus.

    PubMed

    Moharramipour, S; Taghizadeh, A; Meshkatalsadat, M H; Talebi, A A; Fathipour, Y

    2008-01-01

    Repellent and insecticidal activity of the essential oil extracted from Thymus persicus (Roniger ex Reach. F.) Jalas was evaluated against two stored-product beetles Tribolium castaneum (Herbst) and Callosobruchus maculatus (F.). Dry flowering aerial parts of the plant were subjected to hydro distillation using a modified Clevenger-type apparatus. The repellent and fumigant toxicity were tested against 1-7 days old adult beetles at 27 +/- 1 degrees C and 65 +/- 5% RH in dark condition. The repellency on C. maculatus and T. castaneum at highest concentration (2 microL/mL acetone) was 82.40% and 70.40% respectively. Fumigation bioassays showed that C. maculatus adults were significantly more susceptible (LC50 = 2.39 microL/L air) to the essential oil than T. castaneum adults (LC50 = 234.42 microL/L air). It could be concluded that T. persicus may have potential for applications in management of stored-product pests because of its safety, strong repellency and fumigant toxicity. PMID:19226805

  16. UVB-induced gene expression in the skin of Xiphophorus maculatus Jp 163 B☆

    PubMed Central

    Yang, Kuan; Boswell, Mikki; Walter, Dylan J.; Downs, Kevin P.; Gaston-Pravia, Kimberly; Garcia, Tzintzuni; Shen, Yingjia; Mitchell, David L.; Walter, Ronald B.

    2014-01-01

    Xiphophorus fish and interspecies hybrids represent long-standing models to study the genetics underlying spontaneous and induced tumorigenesis. The recent release of the Xiphophorus maculatus genome sequence will allow global genetic regulation studies of genes involved in the inherited susceptibility to UVB-induced melanoma within select backcross hybrids. As a first step toward this goal, we report results of an RNA-Seq approach to identify genes and pathways showing modulated transcription within the skin of X. maculatus Jp 163 B upon UVB exposure. X. maculatus Jp 163 B were exposed to various doses of UVB followed by RNA-Seq analysis at each dose to investigate overall gene expression in each sample. A total of 357 genes with a minimum expression change of 4-fold (p-adj < 0.05) were identified as responsive to UVB. The molecular genetic response of Xiphophorus skin to UVB exposure permitted assessment of; (1) the basal expression level of each transcript for each skin sample, (2) the changes in expression levels for each gene in the transcriptome upon exposure to increasing doses of UVB, and (3) clusters of genes that exhibit similar patterns of change in expression upon UVB exposure. These data provide a foundation for understanding the molecular genetic response of fish skin to UVB exposure. PMID:24556253

  17. The sensory basis of olfactory search behavior in banded kokopu ( Galaxias fasciatus).

    PubMed

    Baker, Cindy F; Montgomery, John C; Dennis, Todd E

    2002-08-01

    The sensory basis of olfactory search behavior was investigated in the banded kokopu, Galaxias fasciatus, using a flow tank. In the presence of a 2 cm s(-1) current flow, banded kokopu use both water current and chemical information to locate a food odor source. The superficial neuromasts of the lateral line system mediate the rheotactic component of the odor search. A physical block of one olfactory nostril did not affect the olfactory search strategy employed by banded kokopu in still water or in the presence of a current flow. Thus, there is no evidence that banded kokopu perform a bilateral comparison of the olfactory stimulus during their odor search. Previously, olfaction and gustation have been the only sensory systems shown to directly mediate orientation and movement towards odor sources in fish. The use of hydrodynamic cues by fish in location of an olfactory source has been previously proposed, but without direct experimental identification of the sensory systems employed. This study identifies the contributing roles of both olfactory and hydrodynamic sensory systems to the olfactory search repertoire of fish. PMID:12209343

  18. [In vitro effect of rainbow trout (Oncorhynchus mykiss) serum in Tylodelphys sp. (trematoda, Diplosromatidae) metacercariae].

    PubMed

    Olabuenaga, S

    2000-01-01

    Here, it has been described that normal fresh sera from rainbow trout (Oncorhynchus mykiss) were able to lyse Tylodelphys sp. metacercariae isolated from Galaxias maculatus (Jenyns, 1842) (Teleostei, Galaxiidae) brain. This effect was time dependent, and progressively increased since 1 h up to 18 h incubation. There were oscillations in the ability of different sera samples to lyse these parasites. Similar values were achieved with other salmonid sera, and also with normal human sera pool. The lytic activity was abolished by heat-inactivated sera, by zymosan treatment and by incubation in the presence of EDTA. However, the mean values obtained in the presence of EGTA-Mg++ did not significantly differ from those found with sera as a source of complement. The results of this study suggested the role of complement alternative pathway on Tylodephys sp. in vitro lysis, under our experimental conditions. PMID:11757418

  19. Preliminary Results on Evaluation of Chickpea, Cicer arietinum, Genotypes for Resistance to the Pulse Beetle, Callosobruchus maculatus

    PubMed Central

    Erle, F.; Ceylan, F.; Erdemir, T.; Toker, C.

    2009-01-01

    The chickpea, Cicer arietinum L. (Fabales: Fabaceae), seeds are vulnerable, both in the field and in storage, to attack by seed-beetles. Beetles of the genus Callosobruchus are major storage pests of chickpea crops and cause considerable economic losses. In the present study, a total of 11 chickpea genotypes including five ‘kabuli’ (Mexican white, Diyar, CA 2969, ILC 8617 and ACC 245) and six ‘desi’ chickpeas (ICC 1069, ICC 12422, ICC 14336, ICC 4957, ICC 4969 and ICC 7509) were evaluated for resistance to the pulse beetle Callosobruchus maculatus F. (Coleoptera: Bruchidae). Resistance was evaluated by measuring percent damage to seeds. Damage to seeds by C. maculatus was manifested by the round exit holes with the ‘flap’ of seed coat made by emerging adults. Of the 11 genotypes tested, only one (ICC 4969) exhibited a complete resistance to C. maculatus in both free-choice and no-choice tests; no seed damage was found over the test period. In general, the ‘desi’ chickpeas were more resistant to C. maculatus than the ‘kabuli’ chickpeas. Among the tested chickpea genotypes, only ICC 4969 can be used as a source of C. maculatus resistance in breeding programmes that could then be grown in organic cultivation free from pesticides. PMID:20050777

  20. 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

  1. Código árbol paralelizado para simulaciones astrofísicas. Experimentos de encuentros de galaxias compuestas

    NASA Astrophysics Data System (ADS)

    Viturro, H. R.; Carpintero, D. D.

    Se describe la implementación de un código árbol octal paralelizado desarrollado por los autores. Este código permite la integración del problema de N--cuerpos simultáneamente en varias computadoras (``cluster''), lo que permite desarrollar altas velocidades de cálculo. Se muestran los resultados de algunas integraciones de encuentros entre galaxias de disco con bulbo y halo, generadas mediante algoritmos no utilizados hasta el momento en este campo.

  2. Biting activity and host preference of the malaria vectors Anopheles maculatus and Anopheles sawadwongporni (Diptera: Culicidae) in Thailand.

    PubMed

    Muenworn, Vithee; Sungvornyothin, Sungsit; Kongmee, Monthathip; Polsomboon, Suppaluck; Bangs, Michael J; Akrathanakul, Pongthep; Tanasinchayakul, Somchai; Prabaripai, Atchariya; Chareonviriyaphap, Theeraphap

    2009-06-01

    Adult mosquitoes in the Anopheles maculatus group were surveyed from different regions of Thailand and five different species were morphologically identified, including Anopheles maculatus, Anopheles sawadwongporni, Anopheles notanandai, Anopheles dravidicus, and Anopheles willmori. Blood-feeding activity and host preference of two species, Anopheles maculatus and Anopheles sawadwongporni, were observed during a one-year period at Pu Teuy Village, Sai Yok District, Kanchanaburi Province, west-central Thailand. Both species were more prevalent during the wetter period of the year and each had a greater predilection to feed on cattle than humans. Primary feeding activity occurred between 20:00-23:00 and a smaller peak at 01:00-03:00. Findings are discussed relative to the importance of these two vectors for malaria transmission in Pu Teuy. PMID:20836806

  3. Albizia lebbeck Seed Coat Proteins Bind to Chitin and Act as a Defense against Cowpea Weevil Callosobruchus maculatus.

    PubMed

    Silva, Nadia C M; De Sá, Leonardo F R; Oliveira, Eduardo A G; Costa, Monique N; Ferreira, Andre T S; Perales, Jonas; Fernandes, Kátia V S; Xavier-Filho, Jose; Oliveira, Antonia E A

    2016-05-11

    The seed coat is an external tissue that participates in defense against insects. In some nonhost seeds, including Albizia lebbeck, the insect Callosobruchus maculatus dies during seed coat penetration. We investigated the toxicity of A. lebbeck seed coat proteins to C. maculatus. A chitin-binding protein fraction was isolated from seed coat, and mass spectrometry showed similarity to a C1 cysteine protease. By ELM program an N-glycosylation interaction motif was identified in this protein, and by molecular docking the potential to interact with N-acetylglucosamine (NAG) was shown. The chitin-binding protein fraction was toxic to C. maculatus and was present in larval midgut and feces but not able to hydrolyze larval gut proteins. It did not interfere, though, with the intestinal cell permeability. These results indicate that the toxicity mechanism of this seed coat fraction may be related to its binding to chitin, present in the larvae gut, disturbing nutrient absorption. PMID:27078512

  4. Differences in midgut serine proteinases from larvae of the bruchid beetles Callosobruchus maculatus and Zabrotes subfasciatus.

    PubMed

    Silva, C P; Terra, W R; Lima, R M

    2001-05-01

    Proteinase activities in the larval midguts of the bruchids Callosobruchus maculatus and Zabrotes subfasciatus were investigated. Both midgut homogenates showed a slightly acidic to neutral pH optima for the hydrolysis of fluorogenic substrates. Proteolysis of epsilon-aminocaproil-Leu-Cys(SBzl)-MCA was totally inhibited by the cysteine proteinase inhibitors E-64 and leupeptin, and was activated by 1.5 mM DTT in both insects, while hydrolysis of the substrate Z-ArgArg-MCA was inhibited by aprotinin and E-64, which suggests that it is being hydrolysed by serine and cysteine proteinases. Gel assays showed that the proteolytic activity in larval midgut of C. maculatus was due to five major cysteine proteinases. However, based on the pattern of E-64 and aprotinin inhibition, proteolytic activity in larval midgut of Z. subfasciatus was not due only to cysteine proteinases. Fractionation of the larval midgut homogenates of both bruchids through ion-exchange chromatography (DEAE-Sepharose) revealed two peaks of activity against Z-ArgArg-MCA for both bruchid species. The fractions from C. maculatus have characteristics of cysteine proteinases, while Z. subfasciatus has one non-retained peak of activity containing cysteine proteinases and another eluted in a gradient of 250-350 mM NaCl. The proteolytic activity of the retained peak is higher at pH 8.8 than at pH 6.0 and corresponds with a single peak that is active against N-p-tosyl-GlyGlyArg-MCA, and sensitive to 250 microM aprotinin (90% inhibition). The peak contains a serine proteinase which hydrolyzes alpha-amylase inhibitor 1 from the common bean (Phaseolus vulgaris). Arch. PMID:11317332

  5. Insecticidal Activity and Chemical Composition of the Morinda lucida Essential Oil against Pulse Beetle Callosobruchus maculatus

    PubMed Central

    Owolabi, Moses S.; Ogundajo, Akintayo L.; Ogunwande, Isiaka A.; Yusuff, Olaniyi K.; Flores-Fernandez, Karen Isabel; Flores-Fernandez, Jose Miguel

    2014-01-01

    Insecticidal activity of essential oil extracted from Morinda lucida was tested on pulse beetle Callosobruchus maculatus, which is a pest that causes serious damage to several pulses. The insecticidal activity was compared with two pesticides, Phostoxin and Primo-ban-20. 120 mixed sex adult C. maculatus were introduced, along with 30 g of cowpeas. Four concentrations (0.40, 0.20, 0.10, and 0.05 μg/mL) of the M. lucida essential oil, Phostoxin, and Primo-ban-20 were tested. Essential oil chemical composition was analyzed by GC-MS. M. lucida essential oil showed a high toxicological effect, producing 100% mortality after 72 hours at a dose of 0.20 μg/mL. M. lucida essential oil had a potent insecticidal activity (LC90 = 0.629 μg/mL) compared to both pesticides, Phostoxin (LC90 = 0.652 μg/mL) and Primo-ban-20 (LC90 = 0.726 μg/mL), at 24 h. The main compounds of the essential oil were the oxygenated monoterpenoids, 1,8-cineole (43.4%), and α-terpinyl acetate (14.5%), and the monoterpene hydrocarbons, mostly sabinene (8.2%) and β-pinene (4.0%). Results clearly indicate that M. lucida essential oil can be used as an effective alternative for pulse beetle C. maculatus control, and it could be tested against other pulse beetles affecting Asia and Africa and throughout the world, thereby reducing use of synthetic pesticides. PMID:25143991

  6. Sex-specific molecular genetic response to UVB exposure in Xiphophorus maculatus skin.

    PubMed

    Boswell, William; Boswell, Mikki; Titus, James; Savage, Markita; Lu, Yuan; Shen, Jianjun; Walter, Ronald B

    2015-12-01

    In both Xiphophorus fishes and humans, males are reported to have a higher incidence of melanoma than females. To better understand sex-specific differences in the molecular genetic response to UVB, we performed RNA-Seq experiments in skin of female and male Xiphophorus maculatus Jp 163 B following UVB doses of 8 or 16kJ/m(2) exposure. Male X. maculatus differentially express a significantly larger number of transcripts following exposure to 16kJ/m(2) UVB (1293 genes) compared to 8kJ/m(2) UVB (324 genes). Female skin showed differential gene expression in a larger number of transcripts following 8kJ/m(2) UVB (765) than did males; however, both females and males showed similar numbers of differentially expressed genes at 16kJ/m(2) UVB (1167 and1293, respectively). Although most modulated transcripts after UVB exposure represented the same dominant pathways in both females and males (e.g., DNA repair, circadian rhythm, and fatty acid biosynthesis), we identified genes in several pathways that exhibited opposite modulation in female vs. male skin (e.g., synaptic development, cell differentiation, wound healing, and glucose metabolism). The oppositely modulated genes appear related through uncoupling protein 3 (UCP3) that is involved with the regulation of fatty acid oxidation and serves to balance glucose and lipid metabolism. Overall, these results identify gender-specific differences in UVB-induced genetic profiles in the skin of females and males and show female and male X. maculatus respond to UVB differently through pathways involved in reactive oxygen species, wound healing, and energy homeostasis. PMID:26256120

  7. Fine structure of a freshwater teleost (Pimelodus maculatus) hepatocytes revealed by ultrathin sections.

    PubMed

    Bonates, A B; Ferri, S

    1980-01-01

    The hepatocytes of Pimelodus maculatus studied in thin sections revealed: 1. 3 physiological surfaces: a) in content with the Disse's space; b) in contact with neighboring hepatocytes; and c) showing grooves that delimit bile canaliculi; 2. bile canaliculi presenting, sometimes, intracellular diverticula; 3. junctional complexes joining hepatocytes close to the bile canaliculi; 4. gap junctions in great number; 5. a characteristic feature of the RER; 6. a commonly close relationship between mitochondria and RER; 7. Golgi complexes near the bile canaliculi and in the perinuclear area; 8. smooth endoplasmic reticulum, lysosomes, glycogen and lipids in small amounts. PMID:7212288

  8. Isolation and characterization of microsatellite loci in Pimelodus maculatus (Siluriformes: Pimelodidae).

    PubMed

    Paiva, Ana Luiza B; Kalapothakis, Evanguedes

    2008-09-01

    To evaluate genetic variability in Pimelodus maculatus, a small migratory catfish common in South America, we isolated and characterized several microsatellite markers from individuals collected from a population in the River Grande (Brazil). A total of 11 loci were obtained and analyzed. All the loci were polymorphic, with the number of alleles ranging from three to 27 per locus. Observed and expected heterozygosities ranged from 0.5 to 0.89 and from 0.53 to 0.95, respectively. These polymorphic markers can be used as effective tools to study the genetic structure in populations of this species. PMID:21585977

  9. Analyses of nucleolus organizer regions and heterochromatin of Pimelodus maculatus (Pisces, Pimelodidae).

    PubMed

    Swarça, A C; Giuliano-Caetano, L; Dias, A L

    2000-01-01

    Eighteen specimens of Pimelodus maculatus collected from Tibagi River (Sertaneja, PR, Brazil) were analyzed cytogenetically. The diploid number of 56 chromosomes was observed and karyotype was 20 M + 20 SM + 10 ST + 6 A with fundamental number (FN) of 106. Results of analyses from the nucleolus organizer regions (NORs), obtained by AgNO3, CMA3 and C-band staining showed marking in a terminal position on the long arm of a pair of subtelocentric chromosomes. The restriction enzyme AluI produced a linear differentiation similar to C-banding. PMID:11519880

  10. Comparative effects of Cymbopogon schoenanthus essential oil and piperitone on Callosobruchus maculatus development.

    PubMed

    Ketoh, Guillaume K; Koumaglo, Honore K; Glitho, Isabelle A; Huignard, Jacques

    2006-12-01

    The insecticidal activity of crude essential oil extracted from Cymbopogon schoenanthus and of its main constituent, piperitone, was assessed on different developmental stages of Callosobruchus maculatus. Piperitone was more toxic to adults with a LC(50) value of 1.6 microl/l vs. 2.7 microl/l obtained with the crude extract. Piperitone inhibited the development of newly laid eggs and of neonate larvae, but was less toxic than the crude extract to individuals developing inside the seeds. PMID:16938411

  11. Estudio de la transparencia de las nubes de Magallanes a partir de la observación espectroscópica de galaxias ubicadas en dirección a las mismas

    NASA Astrophysics Data System (ADS)

    Dutra, C.; Bica, E.; Clariá, J. J.; Piatti, A. E.:

    Se presentan los primeros resultados obtenidos a partir de observaciones espectroscópicas de galaxias ubicadas en dirección a las Nubes de Magallanes. Los espectros fueron obtenidos con el telescopio de 2.15 m del CASLEO y cubren el rango 3500-7000 Å. El material observacional recolectado permite examinar poblaciones estelares y determinar el enrojecimiento interestelar que afecta a cada una de las galaxias. La distribución angular de la muestra de galaxias observadas permite efectuar el mapeamiento del enrojecimiento que afecta las distintas regiones de las Nubes de Magallanes.

  12. Effect of diet and refugia on development of Dermestes maculatus DeGeer reared in a laboratory

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The hide beetle (Dermestes maculatus DeGeer) is a Dermestid beetle that can infest a wide variety of stored products, including pet foods and animal feeds, dried foods, and grains products with high protein content. Although there is published information concerning the biology and habits of D. macu...

  13. Lethal and Sublethal Effects of Essential Oils from Eucalyptus camaldulensis and Heracleum persicum Against the Adults of Callosobruchus Maculatus

    PubMed Central

    Izakmehri, Khadijeh; Saber, Moosa; Mehrvar, Ali; Hassanpouraghdam, Mohammad Bagher; Vojoudi, Samad

    2013-01-01

    The cowpea weevil, Callosobruchus maculatus F. (Coleoptera: Bruchidae), is an important pest of stored cowpea, Vigna ungiculata (L.) Walpers (Fabales: Fabaceae), with ample distribution in tropical and subtropical regions. Many plant essential oils have a broad-spectrum activity against pest insects, and these oils traditionally have been used in the protection of stored products. In this study, the lethal and sublethal effects of essential oils from Eucalyptus camaldulensis Dehnh. (Myrtales: Myrtaceae) and Heracleum persicum Desf. (Apiales: Apiaceae) were evaluated on the adults of C. maculatus at 26 ± 1° C, 70 ± 5% RH, and a photoperiod of 16:8 L:D. The LC50 values of E. camaldulensis and H. persicum were 56.7 and 219.4 µL/L air after 12 hr and 26.1 and 136.4 µL/L air after 24 hr of exposure, respectively. The LT50 values of E. camaldulensis and H.persicum were 6.3 and 10.9 hr, respectively. The results showed that low lethal concentration (LC20) of essential oils negatively affected the longevity, fecundity, and fertility of female adults. The sex ratio of C. maculatus offspring was not significantly affected by essential oils. Therefore, these essential oils can be suggested for controlling C. maculatus in storage systems. The introduction of essential oils into storage systems could potentially decrease seed losses. PMID:24773362

  14. Isolation and characterization of an anti-insect β-toxin from the venom of the scorpion Isometrus maculatus.

    PubMed

    Kawachi, Tomoyuki; Miyashita, Masahiro; Nakagawa, Yoshiaki; Miyagawa, Hisashi

    2013-01-01

    Im-3 was isolated from the venom of the scorpion Isometrus maculatus through several steps of HPLC fractionation based on the insect paralytic activity. Injecting Im-3 into crickets induced paralysis, but no toxicity was apparent in mice after an intracerebroventricular injection. Im-3 shares sequence similarity to scorpion β-toxins that specifically affect insect sodium channels. PMID:23291760

  15. Sex allocation and interactions between relatives in the bean beetle, Callosobruchus maculatus.

    PubMed

    Reece, Sarah E; Wherry, Ruth N; Bloor, Juliette M G

    2005-11-01

    When a small number of females contribute offspring to a discrete mating group, sex allocation (Local Mate Competition: LMC) theory predicts that females should bias their offspring sex ratio towards daughters, which avoids the fitness costs of their sons competing with each other. Conversely, when a large number of females contribute offspring to a patch, they are expected to invest equally in sons and daughters. Furthermore, sex ratios of species that regularly experience variable foundress numbers are closer to those predicted by LMC theory than species that encounter less variable foundress number scenarios. Due to their patterns of resource use, female Callosobruchus maculatus are likely to experience a broad range of foundress number scenarios. We carried out three experiments to test whether female C. maculatus adjust their sex ratios in response to foundress number and two other indicators of LMC: ovipositing on pre-parasitised patches and ovipositing with sisters. We did not find any evidence of the predicted sex ratio adjustment, but we did find evidence of kin biased behaviour. PMID:16150553

  16. New morphological data on Cucullanus pinnai pinnai (Nematoda) parasitizing Pimelodus maculatus (Pimelodidae) in southeastern Brazil.

    PubMed

    Vieira, Vivian Suane de Freitas; Vieira, Fabiano Matos; Luque, José Luis

    2015-01-01

    This paper describes the morphology of Cucullanus pinnai pinnai parasitizing Pimelodus maculatus in the Guandu River, Brazil, based on differential interference contrast (DIC) microscopy and scanning electron microscopy (SEM), providing new morphological data about this species of parasite. Nematodes were collected between May and October 2012 from specimens of Pimelodus maculatus in the Guandu River (22°48'2"S, 43°37'35"W), in the state of Rio de Janeiro, Brazil. Some characteristics of specimens of Cucullanus in this study fall within the range of morphological variations of previously studied C. pinnai pinnai. Most of the specimens studied here had excretory pore and deirids located at the posterior end of the oesophagus, a feature not recorded in previous studies of this species. In addition, the size of the gubernaculum was larger than the other specimens previously studied. The SEM and DIC analyses of C. pinnai revealed several morphological details of the cephalic region and the tail papillae. With regard to the polymorphism of C. pinnai, morphological and genetic studies of this cucullanid nematode are needed, involving large numbers of host species and a wide geographical distribution. PMID:26154955

  17. Presence of the storage seed protein vicilin in internal organs of larval Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Uchôa, Adriana F; DaMatta, Renato A; Retamal, Claudio A; Albuquerque-Cunha, José M; Souza, Sheila M; Samuels, Richard I; Silva, Carlos P; Xavier-Filho, José

    2006-02-01

    Variant vicilins (7S storage globulins) of cowpea seeds (Vigna unguiculata) are considered as the main resistance factor present in some African genotypes against the bruchid Callosobruchus maculatus. It has been suggested that the toxic properties of vicilins may be related to their recognition and interaction with glycoproteins and other membrane constituents along the digestive tract of the insect. However, the possibility of a systemic effect has not yet been investigated. The objective of this work was to study the fate of 7S storage globulins of V. unguiculata in several organs of larvae of the cowpea weevil C. maculatus. Results demonstrated binding of vicilins to brush border membrane vesicles, suggesting the existence of specific receptors. Vicilins were detected in the haemolymph, in the midgut, and in internal organs, such as fat body and malpighian tubules. There is evidence of accumulation of vicilins in the fat body of both larvae and adults. The absorption of vicilins and their presence in insect tissues parallels classical sequestration of secondary compounds. PMID:16288905

  18. Intron-loss evolution of hatching enzyme genes in Teleostei

    PubMed Central

    2010-01-01

    Background Hatching enzyme, belonging to the astacin metallo-protease family, digests egg envelope at embryo hatching. Orthologous genes of the enzyme are found in all vertebrate genomes. Recently, we found that exon-intron structures of the genes were conserved among tetrapods, while the genes of teleosts frequently lost their introns. Occurrence of such intron losses in teleostean hatching enzyme genes is an uncommon evolutionary event, as most eukaryotic genes are generally known to be interrupted by introns and the intron insertion sites are conserved from species to species. Here, we report on extensive studies of the exon-intron structures of teleostean hatching enzyme genes for insight into how and why introns were lost during evolution. Results We investigated the evolutionary pathway of intron-losses in hatching enzyme genes of 27 species of Teleostei. Hatching enzyme genes of basal teleosts are of only one type, which conserves the 9-exon-8-intron structure of an assumed ancestor. On the other hand, otocephalans and euteleosts possess two types of hatching enzyme genes, suggesting a gene duplication event in the common ancestor of otocephalans and euteleosts. The duplicated genes were classified into two clades, clades I and II, based on phylogenetic analysis. In otocephalans and euteleosts, clade I genes developed a phylogeny-specific structure, such as an 8-exon-7-intron, 5-exon-4-intron, 4-exon-3-intron or intron-less structure. In contrast to the clade I genes, the structures of clade II genes were relatively stable in their configuration, and were similar to that of the ancestral genes. Expression analyses revealed that hatching enzyme genes were high-expression genes, when compared to that of housekeeping genes. When expression levels were compared between clade I and II genes, clade I genes tends to be expressed more highly than clade II genes. Conclusions Hatching enzyme genes evolved to lose their introns, and the intron-loss events occurred at the specific points of teleostean phylogeny. We propose that the high-expression hatching enzyme genes frequently lost their introns during the evolution of teleosts, while the low-expression genes maintained the exon-intron structure of the ancestral gene. PMID:20796321

  19. Control of Cowpea Weevil, Callosobruchus Maculatus (F.) (Coleoptera: Bruchidae), Using Natural Plant Products

    PubMed Central

    Tiroesele, Bamphitlhi; Thomas, Kesegofetse; Seketeme, Seipati

    2014-01-01

    A laboratory study was conducted to investigate the effects of natural products on the reproduction and damage of Callosobruchus maculatus, the cowpea weevil, on cowpea seeds at Botswana College of Agriculture in Gaborone, Botswana. The cowpea variety Blackeye was used in the study. Fifty grams of each plant product (garlic, peppermint and chilies) was added to 500 g of the cowpea seeds. Findings of this experiment revealed that chilies and garlic had negative effects on cowpea weevils for all parameters measured. Peppermint also showed significant reduction in the F1 progeny of the cowpea weevils but with less effect on weevils than garlic and chilies. The results indicate that these plant products have the potential to protect cowpea seeds from cowpea weevils’ damage compared to when the seeds are left or stored unprotected. They should, therefore, be included in pest management strategies for cowpea weevil in grains stored on-farm in rural tropical and subtropical regions. PMID:26463066

  20. Genetic characterization of the Neotropical catfish Pimelodus maculatus (Pimelodidae, Siluriformes) in the Upper Uruguay River.

    PubMed

    Ribolli, Josiane; de Melo, Cláudio Manoel Rodrigues; Zaniboni-Filho, Evoy

    2012-12-01

    Freshwater fish present unique challenges when one attempts to understand the factors that determine the structure of their populations. Habitat fragmentation is a leading cause of population decline that threatens ecosystems worldwide. In this study, we investigated the conservation status of genetic variability in the Neotropical catfish (Pimelodus maculatus). Specifically, we examined the structure and genetic diversity of this species in a region of the Upper Uruguay River fragmented by natural barriers and dams. There was no genetic structure among the four sites analyzed, indicating the existence of only one population group. A combination of environmental management and genetic monitoring should be used to minimize the impact of impoundment on panmitic populations of migratory fish species. PMID:23271936

  1. Swimming performance of the freshwater neotropical fish: Pimelodus maculatus Lacepède, 1803.

    PubMed

    Santos, H A; Pompeu, P S; Vicentini, G S; Martinez, C B

    2008-05-01

    The present study used fixed and increasing velocity tests in an experimental apparatus based on Brett's respirometer to examine prolonged and sustained speeds of the "mandi-amarelo", Pimelodus maculatus. When comparing the curves of critical speed versus total length between the mandi and the sockeye salmon Oncorhynchus nerka, it is observed that for an equal total length, the mandi presents a greater speed, probably due to water temperature differences. The sustained speed for the species was estimated in 5 lengths per second and the percentage of fatigued fish within time in a certain velocity was established. The data raised for the mandi represents an important contribution to the improvement of the handling of the species, providing guidance and criteria for designing several structures, such as fishways, fish screens and guidance systems. PMID:18660976

  2. Myxobolus absonus sp. n. (Myxozoa: Myxosporea) parasitizing pimelodus maculatus (siluriformes: Pimelodidae), a South American freshwater fish.

    PubMed

    Cellere, Eduardo F; Cordeiro, Nelson S; Adriano, Edson A

    2002-01-01

    A new myxoporean species is described from a freshwater fish in Brazil. Myxobolus absonus sp. n. was found infecting Pimelodus maculatus captured in the river Piracicaba, State of São Paulo, Brazil. Cysts were found free in the opercular cavity. The spores are large (length--15.7 +/- 1.5 microns, width--10.2 +/- 0.7 microns; mean +/- S.D.) and oval in shape, with the anterior end slightly pointed. The spore valves are relatively thin, smooth, and asymmetrical in a frontal view. The polar capsules are pyriform in shape, and unequal in size; the largest are 6.4 +/- 0.7 microns long and 3.6 +/- 0.5 microns wide, while the smallest are 4.2 +/- 0.6 microns long and 2.5 +/- 0.5 microns wide. PMID:11992152

  3. Larval Competition Reduces Body Condition in the Female Seed Beetle, Callosobruchus maculatus

    PubMed Central

    Schade, Daynika J.; Vamosi, Steven M.

    2012-01-01

    Early body condition may be important for adult behavior and fitness, and is impacted by a number of environmental conditions and biotic interactions. Reduced fecundity of adult females exposed to larval competition may be caused by reduced body condition or shifts in relative body composition, yet these mechanisms have not been well researched. Here, body mass, body size, scaled body mass index, and two body components (water content and lean dry mass) of adult Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae: Bruchinae) females exposed to larval competition or reared alone were examined. Experimental females emerged at significantly smaller body mass and body size than control females. Additionally, scaled body mass index and water content, but not lean dry mass, were significantly reduced in experimental females. To our knowledge, these are the first results that demonstrate a potential mechanism for previously documented direct effects of competition on fecundity in female bruchine beetles. PMID:22954282

  4. Genetic characterization of the Neotropical catfish Pimelodus maculatus (Pimelodidae, Siluriformes) in the Upper Uruguay River

    PubMed Central

    Ribolli, Josiane; de Melo, Cláudio Manoel Rodrigues; Zaniboni-Filho, Evoy

    2012-01-01

    Freshwater fish present unique challenges when one attempts to understand the factors that determine the structure of their populations. Habitat fragmentation is a leading cause of population decline that threatens ecosystems worldwide. In this study, we investigated the conservation status of genetic variability in the Neotropical catfish (Pimelodus maculatus). Specifically, we examined the structure and genetic diversity of this species in a region of the Upper Uruguay River fragmented by natural barriers and dams. There was no genetic structure among the four sites analyzed, indicating the existence of only one population group. A combination of environmental management and genetic monitoring should be used to minimize the impact of impoundment on panmitic populations of migratory fish species. PMID:23271936

  5. Intra-specific variation in female remating in Callosobruchus chinensis and C. maculatus.

    PubMed

    Miyatake, Takahisa; Matsumura, Fumi

    2004-05-01

    The effects of mating duration on female remating (exp. 1) and under different male densities (exp. 2) were examined in two strains of the adzuki bean beetle, Callosobruchus chinensis and in one strain of the bruchid beetle, C. maculatus. In experiment 1, the frequency of female remating was markedly different between the two strains of C. chinensis. Females of the jC strain, reared long-term in the laboratory, did not remate after being allowed to mate freely (=monogamy), whereas females of the isC strain, recently established from the field, showed high remating frequencies (=polyandry). In both strains, the frequency of female remating increased after the duration of the first mating was deliberately shortened. The relation between mating duration and remating frequency was significantly different, however, between the two strains. In a closely related species, C. maculatus, which manifests polyandry, this relation was more similar to that of the field-derived (=isC) than to that of the laboratory-derived (=jC) strain of C. chinensis. The reasons for the inter-strain variation observed in the remating frequencies of C. chinensis are also discussed. In experiment 2, the mating duration of the three strains was compared under different male densities. Only the lab-derived strain demonstrated a significantly shorter mating duration when one female was placed together with five males than when paired with one male. The shorter mating duration (approximately 26 s) was similar to that of females allowed to remate in the monogamous strain in experiment 1. PMID:15121453

  6. Molecular genetic response of Xiphophorus maculatus-X. couchianus interspecies hybrid skin to UVB exposure.

    PubMed

    Lu, Yuan; Bowswell, Mikki; Bowswell, William; Yang, Kuan; Schartl, Manfred; Walter, Ronald B

    2015-12-01

    The phenotypic and genetic similarities between Xiphophorus and human melanoma render Xiphophorus a useful animal model for studying the genetic basis of melanoma etiology. In the Xiphophorus model, melanoma has been shown to be inducible by ultraviolet light (UVB) exposure among interspecies hybrids, but not in parental line fish similarly treated. This leads to questions of what genes are responsive to UVB exposure in the skin of the interspecies hybrids, as well as how parental alleles in hybrids may be differentially regulated and the potential roles they may play in induced melanomagenesis. To address these questions, we produced X. maculatus Jp 163 B×X. couchianus (Sp-Couch) F1 hybrid fish, exposed both hybrid and parental fish to UVB, and performed gene expression profiling of the skin using RNA-Seq methodology. We characterized a group of unique UVB-responsive genes in Sp-Couch hybrid including dct, pmela, tyr, tyrp1a, slc2a11b, rab38a, rab27, tspan10, slc45a2, oca2, slc24a5, ptn and mitfa. These genes are associated with melanin production and melanocyte proliferation. They were also up-regulated in Sp-Couch hybrid, indicating that their UVB response is hybridization initiated. In the hybrid, several melanin production and pigmentation related genes, including slc45a2, tspan10, dct, slc2a11b and ptn showed either X. couchianus or X. maculatus allele specific expression. The finding that these genes exhibit allele specific expression regulatory mechanisms in Sp-Couch hybrids, but do not exhibit a corresponding UVB response in either one of the parental fishes, may suggest UVB targets and imply mechanisms regarding the susceptibility of Sp-Couch to induced melanomagenesis. PMID:26254713

  7. Complete mitochondrial genome of the endemic species Korean aucha perch Coreoperca herzi (Teleostei, Centrarchiformes, Sinipercidae).

    PubMed

    Park, Chang Eon; Park, Gun-Seok; Kwak, Yunyoung; Hong, Sung-Jun; Khan, Abdur Rahim; Jung, Byung Kwon; Park, Yeong-Jun; Kim, Min-Chul; Kim, Kgu-Hwan; Park, Hee Cheon; Lee, In-Jung; Shin, Jae-Ho

    2016-09-01

    In this study, we sequenced the complete mitochondrial genome of the endemic species Korean aucha perch Coreoperca herzi (Teleostei, Centrarchiformes, Sinipercidae). The mitogenome, consisting of 16 495 base pairs (bp), encoded 13 protein-coding genes (PCGs), 2 ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs) and 2 non-coding region. The overall base composition of C. herzi is G + C: 46.3%, A + T: 53.7%, apparently with a slight AT bias. Phylogenetic analysis showed that the C. herzi was closed to Coreoperca kawamebari. PMID:26181210

  8. Complete mitochondrial genome of the Korean endemic species Microphysogobio yaluensis (Teleostei, Cypriniformes, Cyprinidae).

    PubMed

    Park, Chang Eon; Park, Gun-Seok; Kim, Min-Chul; Kim, Kgu-Hwan; Park, Hee Cheon; Lee, In-Jung; Shin, Jae-Ho

    2016-09-01

    In this study, we sequenced the complete mitochondrial genome of the Korean endemic species Microphysogobio yaluensis (Teleostei, Cypriniformes, Cyprinidae). The mitogenome, consisted of 16 601 base pairs (bp), encoding 13 protein-coding genes (PCGs), 2 ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs) and 2 non-coding regions. The overall base composition of M. yaluensis was G + C: 43.8%, A + T: 56.2%, apparently with a slight AT bias. Phylogenetic analysis showed that M. yaluensis was close to Hemibarbus mylodon. PMID:26260172

  9. The complete mitochondrial genome sequence of Squalidus japonicus coreanus (Teleostei, Cypriniformes, Cyprinidae).

    PubMed

    Eon Park, Chang; Park, Gun-Seok; Kwak, Yunyoung; Kim, Min-Chul; Kim, Kgu-Hwan; Park, Hee Cheon; Shin, Jae-Ho

    2016-09-01

    The short-barbel gudgeon Squalidus japonicus coreanus (Teleostei, Cypriniformes, Cyprinidae) is a subspecies of S. japonicus, and is endemic to Korea. The complete mitochondrial genome sequence consisted of 16 597 base pairs (bp) encoding 13 protein-coding genes (PCGs), two ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs), and two non-coding regions. The overall base composition of S. japonicus coreanus was G + C: 47.4% and A + T: 52.6%, apparently with a slight AT bias. Phylogenetic analysis showed that S. japonicus coreanus was closely related to Pungtungia herzi. PMID:26329666

  10. Efficacy of nanostructured silica as a stored pulse protector against the infestation of bruchid beetle, Callosobruchus maculatus (Coleoptera: Bruchidae)

    NASA Astrophysics Data System (ADS)

    Arumugam, Ganesh; Velayutham, Veeramani; Shanmugavel, Sakthivelkumar; Sundaram, Janarthanan

    2015-04-01

    The treatment of hydrophobic silica nanoparticles (SNPs) with the pulse seeds of Cajanus cajan, Macrotyloma uniflorum, Vigna mungo, Vigna radiata, Cicer arietinum and Vigna unguiculata against the infestation of stored pulse beetle, Callosobruchus maculatus revealed a significant reduction in oviposition, adult emergence and seed damage potential. There was a complete retardation of growth of this beetle in the treated seeds of C. cajan. SNP-treated seeds of these six varieties of pulses revealed no effect on the growth of seeds as revealed by seed germination, growth rate of root and shoot. Similarly, the soil microflora measured in terms of colony forming units was not affected by silica nanoparticles upon its treatment with pulse seeds. The results of this study thus clearly demonstrated the useful nature of silica nanoparticles as seed protecting agent for the control of C. maculatus.

  11. Efficacy of nanostructured silica as a stored pulse protector against the infestation of bruchid beetle, Callosobruchus maculatus (Coleoptera: Bruchidae)

    NASA Astrophysics Data System (ADS)

    Arumugam, Ganesh; Velayutham, Veeramani; Shanmugavel, Sakthivelkumar; Sundaram, Janarthanan

    2016-03-01

    The treatment of hydrophobic silica nanoparticles (SNPs) with the pulse seeds of Cajanus cajan, Macrotyloma uniflorum, Vigna mungo, Vigna radiata, Cicer arietinum and Vigna unguiculata against the infestation of stored pulse beetle, Callosobruchus maculatus revealed a significant reduction in oviposition, adult emergence and seed damage potential. There was a complete retardation of growth of this beetle in the treated seeds of C. cajan. SNP-treated seeds of these six varieties of pulses revealed no effect on the growth of seeds as revealed by seed germination, growth rate of root and shoot. Similarly, the soil microflora measured in terms of colony forming units was not affected by silica nanoparticles upon its treatment with pulse seeds. The results of this study thus clearly demonstrated the useful nature of silica nanoparticles as seed protecting agent for the control of C. maculatus.

  12. The seed coat of Phaseolus vulgaris interferes with the development of the cowpea weevil [Callosobruchus maculatus (F.) (Coleoptera: Bruchidae)].

    PubMed

    Silva, Luciana B; Sales, Maurício P; Oliveira, Antônia E A; Machado, Olga L T; Fernandes, Kátia V S; Xavier-Filho, José

    2004-03-01

    We have confirmed here that the seeds of the common bean (Phaseolus vulgaris, L.) do not support development of the bruchid Callosobruchus maculatus (F.), a pest of cowpea [Vigna unguiculata (L.) Walp] seeds. Analysis of the testa (seed coat) of the bean suggested that neither thickness nor the levels of compounds such as tannic acid, tannins, or HCN are important for the resistance. On the other hand, we have found that phaseolin (vicilin-like 7S storage globulin), detected in the testa by Western blotting and N-terminal amino acid sequencing, is detrimental to the development of C. maculatus. As for the case of other previously studied legume seeds (Canavalia ensiformis and Phaseolus lunatus) we suggest that the presence of vicilin-like proteins in the testa of P. vulgaris may have had a significant role in the evolutionary adaptation of bruchids to the seeds of leguminous plants. PMID:15048195

  13. Complete mitochondrial genomes for Icelus spatula, Aspidophoroides olrikii and Leptoclinus maculatus: pan-Arctic marine fishes from Canadian waters.

    PubMed

    Swanburg, Taylor; Horne, John B; Baillie, Shauna; King, Stanley D; McBride, Meghan C; Mackley, Michael P; Paterson, Ian G; Bradbury, Ian R; Bentzen, Paul

    2016-07-01

    Three Arctic marine fishes Icelus spatula, Aspidophoroides olrikii and Leptoclinus maculatus have been identified as target species for investigating the effects of ocean warming on population patterns in high-latitude marine habitats around Canada. In preparation for this research, we have resolved whole mitochondrial genome sequences of 16 384, 17 200 and 16 384 bp for each species, respectively. GC content for each species was 47.5%, 44.2% and 45.3%, respectively. Mitogenome gene composition included 13 protein-encoding genes, 2 rRNA and 22 tRNA genes, for I. spatula and L. maculatus, consistent with other teleosts. Only 20 tRNA genes were annotated for A. olrikii, because tRNA-Pro and tRNA-Thr are poorly characterized and aberrantly located in this species. PMID:26122337

  14. The structure of the monogenean community on the gills of Pimelodus maculatus in Río de la Plata (Argentina).

    PubMed

    Gutiérrez, P A; Martorelli, S R

    1999-08-01

    The Monogenea fauna was studied from the gills of the catfish Pimelodus maculatus. Fish were caught from Río de la Plata, in Buenos Aires harbour (Argentina). Five species of Monogenea were found. The structure of the monogenean community was analysed at the component and infracommunity level. The nature of the monogenean community, its possible interactivity, seasonal variation and predictability are also discussed. PMID:10466125

  15. Ultrastructure of the epidermal cells of the teleost Pimelodus maculatus Lacépède, 1803 (pisces).

    PubMed

    Ferri, S; Stipp, A C; Sesso, A; Correa, H

    1977-01-01

    By means of electronmicroscope technique were studied the cell types in the epidermis of the teleost Pimelodus maculatus LACEPEDE. The varied cells were described after their morphological aspect. The behaviour of the plasma membrane and the cytoplasmatic components, especially the microfilaments and the rough endoplasmatic reticulum, were discussed in the functionally manner of this cells. The relationship of the cell types to the mitotic cell cycle gave some interesting references. PMID:900513

  16. Susceptibility of the bruchid Callosobruchus maculatus (Coleoptera: Bruchidae) and its parasitoid Dinarmus basalis (Hymenoptera: Pteromalidae) to three essential oils.

    PubMed

    Ketoh, Guillaume K; Glitho, Adole I; Huignard, Jacques

    2002-02-01

    The bruchid Callosobruchus maculatus (F.) causes major losses during the storage of seeds of Vigna unguiculata (Walp.) in West Africa. An endemic parasitoid, the pteromalid Dinarmus basalis (Rond.) reduces the increase in bruchid populations in stores and could be used for biological control. African farmers often introduce essential oils into granaries at harvest time. In Togo, essential oils were extracted from two Gramineae, Cymbopogon nardus (L.) and Cymbopogon schoenanthus (L.) and from a Lamiaceae, Ocimum basilicum (L.). The major components of these essential oils were citronellal in C. nardus, carene-2 and piperitone in C. schoenanthus and estragol in O. basilicum. Cymbopogon schoenanthus was the most toxic oil for C. maculatus adults. D. basalis adults were more susceptible to the three essential oils than the adults of their hosts C. maculatus. In the presence of cowpea seeds, the LC50s of the three essential oils were lower than in their absence, suggesting that the seeds may absorb a part of the volatiles. High doses of three essential oils slightly affected the survival of the fourth instar or the pupae of C. maculatus. This high survival was due to protection of larvae from volatiles by the surrounding seeds. The D. basalis were more affected by the oil volatiles than their hosts. Sub-lethal doses of essential oils reduced the duration of the adult life of both insect species and fecundity of the females. The differences in sensitivity of the host and its parasitoid could influence their population dynamics. The introduction of the essential oils into storage systems potentially could reduce density of parasitoid populations and increase seed losses. PMID:11942754

  17. Morphological and molecular data reveal a new species of Neoechinorhynchus (Acanthocephala: Neoechinorhynchidae) from Dormitator maculatus in the Gulf of Mexico.

    PubMed

    Pinacho-Pinacho, Carlos Daniel; Sereno-Uribe, Ana L; García-Varela, Martín

    2014-12-01

    Neoechinorhynchus (Neoechinorhynchus) mexicoensis sp. n. is described from the intestine of Dormitator maculatus (Bloch 1792) collected in 5 coastal localities from the Gulf of Mexico. The new species is mainly distinguished from the other 33 described species of Neoechinorhynchus from the Americas associated with freshwater, marine and brackish fishes by having smaller middle and posterior hooks and possessing a small proboscis with three rows of six hooks each, apical hooks longer than other hooks and extending to the same level as the posterior hooks, 1 giant nucleus in the ventral body wall and females with eggs longer than other congeneric species. Sequences of the internal transcribed spacer (ITS) and the large subunit (LSU) of ribosomal DNA including the domain D2+D3 were used independently to corroborate the morphological distinction among the new species and other congeneric species associated with freshwater and brackish water fish from Mexico. The genetic divergence estimated among congeneric species ranged from 7.34 to 44% for ITS and from 1.65 to 32.9% for LSU. Maximum likelihood and Bayesian inference analyses with each dataset showed that the 25 specimens analyzed from 5 localities of the coast of the Gulf of Mexico parasitizing D. maculatus represent an independent clade with strong bootstrap support and posterior probabilities. The morphological evidence, plus the monophyly in the phylogenetic analyses, indicates that the acanthocephalans collected from intestine of D. maculatus from the Gulf of Mexico represent a new species, herein named N. (N.) mexicoensis sp. n. PMID:25064596

  18. Habitat characterization and mapping of Anopheles maculatus (Theobald) mosquito larvae in malaria endemic areas in Kuala Lipis, Pahang, Malaysia.

    PubMed

    Rohani, A; Wan Najdah, W M A; Zamree, I; Azahari, A H; Mohd Noor, I; Rahimi, H; Lee, H L

    2010-07-01

    In Peninsular Malaysia, a large proportion of malaria cases occur in the central mountainous and forested parts of the country. As part of a study to assess remote sensing data as a tool for vector mapping, we conducted entomological surveys to determine the type of mosquitoes, their characteristics and the abundance of habitats of the vector Anopheles maculatus in malaria endemic areas in Pos Senderot. An. maculatus mosquitoes were collected from 49 breeding sites in Pos Senderot. An. maculatus preferred to breed in water pockets formed on the bank of rivers and waterfalls. The most common larval habitats were shallow pools 5.0-15.0 cm deep with clear water, mud substrate and plants or floatage. The mosquito also preferred open or partially shaded habitats. Breeding habitats were generally located at 100-400 m from the nearest human settlement. Changes in breeding characteristics were also observed. Instead of breeding in slow flowing streams, most larvae bred in small water pockets along the river margin. PMID:21073056

  19. A Kunitz-type inhibitor of coleopteran proteases, isolated from Adenanthera pavonina L. seeds and its effect on Callosobruchus maculatus.

    PubMed

    Macedo, Maria Lígia Rodrigues; de Sá, Claudia Mara; Freire, Maria Das Graças Machado; Parra, José Roberto Postali

    2004-05-01

    The cowpea weevil Callosobruchus maculatus is one of the major pests of Vigna unguiculata cowpea. Digestion in the cowpea weevil is facilitated by high levels of cysteine and aspartic acid proteinases. Plants synthesize a variety of molecules, including proteinaceous proteinase inhibitors, to defend themselves against attack by insects. In this work, a trypsin inhibitor (ApTI) isolated from Adenanthera pavonina seeds showed activity against papain. The inhibition of papain by ApTI was of the noncompetitive type, with a K(i) of 1 microM. ApTI was highly effective against digestive proteinases from C. maculatus, Acanthoscelides obtectus (bean weevil), and Zabrotes subfasciatus (Mexican bean weevil) and was moderately active against midgut proteinases from the boll weevil Anthonomus grandis and the mealworm Tenebrio molitor. In C. maculates fed an artificial diet containing 0.25% and 0.5% ApTI (w/w), the latter concentration caused 50% mortality and reduced larval weight gain by approximately 40%. The action of ApTI on C. maculatus larvae may involve the inhibition of ApTI-sensitive cysteine proteinases and binding to chitin components of the peritrophic membrane (or equivalent structures) in the weevil midgut. PMID:15113152

  20. Insecticidal action of Bauhinia monandra leaf lectin (BmoLL) against Anagasta kuehniella (Lepidoptera: Pyralidae), Zabrotes subfasciatus and Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Macedo, Maria Lígia Rodrigues; das Graças Machado Freire, Maria; da Silva, Maria Barbosa Reis; Coelho, Luana Cassandra Breitenbach Barroso

    2007-04-01

    Bruchid beetle larvae cause major losses in grain legume crops throughout the world. Some bruchid species, such as the cowpea weevil (Callosobruchus maculatus) and the Mexican bean weevil (Zabrotes subfasciatus), are pests that damage stored seeds. The Mediterranean flour moth (Anagasta kuehniella) is of major economic importance as a flour and grain feeder; it is often a severe pest in flour mills. Plant lectins have been implicated as antibiosis factors against insects. Bauhinia monandra leaf lectin (BmoLL) was tested for anti-insect activity against C. maculatus, Z. subfasciatus and A. kuehniella larvae. BmoLL produced ca. 50% mortality to Z. subfaciatus and C. maculatus when incorporated into an artificial diet at a level of 0.5% and 0.3% (w/w), respectively. BmoLL up to 1% did not significantly decrease the survival of A. kuehniella larvae, but produced a decrease of 40% in weight. Affinity chromatography showed that BmoLL bound to midgut proteins of the insect C. maculatus. 33 kDa subunit BmoLL was not digested by midgut preparations of these bruchids. BmoLL-fed C. maculatus larvae increased the digestion of potato starch by 25% compared with the control. The transformation of the genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops. PMID:16488638

  1. The importance of carcass volatiles as attractants for the hide beetle Dermestes maculatus (De Geer).

    PubMed

    von Hoermann, C; Ruther, J; Reibe, S; Madea, B; Ayasse, M

    2011-10-10

    A decaying cadaver emits volatile organic compounds that are used by necrophilous and necrophagous insects in order to find their brood substrate. Although volatile organic compounds (VOCs) that are released by carcasses have been identified, little is known about the specific compounds that are used by these insects while searching for a brood substrate. Therefore, we have investigated the chemical ecology involved in the attraction of the necrophagous hide beetle Dermestes maculatus, which feeds as an adult and larva upon decomposing carcasses. Our aims have been to identify the responsible compounds in the odours of the carcass that are important for the attraction of the beetles. Furthermore, we have studied sex- and age-related differences in beetle attraction and tested whether the hide beetle can distinguish between various stages of decomposition by means of the emitted odours. Headspace collection of volatiles released from piglet carcasses (bloated stage, post-bloating stage, advanced decay and dry remains), coupled gas chromatography-mass spectrometry (GC-MS), gas chromatography with electroantennographic detection (GC-EAD) and bioassays were conducted to identify the volatiles responsible for the attraction of the beetles. Freshly emerged male beetles were attracted by the odour of piglets in the post-bloating stage (9 days after death; T(mean) = 27 °C) and the EAD-active compound benzyl butyrate. Statistical analysis revealed a higher relative proportion of benzyl butyrate in the odour bouquet of the post-bloating stage in comparison with the other stages. We therefore conclude that this compound plays an important role in the attraction of hide beetles to carcass odour. This underlines the potential use of D. maculatus for the estimation of the post mortem interval. The decomposition stage at which the female beetles are attracted to the odour of a cadaver remains unknown, as does the nature of this attraction. Pheromones (sexual or aggregation pheromones) might play an essential role correlated with their attraction to carrion and consequently with their attraction to the substrate for mating and ovipositioning. PMID:21741784

  2. Transcriptome Analysis of Female and Male Xiphophorus maculatus Jp 163 A

    PubMed Central

    Zhang, Ziping; Wang, Yilei; Wang, Shuhong; Liu, Jingtao; Warren, Wesley; Mitreva, Makedonka; Walter, Ronald B.

