Sample records for cobitis teleostei cobitidae

  1. Molecular evidence of cryptic diversity in Paracaryophyllaeus (Cestoda: Caryophyllidea), parasites of loaches (Cobitidae) in Eurasia, including description of P. vladkae n. sp.

    PubMed

    Scholz, Tomáš; Oros, Mikuláš; Bazsalovicsová, Eva; Brabec, Jan; Waeschenbach, Andrea; Xi, Bing-Wen; Aydoğdu, Ali; Besprozvannykh, Vladimir; Shimazu, Takeshi; Králová-Hromadová, Ivica; Littlewood, D Timothy J

    2014-12-01

    Molecular phylogenetic analysis of an extensive collection of monozoic tapeworms of the genus Paracaryophyllaeus Kulakovskaya, 1961 (Cestoda: Caryophyllidea), parasites of loaches (Cypriniformes: Cobitidae) in Eurasia, has revealed cryptic species diversity within this long-time monotypic genus, especially in the Paracaryophyllaeus gotoi (Motomura, 1927) species complex [syn. Paracaryophyllaeus dubininorum (Kulakovskaya, 1961); type species]. Three independent, well-supported clades were discovered on the basis of molecular data: (i) specimens from Misgurnus anguillicaudatus and Cobitis lutheri from China, Russian Far East and Japan - called herein P. cf. gotoi 1, which may be conspecific with P. gotoi (Motomura, 1927), although in the absence of sequence data for P. gotoi from its type locality (basin of the River Kumkan in Korea), no certain inferences about their identity can currently be made; (ii) specimens from M. anguillicaudatus from China and Japan - P. cf. gotoi 2, which are morphologically indistinguishable from those of P. cf. gotoi 1; and (iii) morphologically distinct tapeworms from the endemic loach Cobitis bilseli from southwestern Turkey (Beyşehir Lake), which are described herein as a new species. Paracaryophyllaeus vladkae Scholz, Oros and Aydoğdu n. sp. differs from the remaining species of the genus in the following characteristics: the testes begin anterior to the first vitelline follicles (versus posterior), the body is short and robust (versus more elongate and slender), and the scolex is wide, rounded or apically tapered (versus claviform to truncate). Species composition of the genus, host specificity of species and geographical distribution are briefly discussed. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  2. Asexual Reproduction Does Not Apparently Increase the Rate of Chromosomal Evolution: Karyotype Stability in Diploid and Triploid Clonal Hybrid Fish (Cobitis, Cypriniformes, Teleostei)

    PubMed Central

    Majtánová, Zuzana; Choleva, Lukáš; Symonová, Radka; Ráb, Petr; Kotusz, Jan; Pekárik, Ladislav; Janko, Karel

    2016-01-01

    Interspecific hybridization, polyploidization and transitions from sexuality to asexuality considerably affect organismal genomes. Especially the last mentioned process has been assumed to play a significant role in the initiation of chromosomal rearrangements, causing increased rates of karyotype evolution. We used cytogenetic analysis and molecular dating of cladogenetic events to compare the rate of changes of chromosome morphology and karyotype in asexually and sexually reproducing counterparts in European spined loach fish (Cobitis). We studied metaphases of three sexually reproducing species and their diploid and polyploid hybrid clones of different age of origin. The material includes artificial F1 hybrid strains, representatives of lineage originated in Holocene epoch, and also individuals of an oldest known age to date (roughly 0.37 MYA). Thereafter we applied GISH technique as a marker to differentiate parental chromosomal sets in hybrids. Although the sexual species accumulated remarkable chromosomal rearrangements after their speciation, we observed no differences in chromosome numbers and/or morphology among karyotypes of asexual hybrids. These hybrids possess chromosome sets originating from respective parental species with no cytogenetically detectable recombinations, suggesting their integrity even in a long term. The switch to asexual reproduction thus did not provoke any significant acceleration of the rate of chromosomal evolution in Cobitis. Asexual animals described in other case studies reproduce ameiotically, while Cobitis hybrids described here produce eggs likely through modified meiosis. Therefore, our findings indicate that the effect of asexuality on the rate of chromosomal change may be context-dependent rather than universal and related to particular type of asexual reproduction. PMID:26808475

  3. Asexual Reproduction Does Not Apparently Increase the Rate of Chromosomal Evolution: Karyotype Stability in Diploid and Triploid Clonal Hybrid Fish (Cobitis, Cypriniformes, Teleostei).

    PubMed

    Majtánová, Zuzana; Choleva, Lukáš; Symonová, Radka; Ráb, Petr; Kotusz, Jan; Pekárik, Ladislav; Janko, Karel

    2016-01-01

    Interspecific hybridization, polyploidization and transitions from sexuality to asexuality considerably affect organismal genomes. Especially the last mentioned process has been assumed to play a significant role in the initiation of chromosomal rearrangements, causing increased rates of karyotype evolution. We used cytogenetic analysis and molecular dating of cladogenetic events to compare the rate of changes of chromosome morphology and karyotype in asexually and sexually reproducing counterparts in European spined loach fish (Cobitis). We studied metaphases of three sexually reproducing species and their diploid and polyploid hybrid clones of different age of origin. The material includes artificial F1 hybrid strains, representatives of lineage originated in Holocene epoch, and also individuals of an oldest known age to date (roughly 0.37 MYA). Thereafter we applied GISH technique as a marker to differentiate parental chromosomal sets in hybrids. Although the sexual species accumulated remarkable chromosomal rearrangements after their speciation, we observed no differences in chromosome numbers and/or morphology among karyotypes of asexual hybrids. These hybrids possess chromosome sets originating from respective parental species with no cytogenetically detectable recombinations, suggesting their integrity even in a long term. The switch to asexual reproduction thus did not provoke any significant acceleration of the rate of chromosomal evolution in Cobitis. Asexual animals described in other case studies reproduce ameiotically, while Cobitis hybrids described here produce eggs likely through modified meiosis. Therefore, our findings indicate that the effect of asexuality on the rate of chromosomal change may be context-dependent rather than universal and related to particular type of asexual reproduction.

  4. Distinguishing between incomplete lineage sorting and genomic introgressions: complete fixation of allospecific mitochondrial DNA in a sexually reproducing fish (Cobitis; Teleostei), despite clonal reproduction of hybrids.

    PubMed

    Choleva, Lukas; Musilova, Zuzana; Kohoutova-Sediva, Alena; Paces, Jan; Rab, Petr; Janko, Karel

    2014-01-01

    Distinguishing between hybrid introgression and incomplete lineage sorting causing incongruence among gene trees in that they exhibit topological differences requires application of statistical approaches that are based on biologically relevant models. Such study is especially challenging in hybrid systems, where usual vectors mediating interspecific gene transfers--hybrids with Mendelian heredity--are absent or unknown. Here we study a complex of hybridizing species, which are known to produce clonal hybrids, to discover how one of the species, Cobitis tanaitica, has achieved a pattern of mito-nuclear mosaic genome over the whole geographic range. We appplied three distinct methods, including the method using solely the information on gene tree topologies, and found that the contrasting mito-nuclear signal might not have resulted from the retention of ancestral polymorphism. Instead, we found two signs of hybridization events related to C. tanaitica; one concerning nuclear gene flow and the other suggested mitochondrial capture. Interestingly, clonal inheritance (gynogenesis) of contemporary hybrids prevents genomic introgressions and non-clonal hybrids are either absent or too rare to be detected among European Cobitis. Our analyses therefore suggest that introgressive hybridizations are rather old episodes, mediated by previously existing hybrids whose inheritance was not entirely clonal. Cobitis complex thus supports the view that the type of resulting hybrids depends on a level of genomic divergence between sexual species.

  5. DNA content of hepatocyte and erythrocyte nuclei of the spined loach (Cobitis taenia L.) and its polyploid forms.

    PubMed

    Juchno, Dorota; Lackowska, Bozena; Boron, Alicja; Kilarski, Wincenty

    2010-09-01

    We analyzed the DNA content of hepatocyte and erythrocyte nuclei of the spined loach Cobitis taenia (diploid) and its allopolyploid forms. Twenty triploid females and one tetraploid were used. At least 20,000 hepatocyte and erythrocyte nuclei were acquired and analyzed by flow cytometry. C. taenia erythrocyte nuclei contain 3.15 +/- 0.21 pg of DNA and the hepatocyte nuclei 4.45 +/- 0.46 pg of DNA. Triploid Cobitis have 5.08 +/- 0.41 pg of DNA in erythrocyte nuclei and 6.11 +/- 0.40 pg of DNA in hepatocyte nuclei, whereas the tetraploid erythrocyte and hepatocyte nuclei contained 6.60 and 7.40 pg of DNA, respectively. In general, the DNA contents correlate positively with the ploidy level of the fish investigated. The DNA content variation in the hepatocyte and erythrocyte nuclei may be due to differences in extent of chromatin condensation, which is more pronounced in the erythrocyte than hepatocyte nuclei, or to the several orders of ploidy that occur in the parenchymal liver cells.

  6. Quantitative PCR assays for detecting loach minnow (Rhinichthys cobitis) and spikedace (Meda fulgida) in the southwestern United States

    Treesearch

    Joseph C. Dysthe; Kellie J. Carim; Yvette M. Paroz; Kevin S. McKelvey; Michael K. Young; Michael K. Schwartz

    2016-01-01

    Loach minnow (Rhinichthys cobitis) and spikedace (Meda fulgida) are legally protected with the status of Endangered under the U.S. Endangered Species Act and are endemic to the Gila River basin of Arizona and New Mexico. Efficient and sensitive methods for monitoring these species’ distributions are critical for prioritizing conservation efforts. We developed...

  7. Status, distribution and morphometric/meristic characteristics of Cobitis elongata Heckel et Kner 1858 from Slovenia.

    PubMed

    Povz, Meta; Sumer, Suzana

    2003-01-01

    Cobitis elongata Heckel et Kner inhabits the rivers Sava, Kolpa, Krka, Gracnica and Hudinja (the Danube river basin). The species is common in its distribution area. In the Red List of endangered Pisces and Cyclostomata in Slovenia, it is classified as endangered. Status and distribution data of the species from previous reports and recent research were summarized. A total of 31 specimens from the river Kolpa were morphologically studied. Sixteen morphometric and four meristic characteristics were analysed using standard numerical taxonomic techniques. 99.8% of the total variation of standard length was explained by preanal distance, dorsal and ventral fin lengths as well as minimum body height.

  8. Different Histories, Different Destinies‒Impact of Evolutionary History and Population Genetic Structure on Extinction Risk of the Adriatic Spined Loaches (Genus Cobitis; Cypriniformes, Actinopterygii).

    PubMed

    Buj, Ivana; Ćaleta, Marko; Marčić, Zoran; Šanda, Radek; Vukić, Jasna; Mrakovčić, Milorad

    2015-01-01

    The region of Balkans is often considered as an ichthyologic "hot spot", with a great number of species and high portion of endemics living in fresh waters in a relatively small area. The Adriatic watershed in Croatia and Herzegovina is inhabited by six spined loach species (genus Cobitis) whose extinction risk estimations were based solely on their extent of occurrence (and/or area of occupancy) and its fragmentation, and conservation proposals do not consider diversity below species level. In this investigation we employed molecular genetic methods to describe present genetic structure of the Adriatic spined loaches and reveal their demographic history. The divergence of the Adriatic lineages inside the genus Cobitis started in Miocene and lasted until Pleistocene epoch. Geological events responsible for shaping recent diversity of spined loaches in the Adriatic basin are: the Dinarid Mountains upwelling, the evolution of Dinaric Lake system, local tectonic activity, river connections during glaciations and differences in sea level. Even though all the investigated species inhabit karstic rivers located in the same geographic area and that were subject of similar geological events, the results obtained reveal great differences in their genetic diversity and structure and point out the necessity of different conservation measures to ensure their future viability. High level of genetic polymorphism is characteristic for species located more to the south. Two species comprised of more than one population have completely different intraspecific structure; populations of C. illyrica are genetically distinct and represent separate evolutionary significant units, whereas intraspecific structure of C. narentana corresponds to metapopulational pattern. Without population genetic data, evolutionary significant units could be easily misidentified. Furthermore, the obtained results affirm that population genetic measurements are able to detect differences among closely

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

    PubMed

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

    2016-05-12

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

  10. Repeatability of standard metabolic rate (SMR) in a small fish, the spined loach (Cobitis taenia).

    PubMed

    Maciak, Sebastian; Konarzewski, Marek

    2010-10-01

    Significant repeatability of a trait of interest is an essential assumption for undertaking studies of phenotypic variability. It is especially important in studies on highly variable traits, such as metabolic rates. Recent publications suggest that resting/basal metabolic rate of homeotherms is repeatable across wide range of species. In contrast, studies on the consistency of standard metabolic rate (SMR) in ectotherms, particularly fish, are scarce. Here we present a comprehensive analysis of several important technical aspects of body mass-corrected SMR measurements and its repeatability in a small (average weight approximately 3g) fish, the spined loach (Cobitis taenia). First we demonstrated that release of oxygen from the walls of metabolic chambers exposed to hypoxic conditions did not confound SMR measurements. Next, using principle of propagation of measurement uncertainties we demonstrated that in aquatic systems, measurement error is significantly higher in open than closed respirometry setups. The measurement error for SMR of a small fish determined in a closed aquatic system is comparable to that obtainable using top-notch open-flow systems used for air-breathing terrestrial animals. Using a closed respirometer we demonstrated that body mass-corrected SMR in spined loaches was repeatable under both normoxia and hypoxia over a 5-month period (Pearson correlation r=0.68 and r=0.73, respectively) as well as across both conditions (intraclass correlation coefficient tau=0.30). In these analyses we accounted for possible effect of oxygen consumption of the oxygen electrode on repeatability of SMR. Significant SMR consistency was accompanied by significant repeatability of body mass (intraclass correlation coefficient tau=0.86). To our knowledge, this is the first study showing long-term repeatability of body mass and SMR in a small fish, and is consistent with the existence of heritable variation of these two traits. 2010 Elsevier Inc. All rights reserved.

  11. Effective Condition for Whole Testis Cryopreservation of Endangered Miho Spine Loach (Cobitis choii) Through the Optimization of Mud Loach (Misgurnus mizolepis) Whole Testis Cryopreservation Condition.

    PubMed

    Kim, J J; Nam, Y K; Bang, I C; Gong, S P

      BACKGROUND: Miho spine loach (Cobitis choii) is an endangered Korean endemic fish. Whole testis cryopreservation is a good way for species preservation, but needs to the sacrifice of a large number of fish to optimize the freezing condition. Considering this limitation, a surrogate fish species was used for the protocol development. This study was to establish the effective condition for Miho spine loach whole testis cryopreservation by optimizing the conditions for whole testis cryopreservation in an allied species, mud loach (Misgurnus mizolepis). The condition for whole testis cryopreservation was optimized in mud loach first, and then the optimal condition was applied to Miho spine loach testes. The optimal condition for mud loach testis cryopreservation consists of the freezing medium containing 1.3 M dimethyl sulfoxide, 6% fetal bovine serum and 0.3 M trehalose, -1 C/min cooling rate and 26 degree C thawing temperature, which also permits effective cryopreservation of Miho spine loach testes. An effective cryopreservation condition for whole testis of the endangered Miho spine loach has been established by using mud loach as a surrogate fish.

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

    PubMed

    Moritz, Timo; Schliewen, Ulrich K

    2016-06-02

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

  13. Next generation sequencing yields the complete mitochondrial genome of the Hornlip mullet Plicomugil labiosus (Teleostei: Mugilidae).

    PubMed

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

    2016-05-01

    In this study, the complete mitogenome sequence of hornlip mullet Plicomugil labiosus (Teleostei: Mugilidae) has been sequenced by next-generation sequencing method. The assembled mitogenome, consisting of 16,829 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 contains 1057 bp length is located between tRNA-Pro and tRNA-Phe. The overall base composition of P. labiosus is 28.0% for A, 29.3% for C, 15.5% for G and 27.2% for T. The complete mitogenome may provide essential and important DNA molecular data for further population, phylogenetic and evolutionary analysis for Mugilidae.

  14. Next generation sequencing yields the complete mitochondrial genome of the largescale mullet, Liza macrolepis (Teleostei: Mugilidae).

    PubMed

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

    2016-11-01

    In this study, the complete mitogenome sequence of largescale mullet (Teleostei: Mugilidae) has been sequenced by the next-generation sequencing method. The assembled mitogenome, consisting of 16,832 bp, had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs genes, and a non-coding control region of D-loop. D-loop which has a length of 1094 bp is located between tRNA-Pro and tRNA-Phe. The overall base composition of largescale mullet is 27.8% for A, 30.1% for C, 16.2% for G, and 25.9% for T. The complete mitogenome may provide essential and important DNA molecular data for further phylogenetic and evolutionary analysis for Mugilidae.

  15. Hybrid origin of gynogenetic clones and the introgression of their mitochondrial genome into sexual diploids through meiotic hybridogenesis in the loach, Misgurnus anguillicuadatus.