    2011-01-01

    Background Xiphophorus models are important for melanoma, sex determination and differentiation, ovoviviparity and evolution. To gain a global view of the molecular mechanism(s) whereby gene expression may influence sexual dimorphism in Xiphophorus and to develop a database for future studies, we performed a large-scale transcriptome study. Methodology/Principal Findings The 454-FLX massively parallel DNA sequencing platform was employed to obtain 742,771 and 721,543 reads from 2 normalized cDNA libraries generated from whole adult female and male X. maculatus Jp 163 A, respectively. The reads assembled into 45,538 contigs (here, a "contig" is a set of contiguous sequences), of which, 11,918 shared homology to existing protein sequences. These numbers estimate that the contigs may cover 53% of the total number of Xiphophorus transcriptome. Putative translations were obtained for 11,918 cDNA contigs, of which, 3,049 amino acid sequences contain Pfam domains and 11,064 contigs encode secretory proteins. A total of 3,898 contigs were associated with 2,781 InterPro (IPR) entries and 5,411 contigs with 132 KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways. There were 10,446 contigs annotated with 69,778 gene ontology (GO) terms and the three corresponding organizing principles. Fifty-four potential sex differentially expressed genes have been identified from these contigs. Eight and nine of these contigs were confirmed by real-time PCR as female and male predominantly expressed genes respectively. Based on annotation results, 34 contigs were predicted to be differentially expressed in male and female and 17 of them were also confirmed by real-time PCR. Conclusions/Significance This is the first report of an annotated overview of the transcriptome of X. maculatus and identification of sex differentially expressed genes. These data will be of interest to researchers using the Xiphophorus model. This work also provides an archive for future studies in molecular mechanisms of sexual dimorphism and evolution, and can be used in comparative studies of other fish. PMID:21483681

  3. Galaxitaenia toloi n. gen., n. sp. (Eucestoda: Pseudophyllidea) from Galaxias platei (Pisces: Osmeriformes, Galaxiidae), in the Patagonian region of Argentina.

    PubMed

    Gil de Pertierra, Alicia A; Semenas, Liliana G

    2005-08-01

    Galaxitaenia n. gen. (Eucestoda: Pseudophyllidea) is proposed to accommodate Galaxitaenia toloi n. gen., n. sp. from Galaxias platei, a freshwater fish inhabiting Andean lakes in Argentine Patagonia. Galaxitaenia belongs to the Triaenophoridae because it possesses a marginal genital pore, a ventral uterine pore, and a follicular vitelline gland. The new genus can be distinguished from other triaenophorids by the following combination of characters: a scolex with a prominent rectangular apical disc without hooks, grooves, or indentations; neck present; segments wider than long to quadrangular; testes in 2 lateral fields, often connected anteriorly; cirrus unarmed; an ovary situated posteriorly; a vagina posterior to the cirrus sac; vitelline follicles medullary, in 2 ventral fields forming 2 wings interrupted medially; a uterus saccate to branched; and eggs without operculum. The types, distribution, and density of microtriches were analyzed on the surface of the tegument of scolex, neck, and immature segments. The presence of tumuli were observed on the apical disc of the scolex. Galaxitaenia toloi n. sp. is the first triaenophorid species recorded in a South American freshwater fish and the fourth helminth parasitizing the intestine of G. platei. PMID:17089762

  4. Lipid Status of the Two High Latitude Fish Species, Leptoclinus maculatus and Lumpenus fabricii

    PubMed Central

    Murzina, Svetlana A.; Nefedova, Zinaida A.; Falk-Petersen, Stig; Ripatti, Pauli O.; Ruokolainen, Tatiana R.; Pekkoeva, Svetlana N.; Nemova, Nina N.

    2013-01-01

    A comparative study of the lipid status (i.e., the total lipid and phospholipid concentrations and the percentage of fatty acids of the total lipids) of adult specimens of daubed shanny (Leptoclinus maculatus) from Svalbard waters (Isfjord) and slender eel blenny (Lumpenus fabricii) from the White Sea (Onega Bay and Tersky shore) was performed to study the metabolism and functions of lipids of these fishes in ontogeny and under various ecological conditions. Slender eel blenny from both areas of the White Sea were distinguished by a high level of sphingomyelin compared with the daubed shanny from Svalbard, and the amount of total phospholipids was higher in slender eel blenny from Onega Bay than in slender eel blenny from the Tersky shore. The extent of saturation and the signature of polyenic fatty acids varied according to the specific species of the Stichaeidae family under study. These results demonstrate the differences in the trophoecological and hydrobiological conditions of habitations of these species and highlighted the importance of considering certain trends in the lipid profiles of these fishes as specific features of the organization of the ecological and biochemical mechanisms of adaptation. PMID:23535338

  5. Molecular genetic response to varied wavelengths of light in Xiphophorus maculatus skin.

    PubMed

    Chang, Jordan; Lu, Yuan; Boswell, William T; Boswell, Mikki; Caballero, Kaela L; Walter, Ronald B

    2015-12-01

    Xiphophorus fishes represent a model often utilized to study UVB induced tumorigenesis. Recently, varied genetic responses to UVB exposure have been documented in the skin of female and male Xiphophorus, as have differences in UVB response in the skin of different parental species and for interspecies hybrids produced from crossing them. Additionally, it has been shown that exposure to "cool white" fluorescent light induces a shift in the genetic profiles of Xiphophorus skin that is nearly as robust as the UVB response, but involves a fundamentally different set of genes. Given these results and the use of Xiphophorus interspecies hybrids as an experimental model for UVB inducible melanoma, it is of interest to characterize genes that may be transcriptionally modulated in a wavelength specific manner. The global molecular genetic response of skin upon exposure of the intact animal to specific wavelengths of light has not been investigated. Herein, we report results of RNA-Seq experiments from the skin of male Xiphophorus maculatus Jp 163 B following exposure to varied 50nm wavelengths of light ranging from 300-600nm. We identify two specific wavelength regions, 350-400nm (88 genes) and 500-550nm (276 genes), that exhibit transcriptional modulation of a significantly greater number of transcripts than any of the other 50nm regions in the 300-600nm range. Observed functional sets of genes modulated within these two transcriptionally active light regions suggest different mechanisms of gene modulation. PMID:26460196

  6. Functional incompatibility between the fertilization systems of two allopatric populations of Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Brown, D V; Eady, P E

    2001-11-11

    Recent studies indicate that postcopulatory sexual selection may represent an important component of the speciation process by initiating reproductive isolation via the evolutionary divergence of fertilization systems. Using two geographically isolated populations of the polyandrous beetle Callosobruchus maculatus, we investigated divergence in fertilization systems by determining the extent of postcopulatory functional incompatibility. Through reciprocal, cross-population matings we were able to separately estimate the effects of male and female population origin and their interaction on the extent of last-male sperm precedence, female receptivity to further copulation and female oviposition. Our results indicate partial incompatibility between the fertilization systems of the two populations at all three functional levels. Males derived from the same population as females outcompete rival, allopatric males with respect to sperm preemption, sperm protection, and ability to stimulate female oviposition. This pattern is reciprocated in both populations indicating that postcopulatory, prezygotic events represent important mechanisms by which between-population gene flow is reduced. We suggest the partial gametic isolation observed is a by-product of the coevolution of male and female fertilization systems by a process of cryptic female choice. Our results are consistent with a mechanism akin to conventional mate choice models although they do not allow us to reject antagonistic sexual coevolution as the mechanism of cryptic female choice. PMID:11794785

  7. Use of commercial freezers to control cowpea weevil, Callosobruchus maculatus (Coleoptera: Bruchidae), in organic garbanzo beans.

    PubMed

    Johnson, J A; Valero, K A

    2003-12-01

    One California processor of organic garbanzo beans (Cicer arietinum L.), unable to use chemical fumigants, relies on 30-d storage at -18 degrees C to disinfest product of the cowpea weevil, Callosobruchus maculatus (F). To determine whether the storage period may be shortened, the most cold-tolerant life stage of the cowpea weevil was identified. Laboratory studies showed that the egg stage was most tolerant to -18 degrees C and that adults were most susceptible. To examine the efficacy of cold storage disinfestation, bags of black-eyed peas, Vigna unguiculata (L.) Walp., infested with cowpea weevil eggs were buried within garbanzo bean bins placed in a commercial cold storage facility kept at approximately -18 degrees C and removed after 7, 14, and 21 d. Survival was highest in eggs located at the center of the bins and coincided with the slowest cooling rate. Although temperatures within the bins did not reach -18 degrees C until after 14-19 d, egg mortality was estimated to be >98% after just 7 d of exposure. Complete mortality of eggs occurred after 14 d of cold storage. A 2-wk treatment regimen may be sufficient for control of cowpea weevil in organic legumes. PMID:14977138

  8. Genetic architecture of population differences in oviposition behaviour of the seed beetle Callosobruchus maculatus.

    PubMed

    Fox, C W; Stillwell, R C; Amarillo-S, A R; Czesak, M E; Messina, F J

    2004-09-01

    Few studies have examined the genetic architecture of population differences in behaviour and its implications for population differentiation and adaptation. Even fewer have examined whether differences in genetic architecture depend on the environment in which organisms are reared or tested. We examined the genetic basis of differences in oviposition preference and egg dispersion between Asian (SI) and African (BF) populations of the seed beetle, Callosobruchus maculatus. We reared and tested females on each of two host legumes (cowpea and mung bean). The two populations differed in mean oviposition preference (BF females preferred cowpea seeds more strongly than did SI females) and egg dispersion (SI females distributed eggs more uniformly among seeds than did BF females). Observations of hybrid and backcross individuals indicated that only the population difference in oviposition preference could be explained by complete additivity, whereas substantial dominance and epistasis contributed to the differences in egg dispersion. Both rearing host and test host affected the relative magnitude of population differences in egg dispersion and the composite genetic effects. Our results thus demonstrate that the relative influence of epistasis and dominance on the behaviour of hybrids depends on the behaviour measured and that different aspects of insect oviposition are under different genetic control. In addition, the observed effect of rearing host and oviposition host on the relative importance of dominance and epistasis indicates that the genetic basis of population differences depends on the environment in which genes are expressed. PMID:15312086

  9. Can Preference for Oviposition Sites Initiate Reproductive Isolation in Callosobruchus maculatus?

    PubMed Central

    Rova, Emma; Björklund, Mats

    2011-01-01

    Theory has identified a variety of evolutionary processes that may lead to speciation. Our study includes selection experiments using different host plants and test key predictions concerning models of speciation based on host plant choice, such as the evolution of host use (preference and performance) and assortative mating. This study shows that after only ten generations of selection on different resources/hosts in allopatry, strains of the seed beetle Callosobruchus maculatus develop new resource preferences and show resource-dependent assortative mating when given the possibility to choose mates and resources during secondary contact. The resulting reduced gene flow between the different strains remained for two generations after contact before being overrun by disassortative mating. We show that reduced gene flow can evolve in a population due to a link between host preference and assortative mating, although this result was not found in all lines. However, consistent with models of speciation, assortative mating alone is not sufficient to maintain reproductive isolation when individuals disperse freely between hosts. We conclude that the evolution of reproductive isolation in this system cannot proceed without selection against hybrids. Other possible factors facilitating the evolution of isolation would be longer periods of allopatry, the build up of local adaptation or reduced migration upon secondary contact. PMID:21297947

  10. Pyramiding of insecticidal compounds for control of the cowpea bruchid (Callosobruchus maculatus F.).

    PubMed

    Tarver, Matthew R; Shade, Richard E; Shukle, Richard H; Moar, William J; Muir, William M; Murdock, Larry M; Pittendrigh, Barry R

    2007-05-01

    The cowpea bruchid (Callosobruchus maculatus F.) (Chrysomelidae: Bruchini) is a major pest of stored cowpea grain. With limited available technologies for controlling the bruchid, transgenic cowpeas with bruchid resistance genes engineered into them could become the next management tools. An investigation was made of two different sets of potential transgenic insecticidal compounds using an artificial seed system: (i) CIP-PH-BT-J and recombinant egg white avidin, and (ii) avidin and wheat alpha-amylase inhibitor. CIP-PH-BT-J (0.1%; 1000 mg kg(-1)) and recombinant egg white avidin (0.006%; 60 mg kg(-1)) incorporated separately into artificial seeds caused 98.2 and 99% larval mortality rates respectively. Combining CIP-PH-BT-J and avidin in the same artificial seed provided additional mortality compared with each factor incorporated singly; no insects survived in seeds with the combined toxins. Similarly, when avidin and wheat alpha-amylase inhibitor (alphaAI) (1%; 10 g kg(-1)) were incorporated separately into artificial seeds, this caused 99.8 and 98% mortality respectively. However, in combination, avidin and alphaAI did not increase mortality, but they did cause a significant increase in developmental time of the cowpea bruchids. These results emphasize that the joint action of potential insecticidal compounds cannot be predicted from results obtained separately for each compound, and they suggest potential transgenes for further consideration. PMID:17340671

  11. Evaluation of the dust and methanol extracts of Garcinia kolae for the control of Callosobruchus maculatus (F.) and Sitophilus zeamais (Mots)

    PubMed Central

    Ogunleye, R.F.; Adefemi, S.O.

    2007-01-01

    Insecticidal effects of different doses of the dust and methanol extracts of Garcinia kolae on Callosobruchus maculatus and Sitophilus zeamais were tested. The dust had no significant effect on the two insects; none of them died even at 3 d after treatment. The methanol extracts, however, had rapid lethal effects on both C. maculatus and S. zeamais. The mortality of C. maculatus by the lowest concentration of methanol extracts ranged from 95%~100% whereas in S. zeamais, the mortality ranged from 87.5%~100% and 70%~100% in concentrations of 1 g extract+3 ml methanol and 1 g extract+5 ml methanol, respectively, from 24 to 48 h. The least concentration of 1 g extract+15 ml methanol had no significant lethal effect on Sitophilus zeamais. PMID:18257127

  12. The immature stages of Dermestes maculatus, Sarcophaga sp. and Phaenicia sericata as potential paratenic hosts for Trichinella spiralis in nature.

    PubMed

    Riva, Eliana; Fiel, César; Steffan, Pedro

    2015-01-01

    The role of some insect populations in the transmission of Trichinella sp. has been demonstrated. However, most of the studies have been conducted under controlled conditions which may influence the real role that they could play as a paratenic host in nature. To enlight this issue, a series of studies to determine the infective capability of the muscle larva of Trichinella spiralis recovered from immature stages of insect populations that fed on infected tissues exposed to natural conditions were carried out. Mice harbouring T. spiralis muscle larvae (ML) were sacrificed and deposited on a pitfall trap which was established in an open and safe area through 25 days in summer. Necrophilous and necrophagous insects that fed on corpses were recovered, identified and processed to search for live ML of T. spiralis. A complementary study in which maggots of Dermestes maculatus recovered from nature were induced to feed on muscle tissues harbouring T. spiralis larvae was also performed. The muscle larvae recovered from insects at different times of exposition were counted and inoculated to mice to determine the reproductive capability index (RCI). At day 3 of exposition, 29 live ML of T. spiralis were recovered from maggots of Phaenicia sericata. The RCI for these larvae was 133.6. On day 5 of exposition, maggots of Sarcophaga sp. were identified and 17 live T. spiralis larvae were recovered; the RCI of these larvae was 43.4. The T. spiralis ML recovered from maggots of D. maculatus obtained after 2 days of feeding on experimentally infected tissue showed a RCI of 24. The results suggest that larval stages of P. sericata, Sarcophaga sp. and D. maculatus might have an important role as a paratenic host of T. spiralis, which, in terms, may influence the epidemiology of this nematode in endemic areas of trichinellosis. PMID:25346194

  13. Effects of a chitin binding vicilin from Erythrina velutina seeds on bean bruchid pests (Callosobruchus maculatus and Zabrotes subfasciatus).

    PubMed

    Teixeira, Fabiano M; Oliveira, Adeliana S; Macedo, Leonardo L P; Santos, Elizeu A; de Sales, Mauricio P

    2008-01-01

    Erythrina velutina vicilin, EvV, is a dimeric glycoprotein with Mr of 124.6 kDa. EvV was tested for anti-insect activity against bean bruchid larvae. EvV had LD(50) of 0.10% and ED(50) of 0.14% for Z. subfasciatus and LD(50) of 0.26% and ED(50) of 0.19% for C. maculatus. EvV was not digested by bean larvae enzymes until 12 h of incubation, and at 24 h EvV was more resistant to Z. subfasciatus enzymes. PMID:18336356

  14. Extreme positive selection on a new highly-expressed larval glycoprotein (LGP) gene in Galaxias fishes (Osmeriformes: Galaxiidae).

    PubMed

    Wallis, Lise J; Wallis, Graham P

    2011-01-01

    We describe the intron-exon structure and DNA/protein sequences of a new larval glycoprotein (LGP) gene from nine species of galaxiid fish. The gene has a distant similarity to Danio THP (Tamm-Horsfall urinary glycoprotein; uromodulin) and cichlid SPP120 (seminal plasma glycoprotein) due to conserved features of its zona pellucida (ZP) domain, including eight highly conserved cysteines and a consensus furin cleavage site. Using a combination of 454 sequencing of cDNA and exon-primed intron-spanning sequencing of genomic DNA, we obtained full sequences of the coding region (996 bp) and its intervening sequences (1,459 bp). LGP shows an exceptionally strong signal of positive selection over the entire coding region, as evidenced by d(N)/d(S) values >1. Across nine species of Galaxias, 87/332 (26%) amino acid residues are variable, compared with 9/386 (2%) for mitochondrial cytochrome b (cytb) in the same group of species. Across 36 interspecific pairwise comparisons, genetic distances are in all cases larger for coding region than for introns, by a factor of 2.4-fold on average. Reading frame, gene structure, splice sites, and many ZP motifs are conserved across all species. Together with the fact that the gene is expressed in all species, these results argue clearly against the possibility of a pseudogene. We show by 454 sequencing and quantitative polymerase chain reaction that the transcript is abundant (ca. 0.5%) in newly hatched larvae and appears to be almost absent from a range of adult tissues. We postulate that the strong Darwinian evolution exhibited by this protein may reflect some type of immunoprotection at this vulnerable larval stage. PMID:20696791

  15. Echoes of a distant time: effects of historical processes on contemporary genetic patterns in Galaxias platei in Patagonia.

    PubMed

    Vera-Escalona, Iván; Habit, Evelyn; Ruzzante, Daniel E

    2015-08-01

    Interpreting the genetic structure of a metapopulation as the outcome of gene flow over a variety of timescales is essential for the proper understanding of how changes in landscape affect biological connectivity. Here we contrast historical and contemporary connectivity in two metapopulations of the freshwater fish Galaxias platei in northern and southernmost Patagonia where paleolakes existed during the Holocene and Pleistocene, respectively. Contemporary gene flow was mostly high and asymmetrical in the northern system while extremely reduced in the southernmost system. Historical migration patterns were high and symmetric in the northern system and high and largely asymmetric in the southern system. Both systems showed a moderate structure with a clear pattern of isolation by distance (IBD). Effective population sizes were smaller in populations with low contemporary gene flow. An approximate Bayesian computation (ABC) approach suggests a late Holocene colonization of the lakes in the northern system and recent divergence of the populations from refugial populations from east and west of the Andes. For the southern system, the ABC approach reveals that some of the extant G. platei populations most likely derive from an ancestral population inhabiting a large Pleistocene paleolake while the rest derive from a higher-altitude lake. Our results suggest that neither historical nor contemporary processes individually fully explain the observed structure and geneflow patterns and both are necessary for a proper understanding of the factors that affect diversity and its distribution. Our study highlights the importance of a temporal perspective on connectivity to analyse the diversity of spatially complex metapopulations. PMID:26147523

  16. Invasive salmonids and lake order interact in the decline of puye grande Galaxias platei in western Patagonia lakes.

    PubMed

    Correa, Cristian; Hendry, Andrew P

    2012-04-01

    Salmonid fishes, native to the northern hemisphere, have become naturalized in many austral countries and appear linked to the decline of native fishes, particularly galaxiids. However, a lack of baseline information and the potential for confounding anthropogenic stressors have led to uncertainty regarding the association between salmonid invasions and galaxiid declines, especially in lakes, as these have been much less studied than streams. We surveyed 25 lakes in the Aysén region of Chilean Patagonia, including both uninvaded and salmonid-invaded lakes. Abundance indices (AI) of Galaxias platei and salmonids (Salmo trutta and Oncorhynchus mykiss) were calculated using capture-per-unit-effort data from gillnets, minnow traps, and electrofishing. We also measured additional environmental variables, including deforestation, lake morphometrics, altitude, and hydrological position (i.e., lake order). An information-theoretic approach to explaining the AI of G. platei revealed that by far the strongest effect was a negative association with the AI of salmonids. Lake order was also important, and using structural equation modeling, we show that this is an indirect effect naturally constraining the salmonid invasion success in Patagonia. Supporting this conclusion, an analysis of an independent data set from 106 mountain lakes in western Canada showed that introduced salmonids are indeed less successful in low-order lakes. Reproductive failure due to insufficient spawning habitat and harsh environmental conditions could be the cause of these limits to salmonid success. The existence of this effect in Chilean Patagonia suggests that low-order lakes are likely to provide natural ecological refugia for G. platei. Finally, pristine, high-order lakes should be actively protected as these have become rare and irreplaceable unspoiled references of the most diverse, natural lake ecosystems in Patagonia. PMID:22645814

  17. COWPEA WEEVIL (CALLOSOBRUCHUS MACULATUS) FLIGHTS TO A POINT SOURCE OF FEMALE SEX PHEROMONE: ANALYSES OF FLIGHT TRACKS AT THREE WIND SPEEDS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two-day-old male cowpea weevils, Callosobruchus maculatus, were released individually and flew upwind to a point source of female sex pheromone at three wind speeds. All beetles initiating flight along the pheromone plumes made contact with the pheromone source. Analysis of digitized flight tracks i...

  18. Sexual size and shape dimorphism and allometric scaling patterns in head traits in the New Zealand common gecko Woodworthia maculatus.

    PubMed

    Kelly, Clint D

    2015-08-01

    Sexual dimorphism in shape and size is widespread across animal taxa and arises when natural or sexual selection operates differently on the sexes. Male and female common geckos (Woodworthia maculatus; formerly Hoplodactylus maculatus) in New Zealand do not appear to experience different viability selection pressure, nor do males appear to be under intense pre-copulatory sexual selection. It was therefore predicted that this species would be sexually monomorphic with regard to body size and the size and shape of the head. In line with the prediction, there was no sexual difference in head width, depth, or length or in lateral head shape. However, contrary to prediction, males had a larger body and lateral head size than females. This study suggests that males, at least on Maud Island, NZ, might be under stronger pre-copulatory sexual selection than previously recognized and thus have evolved larger heads (i.e. lateral head size) for use in male combat for females. Allometric scaling patterns do not differ between the sexes and suggest that head width and depth are under directional selection whereas lateral head size is under stabilizing selection. Diet ecology - an agent of natural selection common to both sexes - is likely largely responsible for the observed patterns of head size and shape and the lack of sexual dimorphism in them. PMID:25958103

  19. Efficacy of Plectranthus glandulosus (Lamiaceae) and Callistemon rigidus (Myrtaceae) Leaf Extract Fractions to Callosobruchus maculatus (Coleoptera: Bruchidae)

    PubMed Central

    Danga, Simon Pierre Yinyang; Nukenine, Elias Nchiwan; Younoussa, Lame; Adler, Cornel; Esimone, Charles Okechukwu

    2015-01-01

    As part of on-going efforts to use eco-friendly alternatives to chemical pesticides, methanol crude extracts of Plectranthus glandulosus and Callistemon rigidus leaves were sequentially fractionated in hexane, chloroform, ethyl acetate, and methanol to establish the most active fraction(s) against Callosobruchus maculatus in cowpea. Cowpea seeds (25 g) were treated with 0.5, 1, 2, and 4 g/kg of extract to evaluate the contact toxicity and F1 progeny production of the beetles in the laboratory. Mortality was recorded 1, 3, and 7 d postexposure. P. glandulosus hexane fraction was more toxic than the other fractions recording 100% mortality at 4 g/kg, within 7 d with LC50 of 0.39 g/kg. Hexane fraction of C. rigidus showed superior toxicity, causing 100% mortality at 4 g/kg within only 1 d of exposure with LC50 of 1.02 g/kg. All the fractions greatly reduced progeny emergence, with C. rigidus hexane fraction being the best progeny inhibitor. Fractions of P. glandulosus and C. rigidus leaves had sufficient efficacy to be a component of storage pest management package for C. maculatus. PMID:26443776

  20. Chemical Composition and Insecticidal Activity of Essential Oil from Coriandrum sativum Seeds against Tribolium confusum and Callosobruchus maculatus.

    PubMed

    Khani, Abbas; Rahdari, Tahere

    2012-01-01

    The biological activity of essential oil extracted from coriander, Coriandrum sativum L. (Apiaceae), seeds against adults of Tribolium confusum Duval (Coleoptera: Tenebrionidae) and Callosobruchus maculatus F. (Coleoptera: Bruchidae) was investigated in a series of laboratory experiments. Fumigant toxicity was assessed at 27 ± 1°C and 65 ± 5% R.H., in dark condition. Dry seeds of the plant were subject to hydrodistillation using a Clevenger-type apparatus. The composition of essential oil was analyzed by gas chromatography mass spectrometry. The predominant components in the oil were linalool (57.57%) and geranyl acetate (15.09%). The mortality of 1-7-day-old adults of the insect pests increased with concentration from 43 to 357 μL/L air and with exposure time from 3 to 24 h. In the probit analysis, LC(50) values (lethal concentration for 50% mortality) showed that C. maculatus (LC(50) = 1.34 μL/L air) was more susceptible than T. confusum (LC(50) = 318.02 μL/L air) to seed essential oil of this plant. The essential oil of C. sativum can play an important role in stored grain protection and reduce the risks associated with the use of synthetic insecticides. PMID:23227365

  1. Chemical Composition and Insecticidal Activity of Essential Oil from Coriandrum sativum Seeds against Tribolium confusum and Callosobruchus maculatus

    PubMed Central

    Khani, Abbas; Rahdari, Tahere

    2012-01-01

    The biological activity of essential oil extracted from coriander, Coriandrum sativum L. (Apiaceae), seeds against adults of Tribolium confusum Duval (Coleoptera: Tenebrionidae) and Callosobruchus maculatus F. (Coleoptera: Bruchidae) was investigated in a series of laboratory experiments. Fumigant toxicity was assessed at 27 ± 1°C and 65 ± 5% R.H., in dark condition. Dry seeds of the plant were subject to hydrodistillation using a Clevenger-type apparatus. The composition of essential oil was analyzed by gas chromatography mass spectrometry. The predominant components in the oil were linalool (57.57%) and geranyl acetate (15.09%). The mortality of 1–7-day-old adults of the insect pests increased with concentration from 43 to 357 μL/L air and with exposure time from 3 to 24 h. In the probit analysis, LC50 values (lethal concentration for 50% mortality) showed that C. maculatus (LC50 = 1.34 μL/L air) was more susceptible than T. confusum (LC50 = 318.02 μL/L air) to seed essential oil of this plant. The essential oil of C. sativum can play an important role in stored grain protection and reduce the risks associated with the use of synthetic insecticides. PMID:23227365

  2. Efficacy of Plectranthus glandulosus (Lamiaceae) and Callistemon rigidus (Myrtaceae) Leaf Extract Fractions to Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Danga, Simon Pierre Yinyang; Nukenine, Elias Nchiwan; Younoussa, Lame; Adler, Cornel; Esimone, Charles Okechukwu

    2015-01-01

    As part of on-going efforts to use eco-friendly alternatives to chemical pesticides, methanol crude extracts of Plectranthus glandulosus and Callistemon rigidus leaves were sequentially fractionated in hexane, chloroform, ethyl acetate, and methanol to establish the most active fraction(s) against Callosobruchus maculatus in cowpea. Cowpea seeds (25 g) were treated with 0.5, 1, 2, and 4 g/kg of extract to evaluate the contact toxicity and F1 progeny production of the beetles in the laboratory. Mortality was recorded 1, 3, and 7 d postexposure. P. glandulosus hexane fraction was more toxic than the other fractions recording 100% mortality at 4 g/kg, within 7 d with LC50 of 0.39 g/kg. Hexane fraction of C. rigidus showed superior toxicity, causing 100% mortality at 4 g/kg within only 1 d of exposure with LC50 of 1.02 g/kg. All the fractions greatly reduced progeny emergence, with C. rigidus hexane fraction being the best progeny inhibitor. Fractions of P. glandulosus and C. rigidus leaves had sufficient efficacy to be a component of storage pest management package for C. maculatus. PMID:26443776

  3. Effects of insulin and glucagon on plasma glucose levels and glycogen content in organs of the freshwater teleost Pimelodus maculatus.

    PubMed

    Carneiro, N M; Amaral, A D

    1983-01-01

    Mammalian insulin (350 IU/kg) and glucagon (2.5 mg/kg) were injected intraperitoneally into Pimelodus maculatus, a South American teleost. Extent of carbohydrate regulation was estimated through determination of plasma glucose levels, liver-somatic index, and liver and muscle glycogen contents. The effects of insulin administration, examined 6, 12, 24, 48, and 72 hr after injection, were manifested as a depletion of liver glycogen content after 12 hr and severe decrease in plasma glucose content after 24 hr; insulin had no effect on muscle glycogen or liver-somatic index. The effects of glucagon administration, examined 5, 15, 30, 90, and 360 min after injection, were a small increase in liver glycogen content after 15 min, and hyperglycemia, apparent after 30 min. Glucagon did not affect muscle glycogen or liver-somatic index. Control animals were injected intraperitoneally with saline solution. These results suggest that insulin and glucagon regulate the carbohydrate metabolism of P. maculatus by hormonal mechanisms similar to those operating in other teleost species and in mammals. PMID:6337926

  4. Potential of the Lectin/Inhibitor Isolated from Crataeva tapia Bark (CrataBL) for Controlling Callosobruchus maculatus Larva Development.

    PubMed

    Nunes, Natalia N S; Ferreira, Rodrigo S; Silva-Lucca, Rosemeire A; de Sá, Leonardo F R; de Oliveira, Antônia Elenir A; Correia, Maria Tereza dos S; Paiva, Patrícia Maria G; Wlodawer, Alexander; Oliva, Maria Luiza V

    2015-12-01

    Callosobruchus maculatus is an important predator of cowpeas. Due to infestation during storage, this insect affects the quality of seed and crop yield. This study aimed to investigate the effects of CrataBL, a multifunction protein isolated from Crataeva tapia bark, on C. maculatus larva development. The protein, which is stable even in extreme pH conditions, showed toxic activity, reducing the larval mass 45 and 70% at concentrations of 0.25 and 1.0% (w/w), respectively. Acting as an inhibitor, CrataBL decreased by 39% the activity of cysteine proteinases from larval gut. Conversely, the activity of serine proteinases was increased about 8-fold. The toxic properties of CrataBL may also be attributed to its capacity of binding to glycoproteins or glycosaminoglycans. Such binding interferes with larval metabolism, because CrataBL-FITC was found in the fat body, Malpighian tubules, and feces of larvae. These results demonstrate the potential of this protein for controlling larva development. PMID:26568149

  5. [Description of three new monogenean gill parasites from Mormyrus rume (Valenciennes, 1846) (Teleostei: Mormyridae) in Ivory Coast].

    PubMed

    Blahoua, K G; Pariselle, A; N'Douba, V; Kone, T; Kouassi, N J

    2009-03-01

    The study of the gill parasites from elephant fish Mormyrus rume Valenciennes, 1846 (Teleostei: Mormyridae) from the Ayamé man-made Lake (Ivory Coast) revealed the presence of three new monogenean species of the genus Bouixella Euzet & Dossou, 1976, which can be mainly distinguished from all other species of the genus by the morphology and the size of the sclerotised parts of the haptor (dorsal and ventral anchor, dorsal and ventral bar) and by the size and the structure of the male copulatory organ. In this paper, descriptions of Bouixella gorei n. sp., Bouixella yaoi n. sp. and Bouvixella koutouani n. sp. are given. PMID:19353952

  6. Offspring production with cryopreserved sperm from a live-bearing fish Xiphophorus maculatus and implications for female fecundity✰

    PubMed Central

    Yang, Huiping; Savage, Markita G.; Hazlewood, Leona; Walter, Ronald B.; Tiersch, Terrence R.

    2011-01-01

    Xiphophorus fishes are well-established models for biomedical research of spontaneous or induced tumors, and their use in research dates back to the 1930’s. Currently, 58 well-pedigreed lines exist among 24 Xiphophorus species housed as live animals at the Xiphophorus Genetic Stock Center. The technique of sperm cryopreservation has been applied to preserve these valuable genetic resources, and production of offspring has been reported with cryopreserved sperm in two species (X. helleri and X. couchianus). The goal of this research was to establish protocols for sperm cryopreservation and artificial insemination that yield live young in X. maculatus, a widely used research species. The objectives were to: 1) collect basic biological characteristics of males, and quantify the sperm production yield after crushing of dissected testis; 2) cryopreserve sperm from X. maculatus by adapting as necessary the protocols for sperm cryopreservation of X. helleri and X. couchianus; 3) use cryopreserved sperm to inseminate virgin females of X maculatus and other species (X. helleri and X. couchianus), and 4) compare experimental trials over a 3-year period to identify opportunities for improving female fecundity. In total, 117 males were used in this study with a standard length of 2.5 ± 0.3 cm (mean ± SD), body weight of 0.474 ± 0.149 g, and dissected testis weight of 7.1 ± 3.7 mg. Calculation of sperm availability showed 5.9 ± 2.8 × 106 sperm cells per mg of testis weight. Offspring were produced from cryopreserved sperm. Male-to-male variation (1-70%) was observed in post-thaw motility despite little variation in motility before freezing (60-90%) or genetic variation (~100 generations of sib-mating). Comparisons of biological factors of males did not have significant correlations with the production of live young, and the influence of females on production of young were identified from the comparison of artificial insemination over the 3 yr. Overall, this study describes offspring production from cryopreserved sperm in a third species of Xiphophorus fishes, and identifies the opportunities for improving female fecundity which is essential for establishment of germplasm repositories for Xiphophorus fishes. PMID:21616165

  7. Effect of some metal ions on blood and liver delta-aminolevulinate dehydratase of Pimelodus maculatus (Pisces, Pimelodidae).

    PubMed

    Rodrigues, A L; Bellinaso, M L; Dick, T

    1989-01-01

    1. delta-ALA-D from Pimelodus maculatus was inhibited in vitro by Cd2+ greater than Pb2+ greater than Hg2+ greater than Cu2+ greater than Zn2+ in blood and by Pb2+ greater than Cd2+ greater than Hg2+ greater than Cu2+ = Zn2+ in the liver. 2. Kinetic analysis of the inhibition by the metal ions showed that Cd2+ and Hg2+ act as non-competitive inhibitors on both sources. 3. Pb2+ showed a mixed type of inhibition in blood and a non-competitive type in the liver. 4. Zn2+ acted as a competitive or mixed inhibitor, on both sources, depending on concentration. PMID:2598636

  8. Variant vicilins from a resistant Vigna unguiculata lineage (IT81D-1053) accumulate inside Callosobruchus maculatus larval midgut epithelium.

    PubMed

    Oliveira, Gabriel B; Kunz, Daniele; Peres, Tanara V; Leal, Rodrigo B; Uchôa, Adriana F; Samuels, Richard I; Macedo, Maria Lígia R; Carlini, Célia R; Ribeiro, Alberto F; Grangeiro, Thalles B; Terra, Walter R; Xavier-Filho, José; Silva, Carlos P

    2014-02-01

    It has been demonstrated that variant vicilins are the main resistance factor of cowpea seeds (Vigna unguiculata) against attack by the cowpea beetle Callosobruchus maculatus. There is evidence that the toxic properties of these storage proteins may be related to their interaction with glycoproteins and other microvillar membrane constituents along the digestive tract of the larvae. New findings have shown that following interaction with the microvilli, the vicilins are absorbed across the intestinal epithelium and thus reach the internal environment of the larvae. In the present paper we studied the insecticidal activity of the variant vicilins purified from a resistant cowpea variety (IT81D-1053). Bioassays showed that the seeds of this genotype affected larval growth, causing developmental retardation and 100% mortality. By feeding C. maculatus larvae on susceptible and IT81D-1053 derived vicilins (FITC labelled or unlabelled), followed by fluorescence and immunogold cytolocalization, we were able to demonstrate that both susceptible and variant forms are internalized in the midgut cells and migrate inside vesicular structures from the apex to the basal portion of the enterocytes. However, when larvae were fed with the labelled vicilins for 24h and then returned to a control diet, the concentration of the variant form remained relatively high, suggesting that variant vicilins are not removed from the cells at the same rate as the non-variant vicilins. We suggest that the toxic effects of variant vicilins on midgut cells involve the binding of these proteins to the cell surface followed by internalization and interference with the normal physiology of the enterocytes, thereby affecting larval development in vivo. PMID:24220155

  9. Genetic characterization of hatchery populations of Korean spotted sea bass (Lateolabrax maculatus) using multiplex polymerase chain reaction assays.

    PubMed

    An, H S; Kim, H Y; Kim, J B; Chang, D S; Park, K D; Lee, J W; Myeong, J I; An, C M

    2014-01-01

    The spotted sea bass, Lateolabrax maculatus, is an important commercial and recreational fishery resource in Korea. Aquacultural production of this species has increased because of recent resource declines, growing consumption, and ongoing government-operated stock release programs. Therefore, the genetic characterization of hatchery populations is necessary to maintain the genetic diversity of this species and to develop more effective aquaculture practices. In this study, the genetic diversity and structure of three cultured populations in Korea were assessed using multiplex assays with 12 highly polymorphic microsatellite loci; 144 alleles were identified. The number of alleles per locus ranged from 6 to 28, with an average of 13.1. The mean observed and expected heterozygosities were 0.724 and 0.753, respectively. Low levels of inbreeding were detected according to the inbreeding coefficient (mean FIS = 0.003-0.073). All hatchery populations were significantly differentiated from each other (overall fixation index (FST) = 0.027, P < 0.01), and no population formed a separate cluster. Pairwise multilocus FST tests, estimates of genetic distance, mantel test, and principal component analyses did not show a consistent relationship between geographic and genetic distances. These results could reflect the exchange of breeds and eggs between hatcheries and/or genetic drift due to intensive breeding practices. For optimal resource management, the genetic variation of hatchery stocks should be monitored and inbreeding controlled within the spotted sea bass stocks that are being released every year. This genetic information will be useful for the management of both L. maculatus fisheries and the aquaculture industry. PMID:25177950

  10. A new species of Unilatus (Platyhelminthes: Monogenoidea) from the gills of Leporacanthicus galaxias Isbrücker et Nijssen (Siluriformes: Loricariidae) from Brazil.

    PubMed

    Branches, Bárbara; Domingues, Marcus V

    2014-03-01

    Unilatus irae sp. nov. (Dactylogyridae) is described from the gills of the armored catfish, Leporacanthicus galaxias Isbrücker et Nijssen (Loricariidae: Ancistrinae), from Guamá river, Pará State, Brazil. The new species can be differentiated from its cogeneners by the combination of the following features: anterior anchor with well-developed superficial root, inconspicuous deep root, shaft bent at midpoint, forming angle of approximately 60°, evenly short curved point; posterior anchor with inconspicuous roots, sclerotized cap of base with small protuberance for articulation to posterior bar; evenly curved shaft and short point; anterior bar broadly V-shaped, with small posteromedial projection; and posterior bar anteriorly expanded on it midportion, with expanded ends slightly curved in posterior direction. PMID:24570054

  11. Molecular systematics of the enigmatic Middle American genus Vieja (Teleostei: Cichlidae).

    PubMed

    McMahan, Caleb D; Geheber, Aaron D; Piller, Kyle R

    2010-12-01

    The genus Vieja represents a group of heroine cichlids (Teleostei: Cichlidae) distributed on the Atlantic and Pacific slopes of North and Central America from southern Mexico to Panama. Sixteen species of Vieja are presently recognized; however, based on long-standing taxonomic problems, the genus itself appears to be weakly defined. A number of different generic designations have been proposed for members of Vieja, and recent systematic studies of heroine cichlids have not specifically addressed the validity of the grouping and have not included all species in the genus. Therefore, the purpose of this study was to assess the monophyly of the genus Vieja by including all nominal species in the genus using the mitochondrial encoded cytochrome b gene and nuclear S7-1 intron. Results of Maximum Parsimony, Bayesian inference, and topology tests (constraint tree searches and post-burn-in Bayesian filtering) indicate that the genus is not monophyletic as it is currently recognized. The genus Herichthys was recovered as sister to a clade consisting of a number of Vieja species (V. fenestrata, V. guttulata, V. zonata, V. hartwegi, V. bifasciata, V. breidohri, V. argentea, V. regani, V. melanura, V. synspila, and V. maculicauda, as well as Paraneetroplusbulleri). A clade consisting of V. intermedia, V. godmanni, and V. microphthalma was recovered sister to Theraps. Additionally, V. heterospila and V. tuyrensis were recovered outside of Vieja and Herichthys clades. Based on the results of this comprehensive study, we suggest a revised classification of Vieja species. PMID:20849962

  12. Improved resolution and a novel phylogeny for the Neotropical triplefin blennies (Teleostei: Tripterygiidae).

    PubMed

    Miller, Elizabeth Christina; Lin, Hsiu-Chin; Hastings, Philip A

    2016-03-01

    The triplefin blennies (Teleostei: Tripterygiidae) are a diverse group of small-bodied benthic fishes associated with rocky or coral reefs. The Neotropics contain four genera and 26 species, many of which have only been recently described. A recent molecular phylogeny (Lin and Hastings, 2013) contrasts with previous phylogenies based on morphology in recovering the four Neotropical genera as a single clade with respect to the Indo-Pacific genera; however, relationships within and among genera were poorly resolved. This study reports a novel topology based on an expanded seven-loci molecular dataset. Individual gene trees have poor resolution, but concatenated analyses show strong support for most nodes, likely due to emergent support from concatenation. Consistent with Lin and Hastings (2013), three of the Neotropical genera, Axoclinus, Enneanectes, and Crocodilichthys, form a well-supported clade, but relationships of the fourth (Lepidonectes) are not confidently resolved. The monophyly of Axoclinus is well supported, but Enneanectes is paraphyletic with the inclusion of Axoclinus and Crocodilichthys. Improved resolution allows for reinterpretation of the biogeography of the Neotropical Tripterygiidae. Broader taxon sampling is still necessary for resolving the relationships within Tripterygiidae globally. PMID:26718057

  13. New species of Cerambycinae from the Neotropical Region, and nomen novum for Anelaphus maculatus Galileo, Martins, and Santos-Silva, 2014 (Elaphidiini).

    PubMed

    Galileo, Maria Helena M; Martins, Ubirajara R; Santos-Silva, Antonio

    2015-01-01

    Six new species and one new genus are described: Criodion spinosum sp. nov. (Cerambycini), from Bolivia; Eburodacrys wappesi sp. nov. and Eburodacrys skillmani sp. nov. (Eburiini), from Bolivia; Eupempelus rileyorum sp. nov. (Heteropsini) from Panama; Sphalloeme mexicana sp. nov. (Oemini), from Mexico; Wappesoeme camiri sp. nov., new genus (Oemini), from Bolivia. Wappesoeme, Eburodacrys wappesi, E. skillmani, Eupempelus rileyorum, and Criodion spinosum are included in previously published keys. Anelaphus erakyra nomen novum for A. maculatus Galileo et al., 2014 is established. PMID:26250192

  14. Bioefficacy of a long-lasting insecticide impregnated net on blood feeding inhibition of Anopheles maculatus Theobald and Culex quinquefasciatus Say.

    PubMed

    Beng, Tan Swee; Vythilingam, Indra; Lim, Lee Han

    2014-05-01

    This study aimed to evaluate the bioefficacy and blood feeding inhibition of mosquitoes under laboratory conditions using the WHO tunnel test method on unwashed and washed long-lasting insecticide impregnated net with extrinsic heat treatment of 30 degrees C followed by 80 degrees C on the same net during washing. PermaNet exhibited fairy high durability to washing (5 washes) and had fairy long-lasting bioefficacy against Anopheles maculatus for blood feeding inhibition on both unwashed (39 months) and washed (26 months) nets. However, Perma-Net exhibited lower bioefficacy against Culex quinquefasciatus. This study also suggested that the application of extrinsic heat treatment of 30 degrees C followed by an increased heat at 80 degrees C on the same net exerted significant differences (p < 0.05) in mortality of both An. maculatus and Cx. quinquefasciatus. However, extrinsic heat treatment did not enhance any significant increase in blood feeding inhibition of both An. maculatus and Cx. quinquefasciatus (p > 0.05). An. maculatus exhibited significant differences in resting preference after a successful blood meal, as more blood-fed and live females preferred to rest and stay near the bait in the mouse cage, and more dead and unfed females were found in the outer cage of both the unwashed and washed nets (p < 0.05). Conversely, fully blood-fed and live Cx. quinquefasciatus females did not show any resting preference between the mouse cage and outer cage, but there were more dead and unfed females in the mouse cage of both the unwashed and washed nets (p < 0.05). PMID:24974644

  15. Niche preferences and spatial distribution of Monogenea on the gills of Pimelodus maculatus in Río de la Plata (Argentina).

    PubMed

    Gutiérrez, P A; Martorelli, S R

    1999-08-01

    Five Monogenea species were found on the gills of the catfish Pimelodus maculatus in Río de la Plata (Argentina). These were used for studying the preference of species on different gill-hemibranches, niche breadth and niche overlap between species. It was found that congeneric species had a generic-specific preference for certain gill-hemibranches. Niche breadth appeared to be related to the number of individuals of each species. Niche overlap between the species is discussed. PMID:10466126

  16. Purification, partial characterization and role in lipid transport to developing oocytes of a novel lipophorin from the cowpea weevil, Callosobruchus maculatus.

    PubMed

    Ximenes, A A; Oliveira, G A; Bittencourt-Cunha, P; Tomokyo, M; Leite, D B; Folly, E; Golodne, D M; Atella, G C

    2008-01-01

    Lipid transport in arthropods is achieved by highly specialized lipoproteins, which resemble those described in vertebrate blood. Here we describe purification and characterization of the lipid-apolipoprotein complex, lipophorin (Lp), from adults and larvae of the cowpea weevil Callosobruchus maculatus. We also describe the Lp-mediated lipid transfer to developing oocytes. Lps were isolated from homogenates of C. maculatus larvae and adults by potassio bromide gradient and characterized with respect to physicochemical properties and lipid content. The weevil Lp (465 kDa) and larval Lp (585 kDa), with hydrated densities of 1.22 and 1.14 g/mL, contained 34 and 56% lipids and 9 and 7% carbohydrates, respectively. In both Lps, mannose was the predominant monosaccharide detected by paper chromatography. SDS-PAGE revealed two apolipoproteins in each Lp with molecular masses of 225 kDa (apolipoprotein-I) and 79 kDa (apolipoprotein-II). The lipids were extracted and analyzed by thin-layer chromatography. The major phospholipids found were phosphatidylserine, phosphatidylcholine and phosphatidylethanolamine in adult Lp, and phosphatidylcholine, phosphatidylethanolamine and sphingomyelin in larval Lp. Hydrocarbons, fatty acids and triacylglycerol were the major neutral lipids found in both Lps. Lps labeled in the protein moiety with radioactive iodine (125I-iodine) or in the lipid moiety with fluorescent lipids revealed direct evidence of endocytic uptake of Lps in live oocytes of C. maculatus. PMID:18038102

  17. Effects of Phaseolus vulgaris (Fabaceae) seed coat on the embryonic and larval development of the cowpea weevil Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    de Sá, Leonardo Figueira Reis; Wermelinger, Tierry Torres; Ribeiro, Elane da Silva; Gravina, Geraldo de Amaral; Fernandes, Kátia Valevski Sales; Xavier-Filho, José; Venancio, Thiago Motta; Rezende, Gustavo Lazzaro; Oliveira, Antonia Elenir Amancio

    2014-01-01

    Bruchid beetles infest various seeds. The seed coat is the first protective barrier against bruchid infestation. Although non-host seed coats often impair the oviposition, eclosion and survival of the bruchid Callosobruchus maculatus larvae, morphological and biochemical aspects of this phenomenon remain unclear. Here we show that Phaseolus vulgaris (non-host) seed coat reduced C. maculatus female oviposition about 48%, increased 83% the seed penetration time, reduced larval mass and survival about 62 % and 40 % respectively. Interestingly, we found no visible effect on the major events of insect embryogenesis, namely the formation of the cellular blastoderm, germ band extension/retraction, embryo segmentation, appendage formation and dorsal closure. Larvae fed on P. vulgaris seed coat have greater FITC fluorescence signal in the midgut than in the feces, as opposed to what is observed in control larvae fed on Vigna unguiculata. Cysteine protease, α-amylase and α-glucosidase activities were reduced in larvae fed on P. vulgaris natural seed coat. Taken together, our results suggest that although P. vulgaris seed coat does not interfere with C. maculatus embryonic development, food digestion was clearly compromised, impacting larval fitness (e.g. body mass and survivability). PMID:24211390

  18. Estudio de la formación de galaxias espirales en un modelo de agregación jerárquica

    NASA Astrophysics Data System (ADS)

    Tissera, P.; Saiz, A.; Dominguez-Tenreiro, R.

    El estudio de formación de galaxias espirales ha llevado al desarrollo de numerosos modelos teóricos (e.g. White & Rees 1978). En la actualidad, el modelo más aceptado predice la formación de una galaxia espiral a partir del colapso disipativo del gas en el pozo de potencial de un halo oscuro, conservando su momento angular específco (Fall & Efstathiou 1980). En los últimos años, ha sido posible realizar simulaciones numéricas hidrodinámicas, las cuales describen la evolución conjunta de la materia oscura y los bariones. Estos experimentos han señalado la dificultad de formar estructuras discoidales con propiedades consistentes con las observaciones, en modelos de agregación jerárquica. El problema principal se origina en la pérdida catastrófica de momento angular de la componente disipativa, durante el proceso de ensamblaje de los objetos, a través de la fusión de subestructura (Navarro & Steinmetz 1997). Estos experimentos no incluían procesos de formación estelar. En este trabajo, se expondrán resultados de simulaciones hidrodinámicas cosmológicas, incluyendo formación estelar (Tissera et al 1997), donde ha sido posible reproducir objetos discoidales con contrapartida observacional. El elemento fundamental ha sido la formación de bulbos estelares, los cuales han evitado la pérdida catastrófica de momento angular de los bariones. Se encontró que los discos exponenciales puramente gaseosos son altamente inestables y suceptibles de generar barras, responsables de la pérdida de momento angular y la caída violenta del gas hacia la región central. Estas inestabilidades son fácilmente inducidas durante interacciones y fusiones con objetos vecinos (Barnes & Hernquist 1996). Un bulbo estelar (o un objeto masivo y compacto) estabiliza el disco ante perturbaciones externas, asegurándole un potencial simétrico (Sellwood & Moore 1998, Van der Bosch 1998). En este caso, el gas en el disco no pierde completamente su momento angular intrínseco durante las fusiones, sino que, las sobrevive aportando una contribución distinta de cero, a partir de la cual el disco se regenera acretando en una segunda etapa, gas del halo de acuerdo al modelo tradicional de Fall & Efstathiou.

  19. A screen for bacterial endosymbionts in the model organisms Tribolium castaneum, T. confusum, Callosobruchus maculatus, and related species.

    PubMed

    Goodacre, Sara L; Fricke, Claudia; Martin, Oliver Y

    2015-04-01

    Reproductive parasites such as Wolbachia are extremely widespread amongst the arthropods and can have a large influence over the reproduction and fitness of their hosts. Undetected infections could thus confound the results of a wide range of studies that focus on aspects of host behavior, reproduction, fitness, and degrees of reproductive isolation. This potential problem has already been underlined by work investigating the incidence of Wolbachia infections in stocks of the model system Drosophila melanogaster. Here we survey a range of lab stocks of further commonly used model arthropods, focusing especially on the flour beetles Tribolium castaneum and Tribolium confusum, the cowpea weevil Callosobruchus maculatus and related species (Coleoptera: Tenebrionidae and Bruchidae). These species are widespread stored product pests so knowledge of infections with symbionts further has potential use in informing biocontrol measures. Beetles were assessed for infection with 3 known microbial reproductive parasites: Wolbachia, Rickettsia, Spiroplasma. Infections with some of these microbes were found in some of the lab stocks studied, although overall infections were relatively rare. The consequences of finding infections in these or other species and the type of previous studies likely to be affected most are discussed. PMID:24347564

  20. Influence of environmental temperature on the fatty acid desaturation and elongation activity of fish (Pimelodus maculatus) liver microsomes.

    PubMed

    de Torrengo, M; Brenner, R R

    1976-01-22

    The effect of environmental temperature on the activity of liver microsomes of fish (Pimelodus maculatus) to desaturate and elongate oleic, linoleic and alpha-linolenic acids was studied. It was found that: 1. Fish kept at 14-15 degrees C had higher desaturation and elongation activity than animals kept at 29-30 degrees C. The ratio of activity was the same for the three fatty acids. 2. A decrease of the environmental temperature increased the V of linoleic acid desaturation to gamma-linolenic acid, but did not modify the approximate Km of the reaction. 3. The inactivation of the delta6-desaturase of microsomes separated from fish kept at 29-30 degrees C and 14-15 degrees C was the same when heated at 40 degrees C. However, the enzyme was deactivated faster when heated at 29-30 degrees C than at 14-15 degrees C. 4. The increase of the delta6-desaturation activity of the microsomes evoked by the decrease of the temperature of the aquarium was mostly compensated for by the correlative decrease of the specific reaction rate of the reaction. For this reason it is assumed that the adaptive change of the desaturation activity of the microsomes with the environmental temperature does not greatly modify the fatty acid composition of the fish. PMID:1252479

  1. Sex-specific genetic variances in life-history and morphological traits of the seed beetle Callosobruchus maculatus

    PubMed Central

    Hallsson, Lára R; Björklund, Mats

    2012-01-01

    Knowledge of heritability and genetic correlations are of central importance in the study of adaptive trait evolution and genetic constraints. We use a paternal half-sib-full-sib breeding design to investigate the genetic architecture of three life-history and morphological traits in the seed beetle, Callosobruchus maculatus. Heritability was significant for all traits under observation and genetic correlations between traits (rA) were low. Interestingly, we found substantial sex-specific genetic effects and low genetic correlations between sexes (rMF) in traits that are only moderately (weight at emergence) to slightly (longevity) sexually dimorphic. Furthermore, we found an increased sire () compared to dam () variance component within trait and sex. Our results highlight that the genetic architecture even of the same trait should not be assumed to be the same for males and females. Furthermore, it raises the issue of the presence of unnoticed environmental effects that may inflate estimates of heritability. Overall, our study stresses the fact that estimates of quantitative genetic parameters are not only population, time, environment, but also sex specific. Thus, extrapolation between sexes and studies should be treated with caution. PMID:22408731

  2. Genetic variability and resistance of cultivars of cowpea [Vigna unguiculata (L.) Walp] to cowpea weevil (Callosobruchus maculatus Fabr.).

    PubMed

    Vila Nova, M X; Leite, N G A; Houllou, L M; Medeiros, L V; Lira Neto, A C; Hsie, B S; Borges-Paluch, L R; Santos, B S; Araujo, C S F; Rocha, A A; Costa, A F

    2014-01-01

    The cowpea weevil (Callosobruchus maculatus Fabr.) is the most destructive pest of the cowpea bean; it reduces seed quality. To control this pest, resistance testing combined with genetic analysis using molecular markers has been widely applied in research. Among the markers that show reliable results, the inter-simple sequence repeats (ISSRs) (microsatellites) are noteworthy. This study was performed to evaluate the resistance of 27 cultivars of cowpea bean to cowpea weevil. We tested the resistance related to the genetic variability of these cultivars using ISSR markers. To analyze the resistance of cultivars to weevil, a completely randomized test design with 4 replicates and 27 treatments was adopted. Five pairs of the insect were placed in 30 grains per replicate. Analysis of variance showed that the number of eggs and emerged insects were significantly different in the treatments, and the means were compared by statistical tests. The analysis of the large genetic variability in all cultivars resulted in the formation of different groups. The test of resistance showed that the cultivar Inhuma was the most sensitive to both number of eggs and number of emerged adults, while the TE96-290-12-G and MNC99-537-F4 (BRS Tumucumaque) cultivars were the least sensitive to the number of eggs and the number of emerged insects, respectively. PMID:24737480

  3. An Anomalous Hatchery-Reared Biwa Rock Catfish, Silurus lithophilus (Teleostei: Siluridae),with an Adipose Fin-Like Projection.

    PubMed

    Kitagawa, Tetsuro; Hosoya, Kazumi

    2015-10-01

    An anomalous individual with an adipose fin-like projection was discovered during seedling production of Biwa rock catfish, Silurus lithophilus (Teleostei: Siluridae). The external shape of the projection resembled an adipose fin, but soft rays were clearly observed within it. The projection was proximally supported by a series of pterygiophores and by 14 soft rays. The projection can be explained as: I, homologous with a primitive adipose fin, which occurred as a result of localized ontogenetic reversion; II, an extra fin that occurred as a result of abnormal expression of a regeneration mechanism; III, a remnant of a dorsal fin and/or a second dorsal fin; and IV, an inversion phenomenon of the polarity in the formation process of the anal fin. PMID:26428720

  4. Across the southern Andes on fin: glacial refugia, drainage reversals and a secondary contact zone revealed by the phylogeographical signal of Galaxias platei in Patagonia.

    PubMed

    Zemlak, Tyler S; Habit, Evelyn M; Walde, Sandra J; Battini, Miguel A; Adams, Emily D M; Ruzzante, Daniel E

    2008-12-01

    We employed DNA sequence variation at two mitochondrial (control region, COI) regions from 212 individuals of Galaxias platei (Pisces, Galaxiidae) collected throughout Patagonia (25 lakes/rivers) to examine how Andean orogeny and the climatic cycles throughout the Quaternary affected the genetic diversity and phylogeography of this species. Phylogenetic analyses revealed four deep genealogical lineages which likely represent the initial division of G. platei into eastern and western lineages by Andean uplift, followed by further subdivision of each lineage into separate glacial refugia by repeated Pleistocene glacial cycles. West of the Andes, refugia were likely restricted to the northern region of Patagonia with small relicts in the south, whereas eastern refugia appear to have been much larger and widespread, consisting of separate northern and southern regions that collectively spanned most of Argentinean Patagonia. The retreat of glacial ice following the last glacial maximum allowed re-colonization of central Chile from nonlocal refugia from the north and east, representing a region of secondary contact between all four glacial lineages. Northwestern glacial relicts likely followed pro-glacial lakes into central Chilean Patagonia, whereas catastrophic changes in drainage direction (Atlantic --> Pacific) for several eastern palaeolakes were the likely avenues for invasions from the east. These mechanisms, combined with evidence for recent, rapid and widespread population growth could explain the extensive contemporary distribution of G. platei throughout Patagonia. PMID:19017262

  5. Effects of a chitin-binding vicilin from Enterolobium contortisiliquum seeds on bean bruchid pests (Callosobruchus maculatus and Zabrotes subfasciatus) and phytopathogenic fungi (Fusarium solani and Colletrichum lindemuntianum).

    PubMed

    Moura, Fabiano T; Oliveira, Adeliana S; Macedo, Leonardo L P; Vianna, André L B R; Andrade, Lucia B S; Martins-Miranda, A S; Oliveira, Jose T A; Santos, Elizeu A; de Sales, Mauricio P

    2007-01-24

    Chitin-binding vicilin from Enterolobium contortisiliquum seeds was purified by ammonium sulfate followed by gel filtration on Sephacryl 300-SH and on Sephacryl 200-SH. The vicilin, called EcV, is a dimeric glycoprotein composed of 1.03% carbohydrates and a Mr of 151 kDa, consisting of two subunits of Mr of 66.2 and 63.8 kDa. The EcV homogeneity was confirmed in a PAGE where it was observed to be a unique acid protein band with slow mobility in this native gel. E. contortisiliquum vicilin (EcV) was tested for anti-insect activity against C. maculatus and Zabrotes subfasciatus larvae and for phytopathogenic fungi, F. solani and C. lindemuntianum. EcV was very effective against both bruchids, producing 50% mortality for Z. subfasciatus at an LD50 of 0.43% and affected 50% of the larvae mass with an ED50 of 0.65%. In artificial diets given to C. maculatus, 50% of the larvae mass was affected with an ED50 of 1.03%, and larva mortality was 50% at LD50 of 1.11%. EcV was not digested by midgut homogenates of C. maculatus and Z. Subfasciatus until 12 h of incubation, and at 24 h EcV was more resistant to Z. subfasciatus larval proteases. The binding to chitin present in larvae gut associated to low EcV digestibility could explain its lethal effects. EcV also exerted an inhibitory effect on the germination of F. solani at concentrations of 10 and 20 microg mL-1. The effect of EcV on fungi is possibly due to binding to chitin-containing structures of the fungal cell wall. PMID:17227051

  6. Effect of diatomaceous earths Fossil Shield and Silico-Sec on the egg laying behaviour of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae).

    PubMed

    Prasantha, B D Rohitha; Reichmuth, Ch; Büttner, C

    2002-01-01

    The pulse beetle, Callosobruchus maculatus (F.) is a destructive pest of pulses in both storage and field. It is well known that diatomaceous earth (DE) kill the insects by locally absorbing the epicuticular lipid layers leading to high rate of water loss through the cuticle. However, the effectiveness of DE depends on its ability to kill the adults before copulation and egg-laying. Newly emerged virgin males and females of Callosobruchus maculatus (F.) were exposed to the DEs, Fossil-Shield and Silico-Sec on 30 treated mungbeans (Vigna radita (L)). Fecundity, number of beans used for egg-laying and beans without eggs were evaluated after four days; the number of unhatched eggs was evaluated after ten days. It was determined, that the fecundity of female insects decreased sigmoidely with increasing rate of DE content. Percentages of unhatched eggs and seeds without eggs increased with increasing DE dosages. However, the maximum egg densities (eggs per used secd) occurred at 1200 mg DE/kg for Fossil-Shield and Silico-Sec. The reason for such DE-stimulated behaviour of egg laying expressed as a number of seeds with eggs of C. maculatus is not known, but it may be related to the stress caused by the inert dusts or to the reduction of both chemical and physical (tactile) stimuli. Treatment with DEs altered the surface texture of the beans and caused less cohesion between eggs and the seed surface. Only few larvae managed to penetrate into the grains, possibly due to increased grain roughness and repellent effect of DE. A relatively high number of eggs were laid on the surface of those beans where the amount of dust had been locally reduced by adults' movement and their pick up of DE. Therefore, several larvae tried to penetrate into these treated beans, causing a high larval density per partially cleaned bean. All these reasons lead to a progeny decline. PMID:12703482

  7. Isolation and purification of a papain inhibitor from Egyptian genotypes of barley seeds and its in vitro and in vivo effects on the cowpea bruchid, Callosobruchus maculatus (F.).

    PubMed

    Abd El-Latif, Ashraf Oukasha

    2015-02-01

    The cysteine inhibitors that are known as cystatin have been identified and characterized from several plant species. In the current study, 44 barley (Hordeum vulgare) genotypes including 3 varieties and 41 promising lines were screened for their potential as protease inhibitors. The barley genotypes showed low inhibitory activity against trypsin and chymotrypsin enzymes with a mean of 4.15 TIU/mg protein and 4.40 CIU/mg protein. The barley variety, Giza 123, showed strong papain inhibitory activity of 97.09 PIU/mg proteins and was subjected for further purification studies using ammonium sulfate fractionation and DEAE-Sephadex A-25 column. Barley purified proteins showed two bands on SDS-PAGE corresponding to a molecular mass of 12.4-54.8 kDa. The purified barley PI was found to be stable at a temperature below 80 °C and at a wide range of pH from 2 to 12. Barley PI was found to have higher potential inhibitory activity against papain enzyme compared to the standard papain inhibitor, E-64 with an IC50 value of 21.04 µg/ml and 25.62 µg/ml for barley PI and E-64, respectively. The kinetic analysis revealed a non-competitive type of inhibition with a Ki value of 1.95 × 10(-3 )µM. The antimetabolic effect of barley PI was evaluated against C. maculatus by incorporating the F30-60 protein of the purified inhibitor into the artificial diet using artificial seeds. Barley PI significantly prolonged the development of C. maculatus in proportion to PI concentration. Barley PI significantly increased the mortality of C. maculatus and caused a significant reduction in its fecundity. On the other hand, barley PI seemed to have non-significant effects on the adult longevity and the adult dry weight. The in vitro and in vivo results proved the efficiency of the papain inhibitory protein isolated from barley as a tool for managing the cowpea bruchid, C. maculatus. PMID:25752426

  8. The life-cycle of the digenetic trematode, Proctoeces maculatus (Looss, 1901) Odhner, 1911 (Syn. P. rubtenuis [Linton, 1907] Hanson, 1950), and description of Cerceria adranocerca n. sp

    USGS Publications Warehouse

    Stunkard, H.W.; Uzmann, J.R.

    1959-01-01

    The genus Proctoeces was erected by Odhner ( 191 1) to contain Distonium maculatuni Looss, 1901, from Labrus merula and Crenilabrus spp. at Triest. Odhner had found the parasite in Blennius ocellaris at Naples. One adult specimen from Chrysophrys bifasciata and two immature specimens from lulis lunaris taken in the Red Sea, were described as a new species, Proctoeces erythraeus. Dawes (1946) listed P. erythraeus as a synonym of  P. maculatus (Looss) , but the species was recognized by Manter ( 1947) on the basis of six specimens he had collected from Calamus calamus and Calamus bajonado at the biological laboratory of the Carnegie Institution at Dry Tortugas, Florida. Several additional species have been de scribed. Fujita ( 1925) reported a metacercaria from the Japanese oyster, Ostrea gigas, as a new species, Proctoeces ostreae. The paper was translated by R. Ph. Dollfus who noted (p. 57) ,“Il est à souhaiter que des recherches chez les poissons mangers de Lamellibranches, sur les côtes de la préfecture d'Hiroshima, permettent de découvrir des exemplaires complètement adultes de Proctoeces ostreae Fuj., chez lesquels l'extension des vitellogènes et les dimensions des oeufs puissent être observées avec précision; il sera alors possible de savoir définitivement si P. ostreae Fuj. doit ou non tomber en synonymie avec P. maculatus (Looss)." Yamaguti (1934) described P. maculatus from Sparus aries, Sparws macrocephalus, Pagrosomus auratus, and Epinephelus akaara in Japan. Several specimens from Pagrosomus auratus, which differed from P. maculatus in larger size, larger eggs, and trilobed ovary, he described as a new species, Proctoeces major. Yamaguti ( 1938) reported P. nzaculatus from Sensicossyphus reticulatus and described a larva from the liver of the pelecypod mollusk, Brachidontes senhausi, as an unidentified member of the genus Proctoeces. Manter ( 1940) described Proctoeces tnagnorus from a single specimen found in the intestine of Caulolatilus ano,nalus, taken at Cerros Island, Mexico. Hanson ( 1950) identified two specimens collected from Calamus sp. at Bermuda by the late F. D. Barker as Distontuni subtenue Linton, 1907, a species described originally from Calantus calanius in the same area. Comparison of these specimens with those from Tortugas identified by Manter as P. erythraeus established their identity, and P. erythraeus was suppressed as a synonym of Proctoeces subtenue (Linton, 1907). Hanson corrected the statement of Manter (1947), noting that it is the vitellaria, not the uterus, which never extends into the post testicular region.

  9. The distribution of neuropeptide Y and dynorphin immunoreactivity in the brain and pituitary gland of the platyfish, Xiphophorus maculatus, from birth to sexual maturity

    NASA Technical Reports Server (NTRS)

    Cepriano, L. M.; Schreibman, M. P.

    1993-01-01

    Immunoreactive neuropeptide Y and dynorphin have been localized in the brain and pituitary gland of the platyfish, Xiphophorus maculatus, at different ages and stages of development from birth to sexual maturity. Immunoreactive neuropeptide Y was found in perikarya and tracts of the nucleus olfactoretinalis, telencephalon, ventral tegmentum and in the neurohypophysis and in the three regions of the adenohypophysis. Immunoreactive dynorphin was found in nerve tracts in the olfactory bulb and in cells of the pars intermedia and the rostral pars distalis of the pituitary gland.

  10. 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 for only 5 parasites; but two species may be transmitted to larger fish, and 6 species to sea birds or mammals. The parasite community of the five gobies may possibly be taken to characterize the ecological quality of the environment of the Lübeck Bight.

  11. Metazoan parasites of Mandi-amarelo Pimelodus maculatus and of Jundiá Rhamdia quelen (Osteichthyes: Siluriformes) of Paraíba do Sul River, Volta Redonda, Rio de Janeiro.

    PubMed

    Venancio, Aline Cristine Pinto; de Aguiar, Gesilene Ribeiro; Lopes, Patrícia da Silva; Alves, Dimitri Ramos

    2010-01-01

    Forty-one specimens of mandi-amarelo Pimelodus maculatus Lacépède, 1803 (Siluriformes: Pimelodidae) and 54 specimens of jundiá Rhamdia quelen (Quoy & Gaimard, 1824) (Siluriformes: Heptapteridae) were collected from the Paraíba do Sul River, Volta Redonda, State of Rio de Janeiro, Brazil between November 2007 and October 2008. These fish underwent necropsy so their infracommunities of metazoan parasites could be studied. The same three species of parasites were collected in the two fish species studied. These were one monogenean, one nematode, and one hirudinean. Cucullanus pinnai (Travassos, Artiga, and Pereira, 1928) (Nematoda: Cucullanidae) and Aphanoblastella sp. (Monogenea: Dactylogyridae) were the dominant species with the highest prevalence in P. maculatus and R. quelen. The parasite species of P. maculatus and R. quelen showed an atypical over-dispersed pattern of distribution. No parasite species showed significant correlation between the body total length of the siluriform hosts and their prevalence and abundance. The parasite species richness showed a mean value of 0.87 ± 0.67 (0-2) and 0.57 ± 0.56 (0-2) in P. maculatus and R. quelen, respectively, and no correlation with the body total length. PMID:20943019

  12. [The endoparasitic helminths of Pimelodus maculatus Lacépède, 1803 Siluriformes, Pimelodidae) from the two localities (Lagoon and gutter of the River) of the Guandu River, State of Rio de Janeiro, Brazil].

    PubMed

    Albuquerque, Marcia C; Santos, Michelle D; Monteiro, Cassandra M; Martins, Amanda N; Ederli, Nicole B; Brasil-Sato, Marilia C

    2008-09-01

    Between November 2003 and March 2004, fourty specimens of Pimelodus maculatus Lacépède, 1803 from Guandu River and thirty-nine from Guandu Lagoon (Nova Iguaçu, RJ) were collected, for the analysis of endoparasitic fauna. A total of 236 specimens of Cucullanus pinnai Travassos, Artigas & Pereira, 1928 (Nematoda, Cucullanidae) were collected, being 163 adult specimens in the gut, three in the stomach and 70 larvae in the celomatic cavity and seven specimens of adults Nomimoscolex sp. (Eucestoda, Proteocephalidea) in the gut were found. Cucullanus pinnai presented prevalence (P) 77.50%, mean intensity (MI) 3.40 and mean abundance (MA) 2.60 on River and P: 66.67%, MI: 5.04, MA: 3.36 on Lagoon. Nomimoscolex sp. presented on River P: 2.50%, MI: 2.00, MA: 0.05, and P: 10.26%, MI: 1.25, MA: 0.13 on Lagoon. There was not significant positive interspecific association on the lagoon. In this research, the endoparasitic richness of P. maculatus was scarcest than similar studies in Guandu River and others rivers of different basins. The results about C. pinnai could be suggesting that the cycle of C. pinnai evolve only a host, occurring a histotrophic fase, in this case, in P. maculatus. Periodic analysis of the endoparasites indices in P. maculatus through the years may be used to describe the hydric quality of the Guandu River. PMID:20059829

  13. Identification of Albizia lebbeck seed coat chitin-binding vicilins (7S globulins) with high toxicity to the larvae of the bruchid Callosobruchus maculatus.

    PubMed

    Souza, A J; Ferreira, A T S; Perales, J; Beghini, D G; Fernandes, K V S; Xavier-Filho, J; Venancio, T M; Oliveira, A E A

    2012-02-01

    Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitin-binding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1%, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78%. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation. PMID:22267002

  14. Identification of Albizia lebbeck seed coat chitin-binding vicilins (7S globulins) with high toxicity to the larvae of the bruchid Callosobruchus maculatus

    PubMed Central

    Souza, A.J.; Ferreira, A.T.S.; Perales, J.; Beghini, D.G.; Fernandes, K.V.S.; Xavier-Filho, J.; Venancio, T.M.; Oliveira, A.E.A.

    2011-01-01

    Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitinbinding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1%, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78%. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation. PMID:22267002

  15. Extracellular matrix remodeling of the testes through the male reproductive cycle in Teleostei fish.

    PubMed

    Santana, Julio Cesar de Oliveira; Quagio-Grassiotto, Irani

    2014-12-01

    During the fish reproductive cycle, testes undergo morphological changes related to germinal epithelium and remodeling of extracellular matrix components (ECM). ECM is degraded mainly by action of matrix metalloproteinases (MMPs). Due to the natural renewal of ECM in fish testes, we choose Pimelodus maculatus to study remodeling of ECM throughout reproductive cycle, using picrosirius (to identify type I, II, III collagen) and reticulin (type III collagen), and to immunolocalize MT1-MMP (membrane type 1-matrix metalloproteinase) and MMP-2 in testis cells. Testes were classified in four reproductive phases: regenerating, development, spawning capable and regressing. Picrosirius and reticulin demonstrated a differential distribution of total collagen fibers during the reproductive cycle. Immunohistochemistry showed MT1-MMP only in acidophilic granulocyte cells mainly inside blood vessels, in connective tissue of capsule close to the germinal compartment, and also infiltrated in interstitial connective tissue. MMP-2 was detected in fibroblast and endothelial cells of interstitial and capsule blood vessels, in epithelial cells of capsule, and in acidophilic granulocyte cells at same description for MT1-MMP. The fish testes ECM were remodeled throughout reproductive cycle in according to morphophysiological alterations. During reproductive season (spawning capable), the interstitium increased in total collagen fibers (type I, II, III). After spermiation period (regression and regenerating), the amount of collagen fibers decreased in response to action of MMPs on collagen degradation and other interstitial components (not assessed in this study). MMPs seem to be indispensable components for natural cyclic events of ECM remodeling of fish testes and for guarantee tissue homeostasis throughout reproductive cycle. PMID:25142725

  16. Molecular taxonomy and identification within the Antarctic genus Trematomus (Notothenioidei, Teleostei): How valuable is barcoding with COI?

    NASA Astrophysics Data System (ADS)

    Lautredou, A.-C.; Bonillo, C.; Denys, G.; Cruaud, C.; Ozouf-Costaz, C.; Lecointre, G.; Dettai, A.

    2010-08-01

    The Trematominae are a particularly interesting subfamily within the antarctic suborder Notothenioidei (Teleostei). The 14 closely related species occupy a large range of ecological of niches, extremely useful for evolutionary and biogeography studies in the Antarctic Ocean. But some Trematomus species can be difficult to identify by using morphological criteria, specially young stages and damaged specimens. Molecular identification would therefore be highly useful, however the suitability of the cytochrome oxidase I gene in a barcoding approach needs to be assessed. We evaluated species delineation within the genus Trematomus comparing morphological identification, nuclear markers (the rhodopsin retrogene and a new nuclear marker pkd1: polycystic kidney disease 1) and COI. We show that Trematomus vicarius is not distinguishable from Trematomus bernacchii with the molecular markers used, and neither is Trematomus loennbergii from Trematomus lepidorhinus. We suggest that until this is investigated further, studies including these species list them as T. loennbergii/ T. lepidorhinus group, and keep voucher samples and specimens. Generally, COI gives a congruent result with the rhodopsin retrogene, and except for the previously cited species pairs, COI barcoding is efficient for identification in this group. Moreover pkd1 might not be suitable for a phylogenetic study at this scale for this group.

  17. Effects of Enteromyxum leei (Myxozoa) infection on gilthead sea bream (Sparus aurata) (Teleostei) intestinal mucus: glycoprotein profile and bacterial adhesion.

    PubMed

    Estensoro, Itziar; Jung-Schroers, Verena; Álvarez-Pellitero, Pilar; Steinhagen, Dieter; Sitjà-Bobadilla, Ariadna

    2013-02-01

    The intestinal myxosporean parasite Enteromyxum leei causes severe desquamative enteritis in gilthead sea bream (Sparus aurata) (Teleostei) that impairs nutrient absorption causing anorexia and cachexia. In fish, as in terrestrial vertebrates, intestinal goblet cells are responsible for the adherent mucus secretion overlying epithelial cells, which constitutes a first line of innate immune defense against offending microorganisms but serves also as substrate and nutrient source for the commensal microflora. The secreted intestinal mucus of parasitized (n = 6) and unexposed (n = 8) gilthead sea bream was isolated, concentrated, and subjected to downward gel chromatography. Carbohydrate and protein contents (via PAS and Bradford stainings), terminal glycosylation (via lectin ELISA), and Aeromonas hydrophila and Vibrio alginolyticus adhesion were analyzed for the isolated intestinal mucins. Parasitized fish, compared with unexposed fish, presented intestinal mucus mucins with a lower glycoprotein content and glycosylation degree at the anterior and middle intestine, whereas both glycoprotein content and glycosylation degree increased at the posterior intestine section, though only significantly for the total carbohydrate content. Additionally, a slight molecular size increase was detected in the mucin glycoproteins of parasitized fish. Terminal glycosylation of the mucus glycoproteins in parasitized fish pointed to an immature mucin secretion (N-acetyl-α-D-galactosamine increase, α-L-fucose, and neuraminic-acid-α-2-6-galactose reduction). Bacterial adhesion to large-sized mucus glycoproteins (>2,000 kDa) of parasitized fish was significantly lower than in unexposed fish. PMID:23086443

  18. A new variant of antimetabolic protein, arcelin from an Indian bean, Lablab purpureus (Linn.) and its effect on the stored product pest, Callosobruchus maculatus.

    PubMed

    Janarthanan, Sundaram; Sakthivelkumar, Shanmugavel; Veeramani, Velayutham; Radhika, Dixit; Muthukrishanan, Subbaratnam

    2012-12-15

    The anti-metabolic or insecticidal gene, arcelin (Arl) was isolated, cloned and sequenced using sequence specific degenerate primers from the seeds of Lablab purpureus collected from the Western Ghats, Tamil Nadu, India. The L. purpureus arcelin nucleotide sequence was homologous to Arl-3 and Arl-4 alleles from Phaseolus spp. The protein it encodes has 70% amino acid identity with the amino acid sequences of Arl-3I, Arl-3III, Arl-4 precursor, Arl-4 and Arl-4I. The partially purified arcelin from the seeds of L. purpureus using an artificial diet confirmed the complete retardation of development of the stored product pest Callosobruchus maculatus at 0.2% w/w arcelin-incorporated artificial seeds. PMID:22980880

  19. Structural chromosome polymorphism in a Pimelodus maculatus La Cepède, 1803 population (Siluriformes, Pimelodidae) from the Paranapanema River basin, PR, Brazil.

    PubMed

    Mazzuchelli, J; Swarça, A C; Dias, A L

    2007-12-01

    In the present cytogenetic study of Pimelodus maculatus, 13 specimens (8 males and 5 females) from the Congonhas Stream in Paraná State, Brazil, were examined using conventional staining. All of them showed a karyotype of 2n=56, with a chromosome distribution of 20m + 20sm + 10st + 6a. However, four individuals (2 males and 2 females) were found to have a variant karyotype (cytotype) with two heteromorphic chromosomes in the group of submetacentric chromosomes--one of them corresponds to the second largest chromosome of this group and the other is a chromosome of small size. This variation suggests the existence of a structural polymorphism in the studied population. PMID:18278362

  20. Neotropical monogenoidea. 55. Dactylogyrids parasitising the pintado-amarelo Pimelodus maculatus Lacépède (Actinopterygii: Pimelodidae) from the Rio São Francisco, Brazil.

    PubMed

    Monteiro, Cassandra M; Kritsky, Delane C; Brasil-Sato, Marilia C

    2010-07-01

    Eight species of Dactylogyridae were collected from the gills of the pintado-amarelo Pimelodus maculatus Lacépède in the Rio São Francisco in Brazil: Ameloblastella paranaensis (França, Isaac, Pavanelli & Takemoto, 2003) Mendoza-Franco & Scholz, 2009, A. satoi n. sp., Ameloblastella sp., Demidospermus armostus Kritsky & Gutiérrez, 1998, D. cf. bidiverticulatum (Suriano & Incorvaia, 1995) Kritsky & Gutiérrez, 1998, D. ichthyocercus n. sp., D. paravalenciennesi Gutiérrez & Suriano, 1992 and D. uncusvalidus Gutiérrez & Suriano, 1992. Two new species, A. satoi n. sp. and D. ichthyocercus n. sp., are described, and A. paranaensis is redescribed. The Rio São Francisco represents new geographical records for the five previously described dactylogyrid species. PMID:20532849

  1. Cytomorphological alterations of the thymus, spleen, head-kidney, and liver in cardinal fish (Apogonidae, Teleostei) as bioindicators of stress.

    PubMed

    Fishelson, Lev

    2006-01-01

    Morphological and cytological alterations at the light microscope (LM) and transmission electron microscope (TEM) levels were observed in the thymus, spleen, head-kidney, and liver of cardinal fishes (Apogonidae, Teleostei) from the Gulf of Aqaba, Red Sea, sampled from a strongly polluted site at the northern end of the gulf, and compared to similar samples from a clean, reference site. At the polluted site, the most prominent change was the formation of numerous deposits of cells rich in phagosomes with lipofucin, melanin granules, and phagocytosed debris, including a high increase in number and dimensions of Hassall's corpuscles and melano-macrophage centers. The number of Hassall's corpuscles was 20 (+/-8.0)/mm(2) and of melano-macrophage centers 18 (+/-4.0)/mm(2) at the polluted site, and 7.0 (+/-4.0)/m(2) vs. 5.0 (+/-2.0)/mm(2) respectively at the reference site. In numerous instances the head kidney's melano-macrophage centers in fishes from the polluted site were encapsulated by reticulocytes, a phenomenon recognized as a marker of neoplasmosis and possible malignancy. In the spleens of fishes from the polluted site, numerous deposits of cell debris, peroxisomes, and enlarged lysosomes were also observed. The livers (hepatopancreas) of fishes from polluted waters demonstrated very strong hyperlipogeny. Many of their hepatocytes were laden with lipid vesicles, fragmented endoplasmic reticulula, and aberrant mitochondria. Although the observed alterations in the glands and liver do not indicate any immediate threat to the life of the fish, they can become crucial with respect to energy turnover and fecundity trajectories. This study strongly suggests the use of cytological alterations in vital organs, such as were observed, as pathological biomarkers to environmental stress. PMID:16247768

  2. 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 Late Cretaceous to form the present-day distribution of organisms. Furthermore, the Late Cretaceous biotic turnover influenced for the modern terrestrial biodiversity. PMID:23174367

  3. A review of Galaxiella pusilla (Mack) (Teleostei: Galaxiidae) in south-eastern Australia with a description of a new species.

    PubMed

    Coleman, Rhys A; Hoffmann, Ary A; Raadik, Tarmo A

    2015-01-01

    The dwarf galaxias, Galaxiella pusilla (Mack), is a small, threatened freshwater fish from coastal south-eastern Australia. Recent genetic studies, using multiple nuclear and mitochondrial DNA markers, found substantial differences between populations in western Victoria and south Australia ('west region') compared to eastern Victoria, Flinders Island, and Tasmania ('east region') that suggest the presence of a cryptic species. Morphological measurements and meristic counts from multiple populations within each region were undertaken to investigate potential differences between regions. Several characters, found to discriminate between individuals in the regions and to be diagnostic for two taxa, were used to describe a new species, Galaxiella toourtkoourt, for the west region. This is only the second species in the Galaxiidae to exhibit sexual dimorphism. The original description of Galaxiella pusilla, based on five specimens, is revised following examination of a large number of individuals. Both species are considered nationally threatened and are categorised as 'endangered'; the revised distribution of G. pusilla s.s. is reduced by approximately 60%. A number of inconsistencies in the most recent revision of the genus Galaxiella are also corrected. PMID:26624129

  4. 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). PMID:25796547

  5. Calicobenedenia Polyprioni n. gen., n. sp. (Monogenoidea: Capsalidae) from the external surfaces of wreckfish, Polyprion americanus (Teleostei: Polyprionidae), in the north Atlantic.

    PubMed

    Kritsky, D C; Fennessy, C J

    1999-04-01

    Calicobenedenia polyprioni n. sp. (Capsalidae) is described from the external surfaces (skin and eye) of wreckfish, Polyprion americanus (Teleostei, Perciformes, Polyprionidae), from the north Atlantic Ocean. The monotypic Calicobenedenia n. gen. is proposed for this species and is characterized, in part, by its members possessing an aseptate haptor armed with 14 submarginal hooks and 1 pair of anchors, a common genital pore opening marginally immediately posterior to the left cephalic lobe, 2 testes juxtaposed near the body midlength, and by lacking cephalic suckers or adhesive discs, accessory haptoral sclerites, and a uterine valve. The new genus most closely resembles Entobdella, which differs from Calicobenedenia by having an aseptate haptor armed with 14 submarginal hooks, 2 pairs of anchors, and a pair of accessary sclerites. PMID:10219294

  6. Next-generation sequencing yields the complete mitochondrial genome of the flathead mullet, Mugil cephalus cryptic species in East Australia (Teleostei: Mugilidae).

    PubMed

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

    2016-09-01

    In this study, the complete mitogenome sequence of a cryptic species from East Australia (Mugil sp. H) belonging to the worldwide Mugil cephalus species complex (Teleostei: Mugilidae) has been sequenced by next-generation sequencing method. The assembled mitogenome, consisting of 16,845 bp, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes and a non-coding control region of D-loop. D-loop consists of 1067 bp length, and is located between tRNA-Pro and tRNA-Phe. The overall base composition of East Australia M. cephalus is 28.4% for A, 29.3% for C, 15.4% for G and 26.9% for T. The complete mitogenome may provide essential and important DNA molecular data for further phylogenetic and evolutionary analysis for flathead mullet species complex. PMID:25693715

  7. A new gonad-infecting species of Philometra (Nematoda: Philometridae) from the Atlantic Spanish mackerel Scomberomorus maculatus (Scombridae) off the Atlantic Coast of Florida and South Carolina.

    PubMed

    Moravec, František; Bakenhaster, Micah; de Buron, Isaure

    2013-04-01

    A new nematode species, Philometra atlantica n. sp. (Philometridae), is described from male and female specimens found in the ovary of the Atlantic Spanish mackerel, Scomberomorus maculatus (Mitchill) (Scombridae, Perciformes), off the Atlantic coast of Florida and South Carolina. Based on light and scanning electron microscopy examination, the new species differs from most other gonad-infecting Philometra spp. in the length of spicules (111-126 μm), number and arrangement of genital papillae, and a U-shaped, dorsally interrupted caudal mound in the male. A unique feature among all gonad-infecting philometrids is the presence of 2 reflexed dorsal barbs on the distal end of the gubernaculum. From a few congeneric, gonad-infecting species with unknown males, it can be distinguished by some morphological and biometrical features found in gravid females (body length, length of first-stage larvae or esophagus, structure of caudal end) and by the host type (fish family) and geographical distribution. Philometra atlantica is the fourth valid gonad-infecting species of Philometra reported from fishes of the family Scombridae. PMID:23066819

  8. Comparative morphology of the gonadal structure related to reproductive strategies in six species of neotropical catfishes (Teleostei: Siluriformes).

    PubMed

    Melo, Rafael Magno Costa; Arantes, Fábio Pereira; Sato, Yoshimi; dos Santos, José Enemir; Rizzo, Elizete; Bazzoli, Nilo

    2011-05-01

    We studied the relationship between the morphology of the reproductive system and the reproductive strategies of six neotropical catfishes using macroscopic and microscopic analyses. The reproductive system of the examined Siluriformes showed diversified characteristics, but permitted their being grouped according to three reproductive strategies: pelagic spawning, demersal spawning, and internally fertilizing. The pelagic spawners Pseudoplatystoma corruscans and Conorhynchos conirostris have testes that are characterized by filiform lobes, absence of testicular secretion, full-grown oocytes of small diameter, thin zona radiata, and cuboidal follicular cells. Pimelodus maculatus is morphologically distinct from the other two pelagic spawners catfishes due to the presence of testicular secretion. The demersal spawners Lophiosilurus alexandri and Rhinelepis aspera possess homogeneous testicular secretion, large mature oocytes, and columnar follicular cells. The most specialized reproductive system was observed in the internally fertilizing Trachelyopterus galeatus, which possesses a seminal vesicle accessory to the testes, spermatozoa with elongated nuclei that form spermatozeugmata, and a secretory ovarian lamellar epithelium that is associated with sperm storage. The reproductive system observed in Neotropical catfishes showed a relationship associated with the type of fertilization and the reproductive strategies of the six species studied. PMID:21246599

  9. Insecticide activity of essential oils of Mentha longifolia, Pulicaria gnaphalodes and Achillea wilhelmsii against two stored product pests, the flour beetle, Tribolium castaneum, and the cowpea weevil, Callosobruchus maculatus.

    PubMed

    Khani, Abbas; Asghari, Javad

    2012-01-01

    Essential oils extracted from the foliage of Mentha longifolia (L.) (Lamiales: Lamiaceae) and Pulicaria gnaphalodes Ventenat (Asterales: Asteraceae), and flowers of Achillea wilhelmsii C. Koch (Asterales: Asteraceae) were tested in the laboratory for volatile toxicity against two storedproduct insects, the flour beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) and the cowpea weevil, Callosobruchus maculatus F. (Coleoptera: Bruchidae). The chemical composition of the isolated oils was examined by gas chromatography-mass spectrometry. InM longifolia, the major compounds were piperitenon (43.9%), tripal (14.3%), oxathiane (9.3%), piperiton oxide (5.9%), and d-limonene (4.3%). In P. gnaphalodes, the major compounds were chrysanthenyl acetate (22.38%), 2L -4L-dihydroxy eicosane (18.5%), verbenol (16.59%), dehydroaromadendrene (12.54%), β-pinen (6.43%), and 1,8 cineol (5.6%). In A. wilhelmsii, the major compounds were 1,8 cineole (13.03%), caranol (8.26%), alpha pinene (6%), farnesyl acetate (6%), and p-cymene (6%). C maculatus was more susceptible to the tested plant products than T castaneum. The oils of the three plants displayed the same insecticidal activity against C. maculatus based on LC(50) values (between 1.54µl/L air in P. gnaphalodes, and 2.65 µl/L air in A. wilhelmsii). While the oils of A. wilhelmsii and M. longifolia showed the same strong insecticidal activity against T. castaneum (LC(50) = 10.02 and 13.05 µl/L air, respectively), the oil of P. gnaphalodes revealed poor activity against the insect (LC(50) = 297.9 µl/L air). These results suggested that essential oils from the tested plants could be used as potential control agents for stored-product insects. PMID:23413994

  10. Growth and reproduction aspects of Pimelodus maculatus Lacépède, 1803 (Siluriformes, Pimelodidae) of the Cachoeira Dourada reservoir, state of Goiás and Minas Gerais, Brazil.

    PubMed

    Sabinson, L M; Rodrigues Filho, J L; Peret, A C; Verani, J R

    2014-05-01

    Growth and reproduction parameters of the yellow-mandi, Pimelodus maculatus Lacépède, 1803 (Siluriformes, Pimelodidae), were determined for the Cachoeira Dourada reservoir (GO/MG). The field work occurred throughout February 2007 to January 2008 (with the exception of December 2007). Gill nets with mesh sizes from 1.5 to 10 centimeters were placed in three different areas in the reservoir and were collected 24 hours later. A total of 538 specimens were captured, amongst which 242 were females, 219 were males and 77 could not have their sex determined. Sex ratio differed from 1:1 only during July 2007 and January 2008, with males and females predominating in each of those months. Males occupied the medium length classes (18.9 to 24.3 cm) while females were most abundant in the superior classes (from 27 to 37.8 cm).The growth constant K was statistically equal for males (K=0.1851) and females (K=0.1708), however, females P. maculatus may have a greater investment in reproductive tissue, a fact indicated by the elevated values of Kn and GSI during the summer. Bearing in mind that P. maculatus reproduces in the rainy season, a greater gain in weight is expected during the months before the reproduction season, and that after it occurs the fish loses fat and weight as a consequence of metabolic effort. Still, the absence of juveniles may be an indication that the species did not find in the reservoir the proper conditions for reproduction and growth of its fry. PMID:25166330

  11. Insecticide Activity of Essential Oils of Mentha longifolia, Pulicaria gnaphalodes and Achillea wilhelmsii Against Two Stored Product Pests, the Flour Beetle, Tribolium castaneum, and the Cowpea Weevil, Callosobruchus maculatus

    PubMed Central

    Khani, Abbas; Asghari, Javad

    2012-01-01

    Essential oils extracted from the foliage of Mentha longifolia (L.) (Lamiales: Lamiaceae) and Pulicaria gnaphalodes Ventenat (Asterales: Asteraceae), and flowers of Achillea wilhelmsii C. Koch (Asterales: Asteraceae) were tested in the laboratory for volatile toxicity against two storedproduct insects, the flour beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) and the cowpea weevil, Callosobruchus maculatus F. (Coleoptera: Bruchidae). The chemical composition of the isolated oils was examined by gas chromatography-mass spectrometry. InM longifolia, the major compounds were piperitenon (43.9%), tripal (14.3%), oxathiane (9.3%), piperiton oxide (5.9%), and d-limonene (4.3%). In P. gnaphalodes, the major compounds were chrysanthenyl acetate (22.38%), 2L -4L-dihydroxy eicosane (18.5%), verbenol (16.59%), dehydroaromadendrene (12.54%), β-pinen (6.43%), and 1,8 cineol (5.6%). In A. wilhelmsii, the major compounds were 1,8 cineole (13.03%), caranol (8.26%), alpha pinene (6%), farnesyl acetate (6%), and p-cymene (6%). C maculatus was more susceptible to the tested plant products than T castaneum. The oils of the three plants displayed the same insecticidal activity against C. maculatus based on LC50 values (between 1.54µl/L air in P. gnaphalodes, and 2.65 µl/L air in A. wilhelmsii). While the oils of A. wilhelmsii and M. longifolia showed the same strong insecticidal activity against T. castaneum (LC50 = 10.02 and 13.05 µl/L air, respectively), the oil of P. gnaphalodes revealed poor activity against the insect (LC50 = 297.9 µl/L air). These results suggested that essential oils from the tested plants could be used as potential control agents for stored-product insects. PMID:23413994

  12. Effects of insecticide formulations used in cotton cultivation in West Africa on the development of flat-backed toad tadpoles (Amietophrynus maculatus).

    PubMed

    Stechert, Christin; Kolb, Marit; Rödel, Mark-Oliver; Bahadir, Müfit

    2015-02-01

    In the West African savanna zone, traditional subsistence farming increasingly shifts to cash crop farming and in particular to cotton cultivation, which is accompanied by application of pesticides. Increasing use of pesticides by smallholder farmers is suspected to have negative effects on non-target organisms. In this study, possible pesticide impact on the development of tadpoles was investigated. Two insecticide formulations used in cotton cultivation in Benin were compared: Cotofan® (active ingredient (a.i.): α- and β-endosulfan) and Tihan® (a.i.: spirotetramat and flubendiamide). Tadpoles of the widespread species Amietophrynus maculatus were kept in small water basins with increasing insecticide concentrations (1, 10 and 100 μg a.i./L) over a period of 28 days. Tadpoles showed reduced survival at the highest endosulfan concentrations (100 μg/L). Survival of tadpoles undergoing metamorphosis was not influenced by Tihan®. Endosulfan in concentrations of 10 and 100 μg/L negatively impacted the movement of the tadpoles which was not the case for the mixture of spirotetramat and flubendiamide. Time to metamorphosis was not significantly different in the various treatments. Tail length of tadpoles was significantly shorter in Cotofan® treatments compared to controls. Pesticide residues in the tadpoles were relatively low after keeping them in concentrations of 1 and 10 μg a.i./L (25 and 26 μg/kg wet weight (w/w) for the sum of α-endosulfan, β-endosulfan and endosulfan sulphate and below the detection limits for flubendiamide and spirotetramat). For the 100 μg a.i./L treatments, 1,600 μg/kg w/w was found of α-endosulfan, β-endosulfan and endosulfan sulphate together in the survived tadpoles and 21 μg/kg w/w of flubendiamide. PMID:25192667

  13. Protecting embryos from stress: Corticosterone effects and the corticosterone response to capture and confinement during pregnancy in a live-bearing lizard (Hoplodactylus maculatus)

    USGS Publications Warehouse

    Cree, A.; Tyrrell, C.L.; Preest, M.R.; Thorburn, D.; Guillette, L.J., Jr.

    2003-01-01

    Hormones in the embryonic environment, including those of the hypothalamo-pituitary-adrenal (HPA) axis, have profound effects on development in eutherian mammals. However, little is known about their effects in reptiles that have independently evolved viviparity. We investigated whether exogenous corticosterone affected embryonic development in the viviparous gecko Hoplodactylus maculatus, and whether pregnant geckos have a corticosterone response to capture and confinement that is suppressed relative to that in non-pregnant (vitellogenic) females and males. Corticosterone implants (5 mg, slow-release) administered to females in mid-pregnancy caused a large elevation of corticosterone in maternal plasma (P<0.001), probable reductions in embryonic growth and development (P=0.069-0.073), developmental abnormalities and eventual abortions. Cool temperature produced similar reductions in embryonic growth and development (P???0.036 cf. warm controls), but pregnancies were eventually successful. Despite the potentially harmful effects of elevated plasma corticosterone, pregnant females did not suppress their corticosterone response to capture and confinement relative to vitellogenic females, and both groups of females had higher responses than males. Future research should address whether lower maternal doses of corticosterone produce non-lethal effects on development that could contribute to phenotypic plasticity. Corticosterone implants also led to increased basking in pregnant females (P<0.001), and basal corticosterone in wild geckos (independent of reproductive condition) was positively correlated with body temperature (P<0.001). Interactions between temperature and corticosterone may have broad significance to other terrestrial ectotherms, and body temperature should be considered as a variable influencing plasma corticosterone concentrations in all future studies on reptiles. ?? 2003 Elsevier Inc. All rights reserved.

  14. The attraction of virgin female hide beetles (Dermestes maculatus) to cadavers by a combination of decomposition odour and male sex pheromones

    PubMed Central

    2012-01-01

    Introduction The hide beetle Dermestes maculatus (Coleoptera: Dermestidae) feeds as an adult and larva on decomposing animal remains and can also be found on human corpses. Therefore, forensic entomological questions with regard to when and how the first receptive females appear on carcasses are important, as the developmental stages of their larvae can be used to calculate the post-mortem interval. To date, we know that freshly emerged males respond to the cadaver odour of post-bloated carcasses (approximately 9 days after death at Tmean = 27°C), being attracted by benzyl butyrate. This component occurs at its highest concentration at this stage of decay. The aim of our study was to determine the principle of attraction of virgin females to the feeding and breeding substrate. For this purpose, we tested the response of these females to headspace samples of piglet cadavers and male sex pheromones [(Z9)-unsaturated fatty acid isopropyl esters] in a Y-olfactometer. Because we expected that such an odour combination is of importance for virgin female attraction, we tested the following two questions: 1) Are virgin female hide beetles attracted by a combination of cadaver odour and male sex pheromones? 2) During which decomposition stage do the first virgin females respond to cadaver odour when combined with male sex pheromones? Results We found that young virgin females were attracted to the cadaver by a combination of cadaver odour and male sex pheromones. Neither cadaver odour alone nor male sex pheromones alone was significantly more attractive than a solvent control. Our results also gave a weak indication that the first young virgin females respond as early as the post-bloating stage to its associated decomposition odour when combined with male sex pheromones. Conclusions Our results indicate that freshly emerged males possibly respond to cadaver odour and visit carcasses before virgin females. Being attracted to cadavers when male sex pheromone is perceived as well, virgin females can optimise their reproductive possibilities. PMID:22889339

  15. Performance of bean bruchids Callosobruchus maculatus and Zabrotes subfasciatus (Coleoptera: Bruchidae) reared on resistant (IT81D-1045) and susceptible (Epace 10) Vigna unguiculata seeds: relationship with trypsin inhibitor and vicilin excretion.

    PubMed

    Sales, M P; Andrade, L B S; Ary, M B; Miranda, M R A; Teixeira, F M; Oliveira, A S; Fernandes, K V S; Xavier-Filho, J

    2005-12-01

    Callosobruchus maculatus (Cm) and Zabrotes subfasciatus (Zs) were reared on resistant (IT81D-1045) and on susceptible (Epace 10) cowpea seeds. The emergence of adult insects, total developmental period (TDP) and excretion of trypsin inhibitor and vicilin were determined for both bruchid populations. Parameter evaluation showed that the Zs populations emerged from both seeds had no significant differences in emergence and TDP. The Cm population raised from resistant seeds had lower emergence (5.6+/-1.3%) and delayed TDP (46+/-1.25 days) than those emerged from susceptible seeds. The excretion of defense proteins showed that Zs reared in resistant seeds excreted 1.7 times more trypsin inhibitor, but this did not affect emergence or TDP. Furthermore, Cm population emerged from resistant seeds excreted 7 times higher vicilin and 0.4 times less trypsin inhibitor than that emerged from susceptible seeds. These results indicate that vicilins from resistant seeds are involved to significantly longer TDP (46 days) and also drastic reduction of insect emergence ( approximately 5%) of C. maculatus. PMID:16246611

  16. 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

  17. Ubiquity of Sicyopterus lagocephalus (Teleostei: Gobioidei) and phylogeography of the genus Sicyopterus in the Indo-Pacific area inferred from mitochondrial cytochrome b gene.

    PubMed

    Keith, P; Galewski, T; Cattaneo-Berrebi, G; Hoareau, T; Berrebi, P

    2005-12-01

    Sicyopterus lagocephalus is a Gobiidae Sicydiinae (Teleostei) thought to inhabit Indo-Pacific island rivers from Comoros Islands in the Indian Ocean to Australs Islands (French Polynesia) in the Pacific Ocean. Its biological cycle comprises a marine planctonic larval phase of several months allowing it to migrate from island to island, but the other species of the genus, with such a larval stage, have generally a more restricted range and are often endemic. To understand the organisation of a species with such a wide distribution, mtDNA cytochrome b sequences were amplified for 55 specimens of this genus covering most of its distribution range together with six close endemic species and other gobiids used as outgroups. The main result is the confirmation of the ubiquity of S. lagocephalus that occurs over a range of 18,000 km in the Indian and Pacific Oceans. Two clades were identified within this species, one clustering most of French Polynesian haplotypes and the other clustering most of Mascarene (including Comoros) haplotypes. The overall pattern of distribution and phylogenetic relationship suggests that the lineages leading to endemic species originated earlier than S. lagocephalus. This latter seems to be a secondary migrant species, having colonised both Indian and Pacific Oceans with a few exceptions, situated at the border of the range (Madagascar, Marquesas, Rapa). According to the results, the phylogeny of the Sicyopterus group, the age of the different lineages and the past history of the colonisation of the Indo-Pacific islands are discussed. PMID:16214374

  18. Naricolax hoi n. sp. (Cyclopoida: Bomolochidae) from Arius maculatus (Siluriformes: Ariidae) off Taiwan and a redescription of N. chrysophryenus (Roubal, Armitage & Rohde, 1983) from a new host, Seriola lalandi (Perciformes: Carangidae), in Australian waters.

    PubMed

    Hutson, Kate S; Tang, Danny

    2007-10-01

    We propose that Naricolax stocki (Roubal, 1981) (Cyclopoida: Bomolochidae) of Ho & Lin (2005), reported from the spotted catfish Arius maculatus (Thunburg) off Taiwan, represents a new species, N. hoi n. sp. N. hoi can be distinguished from six known congeners by the shape of the rostral area, the maxillary armature and the structural details of legs 3 and 4. N. chrysophryenus (Roubal, Armitage & Rohde, 1983) is redescribed on the basis of recently collected material from wild and farmed yellowtail kingfish Seriola lalandi Valenciennes in southern and eastern Australian waters, providing the first record of Naricolax Ho, Do & Kasahara, 1983 from a carangid host. A key to the species of Naricolax is provided. PMID:17912616

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

    PubMed

    Lavou, Sbastien; 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. PMID:15324846

  20. 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; Prez-Ponce de Len, Gerardo; Rubio-Godoy, Miguel

    2013-12-01

    Phyllodistomum inecoli n. sp. is described from the twospot livebearer, Heterandria bimaculata (Teleostei: Poeciliidae), collected in the Ro 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 1,5002,200 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. PMID:24022129

  1. The basement membrane and the sex establishment in the juvenile hermaphroditism during gonadal differentiation of the Gymnocorymbus ternetzi (Teleostei: Characiformes: Characidae).

    PubMed

    Mazzoni, Talita Sarah; Grier, Harry J; Quagio-Grassiotto, Irani

    2015-12-01

    Although there are several studies on morphogenesis in Teleostei, until now there is no research describing the role of the basement membrane in the establishment of the germinal epithelium during gonadal differentiation in Characiformes. In attempt to study these events that result in the formation of ovarian and testicular structures, gonads of Gymnocorymbus ternetzi were prepared for light microscopy. During gonadal development in G. ternetzi, all individuals first developed ovarian tissue. The undifferentiated gonad was formed by somatic cells (SC) and primordial germ cells (PGCs). After successive mitosis, the PGCs became oogonia, which entered into meiosis originating oocytes. An interstitial tissue developed. In half of the individuals, presumptive female, prefollicle cells synthesized a basement membrane around oocyte forming a follicle. Along the ventral region of the ovary, the tissue invaginated to form the ovigerous lamellae, bordered by the germinal epithelium. Stroma developed and the follicle complexes were formed. The gonadal aromatase was detected in interstitial cells in the early steps of the gonadal differentiation in both sexes. In another half of the individuals, presumptive male, there was no synthesis of basement membrane. The interstitium was invaded by numerous granulocytes. Pre-Leydig cells proliferated. Apoptotic oocytes were observed and afterward degenerated. Spermatogonia appeared near the degenerating oocytes and associated to SCs, forming testicular tubules. Germinal epithelium developed and the basement membrane was synthesized. Concomitantly, there was decrease of the gonadal aromatase and increase in the 3β-HSD enzyme expression. Thus, the testis was organized on an ovary previously developed, constituting an indirect gonochoristic differentiation. PMID:26386207

  2. 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. PMID:25174849

  3. Scale surface microstructure and scale size in the tooth-carp genus Aphanius (Teleostei, Cyprinodontidae) from endorheic basins in Southwest Iran.