    PubMed

    Yamada, Aya; Kodo, Yukihiro; Murakami, Masaru; Kuroda, Masamichi; Aoki, Takao; Fujimoto, Takafumi; Arai, Katsutoshi

    2015-11-01

    In a few Japanese populations of the loach Misgurnus anguillicaudatus (Teleostei: Cobitidae), clonal diploid lineages produce unreduced diploid eggs that normally undergo gynogenetic reproduction; however the origin of these clones remains elusive. Here, we show the presence of two diverse clades, A and B, within this loach species from sequence analyses of two nuclear genes RAG1 (recombination activating gene 1) and IRBP2 (interphotoreceptor retinoid-binding protein, 2) and then demonstrate heterozygous genotypes fixed at the two loci as the evidence of the hybrid nature of clonal lineages. All the clonal individuals were identified by clone-specific mitochondrial DNA haplotypes, microsatellite genotypes, and random amplified polymorphic DNA fingerprints; they commonly showed two alleles, one from clade A and another from clade B, whereas other wild-type diploids possessed alleles from either clade A or B. However, we also found wild-type diploids with clone-specific mitochondrial DNA and nuclear genes from clade B. One possible explanation is an introgression of a clone-specific mitochondrial genome from clonal to these wild-type loaches. These individuals likely arose by a cross between haploid sperm from bisexual B clade males and haploid eggs with clone-specific mtDNA and clade B nuclear genome, produced by meiotic hybridogenesis (elimination of unmatched A genome followed by meiosis after preferential pairing between two matched B genomes) in clone-origin triploid individual (ABB). © 2015 Wiley Periodicals, Inc.

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

    PubMed

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

    This study explores the relationship between ecomorphology and trophic segregation in four closely related sympatric fish species (Teleostei, Sciaenidae) that are known to differ in their trophic habits. Only adult specimens were analyzed: 103 Cynoscion guatucupa, 77 Pogonias cromis, 61 Micropogonias furnieri, and 48 Menticirrhus americanus. The four species presented divergent ecomorphological traits related to swimming agility, prey spotting and capture, and the potential size of prey they were able to swallow. Results suggest that these sciaenid species can partition the food resources, even though they completely overlap in space. Differences in their ecomorphological traits appear to correlate closely with the diet and consequently could explain the trophic differentiation observed. Arguably, these ecomorphological differences play a significant role in the coexistence of the adults of these sympatric fish species. Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  17. Predation and control efficacies of Misgurnus mizolepis (Cypriniformes: Cobitidae) toward Culex pipiens molestus (Diptera: Culicidae) and fish toxicity of temephos in laboratory and septic tank conditions.

    PubMed

    Chae, Seong Chun; Kwon, Young Hyun; Min, Kyung Il; Kim, Hyung Soo; Kim, Nam-Jin; Kim, Jun-Ran; Son, Bong Gi; Ahn, Young-Joon

    2014-07-01

    Culex pipiens molestus Forskal (Diptera: Culicidae) is the dominant mosquito species in septic tanks in South Korea. An assessment was made of the biological control potential of mud loaches, Misgurnus mizolepis Günther (Cypriniformes: Cobitidae), toward Cx. p. molestus larvae in laboratory and septic tanks. Results were compared with those of temephos 20% emulsifiable concentrate. In laboratory tests, all mud loaches survived on sedimentation chamber- and effluent chamber-collected water of aerobic septic tanks (ASTs), whereas all mud loaches died within 3-12 h after introduction into sedimentation chamber- and effluent chamber-collected water of anaerobic septic tanks, Gill hyperplasia and hemorrhages at the bases of pectoral fins were detected in all dead mud loaches. These appeared to have been caused by bacterial disease, rather than the physical and chemical characteristics of the septic tank water. A mud loach consumed an average range of 1,072-1,058 larvae of Cx. p. molestus in the AST water at 24 h. At the manufacturer's recommended rate (10 ml/ton) in the AST water, the temephos formulation did not cause fish mortality. In the AST experiment, predation of mosquito larvae by mud loaches at a release rate of one fish per 900 mosquito larvae resulted in complete mosquito control from the third day after treatment throughout the 18-wk survey period, compared with temephos 20% emulsifiable concentrate-treated AST water (reduction rate, 40% at 28 days after treatment). Reasonable mosquito control in aerobic septic tanks can be achieved by mosquito breeding season stocking of a rate of one mud loach per 900 mosquito larvae.

  18. Karyological evidence of hybridogenesis in Greenlings (Teleostei: Hexagrammidae).

    PubMed

    Suzuki, Shota; Arai, Katsutoshi; Munehara, Hiroyuki

    2017-01-01

    Two types of natural hybrids were discovered in populations of three Hexagrammos species (Teleostei: Hexagrammidae) distributed off the southern coast of Hokkaido in the North Pacific Ocean. Both hybrids reproduce by hybridogenesis, in which the maternal haploid genome is transmitted to offspring without recombination and the paternal haploid genome is eliminated during gametogenesis. While natural hybrids are unisexual and reproduce hemiclonally by backcrossing with the paternal species (BC-P), artificial F1-hybrids between the pure species produce recombinant gametes. Thus, despite having the same genome composition, the natural hybrids and the F1-hybrids are not genetically identical. Here, to clarify the differences between both hybrids, we examined the karyotypes of the three Hexagrammos species, their natural hybrids, the artificial F1-hybrids, and several backcrosses. Artificial F1-hybrids have karyotypes and chromosome numbers that are intermediate between those of the parental species. Conversely, the natural hybrids differed from F1-hybrids by having several large metacentric chromosomes and microchromosomes. Since the entire maternal haploid genome is inherited by the natural hybrids, maternal backcrosses (BC-M) between natural hybrids and males of the maternal species (H. octogrammus; Hoc) have a hemiclonal Hoc genome with large chromosomes from the mother and a normal Hoc genome from the father. However, the large chromosomes disappear in offspring of BC-M, probably due to fissuring during gametogenesis. Similarly, microsatellite DNA analysis revealed that chromosomes of BC-M undergo recombination. These findings suggest that genetic factors associated with hemiclonal reproduction may be located on the large metacentric chromosomes of natural hybrids.

  19. Histogenesis and disappearance of the teeth of the Mekong giant catfish, Pangasianodon gigas (Teleostei).

    PubMed

    Kakizawa, Yoshiko; Meenakarn, Wanpen

    2003-12-01

    Juveniles of the Mekong giant catfish, Pangasianodon gigas (Teleostei), have 3 sorts of tooth-upper and lower jaw teeth, palatal teeth, and pharyngeal teeth--but adults are toothless. To investigate the histogenesis and disappearance of the teeth, we made serial sections of the mouth and teeth of juvenile fish at 10 developmental stages (from ca. 8.5 to ca. 30 cm in total length) and examined them under scanning electron microscope and light microscope. Observations of teeth and surrounding tissues in the serial sections revealed the process of tooth resorption by active odontoclast-like cells. Numbers of jaw and palatal teeth decreased with age. When the fish reached ca. 14 cm in total length, the numbers of functional upper jaw teeth and successional tooth germs decreased rapidly, and the developmental rate of successional tooth germs slowed. When the fish reached ca. 24 cm, no teeth existed in the upper jaw. It is clear that tooth disappearance results from the shedding of functional teeth and the lack of replacement tooth germs.

  20. Next generation sequencing yields the complete mitochondrial genome of the flathead mullet, Mugil cephalus cryptic species NWP2 (Teleostei: Mugilidae).

    PubMed

    Shen, Kang-Ning; Yen, Ta-Chi; Chen, Ching-Hung; Li, Huei-Ying; Chen, Pei-Lung; Hsiao, Chung-Der

    2016-05-01

    In this study, the complete mitogenome sequence of Northwestern Pacific 2 (NWP2) cryptic species of flathead mullet, Mugil cephalus (Teleostei: Mugilidae) has been amplified by long-range PCR and sequenced by next-generation sequencing method. The assembled mitogenome, consisting of 16,686 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 was 909 bp length and was located between tRNA-Pro and tRNA-Phe. The overall base composition of NWP2 M. cephalus was 28.4% for A, 29.8% for C, 26.5% for T and 15.3% for G. The complete mitogenome may provide essential and important DNA molecular data for further phylogenetic and evolutionary analysis for flathead mullet species complex.

  1. Genomic replacement of native Cobitis lutheri with introduced C. tetralineata through a hybrid swarm following the artificial connection of river systems

    PubMed Central

    Kwan, Ye-Seul; Ko, Myeong-Hun; Won, Yong-Jin

    2014-01-01

    River connections via artificial canals will bring about secondary contacts between previously isolated fish species. Here, we present a genetic consequence of such a secondary contact between Cobitis fish species, C. lutheri in the Dongjin River, and C. tetralineata in the Seomjin River in Korea. The construction of water canals about 80 years ago has unidirectionally introduced C. tetralineata into the native habitat of C. lutheri, and then these species have hybridized in the main stream section of the Dongjin River. According to the divergence population genetic analyses of DNA sequence data, the two species diverged about 3.3 million years ago, which is interestingly coincident with the unprecedented paleoceanographic change that caused isolations of the paleo-river systems in northeast Asia due to sea-level changes around the late Pliocene. Multilocus genotypic data of nine microsatellites and three nuclear loci revealed an extensively admixed structure in the hybrid zone with a high proportion of various post-F1 hybrids. Surprisingly, pure native C. lutheri was absent in the hybrid zone in contrast to the 7% of pure C. tetralineata. Such a biased proportion must have resulted from the dominant influence of continually introducing C. tetralineata on the native C. lutheri which has no supply of natives from other tributaries to the hybrid zone due to numerous low-head dams. In addition, mating experiments indicated that there is no discernible reproductive isolation between them. All the results suggest that the gene pool of native C. lutheri is being rapidly replaced by that of continually introducing C. tetralineata through a hybrid swarm for the last 80 years, which will ultimately lead to the genomic extinction of natives in this hybrid zone. PMID:24834340

  2. 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.

  3. Heterochrony in fringeheads (Neoclinus) and amplification of an extraordinary aggressive display in the Sarcastic Fringehead (Teleostei: Blenniiformes).

    PubMed

    Hongjamrassilp, Watcharapong; Summers, Adam P; Hastings, Philip A

    2018-05-01

    The Sarcastic Fringehead (Neoclinus blanchardi, Teleostei) exhibits an extreme version of a common aggressive display, the "gaping display," in which an open mouth is presented toward an opponent. Males of this species have extremely long jaws that extend posteriorly well past the posterior margin of the head and are flared laterally during the gaping display. In this study, we explored morphological traits related to this extraordinary display in this and related species of blennies. Morphological modifications include enlargement of the buccopalatal membrane, elongation of the maxilla via an uncalcified posterior extension, and evolution of a novel hinge between the anterior maxilla and lacrimal bones permitting lateral movement of the upper jaw. Geometric morphometry using the truss network system, thin-plate spline, and PCA of three closely related species of Neoclinus indicate that the elongate maxilla of N. blanchardi most likely evolved via acceleration (faster growth compared to outgroups) and hypermorphosis (continued growth to a larger body size), both forms of peramorphic heterochrony. Coloration and fluorescence of the buccopalatal membrane may also serve to amplify the extraordinary gaping display of the Sarcastic Fringehead. © 2018 Wiley Periodicals, Inc.

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

    PubMed

    Angulo, Arturo; López-Sánchez, Myrna I

    2017-02-23

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

  5. Evolutionary history of freshwater sculpins, genus Cottus (Teleostei; Cottidae) and related taxa, as inferred from mitochondrial DNA phylogeny.

    PubMed

    Yokoyama, Ryota; Goto, Akira

    2005-09-01

    The freshwater sculpins, genus Cottus (Teleostei; Cottidae), comprise bottom-dwelling fishes that exhibit various life-history styles, having radiated throughout Northern Hemisphere freshwater habitats. The phylogenetic relationships among Cottus and related taxa were estimated from mitochondrial DNA 12S rRNA and control region (CR) sequences, the freshwater sculpins examined falling into five lineages (A-E). Lineage A consisted of Trachidermus fasciatus and C. kazika, both having a catadromous life-history. The remaining species (lineages B-E) spawn in freshwater habitats regardless of life-history (amphidromous, lacustrine or fluvial), suggesting that the various life-history types post-dated a common ancestor of lineages B-E. Molecular clock estimates suggested a Pliocene-Pleistocene radiation (or Miocene-Pliocene from the alternative clock) of lineages B-E. In eastern Eurasia, speciation with life-history changes to amphidromous or fluvial styles has apparently occurred independently in some lineages, as a general pattern. Mitochondrial DNA CR phylogeny showed the monophyletic Baikalian cottoids (Cottoidei) to be nested within Cottus and Trachidermus, suggesting that the former ecologically and morphologically divergent cottoids may have originated from a single lineage which invaded the ancient lake.

  6. Dactylogyrid monogeneans parasitising Cyphocharax voga (Hensel) (Teleostei: Curimatidae) from the Pampas region, Argentina: new and previously described species.

    PubMed

    Rossin, María Alejandra; Timi, Juan Tomás

    2016-09-01

    Most studies on dactylogyrid monogeneans in Argentina have been carried out during 1980s and 1990s. Many of these species have been later synonymised and other remain under a confusing taxonomic status, particularly those parasitising Cyphocharax voga (Hensel) (Teleostei: Curimatidae). In order to clarify the identity of dactylogyrids, new material was collected from fishes in Lake Chascomús, Buenos Aires Province, Argentina. A total of four species was found in the gills of C. voga. Two known species, Curvianchoratus singularis (Suriano, 1980) Suriano, 1986 and Palombitrema triangulum (Suriano, 1981) Suriano, 1997, are redescribed and their generic and specific status discussed, and two new species are described. Urocleidoides surianoae n. sp. can be distinguished from its congeners by having an anterior medial projection in the ventral bar and a laminar ligament connecting the base of the male copulatory organ and accessory piece. Annulotrematoides bonaerensis n. sp. differs from its congeners principally by having a ventral bar with an anterior medial projection. The diversity of dactylogyrids harboured by C. voga indicates the need of further studies in the Pampas region, which will provide interesting and valuable sources of evidence for future zoogeographical and evolutionary research on dactylogyrids in the Neotropics.

  7. 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.

  8. 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

  9. The Gastric Phenotype in the Cypriniform Loaches: A Case of Reinvention?

    PubMed Central

    Gonçalves, Odete; Castro, L. Filipe C.; Smolka, Adam J.; Fontainhas, António

    2016-01-01

    The stomach, which is characterized by acid peptic digestion in vertebrates, has been lost secondarily multiple times in the evolution of the teleost fishes. The Cypriniformes are largely seen as an agastric order; however, within the superfamily Cobitoidea, the closely related sister groups Nemacheilidae and Balitoridae have been identified as gastric families. The presence of these most recently diverged gastric families in an otherwise agastric clade indicates that either multiple (>2–3) loss events occurred with the Cyprinidae, Catostomidae and Cobitidae, or that gastric reinvention arose in a recent ancestor of the Nemacheilidae/Balitoridae sister clade. In the present study, the foregut regions of Cobitidae, Nemacheilidae/Balitoridae and the ancestral Botiidae family members were examined for the presence of gastric glands and gastric proton pump (Atp4a) α subunit expression by histology and immunohistochemistry respectively. Atp4a gene expression was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR). Gastric glands expressing apical H+/K+-ATPase α subunit and isolated partial sequences of atp4a, identified using degenerate primers showing clear orthology to other vertebrate atp4a sequences, were detected in representative species from Nemacheilidae/ Balitoridae and Botiidae, but not Cobitidae (Misgurnus anguillicaudatus). In summary, we provide evidence for an uninterrupted gastric evolutionary lineage in the Cobitoidea, making it highly improbable that the stomach was reinvented in the Nemacheilidae/Balitoridae clade consistent with Dollo’s principle. These results also indicate that the gastric trait may be present elsewhere in the Cobitoidea. PMID:27783698

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

    PubMed

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

    2004-02-01

    This study focuses on the consequences of the switch of tactic from parasitic to parental male in the black goby, Gobius niger (Teleostei: Gobiidae), a species showing two alternative male mating tactics. Older and larger males defend nests, court, and perform parental care on eggs, while younger and smaller ones behave as parasites, sneaking into nests while spawning occurs. Males adopting different tactics are known to present differences in primary and secondary sex traits. The social context of sneaker males was manipulated to induce a tactic switch. Sneakers were kept under two different experimental treatments with or without a female, and under exclusion of male-male competition. Males changed tactics, courting females, spawning, and performing parental care. All males showed substantial changes in primary sexual traits, such as a reduction in gonadal development and an increase in the investment in accessory structures. The experimental groups differed in the functionality of gonads and accessory organs and in the development of the secondary sex traits. These results demonstrate that the moment of switching is not genetically fixed in the black goby. Sneaker males are able to quickly reallocate energy in primary and secondary sex traits, in accordance with the adopted tactic. Several aspects of this flexible reproductive pattern resemble the socially controlled sex change found in sequential hermaphrodites. Copyright 2004 Wiley-Liss, Inc.