    PubMed

    Gholami, Zeinab; Teimori, Azad; Esmaeili, Hamid Reza; Schulz-Mirbach, Tanja; Reichenbacher, Bettina

    2013-01-01

    A substantial number of species within the tooth-carp Aphanius Nardo, 1827 (Cyprinodontidae, Teleostei) has been recorded from the endorheic drainage systems of Iran, and several isolated populations in these systems may deserve species status. Descriptions of these species and populations have been based mainly on morphological and molecular data; however, the characters related to the fish scales have not up to now been intensively studied and employed for the identification of the species belonging to this genus. The objective of this study is to test as to whether (i) scale surface morphology, (ii) scale surface microstructure, and (iii) scale size can be used to discriminate species and/or populations and, (iv) to discuss the possible causes of the observed differences. To achieve these objectives, scales of three species of the genus Aphanius from endorheic basins in SW Iran, viz. A. sophiae (nine populations from the Kor River Basin), A. farsicus (four populations from the Maharlu Lake Basin) and A. pluristriatus (a single population from the Mond River Basin) have been studied using SEM images, scale measurements, and uni- and multivariate statistics. It is opined that scale surface morphology and microstructure cannot help in distinguishing the species, but can be employed to discriminate certain populations of A. sophiae (those from Safashahr, Kharameh, Tashk, Gol). In addition, scale size and J-indices, respectively, represent a valuable tool for species separation, which corroborates earlier studies for the use of these indices in taxonomy. Major driving forces of the differentiation within A. sophiae probably include habitat fragmentation resulting from the geological history and local adaptations. Thus the differentiation results from a balance between both genetic and environmental effects. PMID:26131487

  4. Unique features of pedicellate attachment of the upper jaw teeth in the adult gobiid fish Sicyopterus japonicus (Teleostei, Gobiidiae): morphological and structural characteristics and development.

    PubMed

    Sahara, Noriyuki; Moriyama, Keita; Iida, Midori; Watanabe, Shun

    2013-05-01

    Sicyopterus japonicus (Teleostei, Gobiidae), a hill-stream herbivorous gobiid fish, possesses an unusual oral dentition among teleost fishes on account of its feeding habitat. By using scanning electron microscopy, light microscopy, and transmission electron microscopy, including vital staining with tetracycline, we examined the development of the attachment tissues of the upper jaw teeth in this fish. The functional teeth of S. japonicus had an asymmetrical dentine shaft. The dentine shaft attached to the underlying uniquely shaped pedicel by means of two different attachment mechanisms. At the lingual base, collagen fiber bundles connected the dentine shaft with the pedicel (hinged attachment), whereas the labial base articulated with an oval-shaped projection of the pedicel (articulate attachment). The pedicel bases were firmly ankylosed to the crest of the thin flange of porous spongy bone on the premaxillary bone, which afforded a flange-groove system on the labial surface of the premaxillary bone. Developmentally, the pedicel and thin flange of spongy bone were completely different mineralized attachment tissues. The pedicel had a dual origin, i.e., the dental papilla cells, which differentiated into odontoblasts that constructed the internal surface of the pedicel, and the mesenchymal cells, which differentiated into osteoblasts that formed the outer face of the pedicel. A thin flange of spongy bone was deposited on the superficial resorbed labial side of the premaxillary bone proper, and later rapid bone remodeling proceeded toward the pedicel base. These unique features of pedicellate tooth attachment for the upper jaw teeth in the adult S. japonicus are highly modified teeth for enhancing the ability of individual functional teeth to move closely over irregularities in the rock surfaces during the scraping of algae. PMID:23280699

  5. 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 and temperatures shows its potential to readily adapt to several environmental conditions. These findings, together with the fact that A. fasciatus is a protected species and is considered as a biological control organism, necessitate further studies on the ecology and virulence of G. salinae n. sp. PMID:21658217

  6. Simulaciones de formacin de galaxias disco barreadas

    NASA Astrophysics Data System (ADS)

    Algorry, D. G.; Abadi, M. G.; Ferrero, I.

    2015-08-01

    In this work we present a study of the formation and evolution of two galaxies selected from a series of numerical cosmological hydrodynamical simulations called GIMIC. The first one is a galaxy with a central bar at redshift z = 0 formed between 9 t [Gyr] 11. At this time, the galaxy accretes gas from distinct directions forming a ring located in a different plane respect to the galaxy disc. This disc transfers its angular momentum to the gas and halo decaying its pattern speed and becoming a bar. The second one is a galaxy that had a bar until a time t 10 Gyr. After this time, the bar gradually disintegrate until redshift z = 0 (t = 13.6 Gyr). This disintegration is unusual and may be due to strong perturbations originated by the proximity of a massive satellite at t 10 Gyr.

  7. Las Galaxias Enanas y la Red Csmica

    NASA Astrophysics Data System (ADS)

    Bentez Llambay, A.; Abadi, M. G.

    Using a cosmological numerical simulation of the Local Group formation, we identify a mechanism able to remove gas from low-mass halos, affecting dramatically their star formation histories. As the Local Group forms, matter bound to it develops an intrincate network of filaments and pancakes, which sweeps a large volume, overtaking and removing the gas of several halos, leaving their dark matter component unaffected. The gas loss is particulary pronunced for low-mass halos, which may help to explain the scarcity of dwarf galaxies observed when compared to the large number of low-mass halos expected in the ?CDM cosmological model. FULL TEXT IN SPANISH

  8. Interacciones de galaxias: sistemas con puentes tidales

    NASA Astrophysics Data System (ADS)

    Mesa, V.; Alonso, S.; Duplancic, F.; Lambas, D. G.

    2015-08-01

    In this work we present a sample of interacting galaxy pairs connected by a bridge, obtained from a visual classification of a pair catalogue derived from the seventh data release of the Sloan Digital Sky Survey (SDSS-DR7). We present preliminary results of the general characteristics of galaxies in these systems, such as specific star formation rate, age of the stellar populations, concentration index, colour and local density environment.

  9. Cinemática de galaxias espirales

    NASA Astrophysics Data System (ADS)

    Agüero, M. P.; Díaz, R. J.

    We present preliminary results from the analysis of high-quality rotation curves of ten spiral galaxies. We performed a Fourier analysis of the residues respect to smooth rotation curves, corresponding to previously fitted models with axi-symmetric mass distribution. We studied the relation between the kinematical residues and the morphological features of each galaxy, in R and H bands. We find that the residues associated to the spiral arms have an average amplitude consistent with that expected for perturbations originated in a quasi-stationary density wave pattern.

  10. Agujeros negros supermasivos en galaxias espirales

    NASA Astrophysics Data System (ADS)

    Macchetto, F. D.

    It is now believed that massive black holes exist at the center of all galaxies. Searches with the Hubble Space Telescope have revealed massive central condensations in all those galaxies where the measurements have been carried out. Furthermore, the mass of these central objects appears to correlate with the mass of the galactic bulges and with the velocity dispersion, even in galaxies that do not show any evidence for central activity. This has important consequences for the study of galaxy evolution since it means that central black holes existed or were formed at the very beginning of the galaxy formation process. However many questions remain open; are the central condensations really massive black holes or are they more diffuse objects, such as compact star clusters?; do the black holes masses really correlate with the bulge mass?; are the masses determined with photometric methods really the black hole masses?; do the correlations extend to the low luminosity objects and to spiral galaxies?. To answer some of these questions we have embarked in an HST program to determine the masses of black holes in spiral galaxies directly by measuring the line emission arising from an extended accretion disk. I will present some results from this work.

  11. Climate-induced changes to the ancestral population size of two Patagonian galaxiids: the influence of glacial cycling.

    PubMed

    Zemlak, Tyler S; Walde, Sandra J; Habit, Evelyn M; Ruzzante, Daniel E

    2011-12-01

    Patagonia is one of the few areas in the Southern Hemisphere to have been directly influenced by Quaternary glaciers. In this study, we evaluate the influence that Quaternary glacial ice had on the genetic diversity of two congeneric fish species, the diadromous Galaxias maculatus and the nondiadromous Galaxias platei, using multilocus estimates of effective population size through time. Mid-Quaternary glaciations had far-reaching consequences for both species. Galaxias maculatus and G. platei each experienced severe genetic bottlenecks during the period when Patagonia ice sheet advance reached its maximum positions c. 1.1-0.6 Ma. Concordant drops in effective size during this time suggest that range sizes were under similar constraints. It is therefore unlikely that coastal (brackish/marine) environments served as a significant refuge for G. maculatus during glacial periods. An earlier onset of population declines for G. platei suggests that this species was vulnerable to modest glacial advances. Declines in effective sizes were continuous for both species and lasted into the late-Pleistocene. However, G. maculatus exhibited a strong population recovery during the late-Quaternary (c. 400,000 bp). Unusually long and warm interglacials associated with the late-Quaternary may have helped to facilitate a strong population rebound in this primarily coastal species. PMID:22077139

  12. The relationship between fish assemblages and the helminth communities of a prey fish, in a group of small shallow lakes.

    PubMed

    Fernández, Maria V; Brugni, Norma L; Viozzi, Gustavo P; Semenas, Liliana

    2010-12-01

    Galaxias maculatus (small puyen) is an abundant native fish distributed in lakes and rivers of the Patagonia, and it is the frequent prey of other fishes, fish-eating birds, and mammals. Previous studies have shown that it is parasitized by 33 metazoan species and that the richness and composition of the parasite communities vary between lakes. The aim of the present work was to analyze the relationship between the composition of fish assemblages and the helminth component community structure of G. maculatus . Ten environmentally similar, small, shallow lakes, belonging to the Nahuel Huapi Lake basin, were chosen because of the differences in the native fish assemblages. Parasite community structure in G. maculatus varied according to the fish assemblage of each lake. The presence of the piscivorous fish Percichthys trucha regularly produced variations in the composition and richness at the component and infracommunity levels, as well as the percentage of autogenic parasite species in G. maculatus . PMID:21158611

  13. [Distribution of the infection by Camallanus corderoi (Nemata: Spiruroidea) in different autochthonous hosts and localities of the Valdivia river basin, Chile].

    PubMed

    Torres, P; Franjola, R; Cabezas, X; Neira, A; Covarrubias, C

    1990-01-01

    Six hundred and thirty nine autochthonous fish were examined in 1986-1987 in search for Camallanus corderoi infection on different biotopes from Valdivia River basin (between 39 degrees 30'-40 degrees 00'S, 73 degrees 30'-71 degrees 45'' W). Brachigalaxias bullocki, Galaxias maculatus, Galaxias platei, Aplochiton taeniatus, Cheirodon australe, Basilichthys australis and Cauque mauleanum are new hosts for C. corderoi. Infection by C. corderoi in fish is acquired by ingestion of infected copepods and prevalence and intensity of infection showed differences between host fish and biotopes. In general, infrapopulations of C. corderoi showed overdispersion in different hosts. PMID:2152359

  14. Detection of dwarf gourami iridovirus (Infectious spleen and kidney necrosis virus) in populations of ornamental fish prior to and after importation into Australia, with the first evidence of infection in domestically farmed Platy (Xiphophorus maculatus).

    PubMed

    Rimmer, Anneke E; Becker, Joy A; Tweedie, Alison; Lintermans, Mark; Landos, Matthew; Stephens, Fran; Whittington, Richard J

    2015-11-01

    The movement of ornamental fish through international trade is a major factor for the transboundary spread of pathogens. In Australia, ornamental fish which may carry dwarf gourami iridovirus (DGIV), a strain of Infectious spleen and kidney necrosis virus (ISKNV), have been identified as a biosecurity risk despite relatively stringent import quarantine measures being applied. In order to gain knowledge of the potential for DGIV to enter Australia, imported ornamental fish were sampled prior to entering quarantine, during quarantine, and post quarantine from wholesalers and aquatic retail outlets in Australia. Samples were tested by quantitative polymerase chain reaction (qPCR) for the presence of megalocytivirus. Farmed and wild ornamental fish were also tested. Megalocytivirus was detected in ten of fourteen species or varieties of ornamental fish. Out of the 2086 imported gourami tested prior to entering quarantine, megalocytivirus was detected in 18.7% of fish and out of the 51 moribund/dead ornamental fish tested during the quarantine period, 68.6% were positive for megalocytivirus. Of fish from Australian wholesalers and aquatic retail outlets 14.5% and 21.9%, respectively, were positive. Out of 365 farmed ornamental fish, ISKNV-like megalocytivirus was detected in 1.1%; these were Platy (Xiphophorus maculatus). Megalocytivirus was not detected in free-living breeding populations of Blue gourami (Trichopodus trichopterus) caught in Queensland. This study showed that imported ornamental fish are vectors for DGIV and it was used to support an import risk analysis completed by the Australian Department of Agriculture. Subsequently, the national biosecurity policy was revised and from 1 March 2016, a health certification is required for susceptible families of fish to be free of this virus prior to importation. PMID:26452601

  15. Post-cyclic transmission in Acanthocephalus tumescens (Acanthocephala: Echinorhynchidae).

    PubMed

    Rauque, Carlos A; Semenas, Liliana G; Viozzi, Gustavo P

    2002-01-01

    The aim of this study was to investigate the post-cyclic transmission of Acanthocephalus tumescens (von Linstow, 1896) from Galaxias maculatus Jenyns to Oncorhynchus mykiss (Walbaum). Wild G. maculatus naturally infected with A. tumescens were fed to cultured rainbow trout, which were sacrificed at the second, third and fourth weeks post infection. Normally attached male and female acanthocephalans were recovered alive from the intestine of rainbow trout. Parasites survive at least four weeks post infection, growing and attaining full sexual maturity. Prevalence and mean intensity generally decreased after infection. A. tumescens is the eighth acanthocephalan species in which post-cyclic transmission has been proven. PMID:12194485

  16. Paracreptotrema profundulusi n. sp. and P. blancoi Choudhury, Pérez-Ponce De León, Brooks, and Daverdin, 2006 (Trematoda: Allocreadiidae) from freshwater fishes of the genus Profundulus (Teleostei: Profundulidae) in southern México.

    PubMed

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

    2011-08-01

    Paracreptotrema profundulusi n. sp. (Trematoda: Allocreadiidae) is described from the intestine of the freshwater fishes Profundulus punctatus and P. balsanus (Teleostei: Profundulidae) from the Tehuantepec and the Atoyac-Verde River basins, in Oaxaca, México, in the western extreme of Central America. The new species is distinguished from Paracreptotrema blancoi Choudhury, Pérez-Ponce de León, Brooks, and Daverdin, 2006 , to which it is most similar, and from P. mendezi (Sogandares-Bernal, 1955) Choudhury, Pérez-Ponce de León, Brooks, and Daverdin, 2006 , by the caeca extending beyond the testes, vitelline follicles that invade the postesticular area, and uterus with transverse loops located mainly between the testes and the genital pore. Paracreptotrema blancoi was collected from the same host species and also from Profundulus oaxacae. Here, we provide data that show its broad distribution in several river basins of Neotropical southern México, including the Papagayo River basin, Guerrero, México, and the Atoyac-Verde and Tehuantepec river basins, and other rivers in Oaxaca, México. Freshwater fishes of the Profundulidae are endemic to Central America and host a helminth fauna that includes at least 4 species found only in these hosts. PMID:21506847

  17. 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

  18. 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. PMID:25834774

  19. Variable survival across low pH gradients in freshwater fish species.

    PubMed

    Jellyman, P G; Harding, J S

    2014-11-01

    A series of 14 day experiments was conducted on five common New Zealand fish species (redfin bully Gobiomorphus huttoni, inanga Galaxias maculatus, brown trout Salmo trutta, longfin eel Anguilla dieffenbachii and koaro Galaxias brevipinnis) to assess the effect of pH on survival and changes in body mass. No species survived in water of pH <4 although there was 100% survival of all adults at pH 4.5, G. maculatus larvae were also tested and had high mortality at this pH. Results suggest that adults are tolerant of low-pH waters; however, successful remediation of anthropogenically acidified streams will require an understanding of the susceptibility to low pH on different life cycle stages. PMID:25230112

  20. Biogeography of a southern hemisphere freshwater fish: how important is marine dispersal?

    PubMed

    Waters, J M; Dijkstra, L H; Wallis, G P

    2000-11-01

    Galaxias maculatus is one of the world's most widely distributed freshwater fish. This species has a marine-tolerant juvenile phase, and a geographical range extending through much of the southern hemisphere. We conducted phylogeographic analyses of 163 control region haplotypes of G. maculatus, including samples from New Zealand (five locations), Tasmania (one location) and Chile (one location). A lack of genetic structure among New Zealand samples suggests that marine dispersal facilitates considerable gene flow on an intra-continental scale. The discovery of a Tasmanian-like haplotype in one of 144 New Zealand samples indicates that inter-continental marine dispersal occurs but is insufficient to prevent mitochondrial DNA differentiation among continents. The sister relationship of Tasmanian and New Zealand clades implies that marine dispersal is an important biogeographical mechanism for this species. However, a vicariant role in the divergence of eastern and western Pacific G. maculatus cannot be rejected. PMID:11091317

  1. Evolución de galaxias y QSOs Modelo evolutivo-explosivo-compuesto: fase final de galaxias y origen explosivo de galaxias enanas

    NASA Astrophysics Data System (ADS)

    Lípari, S. L.; Terlevich, R. J.; Taniguchi, Y.; Mediavilla, E.; Bergmann, M.; García-Lorenzo, B.; Sánchez, S. F.; Zheng, W.; Punsly, B.; Merlo, D. C.

    2015-08-01

    We present new results of our evolutionary-explosive- composite model of Galaxies, Quasars and AGNs. In particular: we explain the concept of final phase of a galaxy and the fact that at least a fraction of dwarf galaxies can be explained by this model (as a stage prior to the final). In addition, we explain that the prototype of the starburst galaxy M82 could be a dwarf galaxy previous to the final phase. Also, we discuss new Gemini observations BAL + FeII + IR medium-high redshift QSOs. To interpret these results we performed an introduction to our model and some of the most previous relevant results, including: (i) Evolution Diagram of Galaxies, QSOs and AGNs; (ii) Our Evolutionary-Explosive-Compound Model explains in the same process: the interaction of ``Starburst'' and Supermassive black holes that generate hypernova, the Origin of Ultra Energetic Cosmic Rays and Dark Matter. (iii) Observation and Theory of Formation and Final Phase of Galaxies via hypernova explosions in QSOs and AGNs.

  2. Efectos de extincin en curvas de rotacin de galaxias espirales

    NASA Astrophysics Data System (ADS)

    Valotto, C.; Giovanelli, R.

    Observations show that the slope of the inner part of the H?/[NII] rotation curves of disk galaxies is depressed by extinction: at fixed luminosity, the observed slope is in fact seen to depend on the disk inclination to the line of sight. Using a simple extinction model, we are able to reproduce well the observed trends. The model assumes an exponential distribution, both in the radial and z directions, identical for star-forming regions and dust. Fits to the data are optimized by varying the scale height and scale length of absorbers, as well as the disk's central optical depth ?o, as seen face-on. The observations indicate that disk central opacity increases with total luminosity. Model fits for the most luminous galaxies (brighter than M-5 log h=-21.4 in the I band) yield ?o ? 3.5+4.0-2.0, near ?=0.66 ?m. The large uncertainty on the inferred value of ?o is due to the poorly known characteristics of the distribution of absorbers in the disk, as well as to the likelihood of strong departures from an exponential radial distribution near the galaxy centers.

  3. Grupos de galaxias con corrimiento al rojo intermedio

    NASA Astrophysics Data System (ADS)

    Salerno, J. M.; Muriel, H.; Alonso, M. V.; Valotto, C.

    2015-08-01

    We present the construction of a catalog of groups of galaxies obtained through a sample of 677 spectra obtained with VIMOS-MOS spectrograph at the VLT. The sample has a redshift range and includes randomly selected galaxies brighter than in the R band. Groups of galaxies are identified using the algorithm Friends-of-friends (FOF). Linking lengths are taken as and . We also performed a visual reconstruction of the FOF groups. Finally, the basic properties of groups were estimated: velocity dispersion, virial mass and radius.

  4. Ruprecht 44 y la estructura espiral externa de la Galaxia

    NASA Astrophysics Data System (ADS)

    Giorgi, E. E.; Solivella, G. R.; Vázquez, R. A.; De Laurenti, M. A.

    We present first results of a photometric study UBVI CCD; complemented with MK spectral classification and 2MASS data; focusing on the region of the open cluster Ruprecht 44. This cluster is in an area of very low interstellar absorption; through which it is possible examine in the optical range the spiral structure outside the solar circle. Precise distances determination of blue stars in the field of this cluster enable analyze; with other data recently obtained; the structure of great design in the third galactic quadrant. FULL TEXT IN SPANISH

  5. Componentes contra-rotantes en simulaciones de galaxias disco

    NASA Astrophysics Data System (ADS)

    Algorry, D. G.; Abadi, M. G.

    In this work we present a dynamical analysis of two simulated disk galaxies, having both counter-rotating stellar components. The dynamical properties of the stellar particles of these galaxies, such as velocity, energy and circu- larity of the orbits, show that there is an internal component which rotates in opposite direction to the galactic disk. This study allows us to com- pare these simulated galaxies to those found in the last few years having counter-rotating components. FULL TEXT IN SPANISH

  6. Estructuras circumnucleares en la galaxia Seyfert interactuante NGC 1241

    NASA Astrophysics Data System (ADS)

    Díaz, R. J.; Carranza, G.; Dottori, H.

    We have studied the rotation curve and morphology of the central 10 kiloparsecs (~40'') of NGC 1241 obtaining 50 radial velocity measurements in three different position angles. These observations indicate a large velocity gradient of 70 km/sec/('') in the central 5''. The fitting of different density distribution laws to the derived rotation curve indicates a mass of ~ 9 E9 Msolar in the inner kpc. HST-NICMOS images show the presence of a circumnuclear star formation ring at radius ~ 2.8'' (720 pc). This ring is more defined than most of the known cases and harbours a mini-bar and nuclear spiral arms with a sense of rotation opposite than the main spiral arms. This morphological evidence suggest the presence of a dynamically decoupled system inside the circumnuclear ring. As in other cases studied by us, the ring seems to be inside an Inner Lindblad Resonance and the Lindblad curve ω-κ/2 for this object begins to drop for Rmax = 400 pc (~1.5''), but the limited spatial resolution does not allow us to find out a definitive evidence for the existence of a second ILR inside at inner radii. Up to date there is no published morphological or kinematical evidence for the presence of a second ILR at such small radii, a necessary ingredient for the presence of circumnuclear ring of star formation, considering the results of recent hydrodynamic simulations. We have proposed the observation of NGC 1241 with better instruments in order to extend the rotation curve to the central 2'', unveil the presence of a second inner resonance, study in detail the structural properties of the nuclear counterrotating arms and establish accurate models of mass distribution in galaxies with circumnuclear rings. This program has been awarded with Band 1 observing time at the Gemini North Telescope Quick Start Stage (Brasil and Argentina).

  7. Distribucion de Hidrogeno Neutro EN Galaxias Espirales de Coma

    NASA Astrophysics Data System (ADS)

    Bravo-Alfaro, H.; van Gorkom, J. H.; Balkowski, C.; Cayatte, V.

    1998-11-01

    We have carried out a study of environmental effects on the properties and evolution of galaxies in clusters. We have studied the HI content of spiral galaxies in two nearby clusters, Abell~262 and Abell~1656 (Coma), from 21cm observations obtained with the Westerbork Synthesis Radio Telescope and with the Very Large Array. These observations have provided us the HI images of a sample of 11 galaxies in Abell~262, and 19 in Coma. We have computed the HI content and analyzed the HI distribution of detected galaxies, what enabled us to study the environmental effects on cluster galaxies, as well as the possible involved physical mechanisms. We confirm the tendency of HI deficient galaxies to be closer to the cluster core. We also estimate in a quantitative fashion the role that ram pressure stripping can play in the central cluster region, where the intra--cluster medium shows its most hostile density and temperature conditions. Most of galaxies showing a perturbed neutral hydrogen distribution are likely affected by ram pressure. Five star--bursting galaxies and one post--starburst were detected among the 19 HI detected objects in Coma. We conclude, from the analysis of their HI distribution and from the correlations of their positions in the cluster and U--V colors with the HI deficiency, that some cluster galaxies may follow an evolutionary sequence: galaxies would first become blue because of the interaction with the ICM, what trigger a burst of star--formation. Galaxies appear at this stage as HI deficient. The next step in this sequence would be the PSB stage, where galaxies arrive once they quench most of their HI reservoir and the star--formation stops in a short time-scale. The deep neutral gas stripping explain why these galaxies are hardly detected in HI. None of the closest galaxies to NGC~4839 have been detected in our observations around the Southwest group, what hints a previous passage across the cluster core with the consequence of a stripping process. The present work shows how useful the HI observations can be to study the interaction mechanisms of cluster galaxies with the intra--cluster medium, as well to analyze the cluster substructures.

  8. Agujeros negros de masas estelares en la Galaxia

    NASA Astrophysics Data System (ADS)

    Cúneo, V. A.; Gómez, M. N.

    In this contribution we present a catalogue of stellar mass black-hole candidates; mainly in our galaxy; that represents the largest database available in the literature to date. The confirmed candidates; all of them in binary systems; are analyzed in detail. FULL TEXT IN SPANISH

  9. Superestructuras y las propiedades del clustering de galaxias brillantes

    NASA Astrophysics Data System (ADS)

    Yaryura, C. Y.; Lares, M.; Luparello, H. E.; Paz, D. J.; Lambas, D. G.; Padilla, N.; Sgró, M. A.

    This article is based on the results presented in Yaryura et al. (2012, MNRAS, 426, 708), where the clustering properties of galaxies is analyzed as a function of their large-scale environment. In order to characterize the environment on large scales, we use the catalogue of future virialized superstructures (FVS) by Luparello et al. (2011, MNRAS, 415, 964) and separate samples of luminous galaxies according to whether or not they belong to FVS. The correlations have similar amplitudes at scales r ≤ 1 h^{-1} Mpc. We have performed a similar analysis using a semi-analytic implementation in a ΛCDM cosmological model, where we found that the cross-correlation functions depend on the large-scale structures in a similar way to the observations. FULL TEXT IN SPANISH

  10. Validating the use of embryonic fish otoliths as recorders of sublethal exposure to copper in estuarine sediments.

    PubMed

    Barbee, Nicole C; Greig, Alan; Swearer, Stephen E

    2013-07-01

    In this study we explore the use of fish otoliths ('earbones') as a tool for detecting exposure to heavy metals in sediments. Because otoliths are metabolically inert and incorporate chemical impurities during growth, they can potentially provide a more permanent record of pollutant exposure history in aquatic environments than soft tissues. To validate this technique we cultured embryos of a native Australian fish, the common Galaxias (Galaxias maculatus), in the laboratory on sediments spiked with copper in a concentration gradient. Our aims were to test whether exposure to copper contaminated sediments is recorded in the otoliths of embryos and determine over what range in concentrations we can detect differences in exposure. We found elevated copper levels in otoliths of embryos exposed to high copper concentrations in sediments, suggesting that otoliths can be used as a tool to track a history of exposure to elevated copper levels in the environment. PMID:23628888

  11. Effect of ramp length and slope on the efficacy of a baffled fish pass.

    PubMed

    Baker, C F

    2014-02-01

    This study evaluated the effect of ramp length and slope on fish passage over baffled ramps with 15° and 30° gradients. Three fish species indigenous to New Zealand were tested: the redfin bully Gobiomorphus huttoni, the common bully Gobiomorphus cotidianus and the inanga Galaxias maculatus with ramp lengths of 3, 4·5 and 6 m. As slope and ramp length increased, passage success rate decreased for G. maculatus and G. cotidianus. At a slope of 15°, both G. maculatus and G. cotidianus could pass all ramp lengths tested with the highest success rate on the 3 m ramp. As the gradient increased to 30°, G. maculatus could only pass the 3 m ramp, and G. cotidianus were incapable of passing any ramp. Gobiomorphus huttoni were the only test species capable of climbing the wetted margin of the ramps. Increasing ramp slope significantly reduced passage success for G. huttoni, but ramp length, up to the maximum used in this study, had no significant influence on successful passage. PMID:24417428

  12. Component population study of Acanthocephalus tumescens (Acanthocephala) in fishes from Lake Moreno, Argentina.

    PubMed

    Rauque, Carlos A; Viozzi, Gustavo P; Semenas, Liliana G

    2003-03-01

    Seasonal samples of all fish species from Lake Moreno were taken in order to determine the presence of paratenia, to evaluate the status of the hosts and to characterise the transmission of Acanthocephalus tumescens (von Linstow, 1896) at the component population level. Prevalence, mean abundance, mean intensity, numbers of gravid females, relative abundance of the different fish species, relative output of eggs and relative flow rates for each host species were computed. Acanthocephalus tumescens showed low host specificity, successfully parasitizing six out of eight fish species present in the lake. No paratenic infection was registered. If prevalence, mean abundance, and number of gravid females are considered, host species can be placed in a continuum from the most to least suitable as follows: Galaxias platei Steindachner, Diplomystes viedmensis (Mac Donagh), Oncorhynchus mykiss (Walbaum), Salvelinus fontinalis (Mitchill), Percichthys trucha (Cuvier et Valenciennes) and Galaxias maculatus (Jenyns). However, when parasite flow rates and egg output were calculated, including relative abundance of each fish species, the continuum was rearranged as follows: P. trucha, O. mykiss, G. platei / G. maculatus, S. fontinalis and D. viedmensis. The first four species would be the main contributors to the population of A. tumescens in this lake, P. trucha being the major one. Different regulatory and non-regulatory mechanisms are suggested. PMID:12735727

  13. Extensive genetic divergence among Diptychus maculatus populations in northwest China

    NASA Astrophysics Data System (ADS)

    Meng, Wei; Yang, Tianyan; Hai, Sa; Ma, Yanwu; Cai, Lingang; Ma, Xufa; Gao, Tianxiang; Guo, Yan

    2015-05-01

    D. maculates is a kind of specialized Schizothoracinae fish has been locally listed as a protected animal in Xinjiang Province, China. Ili River located in north of Tianshan Mountain and Tarim River located in north of Qinghai-Tibetan Plateau were two main distribution areas of this fish. To investigate the genetic diversity and genetic structure of D. maculates, four populations from Tarim River system and two populations from Ili River system were collected in this study. A 570-bp sequence of the control region was obtained for 105 specimens. Twenty-four haplotypes were detected from six populations, only Kunes River population and Kashi River population shared haplotypes with each other. For all the populations examined, the haplotype diversity ( h) was 0.904 8±0.012 6, nucleotide diversity (π) was 0.027 9±0.013 9, and the average number of pairwise nucleotide differences ( k) was 15.878 3±7.139 1. The analysis of molecular variance (AMOVA) showed that 86.31% of the total genetic variation was apportioned among populations, and the variation within sampled populations was 13.69%. Genetic differences among sampled populations were highly significant. F st statistical test indicated that all populations were significantly divergent from each other ( P<0.01). The largest F st value was between Yurungkash River population and Muzat River population, while the smallest F st value was between Kunes River population and Kashi River population. NJ phylogenetic tree of D-loop haplotypes revealed two main clades. The neutrality test and mismatch distribution analysis suggested that the fish had went through a recent population expansion. The uplift of Tianshan Mountain and movement of Qinghai-Tibetan Plateau might contribute to the wide genetic divergence of D. maculates in northwest China.

  14. Fine structural analysis of a teleost exocrine pancreas cellular components - a freeze-fracture and transmission electron microscopic study.

    PubMed

    Stipp, A C; Ferri, S; Sesso, A

    1980-01-01

    The normal exocrine pancreas of Pimelodus maculatus (Teleostei) has been studied by freeze-fracture and conventional transmission electron microscopy. 4 cellular types in the acini are observed: the acinar cells, the argentaffin cells, the intermediate cells and the centroacinar cells. The most proeminent cytoplasmic feature of the acinar cells is that the well developed rough endoplasmic reticulum, which appear predominantly under the vesicular form. The argentaffin cells are found lodged between the acinar cells and duct cells, in the connective tissue they are isolated principally that surrounds the ducts. The typical granules are the cytoplasmic component wich characterize the argentaffin cells. The indermediate cells are characterized by the presence of two distinct granule types: one resembling that found in the endocrine cells and the other resembling the granules of the acinar cells. The centroacinar cells is similar that found in other species. PMID:7396226

  15. Life-cycle stages of a Posthodiplostomum species (Digenea: Diplostomidae) from Patagonia, Argentina.

    PubMed

    Ritossa, Luciano; Flores, Verónica; Viozzi, Gustavo

    2013-10-01

    In Patagonia, populations of the galaxiid fish Galaxias maculatus are parasitized by metacercariae of a species of Posthodiplostomum (Digenea: Diplostomidae). The aim of this work was to describe larval and adult stages of this species in experimental and natural hosts from an Andean Patagonian lake. Specimens of G. maculatus and the pulmonate snail, Anisancylus obliquus, were collected in Patagua Lake. The snails were isolated in individual containers to observe emergence of cercariae, dissected, and examined under a stereoscopic microscope to record sporocysts and cercariae. Fish were examined to obtain metacercariae, and uninfected fish from Gutiérrez Lake were exposed to cercariae from A. obliquus to obtain experimental metacercariae. Chicks and mice were infected with metacercariae from naturally infected G. maculatus to obtain experimental adults. Specimens recovered belong to Posthodiplostomum sp. on the basis of morphological features. This is the first description of sporocysts, cercariae, metacercariae, and adults stages of a Posthodiplostomum species in Patagonia, including data about its natural intermediate hosts. PMID:23628085

  16. The importance of cutaneous gas exchange during aerial and aquatic respiration in galaxiids.

    PubMed

    Urbina, M A; Meredith, A S; Glover, C N; Forster, M E

    2014-03-01

    The Canterbury mudfish Neochanna burrowsius was found to be a pseudo-aestivating galaxiid with a low metabolic rate and significant cutaneous oxygen uptake (c. 43%) in both air and water. Another galaxiid, inanga Galaxias maculatus, had a higher metabolic rate in both media but the proportion of oxygen uptake met by cutaneous respiration rose significantly from 38 to 63% when the fish were exposed to air. Besides its important role in oxygen uptake, the skin of both species also contributed significantly to excretion of carbon dioxide in air, indicating the critical role of the integument as a respiratory tissue. In air, G. maculatus may increase cutaneous gas exchange to meet metabolic demands owing to the reduced utility of the gills, but as emersed G. maculatus were only able to maintain metabolic rates at c. 67% of that measured in water, this strategy probably only permits short-term survival. By contrast, the low and unchanging metabolic rate in water and air in N. burrowsius is a feature that may facilitate tolerance of long periods of emersion in the desiccating environments they inhabit. PMID:24417441

  17. Evolución en Núcleos Activos de Galaxias y QSOs I. Relación Starbursts y AGNs en Galaxias Próximas

    NASA Astrophysics Data System (ADS)

    Lípari, S.; Merlo, D.; Moyano, M.

    We have started a new part of our program: ``Study of Evolution of AGNs & QSOs''. This new part is mainly a study of the relation between Starbursts and AGNs-QSOs in nearby galaxies (using our model of Evolutive, Composite & Explosive AGNs-QSOs). In particular, we have started spectrophotometric and imaging observations at CASLEO, Bosque Alegre, Gemini, Calar Alto, etc. This study also includes the analysis of Archive Data. Here we show our first results for NGC 1097. FULL TEXT IN SPANISH

  18. Estudio de Evolución de los Núcleos Activos de Galaxias y QSOs: II. Búsqueda de Supernovas en Galaxias Pr'oximas con AGNs y Starburst

    NASA Astrophysics Data System (ADS)

    Merlo, D.; Lípari, S.; Moyano, M.

    Several lines of observational evidences suggesting that supernovae and hypernovae events play a main role in evolution of galaxies, AGNs and QSOs. In order to search more detailed information, we have started a study and detection of supernovae and hypernovae in the nuclei of nearby active galaxies obtaining high-resolution spectra and images in the standard UBVRI filters mainly from CASLEO, Bosque Alegre and data from archive of HST, ESO and La Palma observatories. In this paper we present the first preliminary results obtained in this program. FULL TEXT IN SPANISH

  19. Fotometria de Washington de cumulos abiertos proyectados en direccion hacia el centro de la Galaxia

    NASA Astrophysics Data System (ADS)

    Marcionni, N.; Clariá, J. J.; Parisi, M. C.; Palma, T.; Oddone, M. A.; Ahumada, A. V.; Piatti, A. E.

    We present preliminary results obtained from the photometric analysis in the and bands of the Washington photometric system of four poorly studied open clusters (OCs): Dias6; NGC5381; Ruprecht128 and Czernik37; projected in the Galactic center direction. We derived their fundamental parameters from their (; ) color-magnitude diagrams; using theoretical isochrones computed for the Washington system. The present results are part of a major project which aims at characterizing almost a hundred OCs observed and analyzed in a homogeneous way. FULL TEXT IN SPANISH

  20. Cúmulos globulares en galaxias elípticas aisladas: el peculiar caso de NGC7507

    NASA Astrophysics Data System (ADS)

    Caso, J. P.; Richtler, T.; Bassino, L.

    We present results of the study of the glolular cluster system of NGC7507. The number of members of the system is calculated; and compared with other elliptical galaxies from literature. FULL TEXT IN SPANISH

  1. El origen de las galaxias esferoidales en simulaciones Cosmológicas

    NASA Astrophysics Data System (ADS)

    Algorry, D. G.; Abadi, M. G.

    We use the GIMIC cosmological hydrodynamical simulations to perform a study of the properties of spheroidal galaxies formed without merger events. We select a sample of galaxies with stellar mass greater than 10 M and we classified them according to the degree of rotation support through the ratio of the rotational kinetic energy respect to the total at redshift z=0. Taken only those with ; we focus on those with accreted mass fraction less than 20 to ensure that they are merger free. We found that these spheroidal galaxies have stellar mass M M and have an important barred component. Interestingly; we found that in many cases the simulated galaxies present two external rings around the bar being both coplanar and counter-rotating to each other. FULL TEXT IN SPANISH

  2. Una nueva galaxia IR con nucleo compuesto: Seyfert 1.5 y estallido de formacion estelar

    NASA Astrophysics Data System (ADS)

    Lipari, S. L.; Merlo, D. C.; Moyano, M. M.

    Optical aperture spectroscopy and CCD broad- and narrow-band images are presented for the barred Seyfert 1 galaxy: IRAS 22117-3903. IRAS data are also used to analyse this object. The CTIO broad band CCD imaging show interesting morphological features: a compact nucleus with a prominent bar; two bright spiral arms; and a partial/segmented inner ring. The narrow-band imaging show that the nuclear H+[NII] emission is concentrate mainly in the nucleus. We find optical spectral features characteristic of a Seyfert 1.5 nucleus; i.e.; showing hydrogen emission lines with broad and narrow components. We detected high excitation emission lines ([CaV]+[FeXIV]; [FeVII]). We study the stellar population in the nuclear region. We find that the stellar population that represent quite well the nuclear stellar population is an average of spiral galaxies dominated by the old population plus a contribution of young stars. Physical conditions are derived for the narrow emission line region; and we detected very high electron temperature (T=4400045000 K); untypical for the ordinary AGNs and probably associated to shocks in a starburst component. Finally; at the optical and IR wavelength; we find properties typical of an nucleus with compound nature; in good agreement with the AGN/QSOs evolutionary model of Lípari ; Terlevich (2006; ; 368; 1001). FULL TEXT IN SPANISH

  3. Interacciones de galaxias: sistemas co-rotantes y contra-rotantes

    NASA Astrophysics Data System (ADS)

    Mesa, V.; Duplancic, F.; Alonso, S.; García Lambas, D.

    In this paper we present a sample of interacting galaxy pairs with tidal tails. We perform a visual cassification according to the sense of rotation of the spiral arms of each member of the tidal system. We study general features of interacting galaxies such as mass content in stars (M^*), luminosity ratios and local environment through an analysis of the Σ_5 parameter. FULL TEXT IN SPANISH

  4. Espectroscopía infrarroja de la galaxia Seyfert NGC6300

    NASA Astrophysics Data System (ADS)

    Gaspar, G.; D‘Ambra, A.; Díaz, R. J.; Gunthardt, G.; Gómez, P.

    2015-08-01

    Here we present a spectroscopic study in the near infrared band of the active galaxy NGC 6300, with spectra obtained with the spectrograph Flamingos 2 of the telescope Gemini South. The spectra were taken in the range 1 to 2.4 mm, with a mean spatial resolution of 0.6'', in this work we present preliminary results for a single band, . This global study is based in the analysis of the relative contributions in the emission of the Seyfert nuclei and the circunnuclear star formation to discuss later the role of the AGN in the scenarios of dynamical evolution of galaxies. We present the detection of a broad component in the Pa emission line, an unexpected feature in this galaxy so far classified as a 2 type.

  5. Análisis de la formación de galaxias en grupos

    NASA Astrophysics Data System (ADS)

    Pérez, M. J.; Tissera, P.; García Lambas, D.

    The actual cosmological paradigm postulates that structure formation occurs in a hierarchical way. In such scenarios, interactions among galaxies are frequent and play an important role in determining their properties, and particularly, in the regulation of star formation. Observations show that interactions and collisions can increase the star formation rate (Larson & Tinsley 1978; Donzelli & Pastoriza 1997; Barton et al 1998). In particular, recent observational results (García Lambas, Tissera, Alonso & Coldwell, 2003) show that star formation in galaxy pairs is significantly enhanced over that of isolated galaxies with the same redshift distribution. Theoretical interpretation of these observational results could be associated to the dynamical stability of galactic systems. Numerical simulations show that disc galaxies without bulges or with small ones, tend to develop instabilities induced by tidal interactions which produce gas inflows and trigger star formation (Mihos & Hernquist 1996; Domínguez-Tenreiro, Tissera & Sáiz 1998). Although simulations and observations show the effects of galaxy interactions on the star formation, intrinsic properties of galaxies in pairs must play a crucial role due to high observed fraction of galaxies pairs with low star formation rate (García Lambas et al 2003). In order to see if these observational results are reproduced in hierarhical clustering scenarios, we study the star formation of galaxy pairs, as well as any possible effects provoked by interactions on other astrophysical properties, such the chemical ones. For this purpose, we use hydrodynamical simulations consistent with a CDM model: Ω=1, Λ=0 and H0=50 km s-1 Mpc-1, which include star formation and chemical evolution (Mosconi et al 2001). We analyzed three different realizations of the power spectrum in the redshift range of the 2dFGRS catalog (García Lambas et al. 2003). Identified structures were classified as isolated galaxies and galaxies in closed pairs, and then grouped according to the environment. Firstly, the classification was carried out by using the 3D velocity and spatial separations. In agreement with the observational results, we found that closed encounters with a relative 3D distances r<30 kpc, show an enhancement of star formation rate with respect to the mean field value (bar{b}=3.04) calculated considering galaxies with r > 100 kpc. Preliminary results show the media abundance of (O/H) of the stellar populations in closed pairs is systematically higher than that value for field galaxies, suggesting a tendency with the relative 3D distances, which can be associated to a major production of SNII originated by the enhancement of star formation in closed pair galaxies. The interstellar medium shows the same trend but with lower mean abundance values suggesting an accretion of low metallicity gas. Fe is produced mainly by SNI, with a delay of 0.1 Gyr; therefore, it is not coupled to present star formation activity but to the history of star formation. Our results suggest a certain trend for Fe to be higher at smaller relative 3D distances. The higher Fe abundances indicate that closer pairs might have a major old stellar population. Future works involved the performance of a mock pair catalog by projecting the 3D-simulated pair galaxies and the study of the properties of projected pairs and the effects of interlopers on the conclusions drawn from them (Pérez et al., in preparation).

  6. Cinematica del gas ionizado y perfiles de luminosidad de las Galaxias Porotos Verdes

    NASA Astrophysics Data System (ADS)

    Diaz, R. J.; Aguero, M.; Schirmer, M.; Holheim, K.; Levenson, N.; Winge, C.

    We present preliminary spectroscopic results of a sample of green bean galaxies (GBG); known to show ultra-luminous; galaxy-wide; narrow-line regions. We analyze Gemini GMOS-S;N spectra of a sample of 12 GBG in order to obtain emission line ratios; gas kinematics and luminosity profiles in some continuous bands. We report here new results that confirm that the 5008 emission extends from 5 to 17 kpc; in all cases scales similar or larger than the stellar continuums at the spectra. In the extreme case of J145533.6+044643 the emission reaches a diameter of 17.51.6kpc. We find that the continuum half light radii extend from 3 to 7 kpc; the largest scale radius at shortest wavelengths; which is consistent with the scale lengths of large spiral galaxies or merging systems. Another new result is that the spatial variation of the continuum color profiles indicate the presence of extinction and possibly star formation. FULL TEXT IN SPANISH

  7. Dinámica global en galaxias elípticas

    NASA Astrophysics Data System (ADS)

    Pérez, M. J.; Cincotta, P. M.; Giordano, C. M.

    Con el propósito de determinar propiedades dinámicas globales en sistemas triaxiales no integrables, utilizamos una nueva herramienta conocida como ``Mean Exponential Growth factor of Nearby Orbits'' (MEGNO), introducida por Cincotta y Simó (2000). Esta técnica no sólo resulta eficiente para investigar ambas componentes del espacio fase, regular y caótica, sino que también, provee una medida de la hiperbolicidad en el dominio caótico que coincide con la dada por el Lyapunov Characteristic Number (LCN). Previamente este método ha sido aplicado al estudio de modelos simples, y últimamente en el campo de la Mecánica Celeste, al estudio de sistemas planetarios extrasolares. En esta presentación, ilustraremos algunas de las propiedades más importantes del MEGNO, aplic& acute;andolo al potencial tridimensional de Stäckel perturbado.

  8. La distribución multimodal de cúmulos globulares en la galaxia NGC 1399

    NASA Astrophysics Data System (ADS)

    Forte, J. C.; Ostrov, P. G.

    Se presenta una discusión de las características del diagrama de dos colores para un muestreo de 400 cúmulos globulares asociados con NGC 1399. Los resultados indican la presencia de, por lo menos, tres familias de cúmulos. La naturaleza de una cuarta componente, muy azul, no es clara aunque podría tratarse de cúmulos ``sueltos" asociados con el sistema de Fornax.

  9. La abundancia de galaxias y halos de materia oscura en el universo CDM

    NASA Astrophysics Data System (ADS)

    Abadi, M. G.; Benítez-Llambay, A.; Ferrero, I.

    A long-standing puzzle of CDM cosmological model concerns to the different shape of the galaxy stellar mass function and the halo mass function on dwarf galaxy scales. Dwarf galaxies are much less numerous than halos massive enough to host them; suggesting a complex non-linear relation between the mass of a galaxy and the mass of its surrounding halo. Usually; this is reconciled by appealing to baryonic processes that can reduce the efficiency of galaxy formation in low-mass halos. Recent work applying the abundance matching technique require that virtually no dwarf galaxies form in halos with virial mass below . We use rotation curves of dwarf galaxies compiled from the literature to explore whether their total enclosed mass is consistent with these constraints. Almost one-half of the dwarfs in our sample are at odds with this restriction; they are in halos with masses substantially below . Using a cosmological simulation of the formation of the Local Group of galaxies we found that ram-pressure stripping against the cosmic web removes baryons from low-mass halos without appealing to feedback or reionization. This mechanism may help to explain the scarcity of dwarf galaxies compared with the numerous low-mass halos expected in CDM and the large diversity of star formation histories and morphologies characteristic of faint galaxies. FULL TEXT IN SPANISH

  10. Hidrógeno neutro en la galaxia Fourcade-Figueroa.

    NASA Astrophysics Data System (ADS)

    Colomb, F. R.; Loiseau, N.; Testori, J. C.

    The H I 21 cm line has been detected in the direction of the Fourcade-Figueroa Galaxy. This is a late-type galaxy seen almost edge-on with a velocity of 824 km s-1. The neutral hydrogen dimensions are found to be approximately twice its optical dimensions. The mass and other parameters of the galaxy are derived.

  11. Genetic variation, population structure and cryptic species within the black mudfish, Neochanna diversus, an endemic galaxiid from New Zealand.

    PubMed

    Gleeson, D M; Howitt, R L; Ling, N

    1999-01-01

    To investigate the phylogenetic relationships and geographical structure among landlocked populations of the black mudfish, Neochanna diversus, mitochondrial DNA nucleotide sequence data were sampled from seven populations from the Waikato and Northland regions of New Zealand. The complete D-loop region was sequenced from 70 individuals, with 913 bp from the tRNA-pro end used in population and phylogenetic analysis. A tandem repeat array, which ranged in size up to 200 bp, was found in most populations at the 3' end of the D-loop that was not able to be aligned for analysis. Of the seven sites sampled, two from Northland exhibited significant sequence divergence from all other sites. There was also a clear distinction among remaining Northland sites and those from the Waikato. An additional 518 bp segment of the 16S region was sequenced from all sites and compared with the other New Zealand mudfish species, N. apoda, N. burrowsius and the Tasmanian mudfish Galaxias (Neochanna) cleaveri using Galaxias maculatus as an outgroup. Both D-loop and 16S sequence data provided strong evidence for a cryptic species of mudfish present in Northland. The significant genetic structure apparent in the black mudfish appears most probably to be attributed to geological conditions during the Pliocene, where peat wetlands became apparent in the Waikato while Northland consisted of disjunct 'islands'. Conservation and management of these populations must take into account the historical processes that have shaped these patterns of genetic diversity. PMID:9919697

  12. A new hedrurid species (Nematoda) from galaxiid fishes in Patagonia (Argentina) and infection of amphipods as intermediate host.

    PubMed

    Brugni, Norma L; Viozzi, Gustavo P

    2010-02-01

    During a parasite survey of galaxiid fishes (Galaxiidae) from Patagonian Andean lakes, a new species of nematode, Hedruris suttonae n. sp. was collected from the stomach of the native Galaxias maculatus (Jenyns) and G. platei (Steindachner). Specimens were examined by light and scanning electron microscopy, especially head morphology, female caudal prehensile structure, and distribution of spines. The new species is distinguished by body and tail size, morphology and size of spicules, the arrangement of caudal papillae in the male, the female caudal hook, and size of eggs. Hyalella patagonica (Ortmann), a Neotropical species of Amphipoda, is reported as its natural intermediate host. Data regarding prevalence and mean intensity in the intermediate and definitive hosts are included. The diet and habitat of the hosts, the percentage of gravid females, the high values of prevalence, and mean intensity in galaxiid fishes, as well as the wide distribution of H. suttonae , collectively indicate that, in these oligotrophic Andean lakes, G. maculatus and G. platei are true definitive hosts of this nematode. PMID:19737026

  13. Complete mitochondrial genome of Schizopygopsis malacanthus (Teleostei: Cypriniformes: Cyprinidae).

    PubMed

    Zeng, Yu; Chen, Yong-Bo; Pan, Bao-Zhu; Zhang, Da-Wen

    2016-03-01

    The complete mitochondrial genome of Schizopygopsis malacanthus is a circular molecule of 16,677?bp in size, containing 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and 2 main non-coding regions (the control region and the origin of the light strand replication). Most of the genes are encoded on the heavy strand, except for ND6 and eight tRNAs. The control region is 938?bp in length and located between the tRNA(Pro) and tRNA(Phe) genes, some typical conserved elements (TAS, CSB1-3 and CSB D-F) were found in this region. All these features reflect a typical vertebrate mitochondrial gene arrangement of the S. malacanthus. PMID:25103444

  14. The complete mitochondrial genome of Jinshaia sinensis (Teleostei, Balitoridae, Balitorinae).

    PubMed

    Que, Yan-Fu; Xu, Dong-Mei; Xiong, Mei-Hua; Yang, Zhi; Gao, Shao-Bo; Shi, Fang

    2016-03-01

    Jinshaia sinensis is an endemic and typical fish which is successfully adaptive to mountain torrents in the upper stream of the Yangtze River and its tributaries. In this study, the complete mitogenome sequence of J. sinensis has been first sequenced by DNA sequencing based on the PCR fragments. The mitogenome, consisting of 16,567 base pairs (bp), had typical vertebrate mitochondrial gene arrangement, including 13 protein coding genes, 22 transfer RNAs, 2 ribosomal RNA genes and a noncoding control region (CR). The overall base composition of J. sinensis is 30.37% A, 28.82% C, 16.59% G, and 24.22% T, with a relatively a slight AT bias of 54.59%. CR of 903?bp length is located between tRNA(Pro) and tRNA(Phe). The complete mitochondrial genome may provide fundamental informative data not only for unravel the population structure and differentiation, but also for further conservation genetics studies on this balitorid species. PMID:24937572

  15. The complete mitochondrial genome of the Megalobrama pellegrini (Teleostei: Cyprinidae).

    PubMed

    Liu, Xueqing; Xiao, Kan; Zhao, Xun; Liu, Juanjuan; Zhang, Xu; Guo, Wentao; Chen, Lei; Du, Hejun

    2016-09-01

    The complete mitochondrial genome of Megalobrama pellegrini was determined by using a PCR-based sequencing method. The mitochondrial was 16,620 bp in length, including 13 protein genes, two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and one control region. All genes were encoded on the heavy strain except for ND6 and eight tRNA genes. The gene arrangement of M. pellegrini was similar to those found in the other Megalobrama species. Base composition of the heavy strain was A (31.19%), T (24.69%), C (46.37%), G (16.22%) and with A + T bias of 55.88%. PMID:25600731

  16. Mechanisms of branchial cartilage growth in Astatotilapia elegans (Teleostei: Cichlidae).

    PubMed Central

    Huysseune, A; Verraes, W; Desender, K

    1988-01-01

    The growth of the cartilaginous infrapharyngobranchial II (part of the upper pharyngeal jaws) in the cichlid fish Astatotilapia elegans was investigated in four successive early postembryonic stages. Total cell number, individual cell volumes, total cell, total matrix and total cartilage volume were accurately measured or calculated. The share of cell and matrix volume increase in the overall growth was calculated for each of the transitions. Matrix volume increase accounted for almost 60% of the overall rudiment increase. Non-hypertrophic cells and the matrix produced by them together accounted for about three quarters of the total cartilage volume increase. Zones with particular characteristics (cell orientation, cell shape, degenerative features, etc.) were distinguished in each of the four stages separately. The sequence of increasing mean cell volume between zones was interpreted as reflecting growth directions within the cartilage. Apposition probably largely contributed to the observed cell volume increase. Mean cell volume and mean matrix volume per cell showed a highly significant positive relation. Cell density showed a highly significant negative relation to both mean cell volume and mean matrix volume. Our results indicate that the area of hypertrophy and cartilage resorption may be established quite early in the rudiment before overt manifestation of these processes. Images Fig. 2 Fig. 3 Fig. 4 PMID:3225217

  17. The complete mitochondrial genome of Schizopygopsis pylzovi (Teleostei, Cyprinidae, Schizopygopsis).

    PubMed

    Lai, Jiansheng; Liu, Ya; Chen, Yeyu; Li, Hua; Du, Jun; Li, Lianman

    2016-09-01

    Schizopygopsis pylzovi, an endemic species in the Qinghai-Tibetan Plateau, has a unique ability to adapt to the extreme ecological condition of the plateau. In this study, we successfully sequenced the first mitochondrial genome of S. pylzovi. The mitogenome is 16,814 bp in length, containing 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region (D-loop). The overall base composition of the heavy strand (H-strand) is 28.3% A, 26.1% C, 18.6% G, and 27.0% T, with a slight AT bias of 55.3%. Most of the genes are encoded on H-strand, except for eight tRNAs (tRNA(Gln), tRNA(Ala), tRNA(Asn), tRNA(Cys), tRNA(Tyr), tRNA(Ser), tRNA(Glu) and tRNA(Pro)) and ND6 genes. PMID:25690050

  18. Eviota piperata, a new gobiid species from Palau (Teleostei: Gobiidae).

    PubMed

    Greenfield, David W; Winterbottom, Richard

    2014-01-01

    A new species of dwarfgoby, Eviota piperata is described from Palau. It belongs to the cephalic sensory-pore system Group II (lacking only the IT pore); has a dorsal/anal-fin formula of 8/8; has some pectoral-fin rays branched; no dark spot over the ural centrum; the male genital papilla is not fimbriate; and the cheek and body are heavily peppered with chromatophores. PMID:24869823

  19. The complete mitochondrial genome of Xenophysogobio nudicorpa (Teleostei, Cypriniformes, Cyprinidae).

    PubMed

    Zeng, Xiaoyun; Huiwu, Tian; Wang, Dengqiang; Duan, Xinbin; Chen, Daqing

    2016-05-01

    Xenophysogobio nudicorpa is a rare and endemic fish species found only in the upper Yangtze River basin in China. Here, the complete mitochondrial genome of X. nudicorpa ha been determined by polymerase chain reaction and directly sequenced with primer walking method. The genome was 16,592 bp in length and contained 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a non-coding control region (D-loop). The gene order and composition of X. nudicorpa was similar to most other vertebrates. The overall base composition of the heavy strand was 30.22% A, 27.09% T, 25.76% C and 16.93% G, with a slight AT bias of 57.31%. The complete mitogenome sequence of X. nudicorpa provides fundamental data for further conversation genetics and captive breeding studies on this species. PMID:25648926

  20. Complete mitochondrial genome of Alburnus istanbulensis (Teleostei, Cyprinidae).

    PubMed

    Eldem, Vahap; Kuban, Cneyt; Kuban, Nerdin

    2016-03-01

    Alburnus istanbulensis (Thracian shemaya) is an endemic fish species to the northwestern region of Turkey. Alburnus istanbulensis has a remarkably limited geographic distribution, and no genetic data have been available on this species until now. The mitogenome (16,612?bp) had the typical mitochondrial characteristics of other Leuciscinae fishes. This mitogenome sequence can help to further resolve phylogenetic relationships among Cyprinidae. PMID:25093400

  1. Mitochondrial genome of silver gudgeon, Squalidus argentatus (Teleostei, Cypriniformes).

    PubMed

    Zhou, Qiao; Hu, Ying-Xiong; Ye, Qin; Xue, Yang; Chen, Da-Qing; Li, Yun

    2016-01-01

    In this paper, we first determined the complete mitochondrial genome sequence of Squalidus argentatus, which was 16,607?bp in size and the whole base composition was estimated to be 30.48% A, 25.45% T, 27.36% C, 16.72% G with AT bias of 55.93%. The complete mitogenome comprised 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and 1 control region, with the gene order and content identical to other vertebrate mitogenomes. The complete mitogenome of S. argentatus provides the valuable information for population genetics and phylogeography studies on this species. PMID:24450723

  2. The complete mitochondrial genome of Polydactylus sextarius (Teleostei, Mugiliformes).

    PubMed

    Wang, Chengyi; Qiu, Jianbiao; Peng, Xin; Ai, Weiming; Huang, Xiaolin; Liu, Weicheng; Chen, Shaobo

    2016-09-01

    The complete mitogenome of Polydactylus sextarius was firstly determined in this study using a long polymerase chain reaction (PCR) method and genome walking. It is 16,836 bp in length and has 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and 1 control region. The genes composition and order of which are similar to most other vertebrates. All mitochondrial genes are encoded on the heavy strand, except for eight tRNA and ND6 genes. The overall base composition of the heavy strand is 27.4% A, 26.0% T, 29.9% C, and 16.7% G, with a slight AT bias of 53.4%. There are eight regions of gene overlap totaling 27 bp and 16 intergenic spacer regions totaling 344 bp. The mitogenome sequence of P. sextarius could contribute to the solution of its phylogenetic position within Polynemidae fishes based on the whole mitogenomic data. PMID:25714147

  3. The complete mitochondrial genome of the Epinephelus polyphekadion (Teleostei, Serranidae).

    PubMed

    Zhang, Guoqing; Chen, Mengmeng; Luo, Jian; Chen, Guohua

    2016-07-01

    In this study, the complete mitochondrial genome of the Epinephelus polyphekadion has been sequenced by the next-generation sequencing (NGS) techniques strategy. The mitochondrial genome is 16,691 bp in length and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region. The nucleotide compositions of the light strand are 27.90% A, 29.05% T, 27.48% G and 15.58% C. With the exception of ND6 and eight tRNA genes, all other mitochondrial genes are encoded on the heavy-strand (H-strand). All the tRNAs have clover secondary structure with conservative anticodon arm, TΨC arm and D arm except for tRNA-Ser(GCT) and tRNA-Pro(TGG), which D arm consists of 13 bp and 7 bp single-base, respectively. Phylogenetic tree showed that E. latifasciatus, E. polyphekadion, E. epistictus, E. akaara and E. stictus of the Epinephelus formed a monophyletic group, whereas E. latifasciatus, E. polyphekadion and E. epistictus formed a sister group. PMID:26061342

  4. The complete mitochondrial genome of the Plectorhinchus cinctus (Teleostei, Haemulidae).

    PubMed

    Liu, Li; Yang, Huirong; Zhao, Huihong; Sun, Jijia; Han, Xingpeng; Zhu, Shaoxuan; Li, Guifeng

    2016-03-01

    We present the complete mitochondrial genome of the Plectorhinchus cinctus in this study. The mitochondrial genome is 16,523 bp in length and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region. The nucleotide compositions of the light strand are 31.30% of C, 27.66% of A, 24.54% of T, and 16.50% of G. With the exception of ND6 and eight tRNA genes, all other mitochondrial genes are encoded on the heavy strand. All the protein-coding genes begin with an ATG initiation codon except for COX1 with GTG. Five types of termination codons revealed are TAA (ND1, ND2, ATP8, ND4L, ND5), T (COXП, ND3, ND4, CYTB), TA (ATP6, COXШ), AGG (COXІ) and TAG (ND6). PMID:24865922

  5. 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

  6. The complete mitochondrial genome of Hemiculterella sauvagei (Teleostei, Cyprinidae, Hemiculterella).

    PubMed

    He, Bin; Chen, Yeyu; Liu, Ya; Du, Jun; Deng, Xiaochuan

    2016-09-01

    Hemiculterella sauvagei, a Chinese minnow endemic to the upper Yangtze River, is an important part of the aquatic ecosystem and plays a vital ecological role in maintaining aquatic biodiversity. In this study, we provide the first mitochondrial genome of H. sauvagei. The complete mitochondrial genome of H. sauvagei is 16618 bp in length, containing 13 protein-coding genes, two rRNA genes (12 S and 16 S rRNA), 22 tRNA genes and a non-coding control region (D-loop). The gene nucleotide composition of H. sauvagei is A = 29.9%, T = 27.0%, C = 17.4% and G = 25.6%, with a slight AT bias of 56.9%. The complete mitochondrial genome of H. sauvagei would be useful for further studies on genetic diversity and molecular phylogenetic relationship of the subfamily Cultrinae. PMID:25693700

  7. Evolutionary origin and early biogeography of otophysan fishes (Ostariophysi: Teleostei).

    PubMed

    Chen, Wei-Jen; Lavoué, Sébastien; Mayden, Richard L

    2013-08-01

    The biogeography of the mega-diverse, freshwater, and globally distributed Otophysi has received considerable attention. This attraction largely stems from assumptions as to their ancient origin, the clade being almost exclusively freshwater, and their suitability as to explanations of trans-oceanic distributions. Despite multiple hypotheses explaining present-day distributions, problems remain, precluding more parsimonious explanations. Underlying previous hypotheses are alternative phylogenies for Otophysi, uncertainties as to temporal diversification and assumptions integral to various explanations. We reexamine the origin and early diversification of this clade based on a comprehensive time-calibrated, molecular-based phylogenetic analysis and event-based approaches for ancestral range inference of lineages. Our results do not corroborate current phylogenetic classifications of otophysans. We demonstrate Siluriformes are never sister to Gymnotiformes and Characiformes are most likely nonmonophyletic. Divergence time estimates specify a split between Cypriniformes and Characiphysi with the fragmentation of Pangea. The early diversification of characiphysans either predated, or was contemporary with, the separation of Africa and South America, and involved a combination of within- and between-continental divergence events for these lineages. The intercontinental diversification of siluroids and characoids postdated major intercontinental tectonic fragmentations (<90 Mya). Post-tectonic drift dispersal events are hypothesized to account for their current distribution patterns. PMID:23888847

  8. The complete mitochondrial genome of Alburnus tarichi (Teleostei, Cyprinidae).

    PubMed

    Kubanç, Nerdin; Eldem, Vahap; Kubanç, Cüneyt

    2016-03-01

    Alburnus tarichi is the only vertebrate species that can survive in Lake Van, the largest soda lake on Earth, which is characterized by extremely high pH and salinity. The circular mitogenomes of A. tarichi was 16,602 base pairs in size, containing 13 protein-coding genes (PCGs), 2 rRNA genes, 22 tRNA genes, and 2 major non-coding control regions (D-Loop and OL). Congurence was observed between the Alburnus mtDNAs in terms of genome organization, base composition, gene arrangement, and tRNA structure. Mitogenome sequences may be useful for conservation efforts of this endangered species. PMID:25090382

  9. 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. PMID:24730608

  10. The complete mitochondrial genome of Lepturichthys fimbriata (Teleostei, Balitoridae, Balitorinae).

    PubMed

    Xu, Dong-Mei; Yang, Zhi; Xu, Nian; Xiong, Mei-Hua; Lei, Pan; Que, Yan-Fu

    2016-03-01

    Lepturichthys fimbriata is an endemic and an important commercial fish which distributes in the upper stream of the Yangtze River. In this study, the complete mitogenome sequence of L. fimbriata has been first sequenced by DNA sequencing based on the PCR fragments. The mitogenome, consisting of 16,567 base pairs (bp), includes 13 protein coding genes, 22 transfer RNAs, 2 ribosomal RNA genes and a non-coding control region (CR). The overall base composition of L. fimbriata is 30.4% A, 28.7% C, 16.5% G, and 24.4% T, with a relatively a slight AT bias of 54.7%. CR of 903 bp length is located between tRNA(Pro) and tRNA(Phe). The complete mitochondrial genome sequence would be useful for further studies on conservation genetics and resource management in L. fimbriata. PMID:24963762

  11. 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. PMID:25806579

  12. Complete mitochondrial genome of Triplophysa robusta (Teleostei: Cypriniformes: Balitoridae).

    PubMed

    Yan, Pengfei; Li, Jiuxuan; Ma, Qingzhan; Deng, Yuanping; Song, Zhaobin

    2016-05-01

    The complete mitochondrial genome of the Triplophysa robusta has been determined in this study. It is 16,572 bp in size and consists of 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and one non-coding control region (D-loop). The overall base composition of the heavy strand of the T. robusta mitochondrial genome was A: 28.20%, T: 28.27%, C: 25.37%, and G: 18.16%. The total length of the 13 protein-coding genes was 11,428 bp. Analysis of the genes indicated the high genetic variability among Triplophysa species. PMID:25238109

  13. The complete mitochondrial gemone of Phoxinus lagowskii (Teleostei, Cypriniformes: Cyprinidae).

    PubMed

    Sun, Qinliang; Wang, Dengqiang; Wei, Qiwei

    2016-03-01

    In this paper, we determined the whole mitochondrial DNA (mtDNA) sequence of Phoxinus lagowskii, a small freshwater fish that is distributed in rivers of north China, Russia and North Korea. The entire sequence of P. lagowskii mitochondrial genome is 16,699 bp in size, consisting of 13 protein-coding genes, 2 ribosomal RNA genes (12S rRNA and 16S rRNA), 22 transfer RNA genes (tRNA) and 1 putative control region. Most of the genes are encoded on the heavy strand except ND6 and eight tRNA genes (Gln, Ala, Asn, Cys, Try, Ser, Glu and Pro) encoded on the light strand. PMID:24865913

  14. A new species of Ptychochromis from southeastern Madagascar (Teleostei: Cichlidae).

    PubMed

    Martinez, Christopher M; Arroyave, Jairo; Sparks, John S

    2015-01-01

    We describe a new species in the endemic Malagasy cichlid genus Ptychochromis. Ptychochromis mainty, new species, is known from four individuals, all collected in the Fort Dauphin region of southeastern Madagascar, and shares a palatine morphology (eastern-type palatine) with other eastern congeners. Ptychochromis mainty is distinguished from all congeners by a nearly uniform dark brown to black pigmentation pattern in preservation and by the presence of a relatively continuous and expansive black longitudinal midlateral blotch in life, extending from the posterior margin of the opercle to the caudal peduncle. The new species is further distinguished from other eastern Ptychochromis species by having minimal or no overlap of the first supraneural with the dorsoposterior region of the supraoccipital crest (vs. marked overlap). We present a molecular-based phylogeny for all available Ptychochromis species, which supports the hypothesis that P. mainty is a distinct taxon. The new species is recovered as the sister taxon to P. grandidieri within a clade comprising species with an eastern-type palatine morphology. We present a geometric morphometric analysis that provides additional evidence to distinguish P. mainty from congeners. PMID:26624703

  15. The complete mitochondrial genome of Liobagrus marginatus (Teleostei, Siluriformes: Amblycipitidae).

    PubMed

    Li, Qiang; Du, Jun; Liu, Ya; Zhou, Jian; Ke, Hongyu; Liu, Chao; Liu, Guangxun

    2014-04-01

    The Liobagrus marginatus is an economic fish which distribute in the upstream of Yangtze river and its distributary. For its taste fresh, environmental pollution and overfishing, its population declined drastically and body miniaturization in recent decades, so it is essential to protect its resource. In this study, the complete mitochondrial genome sequence of Liobagrus marginatus was sequenced, which contains 22 tRNA genes, 13 protein-coding genes, 2 rRNA genes, and a non-coding control region with the total length of 16,497 bp. The gene arrangement and composition are similar to most of other fish. Most of the genes are encoded on heavy-strand, except for eight tRNA and ND6 genes. Just like most other vertebrates, the bias of G and C has been found in statistics results of different genes/regions. The complete mitochondrial genome sequence of Liobagrus marginatus would contribute to better understand population genetics, evolution of this lineage, and will help administrative departments to make rules and laws to protect it. PMID:23795826

  16. Complete mitochondrial genome of Gymnodiptychus pachycheilus (Teleostei: Cypriniformes: Cyprinidae).

    PubMed

    Wu, Bo; Deng, Yuanping; Wu, Jiayun; Yan, Chaochao; Song, Zhaobin

    2016-01-01

    The complete mitochondrial DNA genome of Gymnodiptychus pachycheilus was sequenced and characterized. The genome is 16,586 bp in length. As with most teleosts, the mitogenome of G. pachycheilus is structurally conserved, containing two ribosomal RNA (rRNA) genes, 13 protein-coding genes, 22 transfer RNA (tRNA) genes and one displacement loop (D-loop) region. The 12 heavy-strand protein-coding genes of G. pachycheilus and other 15 Schizothoracinae species were used for phylogenetic analysis by Bayesian inference and maximum likelihood methods. The topology demonstrated that G. pachycheilus is relatively close to species in genera of Gymnocypris, Schizopygopsis and Oxygymnocypris but differentiated earlier in Schizothoracinae than them. PMID:24521493

  17. The complete mitochondrial genome of Gymnodiptychus pachycheilus (Teleostei, Cyprinidae, Schizothoracinae).

    PubMed

    Chen, Chunna; Li, Hua; Huang, Yingying; Gong, Quan; Du, Jun

    2016-01-01

    Gymnodiptychus pachycheilus, an endangered cold-water fish belonging to the specialized schizothoracins, is distributed in plateau lakes and the upper reaches of the Yellow and Yangtze Rivers on the northeastern Qinghai-Tibet Plateau in China. In this study, we determined the complete mitogenome sequence of G. pachycheilus. Its complete mitochondrial genome is 16,675 bp in size, and includes 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 control region, which has identical genomic organization and structure to other vertebrates, with the exception of 86 bp non-coding region between tRNA(Thr) and tRNA(Pro). This new complete mitogenome could provide useful data for further studies on stock evaluation and conservation genetics of this species. PMID:24617490

  18. The complete mitochondrial genome of the Culter recurviceps (Teleostei, Cyprinidae).

    PubMed

    Yang, Huirong; Zhao, Huihong; Sun, Jijia; Xie, Zhenzhen; Yang, Zituo; Liu, Li

    2016-01-01

    We present the complete mitochondrial genome of the Culter recurviceps in this study. The mitochondrial genome is 16,622 bp long and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region. The gene order and composition of C. recurviceps mitochondrial genome was similar to that of most other vertebrates. The nucleotide compositions of the light strand are 31.36% of A, 24.77% of T, 27.77% of C and 16.09% of G. With the exception of ND6 and eight tRNA genes, all other mitochondrial genes are encoded on the heavy strand. Two copies of tandem repeat sequence (24 bp) was observed in the end of the 123 bp in control region. PMID:24810061

  19. Source and trophic transfer of mercury in plankton from an ultraoligotrophic lacustrine system (Lake Nahuel Huapi, North Patagonia).

    PubMed

    Rizzo, Andrea; Arcagni, Marina; Campbell, Linda; Koron, Neža; Pavlin, Majda; Arribére, María A; Horvat, Milena; Guevara, Sergio Ribeiro

    2014-09-01

    The incorporation and trophic transfer of total and methyl mercury (THg, MeHg) were examined in three size classes of plankton (10-53, 53-200, and >200 μm size range) and a small planktivorous fish, Galaxias maculatus, from the large multi-branched Lake Nahuel Huapi (North Patagonia, Argentina). Three sites representing a large range of lake benthic-pelagic structures (based on depth and shoreline characteristics) and precipitation regimes were sampled. Nitrogen and carbon stable isotopes (δ(15)N, δ(13)C) were analyzed to assess Hg trophodynamics. Selenium concentrations were determined together with THg in order to consider its potential effect on Hg trophodynamics. High THg concentrations (0.1-255 µg g(-1) dry weight (DW)) were measured in plankton, largely in inorganic form (MeHg: 3-29 ng g(-1) DW, 0.02-7% of THg, in the two larger size classes). A trend of increasing THg concentrations, varying in two to three orders of magnitude, with decreasing plankton size was associated with precipitation measured prior to each sampling event. Passive adsorption of dissolved Hg(2+) from wet deposition and runoff is considered to be the principal Hg uptake mechanism at the base of the pelagic food web. Despite the initially high THg uptake in the smaller plankton classes, the transfer to G. maculatus, and consequently to the entire food web, is likely limited due to low proportion of MeHg to THg in plankton. Furthermore, evidence of G. maculatus with benthic feeding habits having higher impact on MeHg trophic transfer compared to the same species with more pelagic (e.g., zooplankton) feeding habits, was observed. Although there is a high THg uptake in plankton, limited amounts are incorporated in the entire food web from the pelagic compartment. PMID:24844168

  20. [Parasitism in fishes and human riverside communities of the Huillinco and Natri lakes (Great Island of Chiloé), Chile].

    PubMed

    Torres, P; Ruíz, E; Rebolledo, C; Mira, A; Cubillos, V; Navarrete, N; Gesche, W; Montefusco, A; Valdés, L; Alberdi, A

    1990-01-01

    In April and December 1989, 35 fish from Lake Huillinco (42 degrees 48'S, 74 degrees 02'W) and 36 fish from Lake Natri (42 degrees 48'S, 73 degrees 50'W), in the Great Island of Chiloé (Chile) were examined. Coprological samples from 159 persons, 17 dogs, 19 pigs and 4 cats from around both lakes were examined for Diphyllobothrium spp. infection. In the Lake Huillinco the following helminths of fishes were determined: Contracaecum sp. and Hysterothylacium sp. in Salmo trutta, Cauque mauleanum and Eleginops maclovinus; Dichelyne (Cucullanellus) dichelyneformis in S. trutta and E. maclovinus and Scolex pleuronectis in S. trutta. One specimen of Mugil cephalus did not show helminth parasites. Prevalence of infection were greater for Contracaecum sp. in S. trutta (75.0%) and C. mauleanum (76.0%); and Hysterothylacium sp. in E. maclovinus (75.0%). Mean intensity was higher for D. (C.) dichelyneformis in E. maclovinus. Contracaecum sp. in S. trutta, Oncorhynchus mykiss, Oncorhynchus kisutch and Galaxias maculatus; Acanthocephalus sp. in S. trutta and G. maculatus, S. pleuronectis in O. mykiss and Cystidicoloides sp. in G. maculatus were determined at Lake Natri. Prevalence and intensity of infection were higher for Contracaecum sp. in S. trutta and O. kisutch. Infection by Diphyllobothrium sp. was determined in one domestic cat. Prevalence of infection by intestinal protozoan and helminths in human population only showed significative differences for Ascaris lumbricoides and Trichuris trichiura that were higher in the Lake Huillinco. Importance of natural infection by helminth parasites for fish in cultured condition and possible mechanisms of infections in relation to the diet of fishes are discussed. PMID:2152358

  1. Bioefficacy of some plant derivatives that protect grain against the pulse beetle, Callosobruchus maculatus

    PubMed Central

    Rahman, A.; Talukder, F. A.

    2006-01-01

    Experiments were conducted to study the bioefficacies of different plant/weed derivatives that affect the development of the pulse beetle, Callosobruchus maculates F. (Coleoptera: Bruchidae) fed on black gram, Vigna mungo, seeds. Plant extracts, powder, ash and oil from nishinda (Vitex negundo L.), eucalyptus (Eucalyptus globules Labill.), bankalmi (Ipomoea sepiaria K.), neem (Azadirachta indica L.), safflower (Carthamus tinctorius L.), sesame (Sesamum indicum L.) and bablah (Acacia arabica L.) were evaluated for their oviposition inhibition, surface protectant, residual toxicity and direct toxicity effects on C. maculates. The results showed that plant oils were effective in checking insect infestation. The least number of F1 adults emerged from black gram seeds treated with neem oil. The nishinda oil extract was the most toxic of three extracts tested (nishinda, eucalyptus and bankalmi). Bablah ash was the most effective compared to the powdered leaves of nishinda, eucalyptus and bankalmi. The powdered leaves and extracts of nishinda, eucalyptus and bankalmi, at a 3% mixture, provided good protection for black gram seeds by reducing insect oviposition, F1 adult emergence, and grain infestation rates. The oil treatment did not show adverse effects on germination capability of seeds, even after three months of treatment. PMID:19537990

  2. Fine structure of a freshwater teleost (Pimelodus maculatus) intrahepatic biliary pathways.

    PubMed

    Ferri, S

    1982-01-01

    The intrahepatic biliary passages of a teleost liver composed by a muralium duplex was studied by electron microscopy. The bile canaliculus was commonly formed by 2 or more hepatic cells. In the transition zone between the intercellular bile canaliculus and the bile ductule, this duct was formed in part by hepatic cells and in part by duct cells. While the number of duct cells increased, the number of hepatocytes decreased until the entire ductule was formed by 2 or 3 duct cells. Bile duct was formed only by pyramidal duct cells. These cells are readily distinguished from the hepatocytes by its irregular shape, by a paucity of organelles and by the abundance of microfilaments. PMID:7201253

  3. Eugregarines reduce susceptibility of the hide beetle, Dermestes maculatus, to apicomplexan pathogens and retard larval development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eugregarines are abundant in a great diversity of invertebrates, and yet their relationships with their hosts are subject to controversy and confusion. We tested the effect of the eugregarine, Pyxinia crystalligera, on growth, development, and susceptibility to two Apicomplexa pathogens of the hide ...

  4. Particle Swarm Optimization (PSO) en modelos semi-analíticos de formación de galaxias

    NASA Astrophysics Data System (ADS)

    Ruiz, A. N.; Domínguez, M. J.; Padilla, N. D.; Cora, S. A.; García Lambas, D.; Tecce, T. E.; Gargiulo, I. D.; Muñoz Arancibia, A. M.

    We present preliminary results of calibrations of a semi-analytic galaxy formation model performed using the Particle Swarm Optimization (PSO) technique. This method involves the exploration of the parameter space by random walks of a set of ``particles'' that share information between them. Thus, comparing the model results against a set of observables (e.g. luminosity functions, the relation between black hole mass and bulge mass, morphological fractions), the PSO method yields a set of best-fitting values for the free parameters of the model. FULL TEXT IN SPANISH

  5. Sistemas de Cúmulos Globulares: trazando la formación y evolución de las galaxias

    NASA Astrophysics Data System (ADS)

    Faifer, F. R.

    In this paper; we review some properties and mentioned several aspects that have caused a marked and renewed interest in the study of globular cluster systems in the last decade. We emphasised on the relationship between some of these properties and galaxies formation processes. FULL TEXT IN SPANISH

  6. Relaciones fundamentales de la población de galaxias de tipo temprano del cúmulo de Antlia

    NASA Astrophysics Data System (ADS)

    Calderón, J. P.; Bassino, L. P.; Cellone, S. A.; Smith Castelli, A. V.; Caso, J. P.

    We present the results of a study of more than 100 early-type galaxies in Antlia Cluster, that span from giant ellipticals to dwarf ellipticals, covering a magnitude range of 11 magnitudes (M_{V_T} = -22 to -11). We perform surface photometry of these galaxies, and their total magnitudes, surface brightnesses and radii are determined on the basis of the Sérsic law fits. Finally, the fundamental relations between them are analyzed. FULL TEXT IN SPANISH

  7. Molecular phylogeny and phylogeography of the Australian freshwater fish genus Galaxiella, with an emphasis on dwarf galaxias (G. pusilla).

    PubMed

    Unmack, Peter J; Bagley, Justin C; Adams, Mark; Hammer, Michael P; Johnson, Jerald B

    2012-01-01

    The freshwater fauna of Southern Australia is primarily restricted to the southwestern and southeastern corners of the continent, and is separated by a large, arid region that is inhospitable to this biota. This geographic phenomenon has attracted considerable interest from biogeographers looking to explain evolutionary diversification in this region. Here, we employed phylogenetic and phylogeographic approaches to evaluate the effect of this barrier on a group of four galaxiid fish species (Galaxiella) endemic to temperate Southern Australia. We also tested if continental shelf width has influenced connectivity among populations during low sea levels when rivers, now isolated, could have been connected. We addressed these questions by sampling each species across its range using multiple molecular markers (mitochondrial cytochrome b sequences, nuclear S7 intron sequences, and 49 allozyme loci). These data also allowed us to assess species boundaries, to refine phylogenetic affinities, and to estimate species ages. Interestingly, we found compelling evidence for cryptic species in G. pusilla, manifesting as allopatric eastern and western taxa. Our combined phylogeny and dating analysis point to an origin for the genus dating to the early Cenozoic, with three of the four species originating during the Oligocene-Miocene. Each Galaxiella species showed high levels of genetic divergences between all but the most proximate populations. Despite extensive drainage connections during recent low sea levels in southeastern Australia, populations of both species within G. pusilla maintained high levels of genetic structure. All populations experienced Late Pleistocene-Holocene population growth, possibly in response to the relaxation of arid conditions after the last glacial maximum. High levels of genetic divergence and the discovery of new cryptic species have important implications for the conservation of this already threatened group of freshwater species. PMID:22693638

  8. Molecular Phylogeny and Phylogeography of the Australian Freshwater Fish Genus Galaxiella, with an Emphasis on Dwarf Galaxias (G. pusilla)

    PubMed Central

    Unmack, Peter J.; Bagley, Justin C.; Adams, Mark; Hammer, Michael P.; Johnson, Jerald B.

    2012-01-01

    The freshwater fauna of Southern Australia is primarily restricted to the southwestern and southeastern corners of the continent, and is separated by a large, arid region that is inhospitable to this biota. This geographic phenomenon has attracted considerable interest from biogeographers looking to explain evolutionary diversification in this region. Here, we employed phylogenetic and phylogeographic approaches to evaluate the effect of this barrier on a group of four galaxiid fish species (Galaxiella) endemic to temperate Southern Australia. We also tested if continental shelf width has influenced connectivity among populations during low sea levels when rivers, now isolated, could have been connected. We addressed these questions by sampling each species across its range using multiple molecular markers (mitochondrial cytochrome b sequences, nuclear S7 intron sequences, and 49 allozyme loci). These data also allowed us to assess species boundaries, to refine phylogenetic affinities, and to estimate species ages. Interestingly, we found compelling evidence for cryptic species in G. pusilla, manifesting as allopatric eastern and western taxa. Our combined phylogeny and dating analysis point to an origin for the genus dating to the early Cenozoic, with three of the four species originating during the Oligocene-Miocene. Each Galaxiella species showed high levels of genetic divergences between all but the most proximate populations. Despite extensive drainage connections during recent low sea levels in southeastern Australia, populations of both species within G. pusilla maintained high levels of genetic structure. All populations experienced Late Pleistocene-Holocene population growth, possibly in response to the relaxation of arid conditions after the last glacial maximum. High levels of genetic divergence and the discovery of new cryptic species have important implications for the conservation of this already threatened group of freshwater species. PMID:22693638

  9. Propiedades estadísticas de galaxias en las futuras estructuras más grandes del universo

    NASA Astrophysics Data System (ADS)

    Lares, M.; Yaryura, Y.; García Lambas, D.

    Superclusters of galaxies are the largest isolated structures in the universe. We study statistical properties of clustering of galaxies within superclus- ters, using a catalogue calibrated to identify future bound superstructures. We use a volume limited sample (z < 0.1) of spectroscopic galaxies from SDSS-DR7 to select luminous galaxies as centers, and fainter galaxies as tracers, to compute the cross­correlation function of galaxies. We find that this function depends on the chosen centers: luminous galaxies in super- clusters show a higher cross­correlation with tracers. We define subsamples to obtain an unbiased estimation of the clustering, independent of luminos- ity and mass. The influence of large scale environment is seen for galaxies in SCG only for distances greater than ~ 1Mpc. FULL TEXT IN SPANISH

  10. Origen y evolución de la relación de Tully-Fisher en galaxias simuladas

    NASA Astrophysics Data System (ADS)

    Ferrero, I.; Abadi, M. G.; Algorry, D. G.

    2015-08-01

    Using the hydrodynamic cosmological simulations of galaxy formation Gimic (Galaxies Intergalactic Medium-Interaction Calculation) we study the origin and the evolution of the Tully-Fisher relation in comparison with same observational results for different redshifts ranging from z = 0 to z = 2. Preliminary results indicate the possible existence of a conspiracy between the amounts of dark matter and baryons (stars and gas) in the central parts of galaxies which is fundamental to establishing this correlation.

  11. Criterios de Identificación de Supercáscaras de Hidrógeno Neutro en Nuestra Galaxia.

    NASA Astrophysics Data System (ADS)

    Suad, L. A.; Arnal, E. M.

    Using the all-sky neutral hydrogen (HI) survey of Kalberla et al. (2005), together with new criteria and techniques (both visual and digital) a new catalogue of galactic HI supershells will be produced in order to complement the existing ones (Heiles 1979, McClure-Griffiths et al. 2002). In this poster our identification criteria are applied to an existing galactic HI supershell (GS095+04-113) previously identified by Heiles (1979) as a "well established" case. Our criteria seems to indicate that this huge structure may be understood in terms of two smaller HI shells interacting with each other. FULL TEXT IN SPANISH

  12. Cinemática y masas de agujeros negros en galaxias activas del tipo "Narrow Line Seyfert 1"

    NASA Astrophysics Data System (ADS)

    Oío, G.; Schmidt, E.; Vega Neme, L. R.

    We apply a spectral synthesis method to Narrow Line Seyfert 1 active galax- ies with public spectra available. Our goal will be to obtain the stellar ve- locity dispersions, and then the central black hole masses via the Tremaine relation. We comment several problems we found in fitting this type of objects and the possibility of obtaining masses through the emission lines. FULL TEXT IN SPANISH

  13. Diferenciación de Galaxias Activas de Líneas Delgadas a Partir de Diagramas BPT

    NASA Astrophysics Data System (ADS)

    Torres, J.; Portilla, J. G.

    Classification of active galaxies is made through careful analysis of their spectra, either by measuring the width of the emission lines or comparing the flux ratios between these lines. One of the best known methods for this process is the use of BPT (Baldwin, Phillips, & Terlevich) diagrams which allow the distinction of different types of active galaxies. In this article we present the study of a sample of active galaxies with thin lines taken from the SDSS (Sloan Digital Sky Survey) whose flux ratios were measured and diagnostic diagrams were constructed, thus allowing the differentiation between starburst (or H II) galaxies and authentic type 2 active galactic nuclei (AGNs). We show that there are some objects with similar spectra that have been misclassified. FULL TEXT IN SPANISH

  14. Constraints upon the Response of Fish and Crayfish to Environmental Flow Releases in a Regulated Headwater Stream Network

    PubMed Central

    Chester, Edwin T.; Matthews, Ty G.; Howson, Travis J.; Johnston, Kerrylyn; Mackie, Jonathon K.; Strachan, Scott R.; Robson, Belinda J.

    2014-01-01

    In dry climate zones, headwater streams are often regulated for water extraction causing intermittency in perennial streams and prolonged drying in intermittent streams. Regulation thereby reduces aquatic habitat downstream of weirs that also form barriers to migration by stream fauna. Environmental flow releases may restore streamflow in rivers, but are rarely applied to headwaters. We sampled fish and crayfish in four regulated headwater streams before and after the release of summer-autumn environmental flows, and in four nearby unregulated streams, to determine whether their abundances increased in response to flow releases. Historical data of fish and crayfish occurrence spanning a 30 year period was compared with contemporary data (electrofishing surveys, Victoria Range, Australia; summer 2008 to summer 2010) to assess the longer–term effects of regulation and drought. Although fish were recorded in regulated streams before 1996, they were not recorded in the present study upstream or downstream of weirs despite recent flow releases. Crayfish (Geocharax sp. nov. 1) remained in the regulated streams throughout the study, but did not become more abundant in response to flow releases. In contrast, native fish (Gadopsis marmoratus, Galaxias oliros, Galaxias maculatus) and crayfish remained present in unregulated streams, despite prolonged drought conditions during 2006–2010, and the assemblages of each of these streams remained essentially unchanged over the 30 year period. Flow release volumes may have been too small or have operated for an insufficient time to allow fish to recolonise regulated streams. Barriers to dispersal may also be preventing recolonisation. Indefinite continuation of annual flow releases, that prevent the unnatural cessation of flow caused by weirs, may eventually facilitate upstream movement of fish and crayfish in regulated channels; but other human–made dispersal barriers downstream need to be identified and ameliorated, to allow native fish to fulfil their life cycles in these headwater streams. PMID:24647407

  15. Constraints upon the response of fish and crayfish to environmental flow releases in a regulated headwater stream network.

    PubMed

    Chester, Edwin T; Matthews, Ty G; Howson, Travis J; Johnston, Kerrylyn; Mackie, Jonathon K; Strachan, Scott R; Robson, Belinda J

    2014-01-01

    In dry climate zones, headwater streams are often regulated for water extraction causing intermittency in perennial streams and prolonged drying in intermittent streams. Regulation thereby reduces aquatic habitat downstream of weirs that also form barriers to migration by stream fauna. Environmental flow releases may restore streamflow in rivers, but are rarely applied to headwaters. We sampled fish and crayfish in four regulated headwater streams before and after the release of summer-autumn environmental flows, and in four nearby unregulated streams, to determine whether their abundances increased in response to flow releases. Historical data of fish and crayfish occurrence spanning a 30 year period was compared with contemporary data (electrofishing surveys, Victoria Range, Australia; summer 2008 to summer 2010) to assess the longer-term effects of regulation and drought. Although fish were recorded in regulated streams before 1996, they were not recorded in the present study upstream or downstream of weirs despite recent flow releases. Crayfish (Geocharax sp. nov. 1) remained in the regulated streams throughout the study, but did not become more abundant in response to flow releases. In contrast, native fish (Gadopsis marmoratus, Galaxias oliros, Galaxias maculatus) and crayfish remained present in unregulated streams, despite prolonged drought conditions during 2006-2010, and the assemblages of each of these streams remained essentially unchanged over the 30 year period. Flow release volumes may have been too small or have operated for an insufficient time to allow fish to recolonise regulated streams. Barriers to dispersal may also be preventing recolonisation. Indefinite continuation of annual flow releases, that prevent the unnatural cessation of flow caused by weirs, may eventually facilitate upstream movement of fish and crayfish in regulated channels; but other human-made dispersal barriers downstream need to be identified and ameliorated, to allow native fish to fulfil their life cycles in these headwater streams. PMID:24647407

  16. Integrating multiple bioassays to detect and assess impacts of sublethal exposure to metal mixtures in an estuarine fish.

    PubMed

    Barbee, Nicole C; Ganio, Katherine; Swearer, Stephen E

    2014-07-01

    Estuaries are natural sinks for a wide range of urban, industrial and agricultural contaminants that accumulate at potentially toxic but non-lethal concentrations, yet we know relatively little about the long-term impacts of toxicants at these levels on aquatic organisms. In this study, we present an integrated, multi-pronged approach to detect and assess the impacts to estuarine fish of exposure to sublethal concentrations of metal mixtures. Our aims were to (1) examine the effects of sublethal metal exposure on the embryonic development of Galaxias maculatus, an estuarine spawning fish native to southeastern Australia, (2) determine whether sublethal exposure during development has knock-on effects on larval behaviour, and (3) establish whether a signature of metal exposure during embryogenesis can be detected in larval otoliths ("ear bones"). G. maculatus eggs are fertilised in water but develop aerially, in direct contact with estuarine sediments. We were thus also able to explore the relative importance of two exposure pathways, water and sediment. Embryos were exposed to two concentrations of a metal mixture containing Cu, Zn and Pb in water (during fertilisation) and on spiked sediments (during development), using a fully crossed experimental design. Overall, we found that exposure to the metal mixture reduced embryo survival and slowed embryonic development, resulting in poorer quality larvae that exhibited a reduced phototactic response. Differences in exposure to metals between treatment and control embryos were also permanently recorded in the developing otoliths. Combined these three approaches have the potential to be a powerful novel bioassessment tool as they provide a means of identifying a history of metal exposure during the embryonic period and linking it to suboptimal early growth and performance traits which could have long term fitness consequences. PMID:24794343

  17. Physiological and biochemical strategies for withstanding emersion in two galaxiid fishes.

    PubMed

    Urbina, Mauricio A; Walsh, Patrick J; Hill, Jonathan V; Glover, Chris N

    2014-10-01

    The galaxiid fishes of the Southern hemisphere display variable tolerance to aerial exposure. Brown mudfish (Neochanna apoda), for example, pseudoaestivate, inhabiting moist soil for months at a time, whereas inanga (Galaxias maculatus) emerse under unfavourable water conditions, but only for periods of a few hours. This study sought to identify the physiological and biochemical strategies that determine emersion tolerance in these species. Nitrogenous waste excretion was measured before and after an experimental emersion period (14 days for mudfish, 6 h for inanga). Both species showed significantly elevated ammonia "washout" upon return to water, but no increase in plasma or muscle ammonia. Post-emersion urea levels were elevated in plasma and muscle in both fish, however the extent of the accumulation did not indicate significant de novo urea production. This was supported by the lack of carbamoyl phosphate synthetase activity in tissues. Consequently, mudfish metabolism was examined to determine whether changes in parameters such as oxygen consumption, carbon dioxide excretion, and/or altered metabolic costs (represented by the key ionoregulatory enzyme Na(+), K(+)-ATPase; NKA) could explain emersion tolerance. Oxygen consumption rates, already very low in immersed mudfish, were largely maintained over the course of emersion. Carbon dioxide excretion decreased during emersion, and a small, but significant, decrease in NKA was noted. These data suggest that the extended emersion capacity of mudfish may result from a generally low metabolic rate that is maintained throughout aerial exposure via cutaneous gas exchange, and which limits the production of potentially toxic nitrogenous waste. PMID:25026541

  18. New evidence on a cold case: trophic transmission, distribution and host-specificity in Hedruris spinigera (Nematoda: Hedruridae).

    PubMed

    Luque, José L; Vieira, Fabiano M; Herrmann, Kristin; King, Tania M; Poulin, Robert; Lagrue, Clément

    2010-09-01

    The life cycle of Hedruris spinigera Baylis, 1931 (Nematoda: Hedruridae) is determined here with the first formal identification of the parasite's intermediate host: the crustacean amphipod Paracorophium excavatum Thomson. Adult H. spinigera are redescribed from specimens collected from the stomach of fishes, Retropinna retropinna (Richardson) and Aldrichettaforsteri (Valenciennes), from Lake Waihola, New Zealand. Immature adults of the parasite collected from intermediate hosts (P. excavatum) are also described for the first time. The prevalence, abundance and intensity of infection of H. spinigera in several fish species are quantified along with the occurrence of P. excavatum, the parasite's intermediate host, in fish stomach contents. Although H. spinigera's transmission mode (trophic transmission) and fish diet potentially expose all fish species to infection, some level of host specificity must exist as parasite prevalence, abundance and intensity of infection vary greatly between potential definitive host species. We suggest here that the anatomy of the fish digestive tract and especially that of the stomach plays an important role in host suitability for H. spinigera. While P. excavatum is the only intermediate host in Lake Waihola, H. spinigera was found in six different fish species: Aldrichetta forsteri, Galaxias maculatus (Jenyns), Retropinna retropinna, Rhombosolea retiaria Hutton, Perca fluviatilis Linnaeus and Salmo trutta Linnaeus; although typical hedrurid attachment and mating positions were observed only in R. retropinna and A. forsteri. The limited distribution of H. spinigera is most likely due to that of its different host species (intermediate and definitive), all inhabitants of coastal fresh and brackish waters. PMID:20941914

  19. Leap of faith: voluntary emersion behaviour and physiological adaptations to aerial exposure in a non-aestivating freshwater fish in response to aquatic hypoxia.

    PubMed

    Urbina, Mauricio A; Forster, Malcolm E; Glover, Chris N

    2011-05-01

    Lowland stream fauna in areas of intensive agriculture are increasingly under threat from anthropogenic activities leading to eutrophication and subsequent hypoxia. Survival of hypoxic episodes depends upon a combination of behavioural and physiological adaptations. Responses of inanga (Galaxias maculatus: Galaxiidae) to aquatic hypoxia were investigated in the laboratory. Contrary to expectation inanga did not display behaviour that might reduce energy expenditure during oxygen limitation, with swimming activity slightly, but significantly elevated relative to normoxia. Instead, as dissolved oxygen concentrations decreased, the fish moved higher in the water column, increased their swimming speed and exhibited aquatic surface respiration. Physiological changes such as enhanced opercular frequency were also noted. As hypoxia deepened inanga started to leap out of the water, emersing themselves on a floating platform. Once emersed, fish exhibited an enhanced oxygen consumption rate compared to hypoxic fish. Thus inanga appear better adapted to escape hypoxia (a behavioural adaptation) rather than tolerate it (physiological adaptation). The emersion strategy used for inanga in response to severe hypoxia is in agreement with their ability to take up more oxygen from the air than from hypoxic water and therefore may justify the potentially increased risks of desiccation and predation associated with leaving the water. PMID:21316378

  20. Is the habitation of acidic-water sanctuaries by galaxiid fish facilitated by natural organic matter modification of sodium metabolism?

    PubMed

    Glover, Chris N; Donovan, Katherine A; Hill, Jonathan V

    2012-01-01

    Acidic waters of New Zealand's West Coast are hypothesized to be a refuge for native galaxiid fish, allowing them to escape predation from acid-sensitive invasive salmonid species. To determine the mechanisms by which galaxiids tolerate low pH, we investigated sodium metabolism in inanga Galaxias maculatus in response to water pH, short-term acclimation to acidic waters, the presence and source of natural organic matter (NOM), and fish life history. Contrary to expectation, inanga were physiologically sensitive to acid exposure, displaying inhibited sodium influx and exacerbated sodium efflux. Short-term (144 h) acclimation to acid did not modify this effect, and NOM did not exert a protective effect on sodium metabolism at low pH. Inanga sourced from naturally acidic West Coast waters did, however, display a sodium influx capacity (J(max)) that was significantly elevated when compared with that of fish collected from neutral waters. All inanga, independent of source, exhibited exceptionally high sodium uptake affinities (18-40 μM) relative to previously studied freshwater teleosts. Although inanga displayed relatively poor physiological tolerance to acidic waters, their high sodium influx affinity coupled with their occupation of near-coastal waters with elevated sodium levels may permit habitation of low-pH freshwaters. PMID:22902374

  1. Antagonistic Regulation, Yet Synergistic Defense: Effect of Bergapten and Protease Inhibitor on Development of Cowpea Bruchid Callosobruchus maculatus

    PubMed Central

    Sun, Yucheng; Chi, Yong Hun; Ge, Feng; Patil, Bhimanagouda S.; Koiwa, Hisashi; Zeng, Rensen; Zhu-Salzman, Keyan

    2012-01-01

    The furanocoumarin compound bergapten is a plant secondary metabolite that has anti-insect function. When incorporated into artificial diet, it retarded cowpea bruchid development, decreased fecundity, and caused mortality at a sufficient dose. cDNA microarray analysis indicated that cowpea bruchid altered expression of 543 midgut genes in response to dietary bergapten. Among these bergapten-regulated genes, 225 have known functions; for instance, those encoding proteins related to nutrient transport and metabolism, development, detoxification, defense and various cellular functions. Such differential gene regulation presumably facilitates the bruchids' countering the negative effect of dietary bergapten. Many genes did not have homology (E-value cutoff 10−6) with known genes in a BlastX search (206), or had homology only with genes of unknown function (112). Interestingly, when compared with the transcriptomic profile of cowpea bruchids treated with dietary soybean cysteine protease inhibitor N (scN), 195 out of 200 coregulated midgut genes are oppositely regulated by the two compounds. Simultaneous administration of bergapten and scN attenuated magnitude of change in selected oppositely-regulated genes, as well as led to synergistic delay in insect development. Therefore, targeting insect vulnerable sites that may compromise each other's counter-defensive response has the potential to increase the efficacy of the anti-insect molecules. PMID:22927917

  2. Combined effect of three insect growth regulators on the digestive enzymatic profiles of Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Khatter, Najat Aly; Abuldahb, Faten Farid

    2011-12-01

    Insect growth regulators (IGRs) are insecticides that mimic insect produced hormones by regulatingdevelopmental process. Theyhave little or no mammalian toxicity, and are considered reduced-risk insecticides that are often exempt from tolerance requirements of regulatory agencies. IGRs, especially, chlorfluazuron, hydroprene and hexaflumuron (benzoylphenylurea) are currently studied because of possibility of using in stored products protection. Many of IGRs compounds usedin insect pests control are known to affect digestive enzymes. Chlorfluazuron, hydroprene and hexaflumuronwere tested topically at doses of 0.25%, 0.5%&1% for chlorfluazuron and hydroprene and 0.5, 1 & 2 microg/ml of hexaflumuron to investigate its effects on the activities of the digestive enzymes protease, amylase and lipase in Callosobruchusmaculatus larvae, which were affected by IGRs individually and in combination. When combined, the effect was more sever at low concentration. There were statistically significant differences (P < or = 0.05) in enzyme activities in combined and individual treatments. Combination three IGRs caused a two-fold decrease in enzyme activity even at reduced concentration. Clear dose-response relationships were established with respect to enzyme activity. A synergistic effect of IGRs was found by combination of low doses. These effects are most pronounced in early instars. PMID:22435168

  3. Fine structure and intercellular junctions of a freshwater teleost (Pimelodus maculatus) hepatocytes by freeze-fracture replicas.

    PubMed

    Ferri, S; de Brito-Ingles Bonates, A

    1981-01-01

    The Pt-C replicas of a freshwater teleost hepatic cells were studied by electron microscopy. The surface of hepatocytes bordering the perisinusoidal space is studied with numerous microvilli. Cell-to-cell attachments are made through gap junctions and spot desmosomes. Tight junctions are found between hepatocytes close to the bile canaliculi. Some of the numerous corpuscular elements found in the cytoplasm can be identified as organelles, specially if their interiors are partially exposed by cleaving. PMID:7250650

  4. Gap Junctions Contribute to the Regulation of Walking-Like Activity in the Adult Mudpuppy (Necturus Maculatus)

    PubMed Central

    Lavrov, Igor; Fox, Lyle; Shen, Jun; Han, Yingchun; Cheng, Jianguo

    2016-01-01

    Although gap junctions are widely expressed in the developing central nervous system, the role of electrical coupling of neurons and glial cells via gap junctions in the spinal cord in adults is largely unknown. We investigated whether gap junctions are expressed in the mature spinal cord of the mudpuppy and tested the effects of applying gap junction blocker on the walking-like activity induced by NMDA or glutamate in an in vitro mudpuppy preparation. We found that glial and neural cells in the mudpuppy spinal cord expressed different types of connexins that include connexin 32 (Cx32), connexin 36 (Cx36), connexin 37 (Cx37), and connexin 43 (Cx43). Application of a battery of gap junction blockers from three different structural classes (carbenexolone, flufenamic acid, and long chain alcohols) substantially and consistently altered the locomotor-like activity in a dose-dependent manner. In contrast, these blockers did not significantly change the amplitude of the dorsal root reflex, indicating that gap junction blockers did not inhibit neuronal excitability nonselectively in the spinal cord. Taken together, these results suggest that gap junctions play a significant modulatory role in the spinal neural networks responsible for the generation of walking-like activity in the adult mudpuppy. PMID:27023006

  5. Methodological optimization of applying neuroactive agents for the study of locomotor-like activity in the mudpuppies (Necturus maculatus).