  11. Comparative morphology and cytology of the male sperm-transmission organs in viviparous species of clinid fishes (Clinidae: Teleostei, Perciformes).

    PubMed

    Fishelson, Lev; Gon, Ofer; Holdengreber, Vered; Delarea, Yakob

    2006-12-01

    This work comprises the first comparative study of the morphology and cytology of the sperm transmission organs in males of 14 species of viviparous clinid fishes (Clinidae, Blennioidei, Teleostei). The form and dimensions of these organs differ among the various species studied. The organs are composed of intra-abdominal ampullae, into which the sperm ducts and urinary bladder anchor, and an external protruding intromittent papilla used for insemination. The form of the ampullae differs among the various species, from pear-shaped to horseshoe-shaped. It increases in dimensions with increasing length of the male. In all the species this organ is covered by a connective-tissue tunic that encompasses both circular and longitudinal striated muscle bundles. The lumina of the ampullae harbor the epididymis, a strongly convoluted and plicated duct, which becomes filled with spermatozeugmata during reproduction. From here, the epididymis continues into the protruding intromittent papillae, where its folds gradually straighten at the apical part of the intromittent organ. The form and dimensions of this copulatory organ also differ in the various species. Papillae bearing taste buds are found on the apical parts of the intromittent organ, and it is probable that these, together with the difference in forms of the organ, help to prevent interspecific copulation. Copyright 2006 Wiley-Liss, Inc.

  12. Action of the Metalloproteinases in Gonadal Remodeling during Sex Reversal in the Sequential Hermaphroditism of the Teleostei Fish Synbranchus marmoratus (Synbranchiformes: Synbranchidae)

    PubMed Central

    Mazzoni, Talita Sarah; Lo Nostro, Fabiana Laura; Antoneli, Fernanda Natália; Quagio-Grassiotto, Irani

    2018-01-01

    Teleostei present great plasticity regarding sex change. During sex reversal, the whole gonad including the germinal epithelium undergoes significant changes, remodeling, and neoformation. However, there is no information on the changes that occur within the interstitial compartment. Considering the lack of information, especially on the role played by metalloproteinases (MMPs) in fish gonadal remodeling, the aim of this study was to evaluate the action of MMPs on gonads of sex reversed females of Synbranchus marmoratus, a fresh water protogynic diandric fish. Gonads were processed for light microscopy and blood samples were used for the determination of plasma sex steroid levels. During sex reversal, degeneration of the ovaries occurred and were gradually replaced by the germinal tissue of the male. The action of the MMPs induces significant changes in the interstitial compartment, allowing the reorganization of germinal epithelium. Leydig cells also showed an important role in female to male reversion. The gonadal transition coincides with changes in circulating sex steroid levels throughout sex reversion. The action of the MMPs, in the gonadal remodeling, especially on the basement membrane, is essential for the establishment of a new functional germinal epithelium. PMID:29695033

  13. 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. (c) 2004 Wiley-Liss, Inc.

  14. Hair Cell Heterogeneity in the Goldfish Saccule

    NASA Technical Reports Server (NTRS)

    Saidel, William M.; Lanford, Pamela J.; Yan, Hong Y.; Popper, Arthur N.

    1995-01-01

    A set of cytological studies performed in the utricle and saccule of Astronotus ocellatus (Teleostei, Percomorphi, Cichlidae) identified two basic types of hair cells and others with some intermediate characteristics. This paper reports on applying the same techniques to the saccule of Carassius auratus (Teleostei, Otophysi, Cyprinidae) and demonstrates similar types of hair cells to those found in Astronotus. Since Carassius and Astronous are species of extreme taxonomic distance within the Euteteostei, two classes of mechanoreceptive hair cells are likely to represent the primitive condition for sensory receptors in the euteleost inner ear and perhaps in all bony fish ears.

  15. 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

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

    PubMed

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

    2013-12-01

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

  17. eDNA sampling: Not just for fisheries biologists anymore

    Treesearch

    Michael Schwartz; Brooke Penaluna; Taylor Wilcox

    2017-01-01

    The use of eDNA sampling for fish and amphibian monitoring is widely known. Fisheries biologists, in particular, have embraced the eDNA revolution. Over 150 papers in the published literature used sampled water for the detection of everything from minnows (Rhinichthys cobitis and Meda fulgida; Dysthe et al. 2017) to whale sharks (Rhincodon typus; Sigsgaard et al. 2016...

  18. A new species of Myxozoa, Henneguya rondoni n. sp. (Myxozoa), from the peripheral nervous system of the Amazonian fish, Gymnorhamphichthys rondoni (Teleostei).

    PubMed

    Azevedo, Carlos; Casal, Graça; Matos, Patricia; Matos, Edilson

    2008-01-01

    Henneguya rondoni n. sp. found in the peripheral lateral nerves located below the two lateral lines of the fish Gymnorhamphichthys rondoni (Teleostei, Rhamphichthyidae) from the Amazon river is described using light and electron microscopy. Spherical to ellipsoid cysts measuring up to 110 microm in length contained only immature and mature spores located in close contact with the myelin sheaths of the nervous fibres. Ellipsoidal spores measured 17.7 (16.9-18.1)-microm long, 3.6 (3.0-3.9)-microm wide, and 2.5 (2.2-2.8)-microm (n=25) thick. The spore body measuring 7.0 (6.8-7.3)-microm long was formed by two equal symmetric valves, each with an equal tapering tail 10.7 (10.3-11.0) microm in length. The tails were composed of an internal dense material surrounded by an external homogeneous sheath of hyaline substance. The valves surrounded two equal pyriform polar capsules measuring 2.5 (2.2-2.8)-microm long and 0.85 (0.79-0.88)-microm (n=25) wide and a binucleated sporoplasm cell containing globular sporoplasmosomes 0.38 (0.33-0.42) microm (n=25) in diam. with an internal eccentric dense structure with half-crescent section. Each polar capsule contains an anisofilar polar filament with 6-7 turns obliquely to the long axis. The matrix of the polar capsule was dense and the wall filled with a hyaline substance. The spores differed from those of previously described species. Based on the ultrastructural morphology of the spore and specificity to the host species, we propose a new species name H. rondoni n. sp.

  19. The Jaw Adductor Muscle Complex in Teleostean Fishes: Evolution, Homologies and Revised Nomenclature (Osteichthyes: Actinopterygii)

    PubMed Central

    Datovo, Aléssio; Vari, Richard P.

    2013-01-01

    The infraclass Teleostei is a highly diversified group of bony fishes that encompasses 96% of all species of living fishes and almost half of extant vertebrates. Evolution of various morphological complexes in teleosts, particularly those involving soft anatomy, remains poorly understood. Notable among these problematic complexes is the adductor mandibulae, the muscle that provides the primary force for jaw adduction and mouth closure and whose architecture varies from a simple arrangement of two segments to an intricate complex of up to ten discrete subdivisions. The present study analyzed multiple morphological attributes of the adductor mandibulae in representatives of 53 of the 55 extant teleostean orders, as well as significant information from the literature in order to elucidate the homologies of the main subdivisions of this muscle. The traditional alphanumeric terminology applied to the four main divisions of the adductor mandibulae – A1, A2, A3, and Aω – patently fails to reflect homologous components of that muscle across the expanse of the Teleostei. Some features traditionally used as landmarks for identification of some divisions of the adductor mandibulae proved highly variable across the Teleostei; notably the insertion on the maxilla and the position of muscle components relative to the path of the ramus mandibularis trigeminus nerve. The evolutionary model of gain and loss of sections of the adductor mandibulae most commonly adopted under the alphanumeric system additionally proved ontogenetically incongruent and less parsimonious than a model of subdivision and coalescence of facial muscle sections. Results of the analysis demonstrate the impossibility of adapting the alphanumeric terminology so as to reflect homologous entities across the spectrum of teleosts. A new nomenclatural scheme is proposed in order to achieve congruence between homology and nomenclature of the adductor mandibulae components across the entire Teleostei. PMID

  20. Trophic relationships, feeding habits and seasonal dietary changes in an intertidal rockpool fish assemblage in the Gulf of Cadiz (NE Atlantic)

    NASA Astrophysics Data System (ADS)

    Compaire, Jesus C.; Cabrera, Remedios; Gómez-Cama, Carmen; Soriguer, Milagrosa C.

    2016-06-01

    This paper describes the use of resources and diet of nine resident fish species in the rocky intertidal zone of the Gulf of Cadiz and examines whether their populations are affected by trophic competition. A stomach content analysis of the nine species revealed that only one was herbivorous (Parablennius sanguinolentus), while the rest were mainly carnivorous (Gobius bucchichi, Gobius cobitis, Gobius paganellus, Zebrus zebrus, Salaria pavo, Lepadogaster lepadogaster, Scorpaena porcus and Tripterygion tripteronotum). The most frequently consumed prey were amphipods, isopods, polychaetes, decapods, chironomids, tanaidaceans, gastropods, copepods, cumaceans and ostracods. In most species, the occurrence of polychaetes and molluscs was higher in the cold season, whereas that of isopods, decapods, chironomids and fish increased in the warm season. In general, larger specimens consumed larger prey, with an increase in the occurrence of isopods, decapods and fish. An analysis of trophic niche breadth defined G. cobitis as generalist, G. bucchichi as opportunist and S. porcus as specialist, whereas the values obtained for the other species did not indicate a clearly defined strategy. Low diet overlap values and the segregation observed in several analyses indicated an adequate distribution of resources.

  1. Neopterygian phylogeny: the merger assay

    PubMed Central

    Sferco, Emilia

    2018-01-01

    The phylogenetic relationships of the recently described genus †Ticinolepis from the Middle Triassic of the Monte San Giorgio are explored through cladistic analyses of the so far largest morphological dataset for fossil actinopterygians, including representatives of the crown-neopterygian clades Halecomorphi, Ginglymodi and Teleostei, and merging the characters from previously published systematic studies together with newly proposed characters. †Ticinolepis is retrieved as the most basal Ginglymodi and our results support the monophyly of Teleostei and Holostei, as well as Halecomorphi and Ginglymodi within the latter clade. The patterns of relationships within these clades mostly agree with those of previous studies, although a few important differences require future research. According to our results, ionoscopiforms are not monophyletic, caturids are not amiiforms and leptolepids and luisiellids form a monophyletic clade. Our phylogenetic hypothesis confirms the rapid radiation of the holostean clades Halecomorphi and Ginglymodi during the Early and Middle Triassic and the radiation of pholidophoriform teleosts during the Late Triassic. Crown-group Halecomorphi have an enormous ghost lineage throughout half of the Mesozoic, but ginglymodians and teleosts show a second radiation during the Early Jurassic. The crown-groups of Halecomorphi, Ginglymodi and Teleostei originated within parallel events of radiation during the Late Jurassic. PMID:29657820

  2. Neopterygian phylogeny: the merger assay

    NASA Astrophysics Data System (ADS)

    López-Arbarello, Adriana; Sferco, Emilia

    2018-03-01

    The phylogenetic relationships of the recently described genus †Ticinolepis from the Middle Triassic of the Monte San Giorgio are explored through cladistic analyses of the so far largest morphological dataset for fossil actinopterygians, including representatives of the crown-neopterygian clades Halecomorphi, Ginglymodi and Teleostei, and merging the characters from previously published systematic studies together with newly proposed characters. †Ticinolepis is retrieved as the most basal Ginglymodi and our results support the monophyly of Teleostei and Holostei, as well as Halecomorphi and Ginglymodi within the latter clade. The patterns of relationships within these clades mostly agree with those of previous studies, although a few important differences require future research. According to our results, ionoscopiforms are not monophyletic, caturids are not amiiforms and leptolepids and luisiellids form a monophyletic clade. Our phylogenetic hypothesis confirms the rapid radiation of the holostean clades Halecomorphi and Ginglymodi during the Early and Middle Triassic and the radiation of pholidophoriform teleosts during the Late Triassic. Crown-group Halecomorphi have an enormous ghost lineage throughout half of the Mesozoic, but ginglymodians and teleosts show a second radiation during the Early Jurassic. The crown-groups of Halecomorphi, Ginglymodi and Teleostei originated within parallel events of radiation during the Late Jurassic.

  3. Installation Summaries From the FY 2001 Survey of Threatened and Endangered Species on Army Lands

    DTIC Science & Technology

    2002-08-01

    lepard frog Amphibian PT Rhinichthys cobitis Loach minnow Fish T Sarracenia oreophilia Green pitcher-plant Plant E Sarracenia rubra alabamensis...Alabama canebrake pitcher-plant Plant E Sarracenia rubra spp. Jonesii Moutain sweet pitcher-plant Plant E Schiedea adamantis Ma`oli`oli Plant E...Isotria medeoloides Small whorled pogonia Onsite T Plant No Sarracenia oreophilia Green pitcher-plant Onsite E Plant No A-11 MACOM

  4. The Environmental Assessment and Management (TEAM) Guide: New Mexico Supplement

    DTIC Science & Technology

    2010-03-01

    dace, Phoxinus erythrogaster (j) Colorado pikeminnow, Ptychocheilus lucius (k) loach minnow, Tiaroga cobitis 5-13 Natural Resources Management...writing by the Department, off-site at a readily available location. ST.4.38.NM. Corrective actions must be ta ken u pon a release involving a...cause a public nuisance or threat to human health, safety and welfare, or the environment. Verify th at when c ontaminated s oil is ta ken o ff s ite

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

    PubMed

    Paladini, Giuseppe; Huyse, Tine; Shinn, Andrew P

    2011-06-09

    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. 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). The ability of G. salinae n. sp. to tolerate a wide range of salinities and temperatures shows its

  6. 75 FR 75913 - Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Vermilion...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-07

    ... the comment period until July 29, 2010, as well as announcing the availability of a draft economic... chermocki (Teleostei: Percidae)) was officially described in 1992 from Turkey Creek, a tributary of the... small pronounced mouth. The vermilion darter is a medium-sized darter, reaching about 7.1 centimeters (2...

  7. The complete mitochondrial genome of Ambastaia sidthimunki (Cypriniformes: Cobitidae).

    PubMed

    Yu, Peng; Wei, Min; Yang, Qichao; Yang, Yingming; Wan, Quan

    2016-09-01

    Ambastaia sidthimunki is a beautiful small-sized fish and it was categorized as Endangered B2ab (iii,v) in the IUCN Red List. In this study, we reported the complete mitochondrial genome of the A. sidthimunki. The mitochondrial genome sequence was a circular molecule with 16,574 bp in length, and it contained 2 ribosomal RNA genes, 22 transfer RNA genes, 13 protein-coding genes, an L-strand replication origin (OL) and a control region (D-loop). The nucleotide acid composition of the entire mitogenome was 26.94% for C, 15.55% for G, 31.84% for A and 25.67% for T, with an AT content of 57.51%. This research contributes new molecular data for the conservation of this Endangered species.

  8. Non-invasive ancient DNA protocol for fluid-preserved specimens and phylogenetic systematics of the genus Orestias (Teleostei: Cyprinodontidae).

    PubMed

    Garrigos, Yareli Esquer; Hugueny, Bernard; Koerner, Kellie; Ibañez, Carla; Bonillo, Celine; Pruvost, Patrice; Causse, Romain; Cruaud, Corinne; Gaubert, Philippe

    2013-01-01

    Specimens stored in museum collections represent a crucial source of morphological and genetic information, notably for taxonomically problematic groups and extinct taxa. Although fluid-preserved specimens of groups such as teleosts may constitute an almost infinite source of DNA, few ancient DNA protocols have been applied to such material. In this study, we describe a non-invasive Guanidine-based (GuSCN) ancient DNA extraction protocol adapted to fluid-preserved specimens that we use to re-assess the systematics of the genus Orestias (Cyprinodontidae: Teleostei). The latter regroups pupfishes endemic to the inter-Andean basin that have been considered as a 'species flock', and for which the morphology-based taxonomic delimitations have been hotly debated. We extracted DNA from the type specimens of Orestias kept at the Muséum National d'Histoire Naturelle of Paris, France, including the extinct species O. cuvieri. We then built the first molecular (control region [CR] and rhodopsin [RH]) phylogeny including historical and recently collected representatives of all the Orestias complexes as recognized by Parenti (1984a): agassizii, cuvieri, gilsoni and mulleri. Our ancient DNA extraction protocol was validated after PCR amplification through an approach based on fragment-by-fragment chimera detection. After optimization, we were able to amplify < 200 bp fragments from both mitochondrial and nuclear DNA (CR and RH, respectively) from probably formalin-fixed type specimens bathed entirely in the extraction fluid. Most of the individuals exhibited few modifications of their external structures after GuSCN bath. Our approach combining type material and 'fresh' specimens allowed us to taxonomically delineate four clades recovered from the well-resolved CR tree into four redefined complexes: agassizii (sensu stricto, i.e. excluding luteus-like species), luteus, cuvieri and gilsoni. The mulleri complex is polyphyletic. Our phylogenetic analyses based on both

  9. A revision of the spirit loaches, genus Lepidocephalus (Cypriniformes, Cobitidae).

    PubMed

    Deein, Gridsada; Tangjitjaroen, Weerapongse; Page, Lawrence M

    2014-03-17

    Lepidocephalus has been assumed to include only two species and confined to peninsular Malaysia and Indonesia. However, based on records and collections reported herein, the genus contains five species and is most common in the Chao Phraya basin of Thailand. Large rivers seem to be the preferred habitat, and difficulty in collecting these rivers may account for the paucity of specimens in collections. The known range of these five species includes western and southern Borneo, Java, Sumatra, peninsular Malaysia, and central Thailand.