    PubMed

    Lavrov, Igor; Cheng, Jianguo

    2008-09-15

    We compared the effects of mode of delivery of neuroactive agents and the effects of dimethyl sulfoxide (DMSO), a vehicle for dissolving neuroactive agents, on locomotor-like activity in vitro. By superfusion, d-glutamate (0.3-0.9 mM) produced robust walking-like activity at superfusion rates 10-25 ml/min. In contrast, bolus application of the same or higher doses of glutamate (0.1-1.5 mM) failed to induce any rhythmic activity. Superfusion with AP-5, a NMDA receptor antagonist, produced dose-dependent inhibition of the ongoing walking-like activity induced by D-glutamate and completely blocked the activity at 20 microM. In contrast, bolus application of AP-5 did not block the walking-like activity at concentrations up to 120 microM. Similarly, superfusion of AP-5 inhibited the initiation of walking-like activity and completely blocked the initiation at 20 microM, while bolus application of AP-5 failed to do so at concentrations up to 120 microM. Superfusion of strychnine, a glycine receptor antagonist, blocked the walking-like activity at concentrations of 3-5 microM, while its bolus application altered NMDA-induced, but not glutamate-induced, walking-like activity to a synchronized pattern. DMSO significantly affected the walking-like activity in a dose-dependent manner at concentrations ranging 1-10% (v/v). These results demonstrate that the way by which the neuroactive agents are applied is a significant factor that determines the outcome of experiments on the neural control of locomotion. Also, the dose-dependent effects of DMSO on the activity of neural networks for locomotion should be taken into account in data interpretation. PMID:18692523

  6. Gap Junctions Contribute to the Regulation of Walking-Like Activity in the Adult Mudpuppy (Necturus Maculatus).

    PubMed

    Lavrov, Igor; Fox, Lyle; Shen, Jun; Han, Yingchun; Cheng, Jianguo

    2016-01-01

    Although gap junctions are widely expressed in the developing central nervous system, the role of electrical coupling of neurons and glial cells via gap junctions in the spinal cord in adults is largely unknown. We investigated whether gap junctions are expressed in the mature spinal cord of the mudpuppy and tested the effects of applying gap junction blocker on the walking-like activity induced by NMDA or glutamate in an in vitro mudpuppy preparation. We found that glial and neural cells in the mudpuppy spinal cord expressed different types of connexins that include connexin 32 (Cx32), connexin 36 (Cx36), connexin 37 (Cx37), and connexin 43 (Cx43). Application of a battery of gap junction blockers from three different structural classes (carbenexolone, flufenamic acid, and long chain alcohols) substantially and consistently altered the locomotor-like activity in a dose-dependent manner. In contrast, these blockers did not significantly change the amplitude of the dorsal root reflex, indicating that gap junction blockers did not inhibit neuronal excitability nonselectively in the spinal cord. Taken together, these results suggest that gap junctions play a significant modulatory role in the spinal neural networks responsible for the generation of walking-like activity in the adult mudpuppy. PMID:27023006

  7. Parambassis serrata, a new species of glassperch (Teleostei: Ambassidae) from the Kaladan drainage, India.

    PubMed

    Dishma, Mayanglambam; Vishwanath, Waikhom

    2015-01-01

    Parambassis serrata, a new species of glassperch from the Kolo River, Kaladan drainage, Mizoram, India is described. It is distinguished from its congeners by the combination of characters that includes: presence of a faint, vertically-elongated brown humeral blotch; posterior margin of most spines of first dorsal fin proximally blackish; 14-16 dorsal and anal-fin branched rays; a black longitudinal stripe on ventral surface of caudal peduncle; absence of predorsal scales; a serrated preopercular ridge; 51-56 scales in lateral series; and 11 pectoral-fin rays. PMID:26624693

  8. Length variation and sequence divergence in mitochondrial control region of Schizothoracine (Teleostei: Cyperinidae) species.

    PubMed

    Syed, Mudasir Ahmad; Bhat, Farooz Ahmad; Balkhi, Masood-Ul Hassan; Bhat, Bilal Ahmad

    2016-03-01

    Schizothoracine fish commonly called snow trouts inhibit the entire network of snow and spring fed cool waters of Kashmir, India. Over 10 species reported earlier, only five species have been found, these include Schizothorax niger, Schizothorax esocinus, Schizothorax plagiostomus, Schizothorax curvifrons and Schizothorax labiatus. The relationship between these species is contradicting. To understand the evolutionary relation of these species, we examined the sequence information of mitochondrial D-loop of 25 individuals representing five species. Sequence alignment showed D-loop region highly variable and length variation was observed in di-nucleotide (TA)n microsatellite between and within species. Interestingly, all these species have (TA)n microsatellite not associated with longer tandem repeats at the 3' end of the mitochondrial control region and do not show heteroplasmy. Our analysis also indicates the presence of four conserved sequence blocks (CSB), CSB-D, CSB-1, CSB-II and CSB-III, four (Termination Associated Sequence) TAS motifs and 15bp pyrimidine block within the mitochondrial control region, that are highly conserved within genus Schizothorax when compared with other species. The phylogenetic analysis carried by Maximum likelihood (ML), Neighbor Joining (NJ) and Bayesian inference (BI) generated almost identical results. The resultant BI tree showed a close genetic relationship of all the five species and supports two distinct grouping of S. esocinus species. Besides the species relation, the presence of length variation in tandem repeats is attributed to differences in predicting the stability of secondary structures. The role of CSBs and TASs, reported so far as main regulatory signals, would explain the conservation of these elements in evolution. PMID:25109626

  9. A new species of Barbatula from the Russian Altai (Teleostei: Nemacheilidae).

    PubMed

    Prokofiev, Artem M

    2015-01-01

    Barbatula restricta, new species, is described from the Saldan-Kol Lake in the upper Ob River drainage in the Altai Mountains. It is distinguished from all other species of Barbatula in Asia by its body depth increasing continuously between the nape and the dorsal-fin origin and a combination of characters: nares widely spaced, upper lip with a short medial incision, lower lip without lateral expansions, mental lobes of lower lip without conical protrusions, tips of paired fins formed by 1st and 2nd branched rays, 42-45 (mean 44) vertebrae, color pattern consisting of small irregular mottles without saddles on back. An overview of the status of all nominal Asiatic Barbatula species described is given. PMID:26701442

  10. 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.

  11. A new species of Saturnius Manter, 1969 (Digenea: Hemiuridae) from Mediterranean mullet (Teleostei: Mugilidae).

    PubMed

    Marzoug, Douniazed; Rima, Mohamed; Boutiba, Zitouni; Georgieva, Simona; Kostadinova, Aneta; Pérez-del-Olmo, Ana

    2014-02-01

    A new hemiurid digenean, Saturnius gibsoni n. sp., is described from the stomach lining of Mugil cephalus L. off Oran, Mediterranean coast of Algeria. Characteristic morphological features of the new species include small size of the body which is comprised of six pseudosegments, small ventral sucker, weakly developed mound-shaped flange at the level of the ventral sucker, and eggs being large in relation to the size of the body. Saturnius gibsoni n. sp. resembles S. minutus Blasco-Costa, Pankov, Gibson, Balbuena, Raga, Sarabeev & Kostadinova, 2006 and two unidentified Saturnius spp. in the small size of the body and most metrical features. However, in spite of the presence of five transverse septa resulting in six pseudosegments and the range overlap of some metrical features, the ventral sucker in S. minutus is much larger, the ventral sucker muscular flange is more prominent, the last pseudosegment is narrower in relation to body width and more rounded, and the eggs are smaller (mean 21 × 10 vs 25 × 12 μm). Furthermore, the partial sequences of the 28S rRNA gene region (domains D1-D3; 1,195 nt) obtained from two isolates of S. gibsoni n. sp. differed by 11 nt (0.9%) from that of S. minutus. Both unidentified forms of Saturnius are clearly distinguishable from S. gibsoni n. sp. by the presence of six stout, transverse muscular septa, forming seven pseudosegments (vs five septa forming six pseudosegments). Bayesian inference analysis of partial 28S rDNA sequences based on a total of 15 species from the families Hemiuridae and Lecithasteridae depicted the Bunocotylinae Dollfus, 1950 as a strongly supported basal clade, with Bunocotyle progenetica (Markowski, 1936) as the closest sister taxon to Saturnius spp. PMID:24474036

  12. Preliminary field study of hepatic porphyrin profiles of Astyanax fasciatus (Teleostei, Characiformes) to define anthropogenic pollution.

    PubMed

    Carrasco-Letelier, Leonidas; Eguren, Gabriela; de Mello, Franco Teixeira; Groves, Phillip A

    2006-03-01

    The implementation of eco-toxicological assessment in South America is presently limited due to significant scientific information gaps concerning native species and their potential use as biomarkers. Recently, a common southern hemisphere fish species, Astyanax fasciatus, has been pointed out as a potential bio-indicator to anthropogenic pollution. This is a small, abundant, Neotropical characid, which is widely distributed from Central America south, to the Rio de la Plata Basin of western Uruguay. Our study found a statistically significant increase of coproporphyrin, uroporphyrin and protoporphyrin concentrations in hepatic tissues of A. fasciatus collected from a stream segment with high anthropogenic disturbance (due mainly to agricultural derivatives and motor vehicle transportation activities). Although the area studied showed differences in up and downstream limno-chemical parameters, these differences were not related to the increase of hepatic porphyrin concentrations. Based on the results of our study, we conclude that A. fasciatus is a good bio-indicator of exposure to environmental contaminants, and we propose that this abundant fish species be considered as a sentinel organism for monitoring potential disturbances to freshwater ecosystems. PMID:16153685

  13. The complete mitochondrial genome of Schizopygopsis chengi baoxingensis (Teleostei, Cyprinidae, Schizopygopsis).

    PubMed

    Li, Hua; Huang, Yong; Li, Qiang; Chen, Yeyu; Liu, Ya; Liu, Guangxun

    2016-05-01

    Schizopygopsis chengi baoxingensis is endemic to the Baoxing River in China and may become an endangered species due to its very narrow habitat and the construction of hydropower dams. In this study, we successfully sequenced the first mitochondrial genome of S. c. baoxingensis. The mitogenome is 16,787 bp in length, containing 13 protein-coding genes, two rRNA genes, 22 tRNA genes and a control region (D-loop). The overall base composition of the H-strand is 28.5% A, 26.2% T, 18.4% C, and 26.9% G, with a slight AT bias of 54.7%. The sequenced mtDNA genome of S. c. baoxingensis is similar in gene arrangement to that of other cyprinidaes except for a 191 bp non-coding region found between tRNA(Thr) and tRNA(Pro). PMID:25391033

  14. 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. PMID:25698355

  15. The complete mitochondrial genome of Schizothorax chongi (Fang, 1936) (Teleostei, Cyprinidae, Schizothoracinae).

    PubMed

    Que, Yan-Fu; Xu, Dong-Mei; Li, Wei-Tao; Yang, Zhi; Tang, Hui-Yuan; Shao, Ke

    2016-03-01

    Schizothorax chongi is an endemic and important polyploidy fish in the upper stream of the Yangtze River. S. chongi represents a typical model species to study historical adaptation and evolution in the Tibetan Plateau. In this study, the complete mitochondrial DNA genome sequence of S. chongi was first determined by DNA sequencing based on the PCR fragments. The complete mitochondrial DNA (mtDNA) genome sequence of S. chongi is a circular molecule of 16,584?bp in length. It consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a control region (D-loop). The gene nucleotide composition of S. chongi is 29.6% A, 27.1% C, 17.9% G, and 25.4% T, with a high AT content (55.0%). The results could provide useful data for further studies on phylogenetics, conservation genetics and rational resource management for S. chongi. PMID:24865916

  16. New insights into karyotypic relationships among populations of Astyanax bockmanni (Teleostei, Characiformes) of different watersheds.

    PubMed

    Daniel, Sandro Natal; Penitente, Manolo; Hashimoto, Diogo Teruo; de Andrade Silva, Duílio Mazzoni Zerbinato; Foresti, Fausto; Porto-Foresti, Fábio

    2015-04-01

    The fish constitute about 50% of all vertebrates, including a wide morphological and biological diversity, where the genus Astyanax is the most common and diverse, as described in virtually all freshwater environments. By occupying a basal position in the phylogeny of vertebrates, fish are an extremely favorable group for cytogenetic and evolutionary studies. The karyotype found in genus Astyanax diversity may involve a number of polymorphisms, which may be related to ploidy and karyotypic macrostructure, presence of B chromosomes, heterochromatin polymorphisms, and location of ribosomal genes. Nevertheless, the relationship between populations of this species is still poorly studied. Thus, the present work aimed to investigate karyotype variation, chromosomal relationships, and the behavior of 5S and 18S ribosomal genes in six populations of Astyanax bockmanni. The results confirmed the diploid number of 50 chromosomes in all the populations sampled, with the occurrence of one supernumerary chromosome in just one of them. In addition, all populations showed divergent patterns of constitutive heterochromatin and repetitive nucleolar sites. The fluorescence in situ hybridization (FISH) technique using 5S and 18S rDNA probes revealed distinct patterns of distribution for these conserved genes, while 5S rDNA genes were found located in two chromosome pairs, the 18S genes showed multiple marks dispersed in the genome characterizing an inter and intraindividual polymorphic behavior, as previously reported to occur with the utilization of the Ag-NOR technique. Thus, besides minor modifications observed in chromosome morphology, the populations of A. bockmanni analyzed revealed a preserved macrostructural feature, especially concerning to the diploid number; on the other hand, differences in microstructural characteristics indicated by the nucleolus organizer region (NOR) location, constitutive heterochromatin patterns, and distribution of ribosomal genes along the genome were clearly evident in the populations from different river basins, even located at short distances. PMID:25714526

  17. 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. PMID:25549800

  18. Historical biogeography and speciation in the reef fish genus Haemulon (Teleostei: Haemulidae).

    PubMed

    Rocha, Luiz A; Lindeman, Kenyon C; Rocha, Claudia R; Lessios, H A

    2008-09-01

    The high biodiversity of tropical marine hotspots has long intrigued evolutionary biologists and biogeographers. The genus Haemulon (grunts) is one of the most important (numerically, ecologically, and economically) reef fish groups in the New World and an excellent candidate to test hypotheses of speciation and diversity generation in the Greater Caribbean, the richest Atlantic biodiversity hotspot, as well as the eastern Pacific. To elucidate the phylogenetic relationships among the species of Haemulon, we obtained a combined total of 2639 base pairs from two mitochondrial genes (cytochrome b and cytochrome oxidase I), and two nuclear genes (TMO-4C4 and RAG2) from all nominal species. Parsimony, Maximum likelihood, and Bayesian analyses resulted in a well-resolved phylogeny with almost identical topologies. Previous phylogenetic hypotheses based on adult morphology, such as the close relationship among H. aurolineatum, H. boschmae, and H. striatum were not supported, whereas others using developmental characters, such as the relationship between H. plumieri and H. sciurus, were confirmed. Our data also indicate that the populations of the nominal H. steindachneri from the two sides of the Isthmus of Panama are genetically divergent at the species level in each ocean, and that the boga, Inermia vittata (family Inermiidae), belongs in the genus Haemulon. This evidence implies that there are 21 valid species of Haemulon, two more than previously recognized. The Amazon barrier and the Isthmus of Panama seem to have played roles in allopatric speciation of Haemulon. However, the majority of sister species pairs have completely overlapping distributions, indicating that vicariance is not the only process driving speciation in this genus. We conclude that both vicariance between biogeographic provinces, and ecological mechanisms of speciation within provinces contribute to species richness in the genus Haemulon. PMID:18599320

  19. 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

  20. First record of the Atlantic bumper Chloroscombrus chrysurus (Teleostei: Carangidae) in the Mediterranean Sea.

    PubMed

    Peña Rivas, L; Azzurro, E; Lloris, D

    2013-03-01

    In December 1997, one specimen of the Atlantic bumper, Chloroscombrus chrysurus was recorded for the first time in the Mediterranean Sea, off Almuñécar (Granada, Spain: 36° 43' 26″ N; 3° 41' 39″ W). This species probably entered the Mediterranean Sea via the Strait of Gibraltar. PMID:23464561

  1. Stages in the early and larval development of the African catfish Clarias gariepinus (Teleostei, Clariidae).

    PubMed

    Olaniyi, Wasiu Adekunle; Omitogun, Ofelia Galman

    2014-08-01

    The African catfish Clarias gariepinus Burchell 1822 is a favourite aquaculture fish in many parts of Africa and Asia because of its hardiness and fast growth rate. In this study, early, post-embryonic and larval developmental stages of C. gariepinus were examined chronologically and described. Photomicrographs of unfertilized matured oocytes from 0 min of fertilization through all cell stages to alevin, to complete yolk absorption, to free swimming larval stages are shown and documented live from lateral and top views, with the aid of a light microscope. Extruded oocytes had a mean diameter of 1 ± 0.1 mm, and possessed a thin perivitelline membrane whose space was filled with a protoplasmic layer. Heartbeat was in the range of 115-160/min prior to hatching. Hatchability rate was 85% and hatching occurred at 17 h at a controlled temperature of 28.5 ± 0.5°C, while ontogeny of the eyes and other organs were discernible. At day 4, larvae mean length was 9.3 ± 0.5 mm, exogenous feeding had commenced fully and melanophores spread cephalocaudally but were concentrated significantly on the head parts. This paper, for the first time, presents the significant chronological developmental stages of C. gariepinus embryology that will have significant implications for genetic manipulation and catfish seed production for aquaculture. PMID:23534899

  2. Spawning migrations of the endemic Labeobarbus (Cyprinidae, Teleostei) species of Lake Tana, Ethiopia: status and threats.

    PubMed

    Anteneh, W; Getahun, A; Dejen, E; Sibbing, F A; Nagelkerke, L A J; De Graaf, M; Wudneh, T; Vijverberg, J; Palstra, A P

    2012-07-01

    The reproductive biology of the only known intact species flock of large cyprinids, the 16 Labeobarbus species of Lake Tana (Ethiopia), has been extensively studied for the past two decades. Seven species of Labeobarbus are known to migrate >50 km upstream into tributary rivers for spawning during the rainy season (July to October), whereas eight other species are absent from these rivers and probably developed a new strategy of lacustrine spawning (macro-spatial segregation). One species (L. intermedius) probably spawns in the lake as well as in the rivers. Between the early 1990s and 2000s, the riverine spawners showed a decline of 75% in both biomass and number in both fishery independent surveys and in commercial catches. Reproductive migration makes fishes vulnerable to fisheries and other threats like habitat modifications. Lacustrine spawners are probably more resilient as they are not known to form spawning aggregations that can easily be exploited by fishermen. In addition, upstream rivers and catchments around Lake Tana are highly degraded by erosion and recently subjected to intensive habitat modification for irrigation and hydroelectric power generation. This article reviews results of field studies on the Labeobarbus spawning migration from Lake Tana to spawning rivers, giving emphasis on segregation and homing. It also summarizes existing and emerging threats which form potential causes for the decline of the migratory Labeobarbus species. Knowledge gaps on the reproductive biology are identified for further investigation. PMID:22803734

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

    PubMed

    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. Phylogeny of moray eels (Anguilliformes: Muraenidae), with a revised classification of true eels (Teleostei: Elopomorpha: Anguilliformes).

    PubMed

    Tang, Kevin L; Fielitz, Christopher

    2013-02-01

    The family Muraenidae is one of the largest and most recognizable eel groups. Moray eels are key components of marine ecosystems but their relationships remain poorly understood. The phylogenetic relationships of the morays are examined herein using mitochondrial 12S and 16S sequence data, totaling 1673 bp for 139 taxa. The results of our analyses found support for a monophyletic family Muraenidae that is part of a monophyletic suborder Muraenoidei, which is revised to include the anguilliform families Heterenchelyidae and Myrocongridae, and to exclude the family Chlopsidae. The muraenids form two monophyletic subfamilies, Muraeninae and Uropterygiinae. Of the genera that had multiple species included for analysis, only the type genus of the family, Muraena, is found to be monophyletic. In the subfamily Uropterygiinae, Uropterygius is not recovered as a monophyletic genus. In the subfamily Muraeninae, the species-rich piscivorous genera, Enchelycore and Gymnothorax, and the durophagous genus, Echidna, are demonstrably not monophyletic. The monotypic Gymnomuraena is the sister group to all other muraenine species. The relationships within Muraenidae require much additional study and its genera remain in urgent need of revision. The order Anguilliformes is revised herein to include four suborders: Anguilloidei, Congroidei, Muraenoidei, and Synaphobranchoidei. All four families of the order Saccopharyngiformes are nested within Anguilliformes, recovered as part of a clade that includes Anguillidae; the saccopharyngiform families are referred to the suborder Anguilloidei sensu novum. PMID:22967094

  5. Complete mitochondrial genome of the natural pentaploid loach, Misgurnus anguillicaudatus (Teleostei: Cypriniformes: Cobitididae).

    PubMed

    Zeng, Yu; Chen, Yong-bo; Pan, Bao-zhu; Zhang, Da-wen

    2016-01-01

    The complete mitochondrial genome of the natural pentaploid loach Misgurnus anguillicaudatus is a circular molecule of 16,643 bp in size, containing 13 protein-coding genes, 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes, and two main noncoding regions (the control region and the origin of the light strand replication). Most of the genes are encoded on the heavy strand, except for ND6 and eight tRNAs. The control region is 918 bp in length and located between the tRNA(Pro) and tRNA(Phe) genes, some typical conserved elements (TAS, CSB1-3 and CSB D-F) were found in this region. All these features reflect a typical vertebrate mitochondrial gene arrangement of the pentaploid M. anguillicaudatus. PMID:25162828

  6. The complete mitochondrial genome of Hoeven's mullet-goby Hemigobius hoevenii (Bleeker) (Teleostei, Gobiidae).

    PubMed

    Huang, Shih-Pin; Shen, Chia-Ning; Chen, I-Shiung

    2016-01-01

    In this study, the complete mitochondrial genome of Hoeven's mullet-goby Hemigobius hoevenii (Bleeker, 1851) collected from Malay Peninsula has been amplified and sequenced. The complete mitochondrial genome is 16,469 base pairs (bp) in total length, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 2 rRNAs, 22 tRNAs, 1 control region (CR) and 1 light-strand replication origin (OL). The overall base composition of H. hoevenii is 27.1% for A, 26.6% for T, 29.0% for C, 17.3% for G, with higher AT content 53.7%. This study will contribute for understanding the phylogenetic approach of Hemigobius species as well as the related genera of gobiid fishes. PMID:24779596

  7. The complete mitochondrial genome of the Abe's mangrove goby Mugilogobius abei (Teleostei, Gobiidae).

    PubMed

    Huang, Shih-Pin; Shen, Chia-Ning; Chen, I-Shiung

    2015-02-01

    In this study, the complete mitochondrial genome of the Abe's mangrove goby Mugilogobius abei has been amplified. Mugilogobius abei is widely contributed species in Northeast to East Asia. The complete mitogenome is 16,483 base pairs (bp) in total length, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 2 rRNAs, 22 tRNAs, and 1 control region (CR). The overall base composition of M. abei is 27.7% for A, 27.0% for T, 28.6% for C, 16.7% for G, with higher AT content of 54.7%. This study will contribute for understanding the phylogenetic approach in genus Mugilogobius and related gobiid genera. PMID:23901918

  8. The complete mitochondrial genome of the Java fat-nose goby Pseudogobius javanicus (Teleostei, Gobiidae).

    PubMed

    Huang, Shih-Pin; Shen, Chia-Ning; Chen, I-Shiung

    2015-02-01

    In this study, the complete mitochondrial genome of the fat-nose goby Pseudogobius javanicus has been amplified. P. javanicus is widely contributed species in Southeast to East Asia. The complete mitochondrial genome is 16,493 base pairs (bp) in total length, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 2 rRNAs, 22 tRNAs, 1 control region (CR) and 1 light-strand replication origin (OL). The overall base composition of P. javanicus is 27.1% for A, 27.3% for T, 28.6% for C, 17.0% for G, with higher AT content of 54.4%. This study will contribute for understanding the phylogenetic approach in genus Pseudogobius. PMID:23901921

  9. Prey selection of the shallow water fish Pomatoschistus minutus (Gobiidae, Teleostei) in the SW Baltic

    NASA Astrophysics Data System (ADS)

    Zander, C. Dieter

    1990-06-01

    The aim of this investigation is to demonstrate the reasons of an opportunist feeder to select some components of the available food supply and to avoid others. Object of this test is the eurytopic and euryhaline sand goby, Pomatoschistus minutus (Pallas), from the Luebeck Bight. It inhabits both sand habitats as well as bottoms mixed with pebbles or continuous hard substrates. Therefore, it is often in close contact with Mytilus-belts which present a very rich food supply of small crustaceans. The selectivity behaviour of sand gobies from a sand/clay ecotone was compared with that of populations from a stony pier and a sand bottom during the reproduction period. Regarding the numbers of prey organisms, crustaceans of the periphyton were generally preferred at the pier but avoided in the ecotone. The same is valid for prey organisms of the psammal which were preferred by gobies of the sand bottom but mostly avoided by populations of mixed bottoms. Analyses of size selections revealed that the preferred gammarids or Jaera isopods were between 2 and 5 mm length. A balanced relation of goby biomass and utilizable food supply (predatory impact index) seems to effect positive selectivity of gammarids in the Mytilus-belts or of harpacticoids in the sand bottom.

  10. Eviota santanai, a new Dwarfgoby from Timor-Leste (Teleostei: Gobiidae).

    PubMed

    Greenfield, David W; Erdmann, Mark V

    2013-01-01

    Eviota santanai is described based on four specimens from Timor-Leste, taken in 5-8 m depth. In general coloration pattern, the species is most similar to E. latifasciata, but differs in the cephalic sensory-pore system pattern, the absence of an occipital spot, and live color including pinkish-mauve bars. Eviota santanai has a dorsal/anal fin-ray formula of 8/8, 5th pelvic-fin ray absent, some lower pectoral-fin rays branched, and IT and PITO pores absent. PMID:25113009

  11. Descriptions of three new species of Glossogobius (Teleostei: Gobiidae) from New Guinea.

    PubMed

    Hoese, Douglass F; Allen, Gerald R

    2015-01-01

    Three new species of Glossogobius are described from New Guinea. Glossogobius multipapillus, n. sp. from northeastern New Guinea has a lobed mental fraenum and a distinctive papilla pattern unlike any other species in the genus. Glossogobius sentaniensis, n. sp. is described from Lake Sentani. The species is similar to Glossogobius aureus and G. koragensis differing in head pores and large dark spots on the body. Glossogobius macrocephalus n. sp. from Lake Tebera and surrounding rivers has a lobed mental fraenum and differs from other species in the Glossogobius celebius group in the combination of having a large head, head pore, fin-ray and predorsal scale counts. PMID:26250181

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

    PubMed

    Van Tassell, James L; Kramer, Annemarie

    2014-01-01

    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.  PMID:24870184

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

    PubMed

    Greenfield, David W; Tornabene, Luke

    2014-01-01

    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. PMID:24870157

  14. The complete mitogenome of the Murray Cod, Maccullochella peelii (Mitchell, 1838) (Teleostei: Percichthyidae).

    PubMed

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

    2016-01-01

    The complete mitochondrial genome of the iconic Australian freshwater fish, the Murray Cod, Maccullochella peelii, was recovered from partial genome sequencing data using the HiSeq platform (Illumina, San Diego, CA). The mitogenome consists of 16,442 bp (58% A + T content) containing 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs, and a 768 bp non-coding AT-rich region. This is the first mitogenome sequence for the genus Maccullochella, and the fourth for the family Percichthyidae. PMID:24779601

  15. 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. PMID:24638897

  16. 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. J. Morphol. 277:65-85, 2016. © 2015 Wiley Periodicals, Inc. PMID:26395188

  17. Extensive spreading of interstitial telomeric sites on the chromosomes of Characidium (Teleostei, Characiformes).

    PubMed

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

    2015-06-01

    Characidium comprises several species of small freshwater fish that display conserved diploid chromosome numbers and karyotypic formulae. In this study, a comparative cytogenetic analysis using telomeric DNA probes was carried out in nine species of Characidium; a molecular phylogenetic analysis with mitochondrial DNA was also performed in order to investigate the direction of the evolutionary chromosome changes observed here. Our results showed the existence of species with several and variable interstitial telomeric sites (ITSs), with other species showing only terminal signals in their chromosomes. Molecular phylogenetic data suggested that these ITSs emerged once in the evolutionary history of Characidium and were later differentially spread in distinct species/populations of this clade. Additionally, the origin of an exclusive acrocentric pair found in C. pterostictum, C. serrano and C. timbuiense was also investigated, revealing that this pair possibly had a common origin to these species. These results evidence the occurrence of intense and continuous genomic changes among species of Characidium. PMID:25547849

  18. 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. PMID:26721557

  19. Taxonomic revision and molecular phylogeny of Gymnocorymbus Eigenmann, 1908 (Teleostei, Characiformes, Characidae).

    PubMed

    Benine, Ricardo C; Melo, Bruno F; Castro, Ricardo M C; Oliveira, Claudio

    2015-01-01

    Characidae, one of the most diverse families of Characiformes and one of the largest clades of fishes in the world, has a complex taxonomic background, with one issue being the placement of various genera, including Gymnocorymbus. Herein, we generate the first molecular phylogeny for the genus using three nuclear and two mitochondrial loci and review the systematics of Gymnocorymbus. This genus includes the black tetra, a well-known and popular species among aquarists. Molecular phylogeny strongly supports the monophyly of Gymnocorymbus, with this hypothesis corroborated by the presence of three morphological synapomorphies. Of the six previously known nominal species of Gymnocorymbus, three are considered valid herein: Gymnocorymbus bondi from the Río Orinoco basin, Gymnocorymbus ternetzi from the Rio Paraguay basin, and Gymnocorymbus thayeri from the Corantijn and Amazon basin and rivers of northeastern Brazil. A fourth species, Gymnocorymbus flaviolimai sp. n., is described from the Rio Madeira, Amazon basin. Lectotypes are designated for G. ternetzi and G. thayeri. Our results support previous hypotheses of the alignment of Gymnocorymbus close to the subfamily Stethaprioninae and also support the sister relationship between G. ternetzi and G. thayeri, and of that clade as sister to G. bondi. PMID:26248902

  20. 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. PMID:26541240

  1. 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

    2015-01-01

    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. PMID:26250251

  2. Microsatellite Development for an Endangered Bream Megalobrama pellegrini (Teleostei, Cyprinidae) Using 454 Sequencing

    PubMed Central

    Wang, Jinjin; Yu, Xiaomu; Zhao, Kai; Zhang, Yaoguang; Tong, Jingou; Peng, Zuogang

    2012-01-01

    Megalobrama pellegrini is an endemic fish species found in the upper Yangtze River basin in China. This species has become endangered due to the construction of the Three Gorges Dam and overfishing. However, the available genetic data for this species is limited. Here, we developed 26 polymorphic microsatellite markers from the M. pellegrini genome using next-generation sequencing techniques. A total of 257,497 raw reads were obtained from a quarter-plate run on 454 GS-FLX titanium platforms and 49,811 unique sequences were generated with an average length of 404 bp; 24,522 (49.2%) sequences contained microsatellite repeats. Of the 53 loci screened, 33 were amplified successfully and 26 were polymorphic. The genetic diversity in M. pellegrini was moderate, with an average of 3.08 alleles per locus, and the mean observed and expected heterozygosity were 0.47 and 0.51, respectively. In addition, we tested cross-species amplification for all 33 loci in four additional breams: M. amblycephala, M. skolkovii, M. terminalis, and Sinibrama wui. The cross-species amplification showed a significant high level of transferability (79%–97%), which might be due to their dramatically close genetic relationships. The polymorphic microsatellites developed in the current study will not only contribute to further conservation genetic studies and parentage analyses of this endangered species, but also facilitate future work on the other closely related species. PMID:22489139

  3. 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. PMID:26114323

  4. 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.

  5. Chromosomal location of retrotransposable REX 1 in the genomes in five Prochilodus (Teleostei: Characiformes.

    PubMed

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

    2013-07-01

    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

  6. 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

  7. 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

  8. Genetic and biogeographical relationships among species of Astyanax (Teleostei, Characidae) in Brazilian river basins.

    PubMed

    Mello, R; Maniglia, T C; Prioli, S M A P; Prioli, A J

    2015-01-01

    The genetic relationships among 17 species of Astyanax from the Iguaçu River and adjacent river basins in Brazil were examined using nucleotide sequences of the mitochondrial cytochrome b gene (cytb). Congruent trees were constructed using neighbor-joining, maximum-likelihood, and Bayesian methods. The resulting clades suggest that at least three major groups share similar origins with the endemic species of the Iguaçu River. The results indicate that Astyanax is polyphyletic in this location, which suggests that Astyanax did not diversify from a single ancestral group that was isolated when the Iguaçu River basin formed. Astyanax bifasciatus shares an origin with some species of the altiparanae-bimaculatus complex, while A. minor originated from the same group as A. aff. paranae, A. fasciatus, and A. bockmanni. The third group includes A. dissimilis, Astyanax sp F, and A. serratus that are endemic species to the Iguaçu River basin. Geological and hydrological events that influenced the biogeographical patterns of these species are discussed. PMID:26634501

  9. 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. PMID:26753081

  10. 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

  11. Comparative analysis of sex chromosomes in Leporinus species (Teleostei, Characiformes) using chromosome painting

    PubMed Central

    2013-01-01

    Background The Leporinus genus, belonging to the Anostomidae family, is an interesting model for studies of sex chromosome evolution in fish, particularly because of the presence of heteromorphic sex chromosomes only in some species of the genus. In this study we used W chromosome-derived probes in a series of cross species chromosome painting experiments to try to understand events of sex chromosome evolution in this family. Results W chromosome painting probes from Leporinus elongatus, L. macrocephalus and L. obtusidens were hybridized to each others chromosomes. The results showed signals along their W chromosomes and the use of L. elongatus W probe against L. macrocephalus and L. obtusidens also showed signals over the Z chromosome. No signals were observed when the later aforementioned probe was used in hybridization procedures against other four Anostomidae species without sex chromosomes. Conclusions Our results demonstrate a common origin of sex chromosomes in L. elongatus, L. macrocephalus and L. obtusidens but suggest that the L. elongatus chromosome system is at a different evolutionary stage. The absence of signals in the species without differentiated sex chromosomes does not exclude the possibility of cryptic sex chromosomes, but they must contain other Leporinus W sequences than those described here. PMID:23822802

  12. Complete mitogenomes of Woodhead's angelfish (Centropyge woodheadi) and Herald's angelfish (Centropyge heraldi) (Teleostei: Pomacanthidae).

    PubMed

    Shen, Kang-Ning; Chang, Chih-Wei; Chan, Yen-Fan; Lin, Zi-Han; Tsai, Shiou-Yi; Chen, Ching-Hung; Hsiao, Chung-Der

    2016-09-01

    In this study, we used the next-generation sequencing method to deduce two complete mitogenomes of Woodhead's angelfish (Centropyge woodheadi) and Herald's angelfish (Centropyge heraldi) for the first time. The assembled mitogenome, consisting of 16 863 and 16 836 bp, shows 95.3% identity to each other. Both mitogenome follow a typical vertebrate arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes and a non-coding control region of D-loop. D-loop contains 1158 bp in C. woodheadi and 1129 bp in C. heraldi and locates between tRNA-Pro and tRNA-Phe. The overall GC content is 47.9% for C. woodheadi and 47.5% for C. heraldi. The complete mitogenomes of C. woodheadi and C. heraldi provide an essential and important DNA molecular data for phylogenetic and evolutionary analysis for marine angelfish. PMID:26328622

  13. Complete mitogenomes of Cocos lemonpeel angelfish (Centropyge flavissima) and Eibl's angelfish (Centropyge eibli) (Teleostei: Pomacanthidae).

    PubMed

    Shen, Kang-Ning; Chang, Chih-Wei; Lin, Zi-Han; Chan, Yen-Fan; Tsai, Shiou-Yi; Chen, Ching-Hung; Hsiao, Chung-Der

    2016-09-01

    In this study, we used the next-generation sequencing method to deduce two complete mitogenomes of Cocos lemonpeel angelfish (Centropyge flavissima) and Eibl's angelfish (Centropyge eibli) for the first time. The assembled mitogenome, consisting of 17 010 bp and 17 101 bp, showing 98.3% identity each other. Both mitogenomes follow the typical vertebrate arrangement, including 13 protein coding genes, 22 transfer RNAs, two ribosomal RNA genes, and a non-coding control region of D-loop. D-loop contains 1302 bp in C. flavissima and 1392 bp in C. eibli and locates between tRNA-Pro and tRNA-Phe. The overall GC content is 45.2% for C. flavissima and 44.9% for C. eibli. Complete mitogenomes of C. flavissima and C. eibli provide essential and important DNA molecular data for phylogenetic and evolutionary analysis for marine angelfishes. PMID:26330270

  14. 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

  15. 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. PMID:24832903

  16. Microsatellite development for an endangered bream Megalobrama pellegrini (Teleostei, Cyprinidae) using 454 sequencing.

    PubMed

    Wang, Jinjin; Yu, Xiaomu; Zhao, Kai; Zhang, Yaoguang; Tong, Jingou; Peng, Zuogang

    2012-01-01

    Megalobrama pellegrini is an endemic fish species found in the upper Yangtze River basin in China. This species has become endangered due to the construction of the Three Gorges Dam and overfishing. However, the available genetic data for this species is limited. Here, we developed 26 polymorphic microsatellite markers from the M. pellegrini genome using next-generation sequencing techniques. A total of 257,497 raw reads were obtained from a quarter-plate run on 454 GS-FLX titanium platforms and 49,811 unique sequences were generated with an average length of 404 bp; 24,522 (49.2%) sequences contained microsatellite repeats. Of the 53 loci screened, 33 were amplified successfully and 26 were polymorphic. The genetic diversity in M. pellegrini was moderate, with an average of 3.08 alleles per locus, and the mean observed and expected heterozygosity were 0.47 and 0.51, respectively. In addition, we tested cross-species amplification for all 33 loci in four additional breams: M. amblycephala, M. skolkovii, M. terminalis, and Sinibrama wui. The cross-species amplification showed a significant high level of transferability (79%-97%), which might be due to their dramatically close genetic relationships. The polymorphic microsatellites developed in the current study will not only contribute to further conservation genetic studies and parentage analyses of this endangered species, but also facilitate future work on the other closely related species. PMID:22489139

  17. Mitochondrial genome of the flat-lip gudgeon, Platysmacheilus exiguus (Teleostei, Cypriniformes).

    PubMed

    Xu, Hao; Xue, Yang; Ye, Qin; Luo, Xi; L, Hong-Jian; Chen, Da-Qing; Li, Yun

    2016-01-01

    The complete mitogenome of an endemic fish in China flat-lip gudgeon, Platysmacheilus exiguous, was determined using the polymerase chain reaction and directly sequenced with the primer walking method. The whole mitogenome was 16,604?bp in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and 1 control region. It had the typical circular molecule structure of vertebrate's mitogenome. The whole base composition was estimated to be 30.77%A, 26.06%T, 26.64%C and 16.53%G with AT bias of 56.83%. The complete mitogenome of P. exiguus provides the fundamental data for conservation genetics study on this species. PMID:24450708

  18. Description of a new species of Hemigrammocapoeta (Teleostei: Cyprinidae) from Lake I??kl?, Turkey.

    PubMed

    Kk, Fahrettin; Bayelebi, Esra; Gl, Salim Serkan; Glle, Iskender

    2015-01-01

    Hemigrammocapoeta menderesensis is distinguished from all other species of Hemigrammocapoeta in Anatolia by the following combination of characters (none unique to the species): lateral line incomplete; 6-17 perforated scales and 36-41 +1-2 scales in lateral series; 7-8 scale rows between lateral line and dorsal-fin origin, 3-4 scale rows between lateral series and anal-fin origin; dorsal fin commonly with 7 branched rays; anal fin with 5 branched rays; 15-17 gill rakers on the first brachial arch; pharyngeal teeth 2.4.5-5.3.3; mouth small, subterminal, horseshoe shaped and without barbel; lips developed and somewhat fleshy; upper lip not covering nostril gape; lower lip with two lateral lobes and median pad; lateral lobes smaller and shorter than half width of median pad; numerous papillae on lower and upper lips. PMID:26701435

  19. Electric signals in the social behavior of sympatric elephantfish (Mormyridae, Teleostei) from the upper Zambezi River.

    PubMed

    Scheffel, A; Kramer, B

    2000-03-01

    Electrocommunication in mormyrid fish from African freshwaters is a challenging research field in neuroethology (Turner et al. 1999). However, virtually nothing is known about electrocommunication within natural mormyrid populations involving sympatric, syntopic species. Here we report on the nocturnal activities and electrocommunication among three syntopic species in a spacious laboratory setting resembling the natural one. Petrocephalus catostoma, Cyphomyrus discorhynchus, and Hippopotamyrus sp. nov. differ characteristically in their behavior, such as in territorial defense, schooling, and joining members of other species during foraging. Comparing social encounters within and between species, the first evidence for interspecific electrocommunication among syntopic species was found. PMID:10798201

  20. 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

  1. The gulf surgeon, Acanthurus randalli, a junior synonym of the ocean surgeon, Acanthurus bahianus (teleostei: Acanthuridae)

    USGS Publications Warehouse

    Smith-Vaniz, W.F.; Jelks, H.L.; Randall, J.E.

    2003-01-01

    We compared 62 specimens, 48-126.5 mm standard length, of Acanthurus bahianus from the northeastern Gulf of Mexico with 95 specimens from other localities to determine if the distinguishing characters in the original description of the Gulf of Mexico endemic surgeonfish Acanthurus randalli were valid. No color pattern or meristic differences were found, and the only measurement that allowed distinction (91% percent concordance) was the shallower caudal concavity of northeastern Gulf of Mexico specimens. Acanthurus chirurgus from the northeastern Gulf of Mexico also have shallower caudal concavities (93.7% percent concordance) than do conspecifics from other areas, suggesting that this trend may be correlated with some unknown environmental influence. Considering the extended planktonic larval dispersal capabilities of Atlantic surgeonfishes, and that the single divergent morphological character state is also exhibited in a sympatric northeastern Gulf of Mexico population of A. chirurgus, recognition of A. randalli is untenable, and the name is considered a junior synonym of A. bahianus. An identification key to western Atlantic species of Acanthurus that incorporates the results of this study is given.

  2. 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

  3. Mitochondrial DNA variability to explore the relationship complexity of Schizothoracine (Teleostei: Cyprinidae).

    PubMed

    Ahmad, Syed Mudasir; Bhat, Farooz Ahmad; Balkhi, Masood-Ul Hassan; Bhat, Bilal Ahmad

    2014-12-01

    Despite numerous studies on the taxonomy of a highly complex group of schizothoracine (snow trouts), with over five recognized species from Kashmir, India (Schizothorax niger, Schizothorax esocinus, Schizothorax plagiostomus, Schizothorax curvifrons and Schizothorax labiatus) based on traditional morphological data, the relationships between these species is poorly understood and the taxonomic validity is still under debate. To resolve the evolutionary relationships among these species, we sequenced mitochondrial fragments, including 16Sr RNA, Cytb and the D-loop. Separate analyses of 16S and Cytb showed intermixing of the species and 16S was found more conserved than Cytb. The D-loop was found highly variable and showed length variation between and within species. Length variation was observed in di-nucleotide (TA)n microsatellite repeats with a variable number of repeat units (n = 7-14) that did not show heteroplasmy. Central conserved sequence blocks (CSBs) in D-loop sequences were found comparable to other vertebrate species. All phylogenetic reconstructions recovered the focal taxa as a monophyletic clade within the schizothoracines. Analyses with combined mitochondrial data sets showed close genetic relationships of all the five species. In addition to a close relationship between S. niger and S. curvifrons, two distinct groupings of S. ecoscinus and S. plagiostomus were supported by all the analyses. This study gives an insight into molecular phylogeny of the species and improves our understanding of historical and taxonomic relationships derived from morphological and ecological studies. PMID:25366848

  4. 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. PMID:27074006

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

    PubMed

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

    2014-01-01

    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. PMID:24869808

  6. 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

  7. Diet of Lipophrys pholis (L.) (Teleostei, Blenniidae) in Cantabrian coastal waters (Spain)

    NASA Astrophysics Data System (ADS)

    Mazé, Raquel A.; Domínguez, Josefa; Pérez-Cardenal, David

    1999-07-01

    Between February and December 1988, a total of 261 specimens of Lipophrys pholis were caught in eleven intertidal pools on the western coast of Asturias. This blenniid species mainly feeds on different groups of invertebrates, although algal remains also appear. Mollusca is the most highly represented taxon with the largest number of prey being Gastropoda, followed by Bivalvia and, to a lesser degree, Polyplacophora. Crustacea is well represented by Cirripedia. Isopoda also stands out and Amphipoda, Tanaidacea and Decapoda appear sporadically. Temporal diet analysis throughout the year shows no great differences. Likewise, a great similarity was observed among the feeding of L. pholis specimens collected in pools at a different tidal level, of variable size and with different algal cover. Changes in diet are appreciable as size increases, especially from a length of 6 cm on.

  8. Description of two new species of Laubuka (Teleostei: Cyprinidae) from River Cauvery, southern Iandia.

    PubMed

    Knight, J D Marcus

    2015-01-01

    Fishes currently identified as Laubuka laubuca from the Cauvery River and its tributaries in the Western Ghats of India are shown to represent two different species: Laubuka trevori, sp. nov., and L. latens, sp. nov., distinguished from all species of Chela and Laubuka by possessing 7½ branched dorsal-fin rays; 14 precaudal vertebrae; 17-18 predorsal scales; 5 branched pelvic-fin rays and 5+4+2 teeth on the fifth ceratobranchial. Laubuka trevori is further distinguished from its congeners by possessing 14½-15½ branched anal-fin rays; ½6/1/1½ scales in transverse line on body; a short pelvic fin (10.1-16.3% SL) and two longitudinal stripes: a golden and a bluish-green stripe on the body, running from behind the opercle to the base of the caudal fin, the latter broken and less distinct in the anterior half of the body. Laubuka latens is further distinguished by its long pelvic fin (23.2-26.9% SL) and the absence of any markings on the side of the body other than a humeral spot and a caudal-peduncle spot. PMID:26623743

  9. 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. PMID:25970628

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

    PubMed

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

    2015-01-01

    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: Cetopsorhamdiaiheringi (Schubart & Gomes, 1959), 2n = 58, comprising 28 metacentric (m) + 26 submetacentric (sm) + 4 subtelomeric (st) chromosomes; Pimelodellavittata (Lütken, 1874), 2n = 46, comprising 16m + 22sm + 8st; Rhamdiapropequelen (Quoy & Gaimard, 1824), 2n = 58 comprising 26m + 16sm + 14st + 2 acrocentric; and Rhamdiopsispropemicrocephala (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, Cetopsorhamdiaiheringi and Rhamdiapropequelen, 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

  11. Kudoa inornata sp. n. (Myxosporea: Multivalvulida) from the skeletal muscles of Cynoscion nebulosus (Teleostei: Sciaenidae).

    PubMed

    Dyková, Iva; de Buron, Isaure; Fiala, Ivan; Roumillat, William A

    2009-06-01

    A new myxosporean species, Kudoa inornata sp. n. (Myxosporea: Multivalvulida), is described from skeletal muscles of the spotted seatrout Cynoscion nebulosus (Cuvier), collected in estuarine waters along the coast of South Carolina, USA. Light microscopic and ultrastructural characters rank this species to the group of Kudoa species with simple-shaped spores. The uniqueness of the SSU and LSU rDNA sequences justifies its status of a new species with sister relationship to Kudoa paniformis. The 100% prevalence in seatrout from four out of five localities sampled and pathogenicity of K. inornata recognized in this study should motivate further screening for infections in its host, which is considered a commercially important game fish with a wide distribution in the Western North Atlantic. PMID:19606785

  12. Taxonomic status of Tetragonopterus anomalus Steindachner, 1891, an inquirenda species in Characidae (Teleostei: Characiformes).

    PubMed

    Carvalho, Fernando R; Santos, Ana Cláudia

    2015-01-01

    Tetragonopterus anomalus Steindachner was briefly described in July of 1891 (Steindachner 1891a:173) solely based on the holotype, which measured 144 mm (probably SL). Subsequently, in October, Steindachner (1891b:369) illustrated and redescribed the species in more detail. The type specimen was collected in the Paraná River, in the vicinity of Corrientes, Argentina. A few months before, in April of the same year, Perugia (1891:643) described Tetragonopterus nigripinnis, from de la Plata River. Ulrey (1895:273) considered T. anomalus as a junior synonym of T. nigripinnis, but did not justify the reasons for this synonymy, which was later supported by Perugia (1897:25). Eigenmann (1903:145) proposed the genus Markiana, with T. nigripinnis (= M. nigripinnis) as type species (type by monotypy), but did not mention T. anomalus in the description of this genus. However, in his later review of Markiana, Eigenmann (1918:124) confirmed T. anomalus as a junior synonym of Markiana nigripinnis, followed also by Fowler (1948:136). Nonetheless, uncertainty about the taxonomic status of T. anomalus, a poorly known species, led Lima et al. (2003:161) to consider it an inquirenda species in Characidae, and this status has been maintained until the present (Eschmeyer 2015). PMID:26624034

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

    PubMed

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

    2016-01-01

    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 12(th) endemic fish species from Trindade Island. PMID:27006618

  14. Cell types in the pituitary of the roach, Rutilus rutilus (L.), (Teleostei).

    PubMed Central

    Jafri, S I; Ensor, D M

    1980-01-01

    The pituitary of roach, Rutilus rutilus (L.), is pear-shaped and situated in the sella turcica. It is characterised by a large pars nervosa, which penetrates deep into the other regions, splitting the proximal pars distalis. Spatial localisation of nerve fibre types and glandular cell types occurs. Using a variety of staining techniques six glandular cell types have been localised and their distribution is disucssed in relation to those of the other teleost pituitaries. PMID:6159340

  15. Distribution and species composition of juvenile and adult scombropids (Teleostei, Scombropidae) in Japanese coastal waters.

    PubMed

    Itoi, S; Odaka, J; Yuasa, K; Akeno, S; Nakajima, A; Suenaga, A; Noda, T; Akimoto, S; Myojin, T; Ikeda, Y; Masuda, Y; Takai, N; Yoshihara, K; Sugita, H

    2010-02-01

    Two scombropid fishes, Scombrops boops and Scombrops gilberti, are closely related and commercially important species in Japan. These species are often confused in commercial markets because of their morphological similarity. In this study, scombropid specimens collected from various Japanese coastal waters were subjected to polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis and phylogenetic analysis of the 16S rRNA gene in mitochondrial DNA. These analyses showed that all the scombropid specimens collected from localities in the Sea of Japan were identified as S. boops, whereas those from the Pacific Ocean included two species, S. boops and S. gilberti. Almost all juvenile (<200 mm standard body length, S(L)) S. gilberti originated from the Pacific coastal waters of the northern Japan, whereas adults (>400 mm S(L)) were found only in deep water off the Izu Peninsula to the Izu Islands. This suggests that S. gilberti might migrate extensively during its life cycle. In addition, differences in the number of specimens and the distribution between the two species suggest that S. gilberti is less abundant than S. boops in Japanese waters. PMID:20738713

  16. Quantitative histological studies of the optic tectum in six species of Notropis and Cyprinella (Cyprinidae, Teleostei).

    PubMed

    Huber, R; Rylander, M K

    1991-01-01

    Significant differences in stratification and size of the visual layers of the optic tectum were found between three clear-water minnows (Notropis amabilis, N. boops, Cyprinella venustas) and three turbid-water minnows (N. atherinoides, N. bairdi, and C. lutrensis). Correlations among a variety of neural structures suggested the importance of stratum marginale (SM), stratum opticum (SO), and stratum fibrosum et griseum superficiale (SFGS), stratum griseum centrale (SGC) and stratum periventriculare (SPV) in vision, of stratum album centrale (SAC) and SGC for olfaction, and of SPV for the processing of acoustico-lateral information. PMID:1779132

  17. Spermatozoon ultrastructure of Aponurus laguncula (Digenea: Lecithasteridae), a parasite of Aluterus monoceros (Pisces: Teleostei).

    PubMed

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

    2010-03-01

    The mature spermatozoon of Aponurus laguncula, a parasite of the unicorn leatherjacket Aluterus monoceros, was studied by transmission electron microscopy. The spermatozoon possesses 2 axonemes of the 9+"1" trepaxonematan pattern, attachment zones, a nucleus, a mitochondrion, external ornamentation of the plasma membrane and cortical microtubules. The major features are the presence of: 1) external ornamentation in the anterior part of the spermatozoon not associated with cortical microtubules; 2) one mitochondrion; and 3) cortical microtubules arranged as a single field in the ventral side. The maximum number of microtubules is in the nuclear region. The extremities of the axonemes are characterized by the disappearance of the central core and the presence of microtubule doublets or singlets. This study is the first undertaken with a member of the Lecithasteridae and exemplifies the sperm ultrastructure for the superfamily Hemiuroidea. PMID:19559102

  18. Skin toxins in coral-associated Gobiodon species (Teleostei: Gobiidae) affect predator preference and prey survival

    PubMed Central

    Gratzer, Barbara; Millesi, Eva; Walzl, Manfred; Herler, Juergen

    2015-01-01

    Predation risk is high for the many small coral reef fishes, requiring successful sheltering or other predator defence mechanisms. Coral-dwelling gobies of the genus Gobiodon live in close association with scleractinian corals of the genus Acropora. Earlier studies indicated that the low movement frequency of adult fishes and the development of skin toxins (crinotoxicity) are predation avoidance mechanisms. Although past experiments showed that predators refuse food prepared with goby skin mucus, direct predator–prey interactions have not been studied. The present study compares the toxicity levels of two crinotoxic coral gobies – Gobiodon histrio, representative of a conspicuously coloured species, and Gobiodon sp.3 with cryptic coloration – using a standard bioassay method. The results show that toxin levels of both species differ significantly shortly after mucus release but become similar over time. Predator preferences were tested experimentally in an aquarium in which the two gobies and a juvenile damselfish Chromis viridis were exposed to the small grouper Epinephelus fasciatus. Video-analysis revealed that although coral gobies are potential prey, E. fasciatus clearly preferred the non-toxic control fish (C. viridis) over Gobiodon. When targeting a goby, the predator did not prefer one species over the other. Contrary to our expectations that toxic gobies are generally avoided, gobies were often captured, but they were expelled quickly, repeatedly and alive. This unusual post-capture avoidance confirms that these gobies have a very good chance of surviving attacks in the field due to their skin toxins. Nonetheless, some gobies were consumed: the coral shelter may therefore also provide additional protection, with toxins protecting them mainly during movement between corals. In summary, chemical deterrence by crinotoxic fishes seems to be far more efficient in predation avoidance than in physical deterrence involving body squamation and/or strong fin spines. PMID:26074654

  19. Macropharyngodon pakoko, a new species of wrasse (Teleostei: Labridae) endemic to the Marquesas Islands, French Polynesia.