  10. Food resource utilization of the skates Rioraja agassizii (Müller & Henle, 1841) and Psammobatis extenta (Garman, 1913) on the continental shelf off Ubatuba, South-eastern Brazil.

    PubMed

    Muto, E Y; Soares, L S; Goitein, R

    2001-05-01

    The feeding habits of Rioraja agassizii (syn. Raja agassizii) and Psammobatis extenta (syn. Psammobatis glansdissimilis) of the South-eastern Brazilian coast were studied by means of stomach content analysis. The samples were obtained on eight seasonal oceanographic cruises, carried out between October 1985 and July 1987. The importance of each food item was evaluated on the basis of the Index of Relative Importance and the feeding similarity by Percentage of Similarity. The results indicated that both species are benthic feeders, preying mainly on Crustacea, especially Amphipoda, Caridea and Brachyura. Teleostei were also important for R. agassizii. Seasonal variation of the diet seems to be associated with the availability of the prey, whose distribution and abundance are related to the dynamics of the water masses of the region. Juveniles and adults of P. extenta exploited the same resources while juveniles and adults of R. agassizii presented low diet similarity during most of the year. Caridea were an important food for all length classes of R. agassizii, while Amphipoda were for smaller specimens, and Teleostei for larger ones. The feeding overlap between the two species was higher during autumn 1986, winter 1986 and winter 1987.

  11. Feeding habits of an endemic fish, Oxygymnocypris stewartii, in the Yarlung Zangbo River in Tibet, China

    USGS Publications Warehouse

    Huo, Bin; Xie, Cong Xin; Madenjian, Charles P.; Ma, Bao Shan; Yang, Xue Feng; Huang, Hai Ping

    2014-01-01

    Feeding habits of Oxygymnocypris stewartii were investigated based on monthly sampling in the Yarlung Zangbo River from August 2008 to August 2009. The gut contents of 194 individuals were analysed and quantified with numerical and gravimetric methods. This species can be considered a generalized and opportunistic predator feeding both on teleosts and aquatic insects. A multivariate analysis revealed noticeable variation in O. stewartii diet composition with fish size and season. The smaller specimens fed primarily on Cobitidae and Hydropsychidae. As they grew, Cyprinidae and Chironomidae larvae became important prey. The preferred food items were teleosts in summer and autumn. For winter and spring, the predominant prey switched to chironomidae larvae. Diet composition did not significantly vary between the sexes. Finally, a significant and positive correlation between predator and prey length was found. These findings provide the fundamental information better understanding the role of this important endemic species in the Yarlung Zangbo River food web.

  12. Evolution of caudal fin ray development and caudal fin hypural diastema complex in spotted gar, teleosts, and other neopterygian fishes.

    PubMed

    Desvignes, Thomas; Carey, Andrew; Postlethwait, John H

    2018-06-01

    The caudal fin of actinopterygians transitioned from a heterocercal dorsoventrally asymmetrical fin to a homocercal externally symmetrical fin in teleosts through poorly understood evolutionary developmental mechanisms. We studied the caudal skeleton of major living actinopterygian lineages, including polypteriformes, acipenseriformes, Holostei (gars and bowfin), and teleosts, compared with reports of extinct neopterygians and basal teleosteans. We focused on the hypural diastema complex, which includes (1) a gap between hypurals 2 and 3, that (2) separates two plates of connective tissue at (3) the branching of caudal vasculature; these features had been considered as a shared, derived trait of teleosts, a synapomorphy. These studies revealed that gars and teleosts share all three features of the hypural diastema complex. Absence of a complex with these features from bowfin, fossil Holostei, and stem Teleostei argues in favor of repetitive, independent emergence in several neopterygian and basal Teleostei lineages, or less likely, many independent losses. We further observed that, in gars and teleosts, the earliest developing lepidotrichia align with the horizontal adult body axis, thus participating in external symmetry. These results suggest that the hypural diastema complex in teleosts and gars represents a homoplasy among neopterygians and that it emerged repeatedly by parallel evolution due to shared inherited underlying genetic and developmental programs (latent homology). Because the hypural diastema complex exists in gars with heterocercal tails, this complex is independent of homocercality. Developmental Dynamics 247:832-853, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

  13. Transcriptome characterization and SSR discovery in large-scale loach Paramisgurnus dabryanus (Cobitidae, Cypriniformes).

    PubMed

    Li, Caijuan; Ling, Qufei; Ge, Chen; Ye, Zhuqing; Han, Xiaofei

    2015-02-25

    The large-scale loach (Paramisgurnus dabryanus, Cypriniformes) is a bottom-dwelling freshwater species of fish found mainly in eastern Asia. The natural germplasm resources of this important aquaculture species has been recently threatened due to overfishing and artificial propagation. The objective of this study is to obtain the first functional genomic resource and candidate molecular markers for future conservation and breeding research. Illumina paired-end sequencing generated over one hundred million reads that resulted in 71,887 assembled transcripts, with an average length of 1465bp. 42,093 (58.56%) protein-coding sequences were predicted; and 43,837 transcripts had significant matches to NCBI nonredundant protein (Nr) database. 29,389 and 14,419 transcripts were assigned into gene ontology (GO) categories and Eukaryotic Orthologous Groups (KOG), respectively. 22,102 (31.14%) transcripts were mapped to 302 KEGG pathways. In addition, 15,106 candidate SSR markers were identified, with 11,037 pairs of PCR primers designed. 400 primers pairs of SSR selected randomly were validated, of which 364 (91%) pairs of primers were able to produce PCR products. Further test with 41 loci and 20 large-scale loach specimens collected from the four largest lakes in China showed that 36 (87.8%) loci were polymorphic. The transcriptomic profile and SSR repertoire obtained in this study will facilitate population genetic studies and selective breeding of large-scale loach in the future. Copyright © 2015. Published by Elsevier B.V.

  14. Reproduction and recruitment of sympatric fish species on an intertidal rocky shore.

    PubMed

    Compaire, J C; Casademont, P; Gómez-Cama, C; Soriguer, M C

    2018-02-01

    The reproductive cycle of seven common species (Gobius paganellus, Gobius bucchichi, Gobius cobitis, Parablennius sanguinolentus, Salaria pavo, Tripterygion tartessicum and Symphodus roissali) on rocky shores in the Gulf of Cadiz and their relationship with the sea surface temperature (SST) is analysed. Partial data on Scorpaena porcus are also given. Fecundity of these short lifespan species shows a positive linear correlation between the number of oocytes and an increase in female size. Spawnings are concentrated in the first 7 months of the year. An analysis of reproductive growth with respect to SST shows that water temperature in the winter months affects the timing of the onset of reproduction in most species. Recruitment is takes place throughout the year, but a temporal segregation within different families occurs in their spawning as well as recruitment. © 2017 The Fisheries Society of the British Isles.

  15. A genomic view of the NOD-like receptor family in teleost fish: Identification of a novel NLR subfamily in zebrafish

    USGS Publications Warehouse

    Laing, K.J.; Purcell, M.K.; Winton, J.R.; Hansen, J.D.

    2008-01-01

    Background. A large multigene family of NOD-like receptor (NLR) molecules have been described in mammals and implicated in immunity and apoptosis. Little information, however, exists concerning this gene family in non-mammalian taxa. This current study, therefore, provides an in-depth investigation of this gene family in lower vertebrates including extensive phylogenetic comparison of zebrafish NLRs with orthologs in tetrapods, and analysis of their tissue-specific expression. Results. Three distinct NLR subfamilies were identified by mining genome databases of various non-mammalian vertebrates; the first subfamily (NLR-A) resembles mammalian NODs, the second (NLR-B) resembles mammalian NALPs, while the third (NLR-C) appears to be unique to teleost fish. In zebrafish, NLR-A and NLR-B subfamilies contain five and six genes respectively. The third subfamily is large, containing several hundred NLR-C genes, many of which are predicted to encode a C-terminal B30.2 domain. This subfamily most likely evolved from a NOD3-like molecule. Gene predictions for zebrafish NLRs were verified using sequence derived from ESTs or direct sequencing of cDNA. Reverse-transcriptase (RT)-PCR analysis confirmed expression of representative genes from each subfamily in selected tissues. Conclusion. Our findings confirm the presence of multiple NLR gene orthologs, which form a large multigene family in teleostei. Although the functional significance of the three major NLR subfamilies is unclear, we speculate that conservation and abundance of NLR molecules in all teleostei genomes, reflects an essential role in cellular control, apoptosis or immunity throughout bony fish. ?? 2008 Laing et al; licensee BioMed Central Ltd.

  16. Diet and trophic level of the longnose spurdog Squalus blainville (Risso, 1826) in the deep waters of the Aegean Sea

    NASA Astrophysics Data System (ADS)

    Kousteni, Vasiliki; Karachle, Paraskevi K.; Megalofonou, Persefoni

    2017-06-01

    Knowledge of the diet and trophic level of marine predators is essential to develop an understanding of their ecological role in ecosystems. Research conducted on the trophic ecology of the deep-sea sharks is rather limited. The purpose of this study was to examine the diet of the longnose spurdog Squalus blainville, a deep-sea shark categorized as "data deficient" within its distribution range, with respect to sex, maturity, age, season and sampling location. The stomach contents of 211 specimens, captured in the Aegean (off Skyros and the Cyclades Islands) and Cretan Seas, using commercial bottom-trawlers from 2005 to 2012, were analysed. The cumulative prey curve showed that the sample size was adequate to describe the species' diet. The identified prey items belonged to five major groups: Teleostei, Crustacea, Cephalopoda, Annelida and Phanerogams. Higher diet diversity was observed in females compared to males, in immature individuals compared to mature ones, regardless of sex, and in spring and winter compared to other seasons. Age and sampling location seemed to influence both the diet diversity and trophic spectrum of the species. Feeding intensity based on the vacuity index was not significantly influenced by any of the factors examined, while the stomach filling degree was significantly influenced by all factors, except sex, showing significantly higher values in mature females compared to immature ones, in older individuals, in autumn compared to winter, and a significantly lower value in the Cyclades Islands compared to other locations. Females showed a significant larger mouth length compared to males of the same length, while no between-sex differences were found in gut morphometrics. The estimated fractional trophic level (TROPH=4.41) classified the species as carnivore with a preference for Teleostei and Cephalopoda, confirming its high trophic position.

  17. Consistency of individual differences in behaviour of the lion-headed cichlid, Steatocranus casuarius.

    PubMed

    Budaev, S V; Zworykin, D D; Mochek, A D

    1999-11-01

    The development of individual differences in behaviour in a novel environment, in the presence of a strange fish and during aggressive interactions with a mirror-image was studied in the lion-headed cichlid (Steatocranus casuarius, Teleostei, Cichlidae). No consistency in behaviour was found at 4-5.5 months of age. However, behaviours scored in situations involving a discrete source of stress (a strange fish or conspecific) become significantly consistent at the age of 12 months. At 4-5.5 but not 12 months of age, larger individuals approached and attacked the strange fish significantly more than smaller ones. These patterns may be associated with development and integration of motivational systems and alternative coping strategies.

  18. Descriptions of fishes from the cretaceous and tertiary deposits west of the Mississippi River

    USGS Publications Warehouse

    Cope, E.D.

    1878-01-01

    This, with the genus following, introduces for the first time into the North American extinct fauna the family of the Dercetiform fishes. The relationship of the family has been discussed by various authors, especially by Pictet and Von der Marek. The former regards them as Teleostei; the latter as "Ganoids". As I do not adopt the division signified by the last name, I find Professor Pictet's view nearer to the point. The specimens indicate further that the Dercetidae belong to the Actinopteri, and probably to the order Hemibranchii. The only alternative is the order Isospondyli, and the characters which separate the two are not clearly shown in the specimens. Distinct bones below the pectoral fins may be interclavicles, which belong to the Hemibranchii.

  19. Developmental transcriptome analysis and identification of genes involved in formation of intestinal air-breathing function of Dojo loach, Misgurnus anguillicaudatus

    PubMed Central

    Luo, Weiwei; Cao, Xiaojuan; Xu, Xiuwen; Huang, Songqian; Liu, Chuanshu; Tomljanovic, Tea

    2016-01-01

    Dojo loach, Misgurnus anguillicaudatus is a freshwater fish species of the loach family Cobitidae, using its posterior intestine as an accessory air-breathing organ. Little is known about the molecular regulatory mechanisms in the formation of intestinal air-breathing function of M. anguillicaudatus. Here high-throughput sequencing of mRNAs was performed from six developmental stages of posterior intestine of M. anguillicaudatus: 4-Dph (days post hatch) group, 8-Dph group, 12-Dph group, 20-Dph group, 40-Dph group and Oyd (one-year-old) group. These six libraries were assembled into 81300 unigenes. Totally 40757 unigenes were annotated. Subsequently, 35291 differentially expressed genes (DEGs) were scanned among different developmental stages and clustered into 20 gene expression profiles. Finally, 15 key pathways and 25 key genes were mined, providing potential targets for candidate gene selection involved in formation of intestinal air-breathing function in M. anguillicaudatus. This is the first report of developmental transcriptome of posterior intestine in M. anguillicaudatus, offering a substantial contribution to the sequence resources for this species and providing a deep insight into the formation mechanism of its intestinal air-breathing function. This report demonstrates that M. anguillicaudatus is a good model for studies to identify and characterize the molecular basis of accessory air-breathing organ development in fish. PMID:27545457

  20. The post-larval and juvenile fish assemblage in the Sukhothai floodplain, Thailand

    NASA Astrophysics Data System (ADS)

    Siriwan, Suksri; Boonsatien, Boonsoong

    2017-06-01

    This study investigated abundance, species composition and spatial and temporal distributions of fish larvae and their relationship with some environmental variables in the Sukhothai floodplain in northern Thailand. Fish larvae were collected from 33 sampling stations on 8 occasions between August 2010 and October 2013. The study collected and identified 149 296 individuals, representing 32 families and 165 taxa. The species composition of larval fish was dominated by the Cyprinidae (47.27%), Cobitidae (7.88%), Siluridae (6.67%), Bagridae (6.06%) and Mastacembelidae (3.33%) families. The most-abundant larval species were the Striped flying barb Esomus metallicus (16.90%), the Siamese mud carp Henicorhynchus siamensis (8.48%) and the Sumatran river sprat Clupeichthys goniognathus (8.31%). The greatest abundance and species diversity of larvae were found when the river flow runs onto the floodplain. PCA and nMDS analysis revealed that the samples plot is associated with temporal distribution among years. The discharge was a major factor determining fish larvae assemblage and environmental variables in the Sukhothai floodplain. Four fish larval species were positively correlated with the samples for 2013. The result of the CCA ordination plot showed that only the discharge variable was strongly correlated with fish larvae abundance, especially two cyprinid Rasbora species.

  1. Rapid diversification of FoxP2 in teleosts through gene duplication in the teleost-specific whole genome duplication event.

    PubMed

    Song, Xiaowei; Wang, Yajun; Tang, Yezhong

    2013-01-01

    As one of the most conserved genes in vertebrates, FoxP2 is widely involved in a number of important physiological and developmental processes. We systematically studied the evolutionary history and functional adaptations of FoxP2 in teleosts. The duplicated FoxP2 genes (FoxP2a and FoxP2b), which were identified in teleosts using synteny and paralogon analysis on genome databases of eight organisms, were probably generated in the teleost-specific whole genome duplication event. A credible classification with FoxP2, FoxP2a and FoxP2b in phylogenetic reconstructions confirmed the teleost-specific FoxP2 duplication. The unavailability of FoxP2b in Danio rerio suggests that the gene was deleted through nonfunctionalization of the redundant copy after the Otocephala-Euteleostei split. Heterogeneity in evolutionary rates among clusters consisting of FoxP2 in Sarcopterygii (Cluster 1), FoxP2a in Teleostei (Cluster 2) and FoxP2b in Teleostei (Cluster 3), particularly between Clusters 2 and 3, reveals asymmetric functional divergence after the gene duplication. Hierarchical cluster analyses of hydrophobicity profiles demonstrated significant structural divergence among the three clusters with verification of subsequent stepwise discriminant analysis, in which FoxP2 of Leucoraja erinacea and Lepisosteus oculatus were classified into Cluster 1, whereas FoxP2b of Salmo salar was grouped into Cluster 2 rather than Cluster 3. The simulated thermodynamic stability variations of the forkhead box domain (monomer and homodimer) showed remarkable divergence in FoxP2, FoxP2a and FoxP2b clusters. Relaxed purifying selection and positive Darwinian selection probably were complementary driving forces for the accelerated evolution of FoxP2 in ray-finned fishes, especially for the adaptive evolution of FoxP2a and FoxP2b in teleosts subsequent to the teleost-specific gene duplication.

  2. Rapid Diversification of FoxP2 in Teleosts through Gene Duplication in the Teleost-Specific Whole Genome Duplication Event

    PubMed Central

    Song, Xiaowei; Wang, Yajun; Tang, Yezhong

    2013-01-01

    As one of the most conserved genes in vertebrates, FoxP2 is widely involved in a number of important physiological and developmental processes. We systematically studied the evolutionary history and functional adaptations of FoxP2 in teleosts. The duplicated FoxP2 genes (FoxP2a and FoxP2b), which were identified in teleosts using synteny and paralogon analysis on genome databases of eight organisms, were probably generated in the teleost-specific whole genome duplication event. A credible classification with FoxP2, FoxP2a and FoxP2b in phylogenetic reconstructions confirmed the teleost-specific FoxP2 duplication. The unavailability of FoxP2b in Danio rerio suggests that the gene was deleted through nonfunctionalization of the redundant copy after the Otocephala-Euteleostei split. Heterogeneity in evolutionary rates among clusters consisting of FoxP2 in Sarcopterygii (Cluster 1), FoxP2a in Teleostei (Cluster 2) and FoxP2b in Teleostei (Cluster 3), particularly between Clusters 2 and 3, reveals asymmetric functional divergence after the gene duplication. Hierarchical cluster analyses of hydrophobicity profiles demonstrated significant structural divergence among the three clusters with verification of subsequent stepwise discriminant analysis, in which FoxP2 of Leucoraja erinacea and Lepisosteus oculatus were classified into Cluster 1, whereas FoxP2b of Salmo salar was grouped into Cluster 2 rather than Cluster 3. The simulated thermodynamic stability variations of the forkhead box domain (monomer and homodimer) showed remarkable divergence in FoxP2, FoxP2a and FoxP2b clusters. Relaxed purifying selection and positive Darwinian selection probably were complementary driving forces for the accelerated evolution of FoxP2 in ray-finned fishes, especially for the adaptive evolution of FoxP2a and FoxP2b in teleosts subsequent to the teleost-specific gene duplication. PMID:24349554

  3. Synthesis of clonality and polyploidy in vertebrate animals by hybridization between two sexual species.

    PubMed

    Choleva, Lukáš; Janko, Karel; De Gelas, Koen; Bohlen, Jörg; Šlechtová, Věra; Rábová, Marie; Ráb, Petr

    2012-07-01

    Because most clonal vertebrates have hybrid genomic constitutions, tight linkages are assumed among hybridization, clonality, and polyploidy. However, predictions about how these processes mechanistically relate during the switch from sexual to clonal reproduction have not been validated. Therefore, we performed a crossing experiment to test the hypothesis that interspecific hybridization per se initiated clonal diploid and triploid spined loaches (Cobitis) and their gynogenetic reproduction. We reared two F1 families resulting from the crossing of 14 pairs of two sexual species, and found their diploid hybrid constitution and a 1:1 sex ratio. While males were infertile, females produced unreduced nonrecombinant eggs (100%). Synthetic triploid females and males (96.3%) resulted in each of nine backcrossed families from eggs of synthesized diploid F1s fertilized by haploid sperm from sexual males. Five individuals (3.7%) from one backcross family were genetically identical to the somatic cells of the mother and originated via gynogenesis; the sperm of the sexual male only triggered clonal development of the egg. Our reconstruction of the evolutionary route from sexuality to clonality and polyploidy in these fish shows that clonality and gynogenesis may have been directly triggered by interspecific hybridization and that polyploidy is a consequence, not a cause, of clonality. © 2012 The Author(s).

  4. Mechanosensation in an adipose fin

    PubMed Central

    2016-01-01

    Adipose fins are found on approximately 20% of ray-finned fish species. The apparently rudimentary anatomy of adipose fins inspired a longstanding hypothesis that these fins are vestigial and lack function. However, adipose fins have evolved repeatedly within Teleostei, suggesting adaptive function. Recently, adipose fins were proposed to function as mechanosensors, detecting fluid flow anterior to the caudal fin. Here we test the hypothesis that adipose fins are mechanosensitive in the catfish Corydoras aeneus. Neural activity, recorded from nerves that innervate the fin, was shown to encode information on both movement and position of the fin membrane, including the magnitude of fin membrane displacement. Thus, the adipose fin of C. aeneus is mechanosensitive and has the capacity to function as a ‘precaudal flow sensor’. These data force re-evaluation of adipose fin clipping, a common strategy for tagging fishes, and inform hypotheses of how function evolves in novel vertebrate appendages. PMID:26984621

  5. Mechanosensation in an adipose fin.

    PubMed

    Aiello, Brett R; Stewart, Thomas A; Hale, Melina E

    2016-03-16

    Adipose fins are found on approximately 20% of ray-finned fish species. The apparently rudimentary anatomy of adipose fins inspired a longstanding hypothesis that these fins are vestigial and lack function. However, adipose fins have evolved repeatedly within Teleostei, suggesting adaptive function. Recently, adipose fins were proposed to function as mechanosensors, detecting fluid flow anterior to the caudal fin. Here we test the hypothesis that adipose fins are mechanosensitive in the catfish Corydoras aeneus. Neural activity, recorded from nerves that innervate the fin, was shown to encode information on both movement and position of the fin membrane, including the magnitude of fin membrane displacement. Thus, the adipose fin of C. aeneus is mechanosensitive and has the capacity to function as a 'precaudal flow sensor'. These data force re-evaluation of adipose fin clipping, a common strategy for tagging fishes, and inform hypotheses of how function evolves in novel vertebrate appendages. © 2016 The Author(s).

  6. Mechanistic basis of otolith formation during teleost inner ear development

    PubMed Central

    Wu, David; Freund, Jonathan B.; Fraser, Scott E.; Vermot, Julien

    2011-01-01

    Otoliths, which are connected to stereociliary bundles in the inner ear, serve as inertial sensors for balance. In teleostei, otolith development is critically dependant on flow forces generated by beating cilia; however, the mechanism by which flow controls otolith formation remains unclear. Here, we have developed a non-invasive flow probe using optical tweezers and a viscous flow model in order to demonstrate how the observed hydrodynamics influence otolith assembly. We show that rotational flow stirs and suppresses precursor agglomeration in the core of the cilia-driven vortex. The velocity field correlates with the shape of the otolith and we provide evidence that hydrodynamics is actively involved in controlling otolith morphogenesis. An implication of this hydrodynamic effect is that otolith self-assembly is mediated by the balance between Brownian motion and cilia-driven flow. More generally, this flow feature highlights an alternative biological strategy for controlling particle localization in solution. PMID:21316594

  7. Seasonal variation in drifting eggs and larvae in the upper Yangtze, China.

    PubMed

    Jiang, Wei; Liu, Huan-Zhang; Duan, Zhong-Hua; Cao, Wen-Xuan

    2010-05-01

    From 5 March to 25 July 2008, ichthyoplankton drifting into the Three Gorges Reservoir from the upper reaches of the Yangtze River were sampled daily to investigate the species composition, abundance, and seasonal variation in early-stage fishes in this area. Twenty-eight species belonging to five orders and 17 families or subfamilies were identified by analyzing fish eggs and larvae, and a total of 14.16 billion individuals were estimated drifting through the sampling section during the investigation. Among the ichthyoplankton sampled, species in Cultrinae, Cobitidae, Gobioninae and Gobiidae, along with the common carp (Cyprinus carpio Linnaeus), comprised 89.6% of the total amount. Six peaks of drift density were identified during the sampling period, and a significant correlation was found between drift density with water discharge. The dominant species were different in each drift peak, indicating different spawning times for the major species. The total amount of the four major Chinese carps that drifted through the sampling section was estimated as 0.88 billion, indicating an increase in the population sizes of these species in the upper reaches of the Yangtze River after construction of the Three Gorges Dam. Actually, these reaches have become the largest spawning area for the four major Chinese carps in the Yangtze River. The large total amount of eggs and larvae drifting through this section demonstrated that the upper reaches of the Yangtze River provided important spawning sites for many fish species, and that conservation of this area should be of great concern.

  8. Five newly recorded Cyprinid fish (Teleostei: Cypriniformes) in Myanmar

    PubMed Central

    Qin, Tao; Chen, Zhi-Ying; Xu, Lu-Lu; Zaw, Paing; Kyaw, Yunn Mi Mi; Maung, Kyaw Win; Chen, Xiao-Yong

    2017-01-01

    Freshwater fish from the Putao and Myitkyina areas were collected in three ichthyofaunal surveys of the Mali Hka River and tributaries in and around Khakaborazi National Park and Hponkanrazi Wildlife Sanctuary, Kachin State, from 2014-2016. Tor yingjiangensis Chen et Yang 2004, Tor qiaojiensis Wu et al. 1977, Garra qiaojiensis Wu et al. 1977, Garra bispinosa Zhang 2005, and Schizothorax oligolepis Huang 1985, originally described from the upper Irrawaddy (Ayeyarwaddy) River in China, are first reported herein as new records to Myanmar. Counts, measurements, descriptions, photographs, and distributions of the specimens of the five newly recorded species are provided. PMID:29181904

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

    PubMed

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

    2015-04-01

    The growth and mortality rates of Myctophum affine larvae were analysed based on samples collected during the austral summer and winter of 2002 from south-eastern Brazilian waters. The larvae ranged in size from 2·75 to 14·00 mm standard length (L(S)). Daily increment counts from 82 sagittal otoliths showed that the age of M. affine ranged from 2 to 28 days. Three models were applied to estimate the growth rate: linear regression, exponential model and Laird-Gompertz model. The exponential model best fitted the data, and L(0) values from exponential and Laird-Gompertz models were close to the smallest larva reported in the literature (c. 2·5 mm L(S)). The average growth rate (0·33 mm day(-1)) was intermediate among lanternfishes. The mortality rate (12%) during the larval period was below average compared with other marine fish species but similar to some epipelagic fishes that occur in the area. © 2015 The Fisheries Society of the British Isles.

  10. Five newly recorded Cyprinid fish (Teleostei: Cypriniformes) in Myanmar.

    PubMed

    Qin, Tao; Chen, Zhi-Ying; Xu, Lu-Lu; Zaw, Paing; Mi Mi Kyaw, Yunn; Win Maung, Kyaw; Chen, Xiao-Yong

    2017-09-18

    Freshwater fish from the Putao and Myitkyina areas were collected in three ichthyofaunal surveys of the Mali Hka River and tributaries in and around Khakaborazi National Park and Hponkanrazi Wildlife Sanctuary, Kachin State, from 2014-2016. Tor yingjiangensis Chen et Yang 2004, Tor qiaojiensis Wu et al. 1977, Garra qiaojiensis Wu et al. 1977, Garra bispinosa Zhang 2005, and Schizothorax oligolepis Huang 1985, originally described from the upper Irrawaddy (Ayeyarwaddy) River in China, are first reported herein as new records to Myanmar. Counts, measurements, descriptions, photographs, and distributions of the specimens of the five newly recorded species are provided.

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

    PubMed Central

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

    2016-01-01

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

  12. The complete mitochondrial genome of Percocypris pingi (Teleostei, Cypriniformes).

    PubMed

    Li, Yanping; Wang, Jinjin; Peng, Zuogang

    2013-02-01

    Percocypris pingi is an endemic and economic fish species only found in the upper Yangtze River basin in China. It has become endangered in recent years due to overfishing and/or dam construction. However, the available genetic data are still scarce for this species. Here, we sequenced the complete mitochondrial genome sequence of P. pingi using long polymerase chain reactions. The complete mitogenome sequence has 16,586 bp and contains the usual 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA (tRNA) genes, and 1 control region, the gene composition and order of which are similar to most of other vertebrates. Most mitochondrial genes except ND6 and eight tRNAs are encoded on the heavy strand. The overall base composition of the heavy strand is 30.9% A, 25.7% T, 26.6% C, and 16.8% G with a slight AT bias of 56.6%. There are seven regions of gene overlaps totaling 23 bp and 11 intergenic spacer regions totaling 35 bp. Combined with the COI barcoding region sequences of other 25 cyprinids, the phylogenetic position of P. pingi was estimated using neighbor-joining method. The results showed that P. pingi had a close phylogenetic relationship with the species from genus Schizothorax. This mitogenome sequence data of P. pingi would provide the fundamental genetic data for further conservation genetic studies for this endangered fish species.

  13. Evolution of the locomotory system in eels (Teleostei: Elopomorpha).

    PubMed

    Pfaff, Cathrin; Zorzin, Roberto; Kriwet, Jürgen

    2016-08-11

    Living anguilliform eels represent a distinct clade of elongated teleostean fishes inhabiting a wide range of habitats. Locomotion of these fishes is highly influenced by the elongated body shape, the anatomy of the vertebral column, and the corresponding soft tissues represented by the musculotendinous system. Up to now, the evolution of axial elongation in eels has been inferred from living taxa only, whereas the reconstruction of evolutionary patterns and functional ecology in extinct eels still is scarce. Rare but excellently preserved fossil eels from the Late Cretaceous and Cenozoic were investigated here to gain a better understanding of locomotory system evolution in anguilliforms and, consequently, their habitat occupations in deep time. The number of vertebrae in correlation with the body length separates extinct and extant anguilliforms. Even if the phylogenetic signal cannot entirely be excluded, the analyses performed here reveal a continuous shortening of the vertebral column with a simultaneous increase in vertebral numbers in conjunction with short lateral tendons throughout the order. These anatomical changes contradict previous hypotheses based on extant eels solely. The body curvatures of extant anguilliforms are highly flexible and can be clearly distinguished from extinct species. Anatomical changes of the vertebral column and musculotendinous system through time and between extinct and extant anguilliforms correlate with changes of the body plan and swimming performance and reveal significant shifts in habitat adaptation and thus behaviour. Evolutionary changes in the skeletal system of eels established here also imply that environmental shifts were triggered by abiotic rather than biotic factors (e.g., K/P boundary mass extinction event).

  14. Mitochondrial diversity and phylogeography of Acrossocheilus paradoxus (Teleostei: Cyprinidae).

    PubMed

    Ju, Yu-Min; Hsu, Kui-Ching; Yang, Jin-Quan; Wu, Jui-Hsien; Li, Shan; Wang, Wei-Kuang; Ding, Fang; Li, Jun; Lin, Hung-Du

    2018-01-31

    Mitochondrial DNA cytochrome b sequences (1141 bp) in 229 specimens of Acrossocheilus paradoxus from 26 populations were identified as four lineages. The pairwise genetic distances among these four lineages ranged from 1.57 to 2.37% (mean= 2.00%). Statistical dispersal-vicariance analysis suggests that the ancestral populations were distributed over mainland China and Northern and Western Taiwan. Approximate Bayesian computation approaches show that the three lineages in Taiwan originated from the lineage in mainland China through three colonization routes during two glaciations. The results indicated that during the glaciation and inter-glacial periods, the Taiwan Strait was exposed and sank, which contributed to the dispersion and differentiation of populations. Furthermore, the populations of A. paradoxus colonized Taiwan through a land bridge to the north of the Formosa Bank, and the Miaoli Plateau in Taiwan was an important barrier that limited gene exchange between populations on both the sides.

  15. MicroRNA in Teleost Fish

    PubMed Central

    Bizuayehu, Teshome Tilahun; Babiak, Igor

    2014-01-01

    MicroRNAs (miRNAs) are transcriptional and posttranscriptional regulators involved in nearly all known biological processes in distant eukaryotic clades. Their discovery and functional characterization have broadened our understanding of biological regulatory mechanisms in animals and plants. They show both evolutionary conserved and unique features across Metazoa. Here, we present the current status of the knowledge about the role of miRNA in development, growth, and physiology of teleost fishes, in comparison to other vertebrates. Infraclass Teleostei is the most abundant group among vertebrate lineage. Fish are an important component of aquatic ecosystems and human life, being the prolific source of animal proteins worldwide and a vertebrate model for biomedical research. We review miRNA biogenesis, regulation, modifications, and mechanisms of action. Specific sections are devoted to the role of miRNA in teleost development, organogenesis, tissue differentiation, growth, regeneration, reproduction, endocrine system, and responses to environmental stimuli. Each section discusses gaps in the current knowledge and pinpoints the future directions of research on miRNA in teleosts. PMID:25053657

  16. Why the short face? Developmental disintegration of the neurocranium drives convergent evolution in neotropical electric fishes.