    PubMed

    Delrieu-Trottin, Erwan; Williams, Jeffrey T; Planes, Serge

    2014-01-01

    A new species of wrasse, Macropharyngodon pakoko, is described from the Marquesas Islands, bringing the total number of species of the genus Macropharyngodon to 12. Macropharyngodon pakoko was found at depths from 0-42 m and is endemic to the Marquesas Islands. Macropharyngodon pakoko is similar to M. meleagris, which is widely distributed from the central and western Pacific to Cocos-Keeling in the Indian Ocean, but differs genetically and in several coloration characters: males with irregularly curved black humeral blotch with incomplete iridescent blue border; inverted irregular "U"- shaped band on the cheek; a small black spot at the upper base of the pectoral fin; and background color of the body greenish with faint bluish black spots on each scale. Females lack black pigment on the chest posterior to the ventral attachment of the gill membranes; reddish black blotches on the body are widely spaced, particularly on the head where they are more reddish and half the size of those on body; caudal fin with small, bright yellow spots arranged in narrow vertical bands with pale interspaces; pelvic fins pale with three reddish yellow cross-bands; a small black spot at the upper base of the pectoral fin; and small reddish spots along the base of the anal fin. Juveniles have irregular black blotches on the body, a small black spot instead of an ocellus posteriorly on the dorsal fin and lack large black spots and ocellus on the anal fin.  PMID:25283116

  20. Phylogeny and biogeography of a shallow water fish clade (Teleostei: Blenniiformes)

    PubMed Central

    2013-01-01

    Background The Blenniiformes comprises six families, 151 genera and nearly 900 species of small teleost fishes closely associated with coastal benthic habitats. They provide an unparalleled opportunity for studying marine biogeography because they include the globally distributed families Tripterygiidae (triplefin blennies) and Blenniidae (combtooth blennies), the temperate Clinidae (kelp blennies), and three largely Neotropical families (Labrisomidae, Chaenopsidae, and Dactyloscopidae). However, interpretation of these distributional patterns has been hindered by largely unresolved inter-familial relationships and the lack of evidence of monophyly of the Labrisomidae. Results We explored the phylogenetic relationships of the Blenniiformes based on one mitochondrial (COI) and four nuclear (TMO-4C4, RAG1, Rhodopsin, and Histone H3) loci for 150 blenniiform species, and representative outgroups (Gobiesocidae, Opistognathidae and Grammatidae). According to the consensus of Bayesian Inference, Maximum Likelihood, and Maximum Parsimony analyses, the monophyly of the Blenniiformes and the Tripterygiidae, Blenniidae, Clinidae, and Dactyloscopidae is supported. The Tripterygiidae is the sister group of all other blennies, and the Blenniidae is the sister group of the remaining blennies. The monophyly of the Labrisomidae is supported with the exclusion of the Cryptotremini and inclusion of Stathmonotus, and we elevate two subgenera of Labrisomus to establish a monophyletic classification within the family. The monophyly of the Chaenopsidae is supported with the exclusion of Stathmonotus (placed in the Stathmonotini) and Neoclinus and Mccoskerichthys (placed in the Neoclinini). The origin of the Blenniiformes was estimated in the present-day IndoPacific region, corresponding to the Tethys Sea approximately 60.3 mya. A largely Neotropical lineage including the Labrisomidae, Chaenopsidae and Dactyloscopidae (node IV) evolved around 37.6 mya when the Neotropics were increasingly separated from the IndoPacific, but well before the closure of the Tethys Sea. Conclusions Relationships recovered in this study are similar to those of earlier analyses within the Clinidae and Chaenopsidae, and partially similar within the Blenniidae, but tripterygiid relationships remain poorly resolved. We present the first comprehensive phylogenetic hypothesis for a monophyletic Labrisomidae with five tribes (Labrisomini, Mnierpini, Paraclinini, Stathmonotini and Starksiini). Global distributions of blenny genera included in our analysis support the evolution of a largely Neotropical clade whose closest relatives (clinids and cryptotremines) are temperate in distribution. PMID:24067147

  1. The complete mitochondrial genome sequence of Triplophysa anterodorsalis (Teleostei, Balitoridae, Nemacheilinae).

    PubMed

    Que, Yan-fu; Liao, Xiao-lin; Xu, Dong-mei; Yang, Zhi; Tang, Hui-yuan; Zhu, Bin

    2016-01-01

    Triplophysa anterodorsalis is an endemic fish in the upper stream of the Yangtze River, Jinsha River and its tributaries. However, wild populations of T. anterodorsalis declined sharply due to cascade hydropower stations constructed successively in the Jinsha River during the past decades. In the present study, the complete mitochondrial DNA genome sequence of T. anterodorsalis was first determined by DNA sequencing based on the PCR fragments. The complete mitochondrial genome sequence of T. anterodorsalis is a circular molecule of 16,567 bp in size. It consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a control region (D-loop). The gene nucleotide composition of T. anterodorsalis is 27.37% A, 25.68% C, 18.37% G, and 28.57% T, with a relatively a relatively high A + T content (55.94%). The results could provide useful data for studies on genetic structure and diversity and rational resource conservation in T. anterodorsalis. PMID:24919506

  2. Structure and function of placental exchange surfaces in goodeid fishes (Teleostei: Atheriniformes).

    PubMed

    Schindler, Joachim F

    2015-08-01

    The species of the family Goodeidae have evolved reproductive strategies involving intraovarian gestation, early evacuation of nearly yolk-exhausted embryos from the ovigerous tissue into the ovarian cavity, placental matrotrophy during intraluminal gestation, and the birth of highly developed fry. The inner ovarian lining becomes hypervascularized during gestational periods and functions as the maternal component of the placental association. Embryotrophic liquid is secreted by the inner ovarian epithelium into the ovarian cavity. Comparative electrophoretic analyses of embryotrophe and maternal blood serum provide evidence for the transfer of maternal serum proteins into the embryotrophe. Trophotaeniae, proctodaeal processes of the embryos, provide a surface for nutrient absorption. Endocytic activity was demonstrated by ingestion of unspecific tracer proteins in various species. Moreover, the trophotaenial absorptive cells (TACs) in Ameca splendens ingest various proteins or random copolymers conjugated to colloidal gold as well as radioiodinated proteins in a way that satisfies the criteria of receptor-mediated endocytosis. Several aminopeptidases (APs) on the surface of TACs were identified as protein binding sites as evidenced by inhibition of binding and uptake of marker proteins in the presence of AP substrates or AP inhibitors. Morphological adaptations of the embryonic circulatory system pertaining to nutrient and gas exchange were characterized. The embryonic epidermis comprises two layers of squamous cells closely underlain by a dense capillary net. Efficient gas exchange is facilitated by a thin embryotrophe-blood barrier of both the embryonic skin and the intraovarian lining. PMID:24797516

  3. 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

  4. 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. PMID:23912195

  5. 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. PMID:24186153

  6. 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. PMID:26913945

  7. Phylogenetic position of Scombropidae within teleostei: the complete mitochondrial genome of the gnomefish, Scombrops gilberti.

    PubMed

    Tsunashima, Tadasuke; Yamada, Riko; Abe, Koko; Noguchi, Shunsuke; Itoi, Shiro; Nakai, Shizuko; Takai, Noriyuki; Sugita, Haruo

    2016-09-01

    The complete mitochondrial genome of the Japanese gnomefish, Scombrops gilberti, was determined using a PCR-based method. The total length of mitochondrial DNA (mtDNA) is 16 518 bp, which includes 13 protein-coding genes, two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and one control region. The mitochondrial gene arrangement of S. gilberti was found to be identical to that of other scombropid and indeed, other teleosts as well. Maximum likelihood analysis revealed that Scombropidae forms a sister group to Pempheriformes. PMID:26153741

  8. The structure and ultrastructure of the rostral cartilage in the spiny eel, Macrognathus siamensis (Teleostei: Mastacembeloidei).

    PubMed Central

    Benjamin, M; Sandhu, J S

    1990-01-01

    An elastic, cell-rich cartilage provides flexible support to the highly mobile, rostral tentacle of the mastacembelid, Macrognathus siamensis. Active movement of the tentacle is effected by skeletal muscles, the muscular bellies of which are located outside the organ. The tentacle returns to its original shape by elastic recoil. The cartilage resembles plant supporting tissue and the cartilages of certain invertebrates. It is surrounded by a thick perichondrium and articulates at a synovial joint with the supraethmoid. The chondrocytes are large and shrunken within lacunae. They contain glycogen and cytoplasmic stores of RNA. The matrix is reduced to thin seams between adjacent cells, and stains strongly with alcian blue and a variety of elastic stains. Parts of the matrix are trilaminar, and such an appearance recalls the distinction between the primary cell walls of adjacent plant cells and the intervening middle lamella. The perichondrium consists of an alternating sequence of cells, circularly arranged collagen fibres and a foamy, amorphous material of unknown composition. Deep to the perichondrium, the chondrocytes are packed with intermediate filaments. Membrane-bound organelles are not prominent, though mitochondria are located at the periphery of the cell. The ultrastructural similarities between these chondrocytes and those of hyaline-cell cartilage (chondroid) support the contention that Schaffer's concept of a rigid distinction between 'true' cartilage and 'chondroid' is no longer tenable. The matrix is devoid of collagen and is most distinctive. In the immediate vicinity of the cells it consists of matrix granules and matrix fibers but, where a trilaminar appearance is easily discernible, there is a central zone that consists of large masses of amorphous material that is presumed to contain elastin. Such amorphous material has not previously been seen in any teleostean elastic tissue. By contrast, elastic system fibres, readily demonstrable elsewhere in teleosts, are conspicuously absent. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 PMID:1696572

  9. 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. PMID:25517538

  10. 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

  11. 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

    2015-01-01

    The hill-stream loach genus Nemachilichthys, an endemic of the Western Ghats of India, comprises two nominal species, N. rueppelli and N. shimogensis. The validity of the latter has been questioned by several authors. Here we show that there is only a marginal raw mitochondrial genetic distance (0.5% in cytochrome oxidase subunit I and 1.2% in cytochrome b) between topotypic specimens of the two nominal species. Further, although population-level morphometric variations appear in a multivariate morphometric analysis, the two nominal species are morphologically similar, with apparently no significant characters separating them. We therefore consider N. shimogensis to be a junior synonym of N. rueppelli and redescribe the latter, providing further details on population variation and distribution. PMID:26701578

  12. 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. PMID:26452303

  13. 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

  14. The structure and ultrastructure of the rostral cartilage in the spiny eel, Macrognathus siamensis (Teleostei: Mastacembeloidei).

    PubMed

    Benjamin, M; Sandhu, J S

    1990-04-01

    An elastic, cell-rich cartilage provides flexible support to the highly mobile, rostral tentacle of the mastacembelid, Macrognathus siamensis. Active movement of the tentacle is effected by skeletal muscles, the muscular bellies of which are located outside the organ. The tentacle returns to its original shape by elastic recoil. The cartilage resembles plant supporting tissue and the cartilages of certain invertebrates. It is surrounded by a thick perichondrium and articulates at a synovial joint with the supraethmoid. The chondrocytes are large and shrunken within lacunae. They contain glycogen and cytoplasmic stores of RNA. The matrix is reduced to thin seams between adjacent cells, and stains strongly with alcian blue and a variety of elastic stains. Parts of the matrix are trilaminar, and such an appearance recalls the distinction between the primary cell walls of adjacent plant cells and the intervening middle lamella. The perichondrium consists of an alternating sequence of cells, circularly arranged collagen fibres and a foamy, amorphous material of unknown composition. Deep to the perichondrium, the chondrocytes are packed with intermediate filaments. Membrane-bound organelles are not prominent, though mitochondria are located at the periphery of the cell. The ultrastructural similarities between these chondrocytes and those of hyaline-cell cartilage (chondroid) support the contention that Schaffer's concept of a rigid distinction between 'true' cartilage and 'chondroid' is no longer tenable. The matrix is devoid of collagen and is most distinctive. In the immediate vicinity of the cells it consists of matrix granules and matrix fibers but, where a trilaminar appearance is easily discernible, there is a central zone that consists of large masses of amorphous material that is presumed to contain elastin. Such amorphous material has not previously been seen in any teleostean elastic tissue. By contrast, elastic system fibres, readily demonstrable elsewhere in teleosts, are conspicuously absent. PMID:1696572

  15. 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

  16. Intersexuality of Scomberomorus niphonius from the Coastal Area around Jeju Island, Korea (Teleostei: Scombridae)

    PubMed Central

    Kim, Jong Bin; Chang, Dae Soo; Kim, Hyejin; Jeon, Mi Ae; Ku, Kayeon; Lee, Jung Sick

    2013-01-01

    This study histologically describes the intersexuality of Scomberomorus niphonius collected from the coastal area near Jeju Island. A total of 126 S. niphonius, collected from March to July 2012 with a total length of 62.4 cm (17.5) and a total weight of 1,701.9 g (1,528.9) were used for analyses. From a histological perspective, two types of intersex were confirmed. One type had scattered germ cells from the opposite sex within the gonad. The second type developed germ cells from the opposite sex in the connective tissue of the outer gonadal membrane. The intersexuality was 14.3% (n=18/126), with females (21.3%; n=16/75) exhibiting a higher rate than males (3.9%; n=2/51). There was no displayed correlation between intersexuality and the total length and weight. PMID:25949123

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

    PubMed

    Silva, Rodet Rodriguez

    2015-01-01

    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. PMID:25947808

  18. Callionymus omanensis, a new species of dragonet from Oman, north-western Indian Ocean (Teleostei: Callionymidae).

    PubMed

    Fricke, R; Jawad, L A; Al-Mamry, J M

    2014-11-01

    A new species of deep-living dragonet Callionymus omanensis from Oman is described on the basis of a single male specimen collected in a trawl from 500 m depth off the coast of Oman. The new species is characterized within the subgenus Bathycallionymus by having a small branchial opening; head short (3·9 in proportion to standard length); eye large (2·4 in proportion to head length); preopercular spine with a long, upcurved main tip, with a small antrorse barb and a larger antrorse spine, and with a strong antrorse spine laterally at the preopercular-spine base, ventral margin smooth; first dorsal fin slightly higher than second dorsal fin (male); second dorsal fin distally straight; 17 pectoral fin rays; distal end of caudal fin slightly pointed, with two median unbranched rays bearing short filaments; first dorsal fin with basal black spot reaching from first to fourth membranes, third membrane with an ocellated distal black blotch; second dorsal fin with vertical dark grey bars; distal three-fourths of anal fin black; upper half of caudal fin with oblique dark grey bars; pelvic fin dark grey, second ray basally with a black blotch. The new species is compared with similar species. Revised keys to callionymid species of the western Indian Ocean and the Red Sea, as well as species of the subgenus Bathycallionymus, are presented. PMID:25098471

  19. Morphometric studies of genus Placocheilus (Teleostei: Cypriniformes) from Red River, China

    PubMed Central

    ZHOU, Wei; LI, Min-hui; WANG, Chun-ping; QI, Mi

    2015-01-01

    It is practically difficult to differentiate Placocheilus robustus and Placocheilus caudofasciatus from Red River drainage of China. Without stated reasons, P. robustus has been assumed as the synonyms of P. caudofasciatus. The present study aims to decipher the morphological differences between two species so as to provide reliable clues for their classification by multivariate morphometry. A total of 72 specimens of two species in genus Placocheilus were examined. Besides morphological character comparisons, 10 anatomic landmarks were utilized and 23 frame structures and 15 general characters measured. The scatter plot results of principal component analysis showed that all specimens were clustered together and could not be defined as two distinct species. No significant morphological differences existed in four diagnostic characters between P. robustus and P. caudofasciatus. Thus the results of the present study fail to support P. robustus as a valid and independent species. PMID:26646572

  20. 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. PMID:26443385

  1. Gonadal morphogenesis and sex differentiation in the viviparous fish Chapalichthys encaustus (Teleostei, Cyprinodontiformes, Goodeidae).

    PubMed

    Guerrero-Estvez, S; Moreno-Mendoza, N

    2012-03-01

    This study describes the structural and ultrastructural characteristics of gonadal sex differentiation and expression of Vasa, a germline marker, in different developmental stages of embryos and newborn fry of the barred splitfin Chapalichthys encaustus, a viviparous freshwater teleost endemic to Mexico. In stage 2 embryos, the gonadal crest was established; gonadal primordia were located on the coelomic epithelium, formed by scarce germ and somatic cells. At stage 3, the undifferentiated gonad appeared suspended from the mesentery of the developing swimbladder and contained a larger number of germ and somatic cells. At stages 4 and 5, the gonads had groups of meiotic and non-meiotic germ cells surrounded by somatic cells; meiosis was evident from the presence of synaptonemal complexes. These stages constituted a transition towards differentiation. At stage 6 and at birth, the gonad was morphologically differentiated into an ovary or a testis. Ovarian differentiation was revealed by the presence of follicles containing meiotic oocytes, and testicular differentiation by the development of testicular lobules containing spermatogonia in mitotic arrest, surrounded by Sertoli cells. Nuage, electron-dense material associated with mitochondria, was observed in germ cells at all gonadal stages. The Vasa protein was detected in all of the previously described stages within the germ-cell cytoplasm. This is the first report on morphological characteristics and expression of the Vasa gene during sexual differentiation in viviparous species of the Goodeidae family. Chapalichthys encaustus may serve as a model to study processes of sexual differentiation in viviparous fishes and teleosts. PMID:22380554

  2. The phylogenetic placement of Hollandichthys Eigenmann 1909 (Teleostei: Characidae) and related genera.

    PubMed

    Thomaz, Andréa T; Malabarba, Luiz R; Bonatto, Sandro L

    2010-12-01

    The phylogenetic relationships among characids are complex with many genera remaining of uncertain systematic position inside the family. The genus Hollandichthys is one of these problematic genera. It has been considered as incertae sedis inside this family until two recently published phylogenies, one morphological and one molecular, arrived at alternative hypothesizes as to the relationships of Hollandichthys with Pseudochalceus or Rachoviscus, respectively. In this paper, we infer the phylogenetic relations of these taxa based on five genes (three mitochondrial - COI, ND2 and 16S; and two nuclear - Sia and Trop), totaling up to 2719 bp. The 41 analyzed species in the Characidae include four incertae sedis characid taxa once hypothesized as related to Hollandichthys, but never analyzed in a single phylogeny (Rachoviscus, Pseudochalceus, Nematocharax and Hyphessobrycon uruguayensis). Here we propose Rachoviscus as the sister-group of Hollandichthys, grouped in the large clade C previously defined, along with the remaining incertae sedis taxa studied here. In addition, we support the evidence that insemination evolved independently at least three times in the Characidae. PMID:20965264

  3. 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. PMID:25982049

  4. Pethia sanjaymoluri, a new species of barb (Teleostei: Cyprinidae) from the northern Western Ghats, India.

    PubMed

    Katwate, U; Jadhav, S; Kumkar, P; Raghavan, R; Dahanukar, N

    2016-05-01

    Pethia sanjaymoluri, a new cyprinid, is described from the Pavana and Nira tributaries of Bhima River, Krishna drainage, Maharashtra, India. It can be distinguished from congeners by a combination of characteristics that includes an incomplete lateral line, absence of barbels, upper lip thick and fleshy, 23-25 lateral series scales, 7-12 lateral-line pored scales, 10 predorsal scales, 11-14 prepelvic scales, 17-20 pre-anal scales, 4½ scales between dorsal-fin origin and lateral line, four scales between lateral line and pelvic-fin origin, 8-15 pairs of serrae on distal half of dorsal-fin spine, 12-14 branched pectoral-fin rays, 4 + 26 total vertebrae, 4 + 5 predorsal vertebrae, 4 + 13 abdominal vertebrae, 13 caudal vertebrae and a unique colour pattern comprising a humeral spot positioned below the lateral line and encompassing the third and fourth lateral-line scales and one scale below, one caudal spot on 17th-21st lateral-line scales with a yellow hue on its anterior side and apical half of dorsal fin studded with melanophores making the fin tip appear black. Genetic analysis based on the mitochondrial cytochrome b gene sequence suggests that the species is distinct from other known species of Pethia for which data are available. PMID:27098090

  5. Acute effects of cadmium on the spot Leiostomus xanthurus (teleostei): tissue distribution and renal ultrastructure

    SciTech Connect

    Hawkins, W.E.; Tate, L.G.; Sarphie, T.G.

    1980-03-01

    Spot (Leiostomus xanthurus) was exposed to 1, 5, 10, 15, and 25 ppM cadmium chloride for 48 h. Analysis by atomic absorption spectrophotometry showed that cadmium accumulated mainly in the liver, followed by heart, gut, kidney, and gill. Brain and body muscle did not concentrate the metal. Electron microscopy showed that the proximal tubule cells were severely affected by cadmium levels of 10, 15, and 25 ppM. The proximal tubule cells exhibited responses that ranged from an increase in heterogeneous bodies to epithelial desquamation. Mitochondria of degenerating proximal tubule cells showed changes similar to metal-poisoned mammalian kidney cells. Some mitochondria were contracted and dense while others were swollen with granular matrices and focal electron densities. In exposures of 25 ppM, Bowman's space of the renal corpuscle was swollen and often contained cellular debris. This study showed that after acute exposure to cadmium the metal accumulated mainly in visceral organs of the spot and at levels of 10 ppM and greater resulted in severe damage to proximal tubule cells of the kidney.

  6. Phylogenetic relationships and natural hybridization in rabbitfishes (Teleostei: Siganidae) inferred from mitochondrial and nuclear DNA analyses.

    PubMed

    Kuriiwa, Kaoru; Hanzawa, Naoto; Yoshino, Tetsuo; Kimura, Seishi; Nishida, Mutsumi

    2007-10-01

    Phylogenetic relationships of rabbitfishes (the family Siganidae), ecologically important components as primary consumers in coral reef communities, were studied using mitochondrial cytochrome b gene and nuclear ITS1 (internal transcribed spacer 1) sequence analyses. The analyses of 19 out of 22 species known in the Western Pacific region revealed that siganids are genetically clustered into three major clades, which are characterized by some morphological and ecological traits. Between closely related species, such as Siganus guttatus-S. lineatus and S. virgatus-S. doliatus, and also between two morphs recognized in S. corallinus, small but discernible genetic differentiation was found, implying that the components of each pair are incipient species. On the other hand, between some species, such as S. fuscescens-S. canaliculatus and S. unimaculatus-S.vulpinus, individuals of the components of each pair were found to construct a genetic mosaic, suggesting that the components are genetic color morphs within a single biological species, respectively. Moreover, evidence from morphological characters, mtDNA, and nuclear DNA gave an inconsistent picture of identity and relationships for several individuals. They were regarded as hybrids or individuals with hybrid origin. Such instances were observed not only between closely related species, such as S. guttatus-S. lineatus, S. virgatus-S. doliatus, and two morphs (incipient species) in S. corallinus, respectively, but also between distantly related ones, such as S. corallinus-S. puellus. In fact, more than half of the species examined (11/20, when treating the two morphs in S. corallinus as independent species) were involved in hybridization. These suggest that hybridization is much more prevalent in marine fishes than previously assumed, and may have some relevance to their diversification. PMID:17590356

  7. 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

  8. The complete mitochondrial genome organization of Schizothorax Plagiostomus (Teleostei: Cyprinidae) from Northern Pakistan.

    PubMed

    Fiaz Khan, Muhammad; Nasir Khan Khattak, Muhammad; He, Dekui; Liang, Yangyang; Li, Chunhua; Ullah Dawar, Farman; Chen, Yifeng

    2016-09-01

    Schizothorax plagiostomus, a fresh water fish, is an economically important fish of Pakistan. In this study, the complete mitochondrial DNA (mtDNA) sequence of S. plagiostomus was explored. The mitogenome length was found to be 16 563bp with 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 2 non-coding regions: origin of light-strand replication (OL) and control region (D-loop). All genes were encoded on the heavy strand except ND6 and few tRNA genes. The overall base composition of S. plagiostomus of the heavy strand was T 25.5%, C 27.0%, A 29.8% and G 17.8%, A + T content 55.3% and G + C content 44.7%. The phylogenetic tree suggests that S. esocinus, S. progastus, S. richardsonii and S. plagiostomus may have closer affinities than other fish of the genus Schizothorax. This mitogenome sequence would be useful for phylogenetic analysis and conservation of this species in Pakistan. PMID:26369352

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

    PubMed

    Hastings, Philip A; Findley, Lloyd T

    2015-01-01

    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.  PMID:25660803

  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. 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.

  12. Observations on the reproductive and larval biology of Blennius pavo (Pisces: Teleostei)

    NASA Astrophysics Data System (ADS)

    Westernhagen, H.

    1983-09-01

    Social behaviour and spawning of adult Blennius pavo kept in the laboratory are described. Eggs are deposited in batches on the walls of artificial spawning places (PVC pipes). One male guards and tends the eggs of different females in one spawning place. Larval hatching occurs in groups according to oviposition. Minimum incubation temperature is around 14 15°C. Larval survival in 1-1 rearing jars is not related to larval total length but to density of larval stock. An experimental population of laboratory reared juvenile and adolescent B. pavo displays a male to female ratio of 1:1.4. Factors possibly influencing the sex ratio of this littoral fish are discussed in view of the situation in its natural environment.

  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. PMID:23431379

  14. Diplectanocotyla Yamaguti, 1953 (Monogenea: Diplectanoidea) from Megalops cyprinoides (Broussonet) (Teleostei: Megalopidae) off Peninsular Malaysia.

    PubMed

    Lim, L H S; Gibson, D I

    2007-06-01

    Two known and two new species of Diplectanocotyla Yamaguti, 1953 (D. gracilis Yamaguti, 1953, D. megalopis Rakotofiringa & Oliver, 1987, D. langkawiensis n. sp. and D. parva n. sp.) were collected from Megalops cyprinoides (Megalopidae) off Langkawi, Kedah and Matang, Perak, Peninsular Malaysia. All four species possess similar types of sclerotised male and female reproductive structures and similar soft anatomical features. The squamodisc sclerites of all four species have spine-like projections with varying degrees of visibility and shapes (sharp-pointed to triangular). In D. megalopis and D. langkawiensis n. sp. the spines are sharp-pointed and distinct on sclerites from rows 5-6 onwards. In D. gracilis and D. parva n. sp. the sclerite spines are triangular, lightly sclerotised and occur on almost all of the sclerites. D. parva n. sp. has comparatively the smallest set of anchors, bars, squamodiscs and squamodisc suckers. The anchors and bars of the other three species are almost similar in overall size, and the main distinguishing feature is the relative lengths of the inner and outer roots of the ventral anchors. In D. gracilis the outer root is very much smaller than the inner root and they are disposed almost at a right angle to each other. In D. megalopis the outer root is usually about half the length of the inner root and the roots are inclined at c.60 degrees to each other. In D. langkawiensis n. sp. the roots are inclined at c.40 degrees degrees and the outer root is of a similar length or only slightly shorter than the inner root. The openings of the two squamodisc suckers of all four Diplectanocotyla species are surrounded by tiny scale-like spines. Bifid tegumental spines are found in the posterior region of all four species, differing only in their extent: in D. parva n. sp. the tegumental spines are only distributed in the peduncular region and not beyond, whilst in the other three species the tegumental spines extend from the posterior level of the testis to the end of the peduncle. An amended diagnosis of Diplectanocotyla and a key to its species are appended. PMID:17143570

  15. Complete mitochondrial genome of the Chinese lizard gudgeon, Saurogobio dabryi (Teleostei: Cypriniformes: Cyprinidae).

    PubMed

    Xu, Hao; Xue, Yang; Li, Xin-yue; Luo, Xi; Li, Yang; Li, Yun

    2015-01-01

    The Chinese lizard gudgeon, Saurogobio dabryi Bleeker, belongs to the subfamily Gobioninea, which is an economic fish widely distributed in East Asia. In this study, we sequenced the complete mitochondrial genome of the S. dabryi. The complete mitogenome was 16,601 bp in size, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and 1 control region. It has the typical circular molecule structure of vertebrate's mitochondrial genome. The whole base composition was estimated to be 29.64%A, 26.47%T, 27.06%C and 16.83%G with AT bias of 56.11%. This study is a first report the complete mitogenome of S. dabryi and provides the basis for preservation of genetic resources and phylogenetic analyses on this species. PMID:24409846

  16. 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

  17. 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

  18. 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

  19. New approach data in electric fish (Teleostei: Gymnotus): sex chromosome evolution and repetitive DNA.

    PubMed

    da Silva, Maelin; Matoso, Daniele Aparecida; Artoni, Roberto Ferreira; Feldberg, Eliana

    2014-12-01

    Antagonist sexual selection is the driving force behind the origin and diversification of sex chromosomes such as XX/XY and ZZ/ZW. However, chromosome mobility, mainly in fishes, may result in the formation of chromosomes of recent origin, a process known as turnover. The family Gymnotidae, which is composed of the genera Electrophorus+Gymnotus, presents a multiple system of the type X1X1X2X2/X1X2Y, which has been described for Gymnotus pantanal. This article describes the karyotype of three Amazon Gymnotus species, revealing the presence of both simple and multiple systems: Gymnotus carapo "Catalão" 2n=40 XX/XY, Gymnotus coropinae 2n=49♂/50♀ X1X1X2X2/X1X2Y, and Gymnotus sp. "Negro" 2n=50 XX/XY. Our hypothesis is that the simple system present in G. carapo "Catalão" is ancestral in relation to G. pantanal's multiple system and that the diversification of the subsequent multiple system occurred after the final separation of the Amazon and Paraná basins. Moreover, G. coropinae's multiple system may have originated from the simple system present in Gymnotus sp. "Negro." The distant position between the species in the Gymnotidae family's phylogeny in addition to differences in sex chromosome formula and number between Clade G1 G. coropinae and G. sp. "Negro" species and "Carapo" Clade. G. carapo and G. pantanal species suggest that both sequences of sexual systems occurred independently, supporting other proposed models and highlighting the fact that species of the genus Gymnotus may serve as a model for studying sex chromosome turnover. PMID:25264714

  20. Four new species of Rasbora of the Sumatrana group (Teleostei: Cyprinidae) from northern Sumatra, Indonesia.

    PubMed

    Lumbantobing, Daniel N

    2014-01-01

    Four new species of the minnow genus Rasbora of the Sumatrana group, R. arundinata, R. haru, R. maninjau, and R. bindumatoga, are described from northern Sumatra. Rasbora arundinata is distinguished from all congeners in the Sumatrana group by the black midlateral stripe overall forming a reed-leaf-like profile. Rasbora haru differs from its congeners in the Sumatrana group in having the black midlateral stripe overall forming a stamen-like profile. The new species endemic to Lake Maninjau in central west Sumatra, Rasbora maninjau, is unique among all the congeners in the Sumatrana group in having a combination of the black midlateral stripe extending from the midhumeral region of uniform width, the prominent acutely triangular basicaudal blotch, and the oval supra-anal pigmentation. Rasbora bindumatoga is distinguished from all congeners in the Sumatrana group by a combination of the black rectangular subdorsal blotch, the absence of supra-anal pigmentation, and the somewhat oval basicaudal blotch. Rasbora arundinata, R. maninjau, and R. bindumatoga occur allopatrically in the northwestern coastal region of Sumatra, while R. haru is known from northeastern coastal area of Sumatra. A new diagnostic character for the Sumatrana group is described: partial exposure of the upper lip due to a submedial contact between the maxilla and the lower lip, which is marked posteriorly by a lachrymal groove.  PMID:24870277

  1. Lake Tanganyika--a 'melting pot' of ancient and young cichlid lineages (Teleostei: Cichlidae)?

    PubMed

    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. Complete mitochondrial genome of copperband butterflyfish Chelmon rostratus (Teleostei, Perciformes, Chaetodontidae).

    PubMed

    Wang, Li-Juan; You, Feng; Wu, Zhi-Hao

    2016-05-01

    In this study, the complete mitochondrial (mt) genome of the copperband butterflyfish Chelmon rostratus from Beibu Bay, China, was determined. It is one of the most common coral reef fish in South China Sea. The total length of C. rostratus mitogenome is 16,538 bp, which consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and a control region, with the genome organization and gene order being identical to other typical vertebrate mitogenomes. The overall nucleotide composition of the H-strand is 28.05% A, 28.94% T, 16.22% G and 26.79% C, with an A + T bias. This study will provide the first complete mitochondrial genome of Chelmon rostratus as useful information for the application of fish phylogenetic relationship analysis within the butterflyfish species. PMID:25427816

  3. 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. PMID:24269211

  4. Genetic admixture of burbot (Teleostei: Lota lota) in Lake Constance from two European glacial refugia.

    PubMed

    Barluenga, Marta; Sanetra, Matthias; Meyer, Axel

    2006-10-01

    The burbot, Lota lota, is the only freshwater species of the codfish family and has a Holarctic distribution. Pleistocene glaciations caused significant geographical differentiation in the past, but its life history characterized by winter spawning migrations over large distances is likely to homogenize populations by contemporary gene flow. We investigated the population genetic structure of 541 burbots from Lake Constance and adjacent Rhine and Danube tributaries in Europe using the entire mitochondrial DNA (mtDNA) control region and 11 microsatellites. Microsatellites revealed considerable population divergence (F(ST) = 0.26) and evidenced recent bottlenecks in two Central European rivers. In accordance to previous evidence two main phylogeographic lineages (Atlantic and Danubian) were found co-occurring at similar frequencies in Lake Constance, where they currently undergo random mating as indicated by microsatellites. The Danubian lineage contributed only a small proportion to the lake's mtDNA diversity, and probably expanded within the lake shortly after its formation approximately 10,000-15,000 BP. The larger Atlantic haplotype diversity suggested a population expansion older than the lake itself. Levels of admixture at microsatellite loci were less obvious due to their high variability, and coalescence methods were used to estimate past admixture proportions. Our results reinforce a model of a two-step colonization of Europe by burbot from an ancestral Danubian refuge, and confirm the persistence of a secondary Atlantic refuge, as proposed to exist for other freshwater fish. We conclude that the present-day burbot population in Lake Constance bears the genetic signature of both contemporary gene flow and historical separation events. PMID:17032259

  5. 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. 

  6. Shape based assignment tests suggest transgressive phenotypes in natural sculpin hybrids (Teleostei, Scorpaeniformes, Cottidae)

    PubMed Central

    Nolte, Arne W; Sheets, H David

    2005-01-01

    Background Hybridization receives attention because of the potential role that it may play in generating evolutionary novelty. An explanation for the emergence of novel phenotypes is given by transgressive segregation, which, if frequent, would imply an important evolutionary role for hybridization. This process is still rarely studied in natural populations as samples of recent hybrids and their parental populations are needed. Further, the detection of transgressive segregation requires phenotypes that can be easily quantified and analysed. We analyse variability in body shape of divergent populations of European sculpins (Cottus gobio complex) as well as natural hybrids among them. Results A distance-based method is developed to assign unknown specimens to known groups based on morphometric data. Apparently, body shape represents a highly informative set of characters that parallels the discriminatory power of microsatellite markers in our study system. Populations of sculpins are distinct and "unknown" specimens can be correctly assigned to their source population based on body shape. Recent hybrids are intermediate along the axes separating their parental groups but display additional differentiation that is unique and coupled with the hybrid genetic background. Conclusion There is a specific hybrid shape component in natural sculpin hybrids that can be best explained by transgressive segregation. This inference of how hybrids differ from their ancestors provides basic information for future evolutionary studies. Furthermore, our approach may serve to assign candidate specimens to their source populations based on morphometric data and help in the interpretation of population differentiation. PMID:15987531

  7. Molecular phylogeny and evolution of Scomber (Teleostei: Scombridae) based on mitochondrial and nuclear DNA sequences

    NASA Astrophysics Data System (ADS)

    Cheng, Jiao; Gao, Tianxiang; Miao, Zhenqing; Yanagimoto, Takashi

    2011-03-01

    A molecular phylogenetic analysis of the genus Scomber was conducted based on mitochondrial (COI, Cyt b and control region) and nuclear (5S rDNA) DNA sequence data in multigene perspective. A variety of phylogenetic analytic methods were used to clarify the current taxonomic Classification and to assess phylogenetic relationships and the evolutionary history of this genus. The present study produced a well-resolved phylogeny that strongly supported the monophyly of Scomber. We confirmed that S. japonicus and S. colias were genetically distinct. Although morphologically and ecologically similar to S. colias, the molecular data showed that S. japonicus has a greater molecular affinity with S. australasicus, which conflicts with the traditional taxonomy. This phylogenetic pattern was corroborated by the mtDNA data, but incompletely by the nuclear DNA data. Phylogenetic concordance between the mitochondrial and nuclear DNA regions for the basal nodes Supports an Atlantic origin for Scomber. The present-day geographic ranges of the species were compared with the resultant molecular phylogeny derived from partition Bayesian analyses of the combined data sets to evaluate possible dispersal routes of the genus. The present-day geographic distribution of Scomber species might be best ascribed to multiple dispersal events. In addition, our results suggest that phylogenies derived from multiple genes and long sequences exhibited improved phylogenetic resolution, from which we conclude that the phylogenetic reconstruction is a reliable representation of the evolutionary history of Scomber.

  8. Dario kajal, a new species of badid fish from Meghalaya, India (Teleostei: Badidae).

    PubMed

    Britz, Ralf; Kullander, Sven O

    2013-01-01

    Dario kajal, new species, is described from Seinphoh stream in the Jaintia Hills of Meghalaya, India. It can be distinguished from all other congeners by the presence of a postorbital stripe that continues behind the eye in line with the preorbital stripe and by the presence in males of a series of double bars restricted to the upper half of the body. The discovery of D. kajal in the Meghna River drainage raises the number of Dario species to five and raises interesting questions about the biogeography of the genus. PMID:25277575

  9. Dario huli, a new species of badid from Karnataka, southern India (Teleostei: Percomorpha: Badidae).

    PubMed

    Britz, Ralf; Ali, Anvar

    2015-01-01

    Dario huli, new species, is described from a small tributary stream of the Tunga River in southern Karnataka, India. It can be distinguished from all its congeners except D. urops by the presence of a conspicuous black caudal-fin blotch and by anterior dorsal-fin lappets in males not being produced beyond fin spines. It is readily distinguished from Dario urops by the absence of the horizontal suborbital stripe (vs. presence), the presence of a series of up to eight black bars on the body (vs. 2-3 black bars restricted to caudal peduncle), 25 scales in a lateral row (vs. 28), 3-5 tubed lateral-line scales (vs. tubed lateral-line scales completely absent), 13+13=26 vertebrae (vs. 14+14-15=28-29), and the presence of teeth on hypobranchial 3 (vs. absence of teeth).  PMID:25661602

  10. 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

  11. 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

  12. Descriptions of three new species of Marcusenius Gill, 1862 (Teleostei: Mormyridae) from South Africa and Mozambique.

    PubMed

    Maake, Pholoshi A; Gon, Ofer; Swartz, Ernst R

    2014-01-01

    Morphological and genetic studies of mormyrid fishes belonging to the genus Marcusenius from South Africa and Mozambique revealed four species of which three are described as new. Marcusenius pongolensis is widespread throughout the Incomati, Pongola and Kosi river systems, and sparsely represented in the Limpopo River system in South Africa. Marcusenius krameri sp. nov. is endemic to the Limpopo River system, and is the sister taxon of M. caudisquamatus sp. nov. from the Nseleni and Mhlatuze river systems in the KwaZulu-Natal Province of South Africa. The Ruvuma specimens were well differentiated from all southern and eastern African species of Marcusenius, and are therefore recognised as M. lucombesi sp. nov. Phylogenetic analysis of the mitochondrial cytochrome b gene showed that the three new species and M. altisambesi form a monophyletic lineage that is sister to a group containing M. pongolensis and M. macrolepidotus. Marcusenius krameri and M. lucombesi seems to prefer slow flowing reaches of rivers, whereas M. pongolensis and M. caudisquamatus seems to mainly inhabit rapid flowing sections of rivers with a rocky substrate. A key to the southern African species of Marcusenius is provided. PMID:24871846

  13. 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

  14. Allopolyploidization is not so simple: evidence from the origin of the tribe Cyprinini (Teleostei: Cypriniformes).

    PubMed

    Ma, W; Zhu, Z-H; Bi, X-Y; Murphy, R W; Wang, S-Y; Gao, Y; Xiao, H; Zhang, Y-P; Luo, J

    2014-01-01

    The identification of allopolyploidization events benefits from molecular dating and divergence assessments of progenitor genomes. Information on gene duplications only, either orthologs or paralogs, provides incomplete information. Analyses of mitochondrial DNA yield insights into matrilineal history, which may differ from patrilineal evolution. Two important food and pet fishes, the common carp (Cyprinus carpio) and goldfish (Carassius sp.), appear to have experienced allotetraploidization sometime from 12 to 20 million years ago (Ma). However, much work is necessary to detail the initial polyploidization event. Herein, we use this group of fishes as a model system to investigate competing scenarios for allopolyploidization. We analyze both the nuclear genes encoding growth hormone (GH), recombination activating protein 1 (RAG1) and HOXA2B gene, and the maternal heredited 12 concatenated mitochondrial protein-coding gene in 19 species of cyprinids and use two species in Balitoridae as outgroup taxa. Our analyses clarify the phylogenetic position of the paternal and maternal ancestors for the common carp and goldfish. The estimation of matrilineal divergence (10.71-12.42 Ma) is significantly younger than the dates of the parental ancestor divergedthat obtained by nuclear genes (16.62-19.64 Ma). Analyses of both genomes date the allopolyploidization event of the common ancestor of Cy. carpio and Ca sp. to about 10.71-12.42 Ma, which is most likely represented by maternal divergent time. The divergence of the two copies of the nuclear genes which was more ancient than the maternal markers might have been included the divergence of the progenitors' genome divergence when the allopolyploidization event occurred. Thus, the scenarios of allopolyploidzation for this group of fish can be suggested as the following: the matrilineal common ancestor of species in tribe Cyprinini might have doubled its genome by mating with a paternal ancestor in the subfamily Cyprininae, which was a sister-group that diverged around 4.20-8.93 Ma. Our work provides new evidence for the divergence dates of allopolyploidization within the Cyprinini, and documents the necessity of considering both matrilineal and patrilineal histories when investigating allopolyploidization. PMID:25470283

  15. Three new species of Alburnoides (Teleostei: Cyprinidae) from Euphrates River, Eastern Anatolia, Turkey.

    PubMed

    Turan, Davut; Kaya, Cüneyt; Ekmekçi, F Güler; Doğan, Esra

    2014-01-01

    Three new species of Alburnoides, Alburnoides emineae sp. n., Alburnoides velioglui sp. n., Alburnoides recepi sp. n., are described from the Euphrates River drainages (Persian Gulf basin) in eastern Anatolia, Turkey. Alburnoides emineae, from Beyazsu Stream (south-eastern Euphrates River drainage), is distinguished from all species of Alburnoides in Turkey and adjacent regions by a combination of the following characters (none unique to the species): a well developed ventral keel between pelvic and anal fins, commonly scaleless or very rarely 1-2 scales covering the anterior portion of the keel; a deep body (depth at dorsal-fin origin 31-36% SL); 37-43 + 1-2 lateral-line scales, 13½-15½ branched anal-fin rays; number of total vertebrae 41-42, modally 41, comprising 20-21 abdominal and 20-21 caudal vertebrae. Alburnoides velioglui, from Sırlı, Karasu, Divriği and Sultansuyu streams (northern and northeastern Euphrates River drainages), is distinguished by a poorly developed ventral keel, completely scaled; a moderately deep body (depth at dorsal-fin origin 24-29% SL); 45-53 + 1-2 lateral-line scales, 11½ -13½ branched anal-fin rays; number of total vertebrae 41-42, modally 42, comprising 20-22 abdominal and 20-21 caudal vertebrae. Alburnoides recepi, from Merzimen Stream (southern Euphrates River drainage), is distinguished by a well developed ventral keel, completely scaleless; a deep body (depth at dorsal-fin origin 29-34% SL); 47-56 + 2-3 lateral-line scales; 13½-16½ branched anal-fin rays; number of total vertebrae 38-40, comprising 19-21 abdominal and 18-20 caudal vertebrae. PMID:24869683

  16. 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

  17. Complete mitochondrial genome of the amphidromous, red-tailed goby Sicyopterus lagocephalus (Pallas) (Teleostei, Gobiidae).

    PubMed

    Chiang, Tzen-Yuh; Chen, I-Shiung; Lin, Hung-Du; Hsiao, Sheng-Tai; Ju, Yu-Min

    2015-01-01

    In this article, the complete mitogenome of the amphidromous, red-tailed goby, Sicyopterus lagocephalus has been amplified and sequenced by long polymerase chain reaction. This mitochondrial genome consists of 16,500 bp, with 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a non-coding control region (CR), and its gene arrangement is identical to those of most vertebrates. The CR (841 bp) is located between tRNA(Pro) and tRNA(Phe). The overall base composition of the heavy strand is A, 28.9%; G, 16.4%; C, 28.3%; and T, 26.4%, with a slight AT bias of 55.3%. The complete mitogenomic data may provide more informative for phylogenetic approach for gobioid phylogeny especially for Sicydiine gobies. PMID:24102605

  18. The complete mitochondrial genome of a cyprinid fish; Metzia longinasus (Teleostei, Cypriniformes).

    PubMed

    Ma, Qinqin; Luo, Wen

    2016-01-01

    The long polymerase chain reaction and primer walking method were applied for the sequencing of the complete mitochondrial genome sequence of a cyprinid species (Metzia longinasus) collected from the Hongshuihe River of the Pearl River drainage, Guangxi Province in China. It is 16,614 bp in length, containing 2 rRNA, 22 tRNA, 13 protein-coding genes and 1 control region generally found in most vertebrates. Most of the mitochondrial genes are encoded on the heavy strand except for eight tRNA and ND6 genes. The base composition of this genome was 31.9% A, 26.2%C, 26.2%T and 15.7%G, showing a lower level of G (15.7%) and a slighter AT bias (58.1%). This is the 2nd completely sequenced mitogenome from genus Metzia. The mtDNA sequence of M. longinasus shared 93% sequence similarity with that of M. formosae and it could contribute to a better solution of its phylogenetic position within cyprinid fishes based on the complete mitogenomic data. PMID:24491097

  19. The complete mitochondrial genome of Schizothorax prenanti (Tchang) (Teleostei, Cyprinidae, Schizothoracinae).

    PubMed

    Chen, Chun-Na; Huang, Ying-Ying; Li, Hua; Long, Zhi-Hai; Lai, Jian-Sheng; Liu, Guang-Xun; Zhao, Gang

    2016-01-01

    The ya-fish, Schizothorax prenanti, is a well-known commercial cold-water fish species with the hexaploid karyotype distributed in the upper reaches of the Yangtze River and its tributaries on the western Sichuan Plateau in China. The complete mitogenome of S. prenanti is 16,587 bp in length, containing 37 genes of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and a control region (D-loop). The gene nucleotide composition of S. prenanti is 29.6% A, 25.4% T, 27.1% C and 17.9% G, with a slight AT bias of 55.0%. The complete mitogenome sequence of S. prenanti could provide useful data for further studies on genetic structure and diversity, as well as the artificial cultivation and breeding of S. prenanti. PMID:24521499

  20. The complete mitochondrial genome of small sliver gugeon Squalidus gracilis (Teleostei, Cyprinidae).

    PubMed

    Liu, Guo-Di; Chen, I-Shiung; Zhu, Jun-Quan; Shen, Chia-Ning

    2016-01-01

    In this study, the complete mitogenome sequence of small silver gugeon Squalidus gracilis has been amplified. The mitogenome, consisting of 16,605 base pairs (bp), had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes and a non-coding control region (CR). CR of 928 bp length is located between tRNA(Pro) and tRNA(Phe). The overall base composition of S. gracilis is 29.8% for A, 27.6% for C, 25.7% for T and 16.9% for G, with higher AT content of 55.5%. The complete mitogenome may provide rather essential and important DNA molecular data for further phylogenetic analysis for not only congeneric species but also higher different taxa of Cyprinid fishes. PMID:24749978

  1. Glyptothorax igniculus, a new species of sisorid catfish (Teleostei: Siluriformes) from Myanmar.

    PubMed

    Ng, Heok Hee; Kullander, Sven O

    2013-01-01

    Glyptothorax igniculus, new species, is described from the Chindwin River system (part of the Irrawaddy River drainage) in northwestern Myanmar. It differs from other species of Glyptothorax in the Irrawaddy drainage except G. burmanicus in having a thoracic adhesive apparatus with a lanceolate central depression that is nearly enclosed posteriorly by skin ridges, vs. having an adhestive apparatus that is open caudally. In G. burmanicus the adhesive apparatus is oval in outline and completely closed. Glyptothorax chindwinicus Vishwanath & Linthoingambi, 2007 is shown to be a junior synonym of G. burmanicus Prashad & Mukerji, 1929. Glyptothorax rugimentum is reported for the first time from the Chindwin drainage. PMID:25232627

  2. 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. PMID:26739922

  3. 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

    2015-10-01

    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.

  4. 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.

  5. A new Pseudophoxinus (Teleostei, Cyprinidae) species from Asi River Drainage (Turkey)

    PubMed Central

    Küçük, Fahrettin; Güçlü, Salim Serkan

    2014-01-01

    Abstract Pseudophoxinus turani sp. n. is described from the İncesu Spring (Hassa-Hatay) drainage of Asi River, Turkey. It is distinguished from other Eastern Mediterranean Region Pseudophoxinus species by a combination of characters: lateral line incomplete, with 12–25 (commonly 16–21) perforated scales and 38–46+2-3 scales in lateral series (commonly 41–44+2-3); 10–11 scale rows between the lateral line and dorsal-fin origin; 3–4 scale rows between the lateral line and the pelvic–fin origin; dorsal fin with 7½ branched rays; anal fin commonly with 7½ branched rays; 8-11gill rakers on the first branchial arch; dorsal profile markedly convex with marked hump at the nape, ventral profile less convex than dorsal profile; a small, irregular, black blotch on the base of the caudal fin; mouth terminal, with slightly distinct chin, its corner not reaching vertical through anterior margin of eye; snout somewhat long, with rounded tip; and its length greater than eye diameter. PMID:24899855

  6. Complete mitogenomes of King angelfish (Holacanthus passer) and Queen angelfish (Holacanthus ciliaris) (Teleostei: Pomacanthidae).

    PubMed

    Shen, Kang-Ning; Chang, Chih-Wei; 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 King angelfish (Holacanthus passer) and Queen angelfish (Holacanthus ciliaris) for the first time. The assembled mitogenome consists of 16,620 bp in H. passer and 16,606 bp in H. ciliaris, showing 95% identities 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. D-loop contains 903 bp in H. passer and 888 bp in H. ciliaris and locates between tRNA-Pro and tRNA-Phe. The overall GC content is 45.8% for H. passer and 46.2% for H. ciliaris. Complete mitogenomes of King angelfish and Queen angelfish deduced in this study provide essential and important DNA molecular data for further phylogenetic and evolutionary analysis for marine angelfish. PMID:26119118

  7. Complete mitogenomes of Armitage angelfish (Apolemichthys armitagei) and Griffisi angelfish (Apolemichthys griffisi) (Teleostei: Pomacanthidae).

    PubMed

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

    2016-07-01

    In this study, we used the next-generation sequencing method to deduce complete mitogenomes of Armitage angelfish (Apolemichthys armitagei) and Griffisi angelfish (A. griffisi) for the first time. The assembled mitogenomes, consists 16,551 bp (A. armitagei) and 16,528 bp (A. griffisi) in length, shows 92% identity each other. Both mitogenomes follow the typical vertebrate arrangement, including 13 protein coding genes, 22 transfer RNAs, two ribosomal RNAs genes, and a non-coding control region of D-loop. D-loop contains a length of 828 bp in A. armitagei and 849 bp in A. griffisi and locates between tRNA-Pro and tRNA-Phe. Complete mitogenomes of Armitage angelfish and Griffisi angelfish deduced in this study provide essential and important DNA molecular data for further phylogenetic and evolutionary analysis for marine angelfish. PMID:26242720

  8. Complete mitogenomes of Multicolor angelfish (Centropyge multicolor) and Yellowhead angelfish (Centropyge joculator) (Teleostei: Pomacanthidae).