    PubMed

    Evans, Kory M; Waltz, Brandon; Tagliacollo, Victor; Chakrabarty, Prosanta; Albert, James S

    2017-03-01

    Convergent evolution is widely viewed as strong evidence for the influence of natural selection on the origin of phenotypic design. However, the emerging evo-devo synthesis has highlighted other processes that may bias and direct phenotypic evolution in the presence of environmental and genetic variation. Developmental biases on the production of phenotypic variation may channel the evolution of convergent forms by limiting the range of phenotypes produced during ontogeny. Here, we study the evolution and convergence of brachycephalic and dolichocephalic skull shapes among 133 species of Neotropical electric fishes (Gymnotiformes: Teleostei) and identify potential developmental biases on phenotypic evolution. We plot the ontogenetic trajectories of neurocranial phenotypes in 17 species and document developmental modularity between the face and braincase regions of the skull. We recover a significant relationship between developmental covariation and relative skull length and a significant relationship between developmental covariation and ontogenetic disparity. We demonstrate that modularity and integration bias the production of phenotypes along the brachycephalic and dolichocephalic skull axis and contribute to multiple, independent evolutionary transformations to highly brachycephalic and dolichocephalic skull morphologies.

  17. Reproductive biology of the Panama graysby Cephalopholis panamensis (Teleostei: Epinephelidae).

    PubMed

    Erisman, B E; Craig, M T; Hastings, P A

    2010-04-01

    The reproductive biology of the Panama graysby Cephalopholis panamensis was studied from collections and behavioural observations made in the Gulf of California from 2001 to 2006. Histological examinations, particularly the identification of gonads undergoing sexual transition, confirmed a protogynous hermaphroditic sexual pattern. The population structure and mating behaviour provided further support for protogyny. Size and age distributions by sex were bimodal, with males larger and older than females and sex ratios biased towards females. Mating groups consisted of a large male and several smaller females, and courtship occurred in pairs during the evening. Results on spawning periodicity and seasonality were incomplete, but histological data, monthly gonado-somatic indices (I(G)) and behavioural observations suggest that adults spawned around the full moon from May to September. Certain aspects of their reproductive biology (e.g. protogyny and low egg production) indicate that C. panamensis is particularly vulnerable to fishing and would benefit from a management policy in Mexico.

  18. Cryopreservation of spermatozoa of black marlin, Makaira indica (Teleostei: Istiophoridae).

    PubMed

    van der Straten, K M; Leung, L K-P; Rossini, R; Johnston, S D

    2006-01-01

    As a first step towards the development of a method for the cryopreservation of black marlin spermatozoa, this study investigated the effect of dimethylsulfoxide (DMSO) concentration and pellet size on post-thaw spermatozoal motility. Spermatozoa were recovered from the spermatic duct of testes retrieved post-mortem from four adult black marlin caught in the Coral Sea spawning grounds of Australia. Undiluted spermatozoa were stored on ice for 4 to 10 hours during transport to shore, then evaluated for motility after activation in seawater (1:10 v:v). Spermatozoa were prepared for cryopreservation in pellets by extension (1:3 v:v) in a defined fish Ringer's solution to give two final DMSO concentrations of 2.5% or 5.0%. Diluted spermatozoa were frozen directly on a dry ice block in pellet sizes of either 0.25 ml or 0.50 ml. Frozen pellets were thawed in a water bath at 40 degrees C for 60 seconds and assessed for post-thaw motility following activation in seawater. Spermatozoa recovered within 50 minutes of death and chilled on ice for 4 to 10 hours showed a mean (+/- SEM) motility immediately following activation of 91.6 +/- 7.9%. 50% of the spermatozoa remained motile for approximately 4 to 5 minutes. Following cryopreservation, mean motility declined significantly across all cryoprotectant and pellet size combinations (P < 0.001) but spermatozoa frozen in 2.5% DMSO showed higher motility than those frozen in 5.0% DMSO (P = 0.014). Pellet size had no effect on post-thaw motility (P = 0.179).

  19. Molecular cytogenetic of the Amoy croaker, Argyrosomus amoyensis (Teleostei, Sciaenidae)

    NASA Astrophysics Data System (ADS)

    Liao, Mengxiang; Zheng, Jiao; Wang, Zhiyong; Wang, Yilei; Zhang, Jing; Cai, Mingyi

    2017-08-01

    The family Sciaenidae is remarkable for its species richness and economic importance. However, the cytogenetic data available in this fish group are still limited, especially those obtained using fluorescence in situ hybridization (FISH). In the present study, the chromosome characteristics of a sciaenid species, Argyrosomus amoyensis, were examined with several cytogenetic methods, including dual-FISH with 18S and 5S rDNA probes, and a self-genomic in situ hybridization procedure (Self-GISH). The karyotype of A. amoyensis comprised 2n=48 acrocentric chromosomes. A single pair of nucleolar organizer regions (NORs) was located at the proximal position of chromosome 1, which was positive for silver nitrate impregnation (AgNO3) staining and denaturation-propidium iodide (DPI) staining but negative for Giemsa staining and 4',6-diamidino-2-phenylindole (DAPI) staining, and was confirmed by FISH with 18S rDNA probes. The 5S rDNA sites were located at the centromeric region of chromosome 3. Telomeric FISH signals were detected at all chromosome ends with different intensities, but internal telomeric sequences (ITSs) were not found. Self-GISH resulted in strong signals distributed at the centromeric regions of all chromosomes. C-banding revealed not only centromeric heterochromatin, but also heterochromatin that located on NORs, in interstitial and distal telomeric regions of specific chromosomes. These results suggest that the karyotype of Amoy croaker was relatively conserved and primitive. By comparison with the reported cytogenetic data of other sciaenids, it can be deduced that although the karyotypic macrostructure and chromosomal localization of 18S rDNA are conserved, the distribution of 5S rDNA varies dynamically among sciaenid species. Thus, the 5S rDNA sites may have different evolutionary dynamics in relation to other chromosomal regions, and have the potential to be effective cytotaxonomic markers in Sciaenidae.

  20. 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.

  1. 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.

  2. 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. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  3. Influence of cladogenesis on feeding structures in drums (Teleostei: Sciaenidae).

    PubMed

    Deary, Alison L; Hilton, Eric J

    2017-02-01

    Drums (family Sciaenidae) are common in tropical to temperate coastal and estuarine habitats worldwide and present a broad spectrum of morphological diversity. The anatomical variation in this family is particularly evident in their feeding apparatus, which may reflect the partitioning of adult foraging habitats. Adult and early life history stage sciaenids may display ecomorphological patterns in oral and pharyngeal jaw elements but because sciaenids are hierarchically related, the morphological variation of the feeding apparatus cannot be analyzed as independent data. Morphological patterns have been identified in three sciaenid genera from the Chesapeake Bay but it is not known if these patterns are present in other genera of the family and if such patterns are constrained by phylogenetic history. In this study, phylogenetic comparative methods were applied to two sets of oral jaw data obtained from growth series of 11 species of cleared and double-stained Chesapeake Bay sciaenids and alcohol-preserved museum specimens representing 65 of the 66 recognized genera to determine the magnitude of phylogenetic dependence present in the structure of the oral jaws using a recent molecular phylogeny of the family. Pagel's lambda, a measure of phylogenetic signal, was low for pelagic sciaenids in premaxilla, lower jaw, and ascending process lengths, indicating influence of selective forces on the condition of these traits. Conversely, for benthic sciaenids, phylogenetic signal was high for lower jaw and ascending process lengths, indicating significant phylogenetic constraint for their condition in these taxa. Pagel's lambda was intermediate for premaxilla length in benthic sciaenids, suggesting that the length of the premaxilla is influenced by a mix of selective forces and phylogenetic constraint. Although the ecomorphological patterns identified in the oral jaws of scaienids are not entirely free of phylogenetic dependence, selective forces related to foraging are likely driving the evolution of these structures. Copyright © 2016 Elsevier GmbH. All rights reserved.

  4. Horabagrus melanosoma: a junior synonym of Horabagrus brachysoma (Teleostei: Horabagridae).

    PubMed

    Ali, Anvar; Katwate, Unmesh; Philip, Siby; Dhaneesh, K V; Bijukumar, A; Raghavan, Rajeev; Dahanukar, Neelesh

    2014-11-06

    Horabagrus melanosoma was described from West Venpala in the lower reaches of the Manimala River, in the state of Kerala, India. It was distinguished from its nearest congener, H. brachysoma based on a combination of characters including darker body colour, shorter pelvic fin and greater number of anal fin rays. Examination of the type material revealed significant morphometric and meristic discrepancies with the original description. Based on multivariate morphometric, and genetic analysis of topotypical specimens, we propose that H. melanosoma should be treated as a junior synonym of H. brachysoma.

  5. The identity of Hamilton's Ticto Barb, Pethia ticto (Teleostei: Cyprinidae).

    PubMed

    Katwate, Unmesh; Raghavan, Rajeev; Dahanukar, Neelesh

    2015-06-04

    While describing the fishes of Ganges, Hamilton described Cyprinus ticto (now allocated to Pethia) from south-eastern parts of Bengal. The unavailability of type material and insufficient diagnostic characters in the original description resulted in ambiguities in the identity of this species. In this paper, we clarify the identity of P. ticto through an integrative-taxonomic approach. Pethia ticto can be distinguished from all other known species of the genus by a combination of characters that includes an abbreviated lateral line with 6-12 pored scales; 23-26 scales in lateral-scale row; 9 predorsal scales; ½4/1/3½-4 scales in transverse series; and a pigmentation pattern that includes a small black humeral spot covering the third and fourth lateral-line scales, a prominent spot on the caudal peduncle on the 16th-19th scales of the lateral-line scale row, and two rows of black spots scattered on the dorsal fin.

  6. New gadiform fishes (Teleostei, Gadiformes) from the Miocene of Algeria

    NASA Astrophysics Data System (ADS)

    Carnevale, Giorgio

    2007-02-01

    As part of the completion of studies on the Miocene fishes of the Chelif Basin (north-western Algeria), this paper represents a contribution to the knowledge of the Messinian gadiform diversity of this western Mediterranean, semi-enclosed, Neogene basin. A new genus and species of the family Macrouridae is erected ( Razelainia paradoxa n. gen. et sp.), two specimens are tentatively referred to already existing taxa ( Gadiculus cf. jonas; Merluccius cf. merluccius), and a species formerly assigned to the gadid genus Brosme is transferred to the genus Gaidropsarus ( Gaidropsarus murdjadjensis). The macrourid Razelainia paradoxa n. gen. et sp. is characterized by an unusual combination of: plesiomorphic gadiform features, such as low vertebral number (presumed), well-developed caudal-fin rays, presence of a single continuous dorsal fin originating just posterior to the neurocranium, anal-fin rays slightly longer than dorsal-fin rays; and derived, typically macrourid features, such as the presence of spinoid scales and the anterior anal-fin pterygiophores extending forward over the abdominal wall. A paleoecological analysis reveals that the Messinian gadiform assemblage of the Chelif Basin had a subtropical/warm temperate affinity, with a marked north-eastern Atlantic-Mediterranean biogeographic character.

  7. The oldest ionoscopiform from China sheds new light on the early evolution of halecomorph fishes

    PubMed Central

    Xu, Guang-Hui; Zhao, Li-Jun; Coates, Michael I.

    2014-01-01

    The Halecomorphi are a major subdivision of the ray-finned fishes. Although living halecomorphs are represented solely by the freshwater bowfin, Amia calva, this clade has a rich fossil history, and the resolution of interrelationships among extinct members is central to the problem of understanding the origin of the Teleostei, the largest clade of extant vertebrates. The Ionoscopiformes are extinct marine halecomorphs that were inferred to have originated in the Late Jurassic of Europe, and subsequently dispersed to the Early Cretaceous of the New World. Here, we report the discovery of a new ionoscopiform, Robustichthys luopingensis gen. et sp. nov., based on eight well-preserved specimens from the Anisian (242–247 Ma), Middle Triassic marine deposits of Luoping, eastern Yunnan Province, China. The new species documents the oldest known ionoscopiform, extending the stratigraphic range of this group by approximately 90 Ma, and the geographical distribution of this group into the Middle Triassic of South China, a part of eastern Palaeotethys Ocean. These new data provide a minimum estimate for the split of Ionoscopiformes from its sister clade Amiiformes and shed new light on the origin of ionoscopiform fishes. PMID:24872460

  8. Reduced sperm counts in guppies (Poecilia reticulata) following exposure to low levels of tributyltin and bisphenol A.

    PubMed Central

    Haubruge, E; Petit, F; Gage, M J

    2000-01-01

    There is increasing evidence that normal male reproductive function can be disrupted by exposure to pollutants in the environment that can exogenously mimic, antagonize or block sex-hormone function. One possible consequence of exposure to these xenobiotics is disruption to spermatogenesis, but results thus far provide only indirect and inconsistent evidence. In this study we exposed adult male guppies (Poeciliidae: Teleostei) to environmentally relevant levels of the common xenobiotics tributyltin (11.2-22.3 ngl-1) and bisphenol A (274-549 micrograms l-1) in experimental aquaria. After 21 days of exposure, we found significant declines (by 40-75%) in total sperm counts for male fishes exposed to tributyltin and bisphenol A compared with controls. This short-term decline in sperm count is unlikely to be the result of endocrine-mediated alteration of the germ line, and we found no change in testis size or sperm lengths between treatments. However, Sertoli cells, which facilitate the transport of maturing sperm into the testicular deferent duct (where they are stored prior to ejaculation), are directly sensitive to xenobiotic action and it is therefore possible that spermatogenesis was inhibited through in vivo interference with normal Sertoli-cell function. PMID:11413652

  9. Reduced sperm counts in guppies (Poecilia reticulata) following exposure to low levels of tributyltin and bisphenol A.

    PubMed

    Haubruge, E; Petit, F; Gage, M J

    2000-11-22

    There is increasing evidence that normal male reproductive function can be disrupted by exposure to pollutants in the environment that can exogenously mimic, antagonize or block sex-hormone function. One possible consequence of exposure to these xenobiotics is disruption to spermatogenesis, but results thus far provide only indirect and inconsistent evidence. In this study we exposed adult male guppies (Poeciliidae: Teleostei) to environmentally relevant levels of the common xenobiotics tributyltin (11.2-22.3 ngl-1) and bisphenol A (274-549 micrograms l-1) in experimental aquaria. After 21 days of exposure, we found significant declines (by 40-75%) in total sperm counts for male fishes exposed to tributyltin and bisphenol A compared with controls. This short-term decline in sperm count is unlikely to be the result of endocrine-mediated alteration of the germ line, and we found no change in testis size or sperm lengths between treatments. However, Sertoli cells, which facilitate the transport of maturing sperm into the testicular deferent duct (where they are stored prior to ejaculation), are directly sensitive to xenobiotic action and it is therefore possible that spermatogenesis was inhibited through in vivo interference with normal Sertoli-cell function.

  10. An ultracentrifugation analysis of two hundred fish genomes.

    PubMed

    Bucciarelli, Giuseppe; Bernardi, Giacomo; Bernardi, Giorgio

    2002-08-07

    The goal of this study was to provide a comprehensive view of the compositional characteristics of fish genomes. We therefore expanded the number of fish species that we had explored so far in their DNAs by analytical ultracentrifugation in CsCl density gradient from 122 to 201. This study included representatives from three out of nine orders of Elasmobranchs (sharks and rays), both orders of dipnoan lungfishes, and both orders of chondrosteans (sturgeons and bichirs). We also studied 19 out of 38 teleostean orders, which represent all but four (minor) superorders of the subdivision Teleostei, a group comprising about 23,600 species (96% of all extant fishes). This leaves for further studies two subclasses, Holocephali (chimaeras), and Coelacanthimorpha (gombessas). In spite of this substantial increase in the number of species and orders analysed, all average properties (the modal buoyant density, rho(0), the average buoyant density, , the CsCl profile asymmetry, A, and the compositional heterogeneity, H), and all their ranges were unchanged compared to a previous study [J. Mol. Evol. 31 (1990) 265]. This suggests that, in all likelihood, the properties reported in the present paper can be considered as generally valid for all fish genomes.

  11. Myxosporea (Cnidaria : Myxozoa) infecting the saddled seabream Oblada melanura (L. 1758) (Teleostei : Sparidae) and the painted comber Serranus scriba (L. 1758) (Teleostei : Serranidae) in Tunisia.