    PubMed

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

    2016-07-01

    Multicolor angelfish (Centropyge multicolor) and Yellowhead angelfish (C. joculator) are in the "multicolor species complex". In this study, we used the next-generation sequencing method to deduce two complete mitogenomes of C. multicolor and C. joculator for the first time. The assembled mitogenome, consisting of 16,791 bp and 16,778 bp, showing 99% identity to each other. Both mitogenome 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. D-loop contains 909 bp in C. multicolor and 896 bp in C. joculator and locates between tRNA-Pro and tRNA-Phe. The overall GC content is 46.9% for C. multicolor and 50.7% for C. joculator. Complete mitogenomes of C. multicolor and C. joculator provide essential and important DNA molecular data for phylogenetic and evolutionary analysis for "multicolor species complex". PMID:26094992

  9. Complete mitogenomes of Spotbreast angelfish (Genicanthus melanospilos) and Blackstriped angelfish (Genicanthus lamarck) (Teleostei: Pomacanthidae).

    PubMed

    Hsiao, Chung-Der; Shen, Kang-Ning; Chan, Yen-Fan; Lin, Zi-Han; Tsai, Shiou-Yi; Chen, Ching-Hung; Chang, Chih-Wei

    2016-07-01

    In this study, we used the next-generation sequencing method to deduce two complete mitogenomes of Spotbreast angelfish (Genicanthus melanospilos) and Blackstriped angelfish (Genicanthus lamarck) for the first time. The assembled mitogenome, consisting of 16 736 bp and 16 616 bp, showing 91.8% identity each other. Both mitogenome 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. D-loop contains 1026 bp in G. melanospilos and 912 bp in G. lamarck and locates between tRNA-Pro and tRNA-Phe. The overall GC content is 46.2% for G. melanospilos and 46.3% for G. lamarck. Complete mitogenomes of G. melanospilos and G. lamarck provide essential and important DNA molecular data for phylogenetic and evolutionary analysis for marine angelfishes. PMID:26153744

  10. Complete mitogenomes of Barred angelfish (Paracentropyge multifasciata) and Purplemask angelfish (Paracentropyge venusta) (Teleostei: Pomacanthidae).

    PubMed

    Shen, Kang-Ning; Chang, Chih-Wei; Tsai, Shiou-Yi; Lin, Zi-Han; Chan, Yen-Fan; 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 Barred angelfish (Paracentropyge multifasciata) and Purplemask angelfish (Paracentropyge venusta) for the first time. The assembled mitogenome, consisting of 16 502 bp and 16 641 bp, showing 88.6% identity each other. Both mitogenome 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. D-loop contains 787 bp in P. multifasciata and 923 bp in P. venusta and locates between tRNA-Pro and tRNA-Phe. The overall GC content is 46.5% for P. multifasciata and 46.2% for P. venusta. Complete mitogenomes of P. multifasciata and P. venusta provide essential and important DNA molecular data for phylogenetic and evolutionary analysis for marine angelfish. PMID:26119124

  11. Complete mitogenomes of Whitetail angelfish (Centropyge flavicauda) and Orangeback angelfish (Centropyge acanthops) (Teleostei: Pomacanthidae).

    PubMed

    Shen, Kang-Ning; Chang, Chih-Wei; Lin, Zi-Han; Chan, Yen-Fan; Tsai, Shiou-Yi; Chen, Ching-Hung; Hsiao, Chung-Der

    2016-07-01

    Whitetail Angelfish (Centropyge flavicauda) and Orangeback Angelfish (Centropyge acanthops) are known as pygmy angelfish due to their small body size (usually less than two inches). In this study, we used the next-generation sequencing method to deduce two complete mitogenomes of C. flavicauda and C. acanthops for the first time. The assembled mitogenome, consisting of 16 747 bp and 16 748 bp, was showing 99.2% identity each other. Both mitogenome follow the typical vertebrate arrangement, including 13 protein coding genes, 22 transfer RNAs, two ribosomal RNAs genes and a non-coding control region of D-loop. D-loop contains 895 bp in C. flavicauda and 896 bp in C. acanthops and locates between tRNA-Pro and tRNA-Phe. The overall GC content is 46.4% for C. flavicauda and C. acanthops. Complete mitogenomes of C. flavicauda and C. acanthops provide essential and important DNA molecular data for phylogenetic and evolutionary analysis for marine angelfish. PMID:26119128

  12. The complete mitogenome of Japanese swallow angelfish (Genicanthus semifasciatus) and Ornate angelfish (Genicanthus bellus) (Teleostei: Pomacanthidae).

    PubMed

    Hsiao, Chung-Der; Shen, Kang-Ning; Tsai, Shiou-Yi; Wu, Shan-Chun; Chen, Ching-Hung; Chang, Chih-Wei

    2016-07-01

    In this study, we used the next-generation sequencing method to determine the complete mitogenome of Japanese swallow angelfish (Genicanthus semifasciatus) and Ornate angelfish (Genicanthus bellus) for the first time. The assembled mitogenome, 16,722 bp and 16,734 bp in length, shows 95% identity to 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. D-loop contains length of 1013 bp in G. semifasciatus and 1030 bp in G. bellus, and is located between tRNA-Pro and tRNA-Phe. The overall GC content is 46.4% for G. semifasciatus and 46.6% for G. bellus. The complete mitogenome of Japanese swallow angelfish and Ornate angelfish determined in this study provides essential and important DNA molecular data for further phylogenetic and evolutionary analyses for marine angelfish. PMID:26024128

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

    PubMed

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

    2014-01-01

    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. PMID:24871515

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

    PubMed

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

    2015-01-01

    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. PMID:26623818

  15. Propiedades físicas del gas en regiones de formación estelar multiples en galaxias BCDs: IIZw33 y Mrk600

    NASA Astrophysics Data System (ADS)

    Campuzano-Castro, F.; Hagele, G.; Cardaci, M.; Bosch, G.; Firpo, V.

    2015-08-01

    In this work we perform a detailed analysis of the spectra of the ionized gas belonging to 9 giant HII regions with violent star formation in two Blue Compact Dwarf galaxies. We have measured a large number of recombination and forbidden lines taking into account the underlying stellar population (defining a pseudo continuum for the hydrogen and helium emission lines). The physical properties of the gas have been estimated using the methodology proposed by our group. For the star forming knots, depending on the data available, we derived: (i) the reddening constant from the hydrogen recombination lines in all the regions, (ii) the electron density in the low excitation zone from the sulphur once ionized [SII]6717 and 6731 emission lines ratio, (iii) the electron temperatures using the auroral lines present in the spectra of several of our regions and applying the direct method or empirical relations and photo ionization models: T([OII]), T([OIII]), T([SII]), T([SIII])], and T([NII]) depending on the quality of the spectra, (iv) ionic abundances of He, O, O, S, S, N, Ne, Ar and Ar in most of the knots, except the last one that could only be measured for one object, (v) the total chemical abundances of O, S, N, Ne and Ar, (vi) the ionization degree from the softness parameter .

  16. La conexión rayos-X -- óptico en la NLR de la galaxia Mrk 573. Mecanismos de ionización.

    NASA Astrophysics Data System (ADS)

    Reynaldi, V.; Guainazzi, M.; Feinstein, C.; Combi, J. A.

    We analyze the ionizing mechanisms for the narrow-line region (NLR) of Mrk 573. The alignment of radio, optical and X-ray features suggest that some interaction may be taking place in this region. We investigate if the optical and X-ray emission are being generated in shock waves triggered by the interaction between the radio jet and the intergalactic medium. FULL TEXT IN SPANISH

  17. Estructura espacial de las órbitas caóticas en un modelo autoconsistente de galaxia elíptica

    NASA Astrophysics Data System (ADS)

    Muzzio, J. C.

    Hemos logrado construir modelos autoconsistentes de sistemas estelares utilizando una aproximación cuadrupolar para el potencial. Esto nos permite determinar órbitas y exponentes de Lyapunov de objetos que tienen posiciones y velocidades equivalentes a las que se obtienen de la funcón de distribución del sistema. La distribución espacial de las órbitas caóticas exhibe considerable estructura y, lo que es más importante aún, los valores de los exponentes de Lyapunov calculados sobre intervalos finitos de tiempo, muestran una fuerte correlación con el comportamiento de la órbita en esos mismos intervalos, por lo que permiten reconocer distintos subsistemas con diferentes distribuciones espaciales.

  18. Balancing genetic uniqueness and genetic variation in determining conservation and translocation strategies: a comprehensive case study of threatened dwarf galaxias, Galaxiella pusilla (Mack) (Pisces: Galaxiidae).

    PubMed

    Coleman, R A; Weeks, A R; Hoffmann, A A

    2013-04-01

    Genetic markers are widely used to define and manage populations of threatened species based on the notion that populations with unique lineages of mtDNA and well-differentiated nuclear marker frequencies should be treated separately. However, a danger of this approach is that genetic uniqueness might be emphasized at the cost of genetic diversity, which is essential for adaptation and is potentially boosted by mixing geographically separate populations. Here, we re-explore the issue of defining management units, focussing on a detailed study of Galaxiella pusilla, a small freshwater fish of national conservation significance in Australia. Using a combination of microsatellite and mitochondrial markers, 51 populations across the species range were surveyed for genetic structure and diversity. We found an inverse relationship between genetic differentiation and genetic diversity, highlighting a long-term risk of deliberate isolation of G. pusilla populations based on protection of unique lineages. Instead, we adopt a method for identifying genetic management units that takes into consideration both uniqueness and genetic variation. This produced a management framework to guide future translocation and re-introduction efforts for G. pusilla, which contrasted to the framework based on a more traditional approach that may overlook important genetic variation in populations. PMID:23432132

  19. Estudio del sistema de cúmulos globulares de la galaxia lenticular NGC6861: en busca de evidencias de una fusión.

    NASA Astrophysics Data System (ADS)

    Escudero, C. G.; Faifer, F. R.; Bassino, L. P.; Calderón, J. P.; Caso, J. P.

    We present a photometric study of the globular cluster system (GCS); associated to the lenticular galaxy NGC6861. It is based on GEMINI/GMOS images in the filters g'; r'; i' of three fields; one of them centered on the galaxy. Studying the colour-magnitude diagram of the system; we detect the presence of at least two populations of GCs (``blue'' and ``red'') and the presence of the phenomenon known as ``blue-tilt''. However; analyzing the colour distribution we infer the existence of a third population with intermediate colours which could be interpreted as evidence of a past interaction or fusion event. FULL TEXT IN SPANISH

  20. Sistema de cúmulos globulares de la galaxia lenticular NGC 6861: en busca de indicios sobre la formación de las S0s.

    NASA Astrophysics Data System (ADS)

    Escudero, C. G.; Faifer, F. R.; Bassino, L. P.; Calderón, J. P.; Caso, J. P.

    We present a preliminar photometric study of the globular cluster system (GCS), associated to the lenticular galaxy (S0) NGC 6861, which is located in a low density environment (d˜31.8 Mpc). It is based on GEMINI/GMOS images (GS-2010B-Q-2: PI Lilia P. Bassino) in the filters g', r', i' of three fields, one of them centered in the galaxy. We find a large number of GCs candidates and detect the presence of at least two sub-populations of GCs (``blue''/metal-poor and ``red''/metal-rich). The spatial distribution of ``red'' candidates presents a higher concentration toward the galaxy (associated to the bulge?), while the distribution of ``blue'' candidates is more homogeneus over the three fields (associated to the halo?). In the color-magnitud diagram, the ``blue'' GC candidates show a possible mass-luminosity relation, known as ``blue-tilt'', probably detected for the first time in a lenticular galaxy. FULL TEXT IN SPANISH

  1. Construcción de un catálogo de cúmulos de galaxias en proceso de colisión

    NASA Astrophysics Data System (ADS)

    de los Ríos, M.; Domínguez, M. J.; Paz, D.

    2015-08-01

    In this work we present first results of the identification of colliding galaxy clusters in galaxy catalogs with redshift measurements (SDSS, 2DF), and introduce the methodology. We calibrated a method by studying the merger trees of clusters in a mock catalog based on a full-blown semi-analytic model of galaxy formation on top of the Millenium cosmological simulation. We also discuss future actions for studding our sample of colliding galaxy clusters, including x-ray observations and mass reconstruction obtained by using weak gravitational lenses.

  2. Synergistic Interactions within Disturbed Habitats between Temperature, Relative Humidity and UVB Radiation on Egg Survival in a Diadromous Fish

    PubMed Central

    Hickford, Michael J. H.; Schiel, David R.

    2011-01-01

    Anthropogenic impacts, including urbanization, deforestation, farming, and livestock grazing have altered riparian margins worldwide. One effect of changes to riparian vegetation is that the ground-level light, temperature, and humidity environment has also been altered. Galaxias maculatus, one of the most widely distributed fishes of the southern hemisphere, lays eggs almost exclusively beneath riparian vegetation in tidally influenced reaches of rivers. We hypothesized that the survival of these eggs is greatly affected by the micro-environment afforded by vegetation, particularly relating to temperature, humidity and UVB radiation. We experimentally reduced riparian vegetation height and altered shading characteristics, tracked egg survival, and used small ground-level temperature, humidity and UVB sensors to relate survival to ground-level effects around egg masses. The ground-level physical environment was markedly different from the surrounding ambient conditions. Tall dense riparian vegetation modified ambient conditions to produce a buffered temperature regime with constant high relative humidity, generally above 90%, and negligible UVB radiation at ground-level. Where vegetation height was reduced, frequent high temperatures, low humidity, and high UVB irradiances reduced egg survival by up to 95%. Temperature effects on egg survival were probably indirect, through reduced humidity, because developing eggs are known to survive in a wide range of temperatures. In this study, it was remarkable how such small variations in relatively small sites could have such a large effect on egg survival. It appears that modifications to riparian vegetation and the associated changes in the physical conditions of egg laying sites are major mechanisms affecting egg survival. The impacts associated with vegetational changes through human-induced disturbances are complex yet potentially devastating. These effects are particularly important because they affect a very small portion of habitat that is required to complete the life history of a species, despite the wide distribution of adults and juveniles across aquatic and marine environments. PMID:21931680

  3. The impacts of stress on sodium metabolism and copper accumulation in a freshwater fish.

    PubMed

    Harley, Rachel A; Glover, Chris N

    2014-02-01

    In freshwater fish, stress can often result in significant modifications to Na(+) metabolism and may be an important aspect to consider in conservation efforts; as maintaining ion balance is critical to survival and ion transport is also a key determinant of metal toxicity. In order to better quantify the response of stress, Na(+) influx, Na(+) efflux, and copper accumulation were measured as a result of handling stress in inanga (Galaxias maculatus). This species is a culturally and economically important fish in New Zealand as one of the major species in the local 'whitebait' fishery. Na(+) influx rates in inanga were found to be 2-3 times greater after handling than in 'recovered' fish, and Na(+) efflux rates increased in the range of 5-6 times. Both influx and efflux rates quickly returned to resting levels within 24h. Increases in Na(+) efflux were strongly correlated with opercular beat frequency. This suggests an increas in ventilation, and subsequent enhanced diffusive loss of Na(+), as the mechanism of increased Na(+) efflux. Total body copper levels were also measured under similar treatments. Fish had significantly higher levels of copper directly after handling than following a 24h recovery; likely due to a shared Na(+)/copper uptake pathway. As accumulation is linked to toxicity, fish exposed to elevated copper levels in stressful environments will consequently be more at risk to metal toxicity. In a natural environment, stress can come from many different sources; among which, anthropogenic disturbances can often be a cause. Given that inanga must migrate through metal-contaminated coastal regions to reach breeding habitats, they will be exposed to toxicants under conditions where perfusion and ventilation of the gill is increased. As such, ion loss would be exacerbated, leading to an enhanced compensatory ion uptake and an increase in accumulation of ion-mimicking toxicants such as copper, exacerbating toxicity. This is a concern as conservation efforts in more disruptive environments may not be adequately protected. PMID:24374847

  4. Synergistic interactions within disturbed habitats between temperature, relative humidity and UVB radiation on egg survival in a diadromous fish.

    PubMed

    Hickford, Michael J H; Schiel, David R

    2011-01-01

    Anthropogenic impacts, including urbanization, deforestation, farming, and livestock grazing have altered riparian margins worldwide. One effect of changes to riparian vegetation is that the ground-level light, temperature, and humidity environment has also been altered. Galaxias maculatus, one of the most widely distributed fishes of the southern hemisphere, lays eggs almost exclusively beneath riparian vegetation in tidally influenced reaches of rivers. We hypothesized that the survival of these eggs is greatly affected by the micro-environment afforded by vegetation, particularly relating to temperature, humidity and UVB radiation. We experimentally reduced riparian vegetation height and altered shading characteristics, tracked egg survival, and used small ground-level temperature, humidity and UVB sensors to relate survival to ground-level effects around egg masses. The ground-level physical environment was markedly different from the surrounding ambient conditions. Tall dense riparian vegetation modified ambient conditions to produce a buffered temperature regime with constant high relative humidity, generally above 90%, and negligible UVB radiation at ground-level. Where vegetation height was reduced, frequent high temperatures, low humidity, and high UVB irradiances reduced egg survival by up to 95%. Temperature effects on egg survival were probably indirect, through reduced humidity, because developing eggs are known to survive in a wide range of temperatures. In this study, it was remarkable how such small variations in relatively small sites could have such a large effect on egg survival. It appears that modifications to riparian vegetation and the associated changes in the physical conditions of egg laying sites are major mechanisms affecting egg survival. The impacts associated with vegetational changes through human-induced disturbances are complex yet potentially devastating. These effects are particularly important because they affect a very small portion of habitat that is required to complete the life history of a species, despite the wide distribution of adults and juveniles across aquatic and marine environments. PMID:21931680

  5. Separating natural responses from experimental artefacts: habitat selection by a diadromous fish species using odours from conspecifics and natural stream water.

    PubMed

    Hale, Robin; Swearer, Stephen E; Downes, Barbara J

    2009-03-01

    Animals use sensory stimuli to assess and select habitats, mates and food as well as to communicate with other individuals. One way they do this is to use olfaction, whereby they identify and respond to chemical cues. All organisms release odours, which mix with other chemical substances and ambient environmental conditions. The result is that animals are frequently immersed in a complex, highly dynamic sensory environment where they must identify and respond to only some of the potential stimuli they encounter in the face of significant levels of background noise. Understanding how organisms respond to different chemical cues is therefore dependent on knowing how these responses might be influenced by potential interactions with other stimuli. To test this, we examined whether the diadromous fish Galaxias maculatus was attracted to conspecific odours and whether this response differed when cues were offered in an artificial environment lacking other potential chemical stimuli (tap water) or a more natural background environment (stream water). We found that (1) fish responded to both natural stream water odours and those from conspecifics but the response to the latter was stronger; (2) the attraction to conspecific odours was stronger in tap water than in stream water, which indicates the importance of these odours may be overestimated when they are offered in artificial media. We also conducted a brief literature review, which confirmed that artificial media are commonly used in experiments and that the background environment is often not considered. Our results show that future research testing the responses of organisms to auditory, olfactory and visual cues should carefully consider the context in which cues are presented. Without doing so, such studies may inaccurately assess the importance of sensory cues in natural situations in the wild. PMID:19139923

  6. Mercury in the biotic compartments of Northwest Patagonia lakes, Argentina.

    PubMed

    Rizzo, A; Arcagni, M; Arribére, M A; Bubach, D; Guevara, S Ribeiro

    2011-06-01

    We report on total mercury (THg) concentrations in the principal components of food webs of selected Northern Patagonia Andean Range ultraoligotrophic lakes, Argentina. The THg contents were determined using Instrumental Neutron Activation Analysis in muscle and liver of four fish species occupying the higher trophic positions (the introduced Salmo trutta, Oncorhynchus mykiss and Salvelinus fontinalis, and the native Percichthys trucha) accounted for eight lakes belonging to Nahuel Huapi and Los Alerces National Parks. We studied the food web components of both the West and East branches of Lake Moreno, including benthic primary producers such as biofilm, mosses, and macrophytes, three plankton fractions, fish, riparian tree leaves, and benthic invertebrates, namely decapods, molluscs, insect larvae, leeches, oligochaetes, and amphipods. Mercury concentrations in fish muscle varied in a wide range, from less than 0.05 to 4 μg g(-1) dry weight (DW), without a distribution pattern among species but showing higher values for P. trucha and S. fontinalis, particularly in Lake Moreno. The THg contents of the food web components of Lake Moreno varied within 4 orders of magnitude, with the lower values ranging from 0.01 to 0.5 μg g(-1) DW in tree leaves, some macrophytes, juvenile salmonids or benthic macroinvertebrates, and reaching concentrations over 200 μg g(-1) DW in the plankton. Juvenile Galaxias maculatus caught in the pelagic area presented the highest THg contents of all fish sampled, reaching 10 μg g(-1) DW, contents that could be associated with the high THg concentrations in plankton since it is their main food source. Although Lake Moreno is a system without local point sources of contamination, situated in a protected area, some benthic organisms presented high THg contents when compared with those from polluted ecosystems. PMID:21421254

  7. Population sinks resulting from degraded habitats of an obligate life-history pathway.

    PubMed

    Hickford, Michael J H; Schiel, David R

    2011-05-01

    Many species traverse multiple habitats across ecosystems to complete their life histories. Degradation of critical, life stage-specific habitats can therefore lead to population bottlenecks and demographic deficits in sub-populations. The riparian zone of waterways is one of the most impacted areas of the coastal zone because of urbanisation, deforestation, farming and livestock grazing. We hypothesised that sink populations can result from alterations of habitats critical to the early life stages of diadromous fish that use this zone, and tested this with field-based sampling and experiments. We found that for Galaxias maculatus, one of the most widely distributed fishes of the southern hemisphere, obligate riparian spawning habitat was very limited and highly vulnerable to disturbance across 14 rivers in New Zealand. Eggs were laid only during spring tides, in the highest tidally influenced vegetation of waterways. Egg survival increased to >90% when laid in three riparian plant species and where stem densities were great enough to prevent desiccation, compared to no survival where vegetation was comprised of other species or was less dense. Experimental exclusion of livestock, one of the major sources of riparian degradation in rural waterways, resulted in quick regeneration, a tenfold increase in egg laying by fish and a threefold increase in survival, compared to adjacent controls. Overall, there was an inverse relationship between river size and egg production. Some of the largest rivers had little or no spawning habitat and very little egg production, effectively becoming sink populations despite supporting large adult populations, whereas some of the smallest pristine streams produced millions of eggs. We demonstrate that even a wide-ranging species with many robust adult populations can be compromised if a stage-specific habitat required to complete a life history is degraded by localised or more diffuse impacts. PMID:21076966

  8. Modeling prey consumption by native and non-native piscivorous fishes: implications for competition and impacts on shared prey in an ultraoligotrophic lake in Patagonia

    USGS Publications Warehouse

    Juncos, Romina; Beauchamp, David A.; Viglianoc, Pablo H.

    2013-01-01

    We examined trophic interactions of the nonnative salmonids Rainbow Trout Oncorhynchus mykiss, Brown Trout Salmo trutta, and Brook Trout Salvelinus fontinalisand the main native predator Creole Perch Percichthys trucha in Lake Nahuel Huapi (Patagonia, Argentina) to determine the relative impact of each predator on their forage base and to evaluate the potential vulnerability of each predator to competitive impacts by the others. Using bioenergetics simulations, we demonstrated the overall importance of galaxiids and decapods to the energy budgets of nonnative salmonids and Creole Perch. Introduced salmonids, especially Rainbow Trout, exerted considerably heavier predatory demands on shared resources than did the native Creole Perch on both a per capita basis and in terms of relative population impacts. Rainbow Trout consumed higher quantities and a wider size range of Small Puyen (also known as Inanga) Galaxias maculatus than the other predators, including early pelagic life stages of that prey; as such, this represents an additional source of mortality for the vulnerable early life stages of Small Puyen before and during their transition from pelagic to benthic habitats. All predators were generally feeding at high feeding rates (above 40% of their maximum physiological rates), suggesting that competition for prey does not currently limit either Creole Perch or the salmonids in this lake. This study highlights the importance of keystone prey for the coexistence of native species with nonnative top predators. It provides new quantitative and qualitative evidence of the high predation pressure exerted on Small Puyen, the keystone prey species, during the larval to juvenile transition from pelagic to littoral-benthic habitat in Patagonian lakes. This study also emphasizes the importance of monitoring salmonid and Creole Perch population dynamics in order to detect signs of potential impacts through competition and shows the need to carefully consider the rationale behind any additional trout stocking.

  9. Species profiles: Life history and environmental requirements of coastal fishes and invertebrates (South Florida): King mackerel and Spanish mackerel. [Scomberomorus cavalla; Scomberomorus maculatus

    SciTech Connect

    Godcharles, M.F.; Murphy, M.D.

    1986-06-01

    This Species Profile on king and Spanish mackerel summarizes the taxonomy, morphology, distribution, life history, fishery descriptions, ecological role, and environmental requirements of these coastal pelagic fish to assist environmental impact assessment. King and Spanish mackerel support major commercial and sport fisheries in south Florida. In 1974 to 1983, Gulf of Mexico and Atlantic commercial landings of king mackerel declined from 10.4 to 4.3 million lb.; Spanish mackerel have fluctuated between 4.9 to 17.4 million lb. Both inhabit coastal waters, but Spanish mackerel are generally found closer to beaches and in outer estuarine waters. Both species feed principally on estuarine-dependent species. They are highly migratory, exhibiting seasonal migrations to winter feeding grounds off south Florida and summer spawning/feeding grounds in the northern Gulf of Mexico and off the Atlantic coast of the Southeastern US. Spawning occurs from March/April through September/October between the middle and Outer Continental Shelf (35 to 183 mi) for king mackerel and the inner shelf (12 to 34 mi) for Spanish mackerel. King mackerel reach sexual maturity in their 3rd and 4th years and Spanish, between their 2nd and 3rd. Female king mackerel live longer and grow larger and faster than males. Spanish mackerel live to 8 years; females also grow faster than males. King and Spanish mackerel feed principally on schooling fishes. Larvae and juveniles of both species are prey to little tunny and dolphin; adults are prey for sharks and bottlenose dolphin. Temperature and salinity are important factors regulating mackerel distribution.

  10. Longitudinal monitoring of plasma and fecal androgens in the Tasmanian devil (Sarcophilus harrisii) and the spotted-tailed quoll (Dasyurus maculatus).

    PubMed

    Hesterman, H; Jones, S M

    2009-06-01

    Improved knowledge of the breeding biology of carnivorous marsupials is warranted given their heightened conservation status. Past studies have focused on smaller dasyurids and little is known of male reproductive physiology in the larger species. This study aimed to characterize the pattern of androgen concentrations in male devils and spotted-tailed quolls and to evaluate fecal steroid measurement as a practical, alternative technique for monitoring reproductive activity. Blood and fecal samples were collected from captive adult devils (n=6) and adult quolls (n=8). Plasma and fecal androgen concentrations were significantly positively correlated. In both species there was a significant effect of season on androgen concentrations; and the annual increase preceded female estrus activity. For devils, fecal androgens were elevated during the austral summer: peak concentrations were observed in January-February, and copulation occurred from late February-late May. In quolls, fecal androgen concentrations were highest during austral autumn/winter: the annual increase began in April and copulation occurred from mid-May to early October. The lengthy period of elevated plasma and fecal androgens and protracted annual period of mating activity implies a period of extended spermatogenesis in both species. PMID:18602773

  11. 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.

  12. Molecular phylogeny of Percomorpha resolves Trichonotus as the sister lineage to Gobioidei (Teleostei: Gobiiformes) and confirms the polyphyly of Trachinoidei.

    PubMed

    Thacker, Christine E; Satoh, Takashi P; Katayama, Eri; Harrington, Richard C; Eytan, Ron I; Near, Thomas J

    2015-12-01

    The percomorph fish clade Gobiiformes is a worldwide, tropical and temperate radiation with species occupying nearly all aquatic, and some semi-terrestrial, habitats. Early molecular phylogenetic studies led to the discovery of Gobiiformes, which contains Gobioidei, the gobies and sleepers, and a clade (Apogonoidei) consisting of Apogonidae and Kurtus, the cardinalfishes and nurseryfishes. Gobioidei is consistently resolved as monophyletic in molecular studies, and includes eight families whose members range from waterfall climbing stream gobies to several prominent lineages inhabiting coral reefs. The sister taxon to Gobioidei is also reliably resolved as Apogonoidei. Despite the consistent support for gobiiform monophyly in molecular studies, it is not known if percomorph lineages unsampled in molecular phylogenetic studies are closely related to Gobioidei or Apogonoidei. Here we assemble a large dataset of DNA sequence from ten protein-coding genes, sampling widely across Acanthomorpha and Percomorpha, including Gobioidei, Apogonidae, and Kurtus, along with representatives of all twelve families comprising the former Trachinoidei. The phylogenies inferred from the nuclear gene sequences show that Trachinoidei is polyphyletic, with constituent lineages spread widely among several major percomorph clades. Most notably, the sanddivers (Trichonotus) are resolved as the sister lineage of Gobioidei. This study clarifies the phylogenetic relationships of lineages previously classified in Trachinoidei, identifies Trichonotus as the sister lineage of gobies, provides a molecular phylogeny of the major lineages of Gobioidei, and offers suggested changes to percomorph classification. PMID:26265255

  13. Myxobolus myleus n. sp. infecting the bile of the Amazonian freshwater fish Myleus rubripinnis (Teleostei: Serrasalmidae): morphology and pathology.

    PubMed

    Azevedo, Carlos; São Clemente, Sérgio Carmona; Casal, Graça; Matos, Patrícia; Alves, Ângela; Al-Quraishy, Saleh; Matos, Edilson

    2012-07-01

    Myxobolus myleus n. sp. is described from the gall-bladder of the freshwater fish Myleus rubripinnis collected near the city of Oriximiná in the Amazon System, Brazil. The spores obtained from the bile contained two equal symmetrical and smooth valves, each forming the spore wall. The spores were large, with a cone-like form, a semi spherical basal contour and measured (in μm) 19.3 ± 0.5 (n = 25) × 8.3 ± 0.5 (n = 25) × 4.0 ± 0.3 (n = 15). The apical end of the spores contained two elongate, equal and pointed conical polar capsules measuring 13.2 ± 0.4 μm (n = 25) in length and 3.0 ± 0.3 μm (n = 15) in width, each having a slightly tapering polar filament with 19 to 21 turns. The polar capsules were extended below at about 4/5 of the total length of the spores. The sporoplasm was binucleate and contained some sporoplasmosomes. All infected fish presented hypertrophy of the gall-bladder due to presence of the brownish parasite floating in the bile. In this paper we describe this new species of myxosporean based on light and ultrastructural observations, together with its associated pathology. PMID:22711511

  14. Composition and structure of the parasite faunas of cod, Gadus morhua L. (Teleostei: Gadidae), in the North East Atlantic

    PubMed Central

    Perdiguero-Alonso, Diana; Montero, Francisco E; Raga, Juan Antonio; Kostadinova, Aneta

    2008-01-01

    Background Although numerous studies on parasites of the Atlantic cod, Gadus morhua L. have been conducted in the North Atlantic, comparative analyses on local cod parasite faunas are virtually lacking. The present study is based on examination of large samples of cod from six geographical areas of the North East Atlantic which yielded abundant baseline data on parasite distribution and abundance. Materials and Methods A total of 826 fish was sampled in the Baltic, Celtic, Irish and North seas, Icelandic waters and Trondheimsfjord (Norway) in 2002 (spring and autumn) and 2003 (spring). The gills and internal organs (oesophagus, stomach, intestine, pyloric caeca, liver, heart, spleen, gall bladder and gonads) were examined for macroparasites following a standardised protocol. The taxonomic consistency of the identification was ensured thorough the entire study. Results We discuss some problems in parasite identification, outline the composition of the parasite faunas in cod in the six North East Atlantic regions, provide novel data on parasite prevalence and abundance and a comparative assessment of the structure of the regional parasite faunas with respect to the higher-level taxonomic groupings, host specificity and zoogeographical distribution of the parasites. Altogether 57 different parasite forms were found including seven new host records (Diclidophora merlangi, Rhipidocotyle sp., Fellodistomum sp., Steringotrema sp., Cucullanus sp., Spinitectus sp., and Chondracanthus ornatus). The predominant groups of cod parasites were trematodes (19 species) and nematodes (13 species) including larval anisakids which comprised 58.2% of the total number of individuals. Conclusion Our study reveals relatively rich regional parasite faunas in cod from the North East Atlantic which are dominated by generalist parasites with Arcto-Boreal distribution. Further, it provides more detailed data on the distribution in the North East Atlantic of the majority of cod parasites which may serve as baselines for future studies on the effect of climate change. Based on the faunal comparisons, predictions can be made in relation to the structure and diversity of the parasite communities in the North East Atlantic regions studied. PMID:18638387

  15. 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.

  16. Embryonic and larval developmental stages of African giant catfish Heterobranchus bidorsalis (Geoffroy Saint Hilaire, 1809) (Teleostei, Clariidae).

    PubMed

    Olaniyi, Wasiu Adekunle; Omitogun, Ofelia Galman

    2014-01-01

    The dearth of African giant catfish Heterobranchus bidorsalis seeds poses great threat to its aquaculture and biodiversity, hence detailed knowledge and understanding of its embryology is indispensable for its artificial propagation and conservation programmes. Photomicrographs of extruded oocyte through all developmental cell stages of live embryo to larval stage are documented with the aid of a light microscope. The optical transparency of the developing embryo enabled us to describe its deep structures, distinctive features and characterize the stages pictorially. Extruded oocyte had a mean diameter of 1 ± 0.1 mm, ~20% increase when hydrated, and bounded by double thin perivitelline membranes. The first mitotic cleavage occurred at 69 min post-fertilization (pf) resulting in 2, 4 (2 × 2 array of cells), 8 (2 × 4), 16 (4 × 4), 32 (4 × 8), 64 (2 × 4 × 8) blastomeres, then developed to morula, blastula and gastrula stages. Blastula was featured by formation of enveloping layer and yolk syncytial layer. Onset of epiboly at 3 h 57 min depicted the commencement of gastrula while closure of blastopore at 11 h 8 min marked its completion. Neurulation period was distinct from segmentation where organogenesis was fully active. Embryo sudden muscular contraction was noticed at ~17 h pf, increased prior to hatching with caudal locomotion firstly at 42 s interval. Heartbeat of embryo commenced at ~1 h before its unique eclosion at average of 72 beats/min while first larva emerged at 21 h at a controlled temperature of 28.5 ± 0.5°C. Mean total length (TL) of larvae and their pouch thickness were 5 ± 1 mm and 0.05 ± 0.02 mm respectively. 1 -day old larvae revealed 8 distinctive neuromeres and by day 3, epicanthus folds of the eyes were fully uncovered; and thereafter commenced exogenous feeding. At day 4, larvae recorded mean TL of 9 ± 1 mm and 15 caudal fin rays. The fin bifurcation to dorsal and adipose fins was observed at third and half weeks post-hatchability with the dorsal fin length to adipose fin was 1.7:1. This study, for the first time, presents significant morpho-sequential developmental stages of H. bidorsalis and registers its unique form of eclosion. PMID:25512884

  17. 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. PMID:25462998

  18. The occurrence of serological H-Y antigen (Sxs antigen) in the diandric protogynous wrasse, Coris julis (L.) (Labridae, Teleostei).

    PubMed

    Reinboth, R; Mayerová, A; Ebensperger, C; Wolf, U

    1987-01-01

    The serological sex-specific (Sxs) antigen (previously called 'H-Y antigen') has been shown, in various vertebrate species ranging from fish to mammals, to be characteristic of the heterogametic sex. We studied a protogynous hermaphrodite, Coris julis, in order to examine whether the change of a female to a secondary male also involves a change in the Sxs-antigen phenotype. The (homogametic) females of this species were found to be Sxs negative, while both primary and secondary males were Sxs positive. This was true not only for gonads but also for nongonadal tissues. The administration of androgen to females is known to cause sex inversion in this species; we were able to demonstrate this again at the histological level, and found that androgen results in a Sxs positive phenotype in all tissues studied (gonads, spleen, muscle). We propose that androgen is responsible, directly or indirectly, for the occurrence of the Sxs antigen. PMID:3609529

  19. Some aspects of the biology and ecology of Knipowitschia caucasica (Teleostei: Gobiidae) in the Evros Delta (North Aegean Sea)

    NASA Astrophysics Data System (ADS)

    Kevrekidis, T.; Kokkinakis, A. K.; Koukouras, A.

    1990-06-01

    Some aspects of the biology and ecology of the goby Knipowitschia caucasica were studied over a period of 13 months in a poly-to euhaline area in the Evros Delta (North Aegean Sea). This fish grows rapidly in the summer and autumn after hatching, matures after its first winter, breeds from the end of April to the end of July, and grows rapidly again in July September. The older males perish after their second February, whereas some females have a second breeding season at the end of April/beginning of May, shortly before their death. The fish grows to about 40 mm in total length. There is a positive correlation between the total length (TL) and the standard length (SL) or the cleaned body weight (CW). SL increases slower than TL, whereas CW increases slower than TL in immature individuals and faster in males and females. There is no difference between immature individuals, males and females, in the growth rate of SL, TL and CW, TL. The mean monthly values of the condition factor varies from 0.289 to 0.576 in females and from 0.313 to 0.548 in males. The overall sex ratio of females to males is 1: 1.46. Fecundity ranges from 60 to 217 eggs with a mean value of 109.8 and depends upon size, whereas relative fecundity varies between 968 and 2170 with a mean of 1558. The fish feeds predominantly on benthic amphipods and polychaetes.

  20. First evidence for interspecific hybridization between invasive goby species Neogobius fluviatilis and Neogobius melanostomus (Teleostei: Gobiidae: Benthophilinae).

    PubMed

    Lindner, K; Cerwenka, A F; Brandner, J; Gertzen, S; Borcherding, J; Geist, J; Schliewen, U K

    2013-06-01

    Two hybrids between the monkey goby Neogobius fluviatilis and the round goby Neogobius melanostomus from the Rhine River were identified by genotyping and morphological comparison. These are the first records of goby-hybrids outside the parent species' native ranges worldwide. PMID:23731157

  1. Callogobius liolepis Bleeker, a senior synonym of Gobiopsis aporia Lachner and McKinney (Teleostei: Gobiidae: Gobiopsis).

    PubMed

    Delventhal, Naomi R; Mooi, Randall D

    2014-01-01

    Callogobius liolepis Bleeker in Koumans was briefly described from two specimens from Ambon. A later, more detailed description by Koumans was apparently based on Bleeker's unpublished description and specimens of C. okinawae (Snyder), considerably complicating the taxonomy of several species. Re-examination of the syntypes identifies C. liolepis as a species of the genus Gobiopsis Steindachner due to the absence of raised vertical ridges of papillae that characterise Callogobius and the presence of barbels in a pattern unique among gobiids to a subset of Gobiopsis. Gobiopsis liolepis (Bleeker) is determined as the senior synonym of G. aporia Lachner and McKinney based on the absence of head pores combined with the presence of a series of tightly spaced papillae over the eye, lateral scale counts of 36-42, pectoral-fin ray counts of 20-21, dorsal-fin ray counts VI+I,10 and anal-fin ray counts of I,9. The larger syntype is designated the lectotype and the smaller the paralectotype. Specimens identified as C. liolepis in museums or the literature are likely referable to C. okinawae (Snyder) or C. bifasciatus (Smith). PMID:24870626

  2. Chriolepis bilix, a new species of goby (Teleostei: Gobiidae) from deep waters of the western Atlantic.

    PubMed

    Hastings, Philip A; Findley, Lloyd T

    2013-01-01

    A new species of seven-spined goby of the genus Chriolepis is described from four specimens from four widely separate western Atlantic localities (Little Bahama Bank; off southwestern Florida; Tobago Island; and northeastern Colombia) from depths ranging from 62 to 138 m. The species is distinct from all other western Atlantic species currently assigned to the genus Chriolepis in having a fully scaled body, the first two dorsal-fin spines greatly elongated in both sexes, especially so in females, and two anal-fin pterygiophores inserted anterior to the first haemal spine. It differs from members of the similar genus Varicus in having branched pelvic-fins rays, a longer fifth pelvic-fin ray and more numerous meristic elements. It closely resembles Chriolepis atrimelum, known from a similar depth at Isla del Coco in the eastern Pacific Ocean.  PMID:25113374

  3. 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

    2015-01-01

    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. PMID:26250196

  4. Brain-derived neurotrophic factor (BDNF)-like immunoreactivity localization in the retina and brain of Cichlasoma dimerus (Teleostei, Perciformes).

    PubMed

    Vissio, P G; Cánepa, M M; Maggese, M C

    2008-08-01

    Brain-derived neurotrophic factor (BDNF) is a neurotrophin involved in the development and maintenance of vertebrate nervous systems. Although there were several studies in classical animal models, scarce information for fish was available. The main purpose of this study was to analyze the distribution of BDNF in the brain and retina of the cichlid fish Cichlasoma dimerus. By immunohistochemistry we detected BDNF-like immunoreactive cells in the cytoplasm and the nuclei of the ganglion cell layer and the inner nuclear layer of the retina. In the optic tectum, BDNF-like immunoreactivity was detected in the nucleus of neurons of the stratum periventriculare and the stratum marginale and in neurons of the intermediate layers. In the hypothalamus we found BDNF-like immunoreactivity mainly in the cytoplasm of the nucleus lateralis tuberis and the nucleus of the lateral recess. To confirm the nuclear and cytoplasm localization of BDNF we performed subcellular fractionation, followed by Western blot, detecting a 39 kDa immunoreactive-band corresponding to a possible precursor form of BDNF in both fractions. BDNF-like immunoreactivity was distributed in areas related with photoreception (retina), the integration center of retinal projections (optic tectum) and the control center of background and stress adaptation (hypothalamus). These results provide baseline anatomical information for future research about the role of neurotrophins in the adult fish central nervous system. PMID:18343472

  5. Early development of the pineal photoreceptors prior to the retinal differentiation in the embryonic rainbow trout, Oncorhynchus mykiss (Teleostei).

    PubMed

    Omura, Y; Oguri, M

    1993-08-01

    The development of the pineal and retinal photoreceptors in the embryonic rainbow trout, Oncorhynchus mykiss was investigated by means of light and electron microscopy. The pineal photoreceptors endowed with photoreceptive outer segments and signal-transmitting synapses appeared first 15 days after fertilization, and well developed by 21 days. In contrast, the retinal photoreceptors appeared as late as 27 days after fertilization (1 day before hatching). This temporal disparity in photoreceptor development has been compared with the photoperiodic formation of otolith increments, which is initiated during an early developmental stage lacking retinal photoreception. It has been suggested that the early development of pineal photoreceptors may be involved in light-dark recognition, establishment of the diel and circadian rhythms, and entrainment to the environmental photoperiod in the embryonic rainbow trout. PMID:8240856

  6. Evolutionary and biogeographic patterns of the Badidae (Teleostei: Perciformes) inferred from mitochondrial and nuclear DNA sequence data.

    PubMed

    Rüber, Lukas; Britz, Ralf; Kullander, Sven O; Zardoya, Rafael

    2004-09-01

    We reconstructed phylogenetic relationships of the family Badidae using both mitochondrial and nuclear nucleotide sequence data to address badid systematics and to evaluate the role of vicariant speciation on their evolution and current distribution. Phy-logenetic hypotheses were derived from complete cytochrome b (1,140 base pairs) sequences of 33 individuals representing 13 badid species, and using three species of Nandidae as outgroups. Additionally, we sequenced the nuclear RAG1 (1,473 base pairs) and Tmo-4C4 (511 base pairs) genes from each of the badid species and one representative of the outgroup. Our molecular data provide the first phylogenetic hypothesis of badid intrarelationships. Analysis of the mitochondrial and nuclear nucleotide sequence data sets resulted in well-supported trees, indicating a basal split between the genera Dario and Badis, and further supporting the division of the genus Badis into five species groups as suggested by a previous taxonomic revision of the Badidae. Within the genus Badis, mitochondrial and nuclear phylogenies differed in the relative position of B. kyar. We also used our molecular phylogeny to test a vicariant speciation hypothesis derived from geological evidence of large-scale changes in drainage patterns in the Miocene affecting the Irrawaddy- and Tsangpo-Brahmaputra drainages, in the southeastern Himalaya. Within both genera, Badis and Dario, we observed a divergence into Irrawaddy- and Tsangpo-Brahmaputra clades. Using a cytb substitution rate of 8.2 x 10(-9) (substitutions x base pair(-1) x year(-1), we tentatively date this vicariant event at the Oligocene-Miocene boundary (19-24Myr). It is concordant with a hypothesized paleo connection of the Tsangpo river with the Irrawaddy drainage that was most likely interrupted during Miocene orogenic events through tectonic uplifts in eastern Tibet. Our data, therefore, indicate a substantial role of vicariant-based speciation shaping the current distribution patterns of badids. PMID:15354300

  7. 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

  8. Development of the splanchnocranium in Prochilodus argenteus (Teleostei: Characiformes) with a discussion of the basal developmental patterns in the Otophysi.

    PubMed

    Carvalho, Murilo; Vari, Richard P

    2015-02-01

    Development of the mandibular, hyoid and gill arches, which constitute the splanchnocranium, are described for Prochilodus argenteus, order Characiformes, one of the basal lineages of the Otophysi. Development was examined from just hatched larvae through juveniles using whole specimens cleared and counterstained for cartilage and bone as well as histological preparations. Observations are compared with the developmental trends reported for Cypriniformes, the basalmost clade of the Otophysi. Shortened developmental sequences for Prochilodus compared to the cypriniform Catostomus were discovered in the ontogeny of the ceratohyals, ceratobranchials 1-5, epibranchials 1-4 and the symplectic portion of the hyosymplectic. Prochilodus also differs from Catostomus in having the basihyal plus the anterior copula appearing at different stages of ontogeny rather than simultaneously. Contrary to previous assumptions, developmental information indicates that hypobranchial 4 as well as likely basibranchial 5 are present in Prochilodus. Various developmental patterns in Prochilodus considered basal for the Otophysi, the predominant component of the Ostariophysi, are likely conserved from patterns prevalent in basal groups in the Actinopterygii. PMID:25595854

  9. 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. PMID:23178741

  10. Three sympatric karyomorphs in the fish Astyanax fasciatus (Teleostei, Characidae) do not seem to hybridize in natural populations

    PubMed Central

    Ferreira-Neto, Maressa; Artoni, Roberto Ferreira; Vicari, Marcelo Ricardo; Moreira-Filho, Orlando; Camacho, Juan Pedro Martínez; Bakkali, Mohammed; de Oliveira, Claudio; Foresti, Fausto

    2012-01-01

    Abstract Ninety individuals of the characid fish Astyanax fasciatus (Cuvier, 1819) were collected at Água da Madalena stream (Botucatu, São Paulo, Brazil) and analyzed for diploid chromosome number 2n and karyotype composition as well as for the chromosomal location of the 5S and 18S ribosomal DNA (rDNA). Whereas no chromosome differences were associated with sex, three different karyomorphs with diploid chromosome numbers 2n=46, 2n=48 and 2n=50 were found. No intermediate 2n numbers were discovered. The 2n=50 karyomorph showed some differences in 18S rDNA location compared to the two other karyomorphs. Finally, all specimens with the 2n=46 karyomorph showed the presence of a partly heterochromatic macro supernumerary chromosome, which was absent in all individuals with the two other karyomorphs. All these results suggest that indviduals of the three different karyomorphs are not likely to hybridize in the examined populations. Our findings strongly suggest the presence of three separate species (sensu biological species concept) easily diagnosed on the basis of differences in the diploid chromosome numbers and other chromosomal markers. PMID:24260650

  11. Three sympatric karyomorphs in the fish Astyanax fasciatus (Teleostei, Characidae) do not seem to hybridize in natural populations.

    PubMed

    Ferreira-Neto, Maressa; Artoni, Roberto Ferreira; Vicari, Marcelo Ricardo; Moreira-Filho, Orlando; Camacho, Juan Pedro Martínez; Bakkali, Mohammed; de Oliveira, Claudio; Foresti, Fausto

    2012-01-01

    Ninety individuals of the characid fish Astyanax fasciatus (Cuvier, 1819) were collected at Água da Madalena stream (Botucatu, São Paulo, Brazil) and analyzed for diploid chromosome number 2n and karyotype composition as well as for the chromosomal location of the 5S and 18S ribosomal DNA (rDNA). Whereas no chromosome differences were associated with sex, three different karyomorphs with diploid chromosome numbers 2n=46, 2n=48 and 2n=50 were found. No intermediate 2n numbers were discovered. The 2n=50 karyomorph showed some differences in 18S rDNA location compared to the two other karyomorphs. Finally, all specimens with the 2n=46 karyomorph showed the presence of a partly heterochromatic macro supernumerary chromosome, which was absent in all individuals with the two other karyomorphs. All these results suggest that indviduals of the three different karyomorphs are not likely to hybridize in the examined populations. Our findings strongly suggest the presence of three separate species (sensu biological species concept) easily diagnosed on the basis of differences in the diploid chromosome numbers and other chromosomal markers. PMID:24260650

  12. [Effect of different acclimatization temperatures on the ultrastructure of neuronal synapses of perch (Tilapia mariae; Cichlidae, Teleostei)].

    PubMed

    Sester, U; Probst, W; Rahmann, H

    1984-01-01

    The ultrastructure of synapses in the stratum fibrosum marginale (SM) of the optic tectum of cichlid fishes (Tilapia mariae) was investigated following acclimation to extreme environmental temperatures (experimental temperatures 16 degrees C and 32 degrees C; preference temperature: 26 degrees C). Four different types of synapses can be differentiated, from which 90% of all synapses belong to axodendritic spine synapses. The general ultrastructural appearance is more distinct in case of cold -adapted fishes, which in particular is due to a more pronounced staining of the polysaccharide-surface coat of the membranes. Analyzing quantitatively the axo-dendritic spine synapses (600 of each collective) significant differences were found for the length of the synaptic contact zone (16 degrees C: 0,391 micron; 32 degrees C: 0,369 micron) and for the thickness of postsynaptic densities (16 degrees C 42,6 nm; 32 degrees C: 52,7 nm). The number of mitochondria per presynapse was rised for cold-adapted animals to a value of 0,29 as compared to 0,18 mitochondria/presynapse for warm-adapted animals. The vesicle density per micron 2 of synaptic area, however, remained unchanged (approximately equal to 89 vesicles/micron 2). The morphological synaptic plasticity thus demonstrated in the optic tectum of chichlid teleosts, is correlated with behavioural changes and with alterations in the biochemical composition of synaptic membranes. PMID:6526994

  13. 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.

  14. 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.

  15. Mitochondrial phylogeny of Chinese barred species of the cyprinid genusAcrossocheilus Oshima, 1919 (Teleostei: Cypriniformes) and its taxonomic implications.

    PubMed

    Yuan, Le-Yang; Liu, Xiao-Xiang; Zhang, E

    2015-01-01

    Sequences from the mitochondrial control region of 14 putative species of Acrossocheilus (Cyprinidae) were examined to elucidate phylogenetic relationships within species of the barred group in that genus. Phylogenetic reconstructions were generated using three tree-building methods: maximum parsimony, maximum likelihood, and Bayesian inference. The resultant phylogenies were consistent with monophyly of the majority of the morphologically recognized species. However, mitochondrial DNA sequence evidence is incongruent with monophyly of A. fasciatus, as currently conceived. This species occurs only in the upper Qiantang-Jiang basin in Zhejiang and Anhui provinces, and coastal rivers in the Zhejiang Province. The species formerly recognized as A. paradoxus from Zhejiang Province is A. fasciatus. The specimens previously reported as A. fasciatus from river basins in Fujian Province are misidentified A. wuyiensis. The barred group of Acrossocheilus is shown to be polyphyletic. Acrossocheilus is restricted to the barred species here placed in "Clade II," containing A. paradoxus and relatives. Separate generic status is recommended for A. monticola and for A. longipinnis and their closest relatives, although more information on phylogenetic relationships based on multiple genes is required to develop robust phylogenetic hypotheses and diagnoses. Masticbarbus Tang, 1942 is available for A. longipinnis and three allied species (A. iridescens, A. microstomus and A. lamus). PMID:26701558

  16. 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.

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

    PubMed Central

    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

    Abstract 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. PMID:24260660

  18. Apistogramma ortegai (Teleostei: Cichlidae), a new species of cichlid fish from the Ampyiacu River in the Peruvian Amazon basin.

    PubMed

    Britzke, Ricardo; Oliveira, Claudio; Kullander, Sven O

    2014-01-01

    Apistogramma ortegai, new species, is described from small streams tributaries of the Ampiyacu River near Pebas, in eastern Peru. It belongs to the Apistogramma regani species group and is distinguished from all other species of Apistogramma by the combination of contiguous caudal spot to bar 7, presence of abdominal stripes, short dorsal-fin lappets in both sexes, absence of vertical stripes on the caudal fin, and reduced number of predorsal and prepelvic scales. PMID:25283927

  19. 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

  20. Isolation and characterization of 13 polymorphic microsatellite loci in Hypostomus ancistroides (Teleostei, Loricariidae) and cross-amplification in related species.

    PubMed

    Galindo, B A; Ferreira, D G; Almeida, F S; Carlsson, J; Sofia, S H

    2015-06-01

    This study details 13 novel polymorphic microsatellite loci in the armoured catfish Hypostomus ancistroides, and assesses their utility for population genetic studies. The analysis of 30 individuals revealed a total of 99 different alleles (ranging from two to 15 alleles per locus), with an average of 762 alleles per locus, with observed and expected heterozygosities ranging from 0103 to 0931 and from 0102 to 0906, respectively. One of the 13 loci showed significant deviations from Hardy-Weinberg equilibrium, probably due to the presence of null alleles, inferred from the excess of homozygotes. PMID:25912318