    PubMed

    Laamiri, Sayef

    2017-05-19

    First parasitological surveys of Myxozoa are performed on the sparid saddled seabream Oblada melanura (Linnaeus, 1758) and the serranid painted comber Serranus scriba (Linnaeus, 1758) caught from the Bay of Bizerte and the Gulf of Tunis respectively in Northeast Tunisia, Western Mediterranean. In this study, 6 bivalvulid myxosporean species belonging to the 3 genera Ceratomyxa Thélohan, 1892, Myxodavisia Zhao, Zhou, Kent & Whipps, 2008 and Zschokkella Auerbach, 1910, are isolated infecting their hosts. Two species Ceratomyxa sp. 1 ex O. melanura (Prevalence (P) = 36%) and Ceratomyxa sp. 2 ex O. melanura (P = 13%) infected the saddled seabream and four species Ceratomyxa sp. 1 ex S. scriba (P = 11.7%), Ceratomyxa sp. 2 ex S. scriba (P = 6.7%), Myxodavisia sp. (P = 8.3%) and Zschokkella sp. (P = 5.6%) infected the painted comber. These myxosporeans differ, in vegetative stages and/or in mature spores, from all the previously known congeneric species, and are described here on the basis of their morphological and morphometric features, their host and tissue specificities and their biogeographical distribution. This is the first report of myxosporean infections in O. melanura and S. scriba. The occurrence of two ceratomyxid species in each host species supports that the genus Ceratomyxa is host-specific not only in sparids but also in serranids, which agrees with data previously obtained from Sparidae in Mediterranean Sea and from Serranidae in GBR, Australia. A member of the myxosporean genus Myxodavisia is recorded from the Mediterranean Sea for the first time, and Zschokkella spp. infections have not previously been recorded from a host in Serranidae. During the examination, a several cases of Co-infection among myxosporeans, both with two and three species, are provided and statistically studied. Indeed, 5% of the breams and 9.4% of the combers are infected with more than one myxosporean parasite. The relationship between myxosporean infections and some biological parameters are pointed out. A higher prevalence of myxosporean infection is coincided with the peak period of spawning activity in May-June for S. scriba. For both hosts, analysis using Fulton's condition factor (K) has revealed no significant difference between infected and non-infected fishes. Clinically, no external signs of disease have been occurred in infected hosts, but some changes in the bile fluid, colour, and viscosity and in the gall bladder 's tissue are examined in S. scriba.

  12. Drinking induced by angiotensin II in fishes.

    PubMed

    Kobayashi, H; Uemura, H; Takei, Y; Itatsu, N; Ozawa, M; Ichinohe, K

    1983-02-01

    Among 20 species of freshwater fishes examined, Pseudorasbora parva, Rhodeus ocellatus, Cobitis anguillicaudatus, Carassius auratus, Oryzias latipes, Gambusia affinis, and Gyrinocheilus anymonieri were found to drink water like seawater fishes, while 13 remaining species did not drink. For fish species found exclusively in fresh water, angiotensin II (AII) treatment did not induce drinking. In contrast, those freshwater fishes which survive in estuarine brackish water (Leuciscus hakonensis, C. carassius, Parasilurus asotus, G. affinis, Chaenogobius annularis, Tridentiger obscurus, and G. anymonieri responded to AII by drinking. Furthermore, some freshwater fishes which survive either in hypertonic water (C. auratus) or in sea water (Anguilla japonica and O. latipes) also responded to AII by drinking. Of 17 seawater fishes examined, Eptatretus burgeri, Triakis scyllia, and Heterodontus japonicus failed to drink water, and for Trachurus japonicus, Platichthys bicoloratus, and Glossogobius giuris fasciatopunctatus, water intake was minor (similar to freshwater fishes). The 11 remaining seawater fishes drank water. AII did not induce drinking in fishes living exclusively in sea water. However, seawater fishes which survive either in tide pools (Chasmichthys dolichognathus gulosus) or in brackish water (Sillago japonica, Mugil cephalus, G. giuris fasciatopunctatus) responded to AII by drinking. P. bicoloratus, Acanthopagrus schlegeli, and Fugu niphobles were exceptional, in that they survive in brackish water, but did not respond to AII. Although some exceptions exist, it is generally concluded that a drinking response to AII is characteristic of fishes which encounter water more hypertonic than that in which they typically reside. Accordingly, a drinking mechanism induced by AII may be a compensatory emergency reaction to dehydration stress.

  13. 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

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

    PubMed

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

    2016-05-31

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

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

    PubMed

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

    2014-01-20

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

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

    PubMed

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

    2016-10-04

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

  17. 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. Copyright © 2013 Wiley Periodicals, Inc.

  18. Is sexual selection driving diversification of the bioluminescent ponyfishes (Teleostei: Leiognathidae)?

    PubMed

    Chakrabarty, Prosanta; Davis, Matthew P; Smith, W Leo; Baldwin, Zachary H; Sparks, John S

    2011-07-01

    Sexual selection may facilitate genetic isolation among populations and result in increased rates of diversification. As a mechanism driving diversification, sexual selection has been invoked and upheld in numerous empirical studies across disparate taxa, including birds, plants and spiders. In this study, we investigate the potential impact of sexual selection on the tempo and mode of ponyfish evolution. Ponyfishes (Leiognathidae) are bioluminescent marine fishes that exhibit sexually dimorphic features of their unique light-organ system (LOS). Although sexual selection is widely considered to be the driving force behind ponyfish speciation, this hypothesis has never been formally tested. Given that some leiognathid species have a sexually dimorphic LOS, whereas others do not, this family provides an excellent system within which to study the potential role of sexual selection in diversification and morphological differentiation. In this study, we estimate the phylogenetic relationships and divergence times for Leiognathidae, investigate the tempo and mode of ponyfish diversification, and explore morphological shape disparity among leiognathid clades. We recover strong support for a monophyletic Leiognathidae and estimate that all major ponyfish lineages evolved during the Paleogene. Our studies of ponyfish diversification demonstrate that there is no conclusive evidence that sexually dimorphic clades are significantly more species rich than nonsexually dimorphic lineages and that evidence is lacking to support any significant diversification rate increases within ponyfishes. Further, we detected a lineage-through-time signal indicating that ponyfishes have continuously diversified through time, which is in contrast to many recent diversification studies that identify lineage-through-time patterns that support mechanisms of density-dependent speciation. Additionally, there is no evidence of sexual selection hindering morphological diversity, as sexually dimorphic taxa are shown to be more disparate in overall shape morphology than nonsexually dimorphic taxa. Our results suggest that if sexual selection is occurring in ponyfish evolution, it is likely acting only as a genetic isolating mechanism that has allowed ponyfishes to continuously diversify over time, with no overall impact on increases in diversification rate or morphological disparity. © 2011 Blackwell Publishing Ltd.

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

    PubMed

    Silva, Rodet Rodriguez

    2015-04-24

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

  20. 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

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

    PubMed

    Sarabeev, Volodimir

    2015-08-01

    Quantitative complex analyses of parasite communities of invaders across different native and introduced populations are largely lacking. The present study provides a comparative analysis of species richness of helminth parasites in native and invasive populations of grey mullets. The local species richness differed between regions and host species, but did not differ when compared with invasive and native hosts. The size of parasite assemblages of endohelminths was higher in the Mediterranean and Azov-Black Seas, while monogeneans were the most diverse in the Sea of Japan. The helminth diversity was apparently higher in the introduced population of Liza haematocheilus than that in their native habitat, but this trend could not be confirmed when the size of geographic range and sampling efforts were controlled for. The parasite species richness at the infracommunity level of the invasive host population is significantly lower compared with that of the native host populations that lends support to the enemy release hypothesis. A distribution pattern of the infracommunity richness of acquired parasites by the invasive host can be characterized as aggregated and it is random in native host populations. Heterogeneity in the host susceptibility and vulnerability to acquired helminth species was assumed to be a reason of the aggregation of species numbers in the population of the invasive host. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

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

    PubMed Central

    Kostadinova, Aneta

    2008-01-01

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

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

    PubMed

    Kostadinova, Aneta

    2008-12-31

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

  4. Malagasy cichlids differentially limit impacts of body shape evolution on oral jaw functional morphology.

    PubMed

    Martinez, Christopher M; Sparks, John S

    2017-09-01

    Patterns of trait covariation, such as integration and modularity, are vital factors that influence the evolution of vertebrate body plans. In functional systems, decoupling of morphological modules buffers functional change in one trait by reducing correlated variation with another. However, for complex morphologies with many-to-one mapping of form to function (MTOM), resistance to functional change may also be achieved by constraining morphological variation within a functionally stable region of morphospace. For this research, we used geometric morphometrics to evaluate the evolution of body shape and its relationship with jaw functional morphology in two independent radiations of endemic Malagasy cichlid (Teleostei: Cichlidae). Our results suggested that the two subfamilies used different strategies to mitigate impacts of body shape variation on a metric of jaw function, maxillary kinematic transmission (MKT): (1) modularity between cranial and postcranial morphologies, and (2) integration of body and jaw evolution, with jaw morphologies varying in a manner that limits change in MKT. This research shows that, unlike modularity, MTOM allows traits to retain strong evolutionary covariation while still reducing impacts on functionality. These results suggest that MTOM, and its influence on the evolution of correlated traits, is likely much more widespread than is currently understood. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  5. Analysis of food habits of skate Rioraja agassizii (Elasmobranchii, Rajidae) from southern Brazil.

    PubMed

    Motta, N S; Della-Fina, N; Souza, C C A; Rodrigues, E S; Amorim, A F

    2016-06-01

    Catches and exports of skate Rioraja agassizii place this species as "vulnerable to extinction" on the IUCN Red List; therefore, biological and ecological knowledge becomes an important instrument for its conservation control. This study described and quantified the diet composition of R. agassizii by means of stomach analysis contents in the periods 2005-2006 and 2012-2013. We analyzed and quantified stomach contents in terms of abundance (%N), weight (%M), frequency of occurrence (% FO), and index of relative importance (IRI). The results showed differences in the food rates between the periods. However, the groups of food items were the same: Teleostei fish, decapods, and mollusks. In 2005-2006, the diet consisted mainly of shrimp, however, in 2012-2013 it consisted of fish, followed by decapods, especially shrimps. The differences in diets may be attributed to shrimp abundance, which do not characterize a change in the eating habits in 2012-2013, because, in addition to fish, shrimps were also important food sources. The presence of a certain prey is more related to its availability rather than the feeding preference of skate. The amount of ingested items is associated to biological and environmental factors, so that further studies relating diet with capture area, seasonality, depth, and other factors should be conducted.

  6. Purification and characterization of galanin and scyliorhinin I from the hybrid sturgeon, Scaphirhynchus platorynchus x Scaphirhynchus albus (Acipenseriformes).

    PubMed

    Wang, Y; Barton, B A; Thim, L; Nielsen, P F; Conlon, J M

    1999-01-01

    The sturgeons (order Acipenseriformes) are extant representatives of a group of ancient Actinopterygian (ray-finned) fish. Galanin and scyliorhinin I (a tachykinin with limited structural similarity to mammalian substance P) have been isolated from an extract of the gastrointestinal tract of a sturgeon (an F1 hybrid between the shovelnose sturgeon, Scaphirhynchus platorynchus, and the pallid sturgeon, Scaphirhynchus albus). The primary structure of sturgeon galanin (Gly-Trp-Thr-Leu-Asn-Ser-Ala-Gly-Tyr-Leu10-Leu-Gly-Pro-His-Ala-Val -As p-Gly-His-Arg20-Ser-Leu-Ser-Asp-Lys-His-Gly-Leu-Pro.NH2) contains only two amino acid substitutions (Ser23 --> Asn and Pro29 --> Ala) compared with galanin from the bowfin, Amia calva (Amiiformes), but five amino acid substitutions compared with galanin from the trout (Teleostei). Similarly, the sturgeon tachykinin (Ser-Lys-Tyr-His-Gln-Phe-Tyr-Gly-Leu-Met.NH2) contains only one amino acid substitution (Tyr3 --> Ser) compared with scyliorhinin I previously isolated from bowfin stomach but five amino acid substitutions compared with trout substance P. The data support the hypothesis that the Acipenseriformes and the basal Neopterygians (gars and bowfin) share a close phylogenetic relationship. Copyright 1999 Academic Press.

  7. The oldest ionoscopiform from China sheds new light on the early evolution of halecomorph fishes.

    PubMed

    Xu, Guang-Hui; Zhao, Li-Jun; Coates, Michael I

    2014-05-01

    The Halecomorphi are a major subdivision of the ray-finned fishes. Although living halecomorphs are represented solely by the freshwater bowfin, Amia calva, this clade has a rich fossil history, and the resolution of interrelationships among extinct members is central to the problem of understanding the origin of the Teleostei, the largest clade of extant vertebrates. The Ionoscopiformes are extinct marine halecomorphs that were inferred to have originated in the Late Jurassic of Europe, and subsequently dispersed to the Early Cretaceous of the New World. Here, we report the discovery of a new ionoscopiform, Robustichthys luopingensis gen. et sp. nov., based on eight well-preserved specimens from the Anisian (242-247 Ma), Middle Triassic marine deposits of Luoping, eastern Yunnan Province, China. The new species documents the oldest known ionoscopiform, extending the stratigraphic range of this group by approximately 90 Ma, and the geographical distribution of this group into the Middle Triassic of South China, a part of eastern Palaeotethys Ocean. These new data provide a minimum estimate for the split of Ionoscopiformes from its sister clade Amiiformes and shed new light on the origin of ionoscopiform fishes. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  8. A parvicapsulid (Myxozoa) infecting Sprattus sprattus and Clupea harengus (Clupeidae) in the Northeast Atlantic uses Hydroides norvegicus (Serpulidae) as invertebrate host.

    PubMed

    Køie, Marianne; Karlsbakk, Egil; Einen, Ann-Cathrine Bårdsgjtere; Nylund, Are

    2013-05-01

    A myxosporean producing actinospores of the tetractinomyxon type in Hydroides norvegicus Gunnerus (Serpulidae) in Denmark was identified as a member of the family Parvicapsulidae based on small-subunit ribosomal DNA (SSU rDNA) sequences. Myxosporean samples from various Danish and Norwegian marine fishes were examined with primers that detect the novel myxosporean. Sprattus sprattus (Linnaeus) and Clupea harengus Linnaeus (Teleostei, Clupeidae) were found to be infected. The sequences of this parvicapsulid from these hosts were consistently slightly different (0.8% divergence), but both these genotypes were found in H. norvegicus. Disporic trophozoites and minute spores of a novel myxosporean type were observed in the renal tubules of some of the hosts found infected through PCR. The spores appear most similar to those of species of Gadimyxa Køie, Karlsbakk et Nylund, 2007, but are much smaller. The actinospores of the tetractinomyxon type from H. norvegicus have been described previously. In GenBank, the SSU rDNA sequences of Parvicapsulidae gen. sp. show highest identity (82%) with Parvicapsula minibicornis Kent, Whitaker et Dawe, 1997 infecting salmonids (Oncorhynchus spp.) in fresh water in the western North America. A phylogenetic analysis places P. minibicornis and Parvicapsulidae gen. sp. in a sister clade to the other parvicapsulids (Parvicapsula spp. and Gadimyxa spp.).

  9. The effects of heavy metal mine drainage on population size structure, reproduction, and condition of western mosquitofish, Gambusia affinis.

    PubMed

    Franssen, Courtney M

    2009-07-01

    Anthropogenic degradation of aquatic environments worldwide results in disturbed habitats, altered communities, and stressed populations. Surface waters located in an abandoned lead-zinc mining district in northeastern Oklahoma are no exception. This study examines the reproductive and somatic responses of a pollution-tolerant fish, the western mosquitofish, Gambusia affinis (Teleostei: Poeciliidae), living in mine outflow waters contaminated by heavy metals. Populations were sampled from four streams, which were classified into three habitat types. Populations from Tar Creek and an Unnamed Tributary of Tar Creek receive direct input of mine drainage, while populations living in reference creeks are not known to have mining influence. The influence of mine drainage directly or indirectly (via altered competitor and predator regimes or changes in food availability) affects G. affinis at both the population and the individual level. Metal-contaminated sites had reduced proportions of males and reproductively active females and altered male population size structures. Individual-level effects were apparent, as all G. affinis from Tar Creek invested less in liver weights, and mature males and reproductively active females from Tar Creek invested less in gonad weights. Furthermore, males from impacted sites were significantly lighter than those from reference creeks. Gravid females from Tar Creek had smaller clutch sizes, but average embryo weight did not differ among streams.

  10. Molecular and functional characterization of a fads2 orthologue in the Amazonian teleost, Arapaima gigas.

    PubMed

    Lopes-Marques, Mónica; Ozório, Rodrigo; Amaral, Ricardo; Tocher, Douglas R; Monroig, Óscar; Castro, L Filipe C

    2017-01-01

    The Brazilian teleost Arapaima gigas is an iconic species of the Amazon. In recent years a significant effort has been put into the farming of arapaima to mitigate overfishing threats. However, little is known regarding the nutritional requirements of A. gigas in particular those for essential fatty acids including the long-chain polyunsaturated fatty acids (LC-PUFA) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The ability to biosynthesize LC-PUFA is dependent upon the gene repertoire of fatty acyl desaturases (Fads) and elongases (Elovl), as well as their fatty acid specificities. In the present study we characterized both molecularly and functionally an orthologue of the desaturase fatty acid desaturase 2 (fads2) from A. gigas. The isolated sequence displayed the typical desaturase features, a cytochrome b 5 -domain with the heme-binding motif, two transmembrane domains and three histidine-rich regions. Functional characterization of A. gigas fads2 showed that, similar to other teleosts, the A. gigas fads2 exhibited a predominant Δ6 activity complemented with some capacity for Δ8 desaturation. Given that A. gigas belongs to one of the oldest teleostei lineages, the Osteoglossomorpha, these findings offer a significant insight into the evolution LC-PUFA biosynthesis in teleosts. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. A fossil unicorn crestfish (Teleostei, Lampridiformes, Lophotidae) from the Eocene of Iran.

    PubMed

    Davesne, Donald

    2017-01-01

    Lophotidae, or crestfishes, is a family of rare deep-sea teleosts characterised by an enlarged horn-like crest on the forehead. They are poorly represented in the fossil record, by only three described taxa. One specimen attributed to Lophotidae has been described from the pelagic fauna of the middle-late Eocene Zagros Basin, Iran. Originally considered as a specimen of the fossil lophotid † Protolophotus , it is proposed hereby as a new genus and species † Babelichthys olneyi , gen. et sp. nov., differs from the other fossil lophotids by its relatively long and strongly projecting crest, suggesting a close relationship with the modern unicorn crestfish, Eumecichthys . This new taxon increases the diversity of the deep-sea teleost fauna to which it belongs, improving our understanding of the taxonomic composition of the early Cenozoic mesopelagic ecosystems.

  12. A Glimpse into the Satellite DNA Library in Characidae Fish (Teleostei, Characiformes)

    PubMed Central

    Utsunomia, Ricardo; Ruiz-Ruano, Francisco J.; Silva, Duílio M. Z. A.; Serrano, Érica A.; Rosa, Ivana F.; Scudeler, Patrícia E. S.; Hashimoto, Diogo T.; Oliveira, Claudio; Camacho, Juan Pedro M.; Foresti, Fausto

    2017-01-01

    Satellite DNA (satDNA) is an abundant fraction of repetitive DNA in eukaryotic genomes and plays an important role in genome organization and evolution. In general, satDNA sequences follow a concerted evolutionary pattern through the intragenomic homogenization of different repeat units. In addition, the satDNA library hypothesis predicts that related species share a series of satDNA variants descended from a common ancestor species, with differential amplification of different satDNA variants. The finding of a same satDNA family in species belonging to different genera within Characidae fish provided the opportunity to test both concerted evolution and library hypotheses. For this purpose, we analyzed here sequence variation and abundance of this satDNA family in ten species, by a combination of next generation sequencing (NGS), PCR and Sanger sequencing, and fluorescence in situ hybridization (FISH). We found extensive between-species variation for the number and size of pericentromeric FISH signals. At genomic level, the analysis of 1000s of DNA sequences obtained by Illumina sequencing and PCR amplification allowed defining 150 haplotypes which were linked in a common minimum spanning tree, where different patterns of concerted evolution were apparent. This also provided a glimpse into the satDNA library of this group of species. In consistency with the library hypothesis, different variants for this satDNA showed high differences in abundance between species, from highly abundant to simply relictual variants. PMID:28855916

  13. Crushing motor patterns in drum (Teleostei: Sciaenidae): functional novelties associated with molluscivory.

    PubMed

    Grubich, J R

    2000-10-01

    This study explores the evolution of molluscivory in the marine teleost family Sciaenidae by comparing the motor activity patterns of the pharyngeal muscles of two closely related taxa, the molluscivorous black drum (Pogonias cromis) and the generalist red drum (Sciaenops ocellatus). Muscle activity patterns were recorded simultaneously from eight pharyngeal muscles. Electromyographic (EMG) activity was recorded during feeding on three prey types that varied in shell hardness. Canonical variate and discriminant function analyses were used to describe the distinctness of drum pharyngeal processing behaviors. Discriminant functions built of EMG timing variables were more accurate than muscle activity intensity at identifying cycles by prey type and species. Both drum species demonstrated the ability to modulate pharyngeal motor patterns in response to prey hardness. The mean motor patterns and the canonical variate space of crushing behavior indicated that black drum employed a novel motor pattern during molluscivory. The mollusc-crushing motor pattern of black drum is different from other neoteleost pharyngeal behaviors in lacking upper jaw retraction by the retractor dorsalis muscle. This functional modification suggests that crushing hard-shelled marine bivalves requires a 'vice-like' compression bite in contrast to the shearing forces that are applied to weaker-shelled fiddler crabs by red drum and to freshwater snails by redear sunfish.

  14. 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.

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

    PubMed

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

    2016-09-23

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

  16. 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. 

  17. A fossil unicorn crestfish (Teleostei, Lampridiformes, Lophotidae) from the Eocene of Iran

    PubMed Central

    2017-01-01

    Lophotidae, or crestfishes, is a family of rare deep-sea teleosts characterised by an enlarged horn-like crest on the forehead. They are poorly represented in the fossil record, by only three described taxa. One specimen attributed to Lophotidae has been described from the pelagic fauna of the middle-late Eocene Zagros Basin, Iran. Originally considered as a specimen of the fossil lophotid †Protolophotus, it is proposed hereby as a new genus and species †Babelichthys olneyi, gen. et sp. nov., differs from the other fossil lophotids by its relatively long and strongly projecting crest, suggesting a close relationship with the modern unicorn crestfish, Eumecichthys. This new taxon increases the diversity of the deep-sea teleost fauna to which it belongs, improving our understanding of the taxonomic composition of the early Cenozoic mesopelagic ecosystems. PMID:28674642

  18. The complete mitochondrial genome of the redeye mullet Liza haematocheila (Teleostei, Mugilidae).

    PubMed

    Chen, Jianhua; Li, Yinglei; Chen, Haigang; Yan, Binlun; Meng, Xueping

    2015-01-01

    The complete mitochondrial sequence of the redeye mullet Liza haematocheila has been determined. The circle genome is 16,822 bp in size, and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region. The gene order and composition of L. haematocheila was similar to that of most other teleosts. The base composition of H-strand is 26.42% (A), 26.38% (T), 16.72% (G) and 30.47% (C), with an AT content of 52.8%. All genes are encoded on the heavy strand with the exception of ND6 and eight tRNA genes. The mitochondrial genome of L. haematocheila presented will be in favor of resolving phylogenetic relationships within the family Scatophagidae and the Mugiliformes.

  19. 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. Copyright © 2015 Elsevier Inc. All rights reserved.

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

    PubMed

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

    2014-09-01

    The mullet Mugil liza occurs along the Atlantic coast of South America from Venezuela to Argentina, but 95% of the commercial catch is collected from south Brazil between São Paulo and Argentina. Mugil liza is a single spawner with oocyte development occurring synchronously in two groups. Spawning happens in marine areas and occurs after migration. The reproductive migration occurs from Argentina (38° S) to the southern Brazilian states (24-26° S) from April to July, with peak spawning in June between northern Santa Catarina and Paraná. The presence of hyaline oocytes was associated with high salinity and sea surface temperatures of 19-21° C, and followed the seasonal northward displacement of these oceanographic conditions. The average size at first maturity (Lm ) for both sexes was 408·3 mm total length, LT . Males (Lm  = 400·1) matured earlier than females (Lm  = 421·9 mm). Fecundity ranged from 818,992 to 2,869,767 oocytes (mean = 1,624,551) in fish that were between 426 and 660 mm LT . © 2014 The Fisheries Society of the British Isles.

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

    PubMed

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

    2011-06-01

    The reproductive cycles of three mullet species from the Eastern Adriatic coast were described using several biological parameters (gonado-somatic index, oocyte diameter and sex ratio) to improve knowledge about their reproduction. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

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

    PubMed

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

    2014-06-01

    Percomorpha, comprising about 60% of modern teleost fishes, has been described as the "(unresolved) bush at the top" of the tree, with its intrarelationships still being ambiguous owing to huge diversity (>15,000 species). Recent molecular phylogenetic studies based on extensive taxon and character sampling, however, have revealed a number of unexpected clades of Percomorpha, and one of which is composed of Syngnathoidei (seahorses, pipefishes, and their relatives) plus several groups distributed across three different orders. To circumscribe the clade more definitely, we sampled several candidate taxa with reference to the previous studies and newly determined whole mitochondrial genome (mitogenome) sequences for 16 percomorph species across syngnathoids, dactylopterids, and their putatively closely-related fishes (Mullidae, Callionymoidei, Malacanthidae). Unambiguously aligned sequences (13,872 bp) from those 16 species plus 78 percomorphs and two outgroups (total 96 species) were subjected to partitioned Bayesian and maximum likelihood analyses. The resulting trees revealed a highly supported clade comprising seven families in Syngnathoidei (Gasterosteiformes), Dactylopteridae (Scorpaeniformes), Mullidae in Percoidei and two families in Callionymoidei (Perciformes). We herein proposed to call this clade "Syngnathiformes" following the latest nuclear DNA studies with some revisions on the included families. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. A new species of Lobocheilos (Teleostei: Cyprinidae) from East Kalimantan, Indonesian Borneo.

    PubMed

    Ciccotto, Patrick J; Tan, Heok Hui

    2018-03-22

    Lobocheilos aurolineatus, new species, is described from the Mahakam River basin in East Kalimantan, Indonesian Borneo. It is distinguished from all other species of Lobocheilos except for L. ixocheilos and L. tenura in having one pair of barbels (maxillary) and by the presence of a broad, black midlateral stripe, approximately ¾ scale height in thickness, extending from the operculum to the caudal-peduncle base. Lobocheilos aurolineatus differs from both species in possessing a thin cream to yellow stripe on the anterior ⅔ of the flank, separating the black midlateral stripe from the brown dorso-lateral scales, and by a smaller mouth width (23.5-29.9% head length in L. aurolineatus vs. 32.1-45.0% and 34.4-46.4% head length in L. ixocheilos and L. tenura, respectively).

  4. 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.

  5. Morphology-diet relationships in four killifishes (Teleostei, Cyprinodontidae, Orestias) from Lake Titicaca.

    PubMed

    Maldonado, E; Hubert, N; Sagnes, P; De Mérona, B

    2009-02-01

    This study explores the relationship between morphology and diet in four Andean killifishes (Orestias) from Lake Titicaca that are known to differ in habitat use. Species that fed preferentially on amphipods (Orestias albus) or molluscs (Orestias luteus) separated in multivariate space from other species that feed on cladocera and algae (Orestias agassii and Orestias jussiei). Generally, specimens feeding on cladocera were characterized by a short, blunt nose with a small mouth; whereas, specimens feeding on amphipods exhibited a long snout with a large mouth. Specimens including molluscs in their diet tended to have a larger posterior part of the head and the larger opercles than others; while the occurrence of substratum in gut content was generally related to a short but deep head. The present analysis suggests that the littoral O. jussiei has an intermediate phenotype and diet between the pelagic (O. agassii) and benthic (O. albus and O. luteus) species. Results suggest that resource partitioning was occurring and that several morphological traits relate to characteristics of the diet, and it is inferred that the benthic, the pelagic and the littoral zones in the lake host different prey communities constituting distinct adaptive landscapes.

  6. A new stem-neopterygian fish from the Middle Triassic of China shows the earliest over-water gliding strategy of the vertebrates.

    PubMed

    Xu, Guang-Hui; Zhao, Li-Jun; Gao, Ke-Qin; Wu, Fei-Xiang

    2013-01-07

    Flying fishes are extraordinary aquatic vertebrates capable of gliding great distances over water by exploiting their enlarged pectoral fins and asymmetrical caudal fin. Some 50 species of extant flying fishes are classified in the Exocoetidae (Neopterygii: Teleostei), which have a fossil record no older than the Eocene. The Thoracopteridae is the only pre-Cenozoic group of non-teleosts that shows an array of features associated with the capability of over-water gliding. Until recently, however, the fossil record of the Thoracopteridae has been limited to the Upper Triassic of Austria and Italy. Here, we report the discovery of exceptionally well-preserved fossils of a new thoracopterid flying fish from the Middle Triassic of China, which represents the earliest evidence of an over-water gliding strategy in vertebrates. The results of a phylogenetic analysis resolve the Thoracopteridae as a stem-group of the Neopterygii that is more crown-ward than the Peltopleuriformes, yet more basal than the Luganoiiformes. As the first record of the Thoracopteride in Asia, this new discovery extends the geographical distribution of this group from the western to eastern rim of the Palaeotethys Ocean, providing new evidence to support the Triassic biological exchanges between Europe and southern China. Additionally, the Middle Triassic date of the new thoracopterid supports the hypothesis that the re-establishment of marine ecosystems after end-Permian mass extinction is more rapid than previously thought.

  7. Generality of vertebrate developmental patterns: evidence for a dermomyotome in fish

    PubMed Central

    Devoto, S.H.

    2012-01-01

    Summary The somitic compartment that gives rise to trunk muscle and dermis in amniotes is an epithelial sheet on the external surface of the somite, and is known as the dermomyotome. However, despite its central role in the development of the trunk and limbs, the evolutionary history of the dermomyotome and its role in non-amniotes is poorly understood. We have tested whether a tissue with the morphological and molecular characteristics of a dermomyotome exists in non-amniotes. We show that representatives of the agnathans and of all major clades of gnathostomes each have a layer of cells on the surface of the somite, external to the embryonic myotome. These external cells do not show any signs of terminal myogenic or dermogenic differentiation. Moreover, in the embryos of bony fishes as diverse as sturgeons (Chondrostei) and zebrafish (Teleostei) this layer of cells expresses the pax 3 and 7 genes that mark myogenic precursors. Some of the pax7-expressing cells also express the differentiation-promoting myogenic regulatory factor Myogenin and appear to enter into the myotome. We therefore suggest that the dermomyotome is an ancient and conserved structure that evolved prior to the last common ancestor of all vertebrates. The identification of a dermomyotome in fish makes it possible to apply the powerful cellular and genetic approaches available in zebrafish to the understanding of this key developmental structure. PMID:16409387

  8. The role of brain peptides in the reproduction of blue gourami males (Trichogaster trichopterus).

    PubMed

    Levy, Gal; Degani, Gad

    2013-10-01

    In all vertebrates, reproduction and growth are closely linked and both are controlled by complex hormonal interactions at the brain-pituitary level. In this study, we focused on the reciprocal interactions between brain peptides that regulate growth and reproductive functions in a teleostei fish (blue gourami Trichogaster trichopterus). An increase in gonadotropin-releasing hormone 1 (GnRH1) gene expression was detected during ontogeny, and this peptide increased growth hormone (GH) and β follicle-stimulating hormone (βFSH) gene expression in pituitary cell culture. However, although no change in gonadotropin-releasing hormone 2 (GnRH2) gene expression during the reproductive cycle or sexual behavior was detected, a stimulatory effect of this peptide on β gonadotropins (βGtH) gene expression was observed. In addition, pituitary adenylate cyclase-activating polypeptide 38 (PACAP-38) inhibited GnRH-analog-induced βFSH gene expression, and co-treatment of cells with GnRH-analog and PACAP-38 inhibited GnRH-analog-stimulatory and PACAP-38-inhibitory effects on GH gene expression. These findings together with previous studies were used to create a model summarizing the mechanism of brain peptides (GnRH, PACAP and its related peptide) and the relationship to reproduction and growth through pituitary hormone gene expression during ontogenesis and reproductive stages in blue gourami. © 2013 Wiley Periodicals, Inc.

  9. Molecular phylogeny and larval morphological diversity of the lanternfish genus Hygophum (Teleostei: Myctophidae).

    PubMed

    Yamaguchi, M; Miya, M; Okiyama, M; Nishida, M

    2000-04-01

    Larvae of the deep-sea lanternfish genus Hygophum (Myctophidae) exhibit a remarkable morphological diversity that is quite unexpected, considering their homogeneous adult morphology. In an attempt to elucidate the evolutionary patterns of such larval morphological diversity, nucleotide sequences of a portion of the mitochondrially encoded 16S ribosomal RNA gene were determined for seven Hygophum species and three outgroup taxa. Secondary structure-based alignment resulted in a character matrix consisting of 1172 bp of unambiguously aligned sequences, which were subjected to phylogenetic analyses using maximum-parsimony, maximum-likelihood, and neighbor-joining methods. The resultant tree topologies from the three methods were congruent, with most nodes, including that of the genus Hygophum, being strongly supported by various tree statistics. The most parsimonious reconstruction of the three previously recognized, distinct larval morphs onto the molecular phylogeny revealed that one of the morphs had originated as the common ancestor of the genus, the other two having diversified separately in two subsequent major clades. The patterns of such diversification are discussed in terms of the unusual larval eye morphology and geographic distribution. Copyright 2000 Academic Press.

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

    PubMed

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

    2016-05-01

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

  11. 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.

  12. Schistura maculosa, a new species of loach (Teleostei: Nemacheilidae) from Mizoram, northeastern India.

    PubMed

    Lalronunga, Samuel; Lalnuntluanga; Lalramliana

    2013-01-01

    Schistura maculosa, a new species of loach, is described from Tuingo and Pharsih Rivers, tributaries of Tuivai River (Barak drainage) in Mizoram, northeastern India. It is distinguished from other closely related Schistura species in having an axillary pelvic lobe; an incomplete lateral line; 20-30 narrow black bars on the body; 3-4 rows of black spots horizontally across the dorsal-fin; a slightly emarginate caudal-fin, with 5-7 rows of black spots more or less regularly arranged vertically on rays across the fin, and 8+8 branched caudal-fin rays.

  13. The complete mitochondrial genome of the three-spot seahorse, Hippocampus trimaculatus (Teleostei, Syngnathidae).

    PubMed

    Chang, Chia-Hao; Shao, Kwang-Tsao; Lin, Yeong-Shin; Liao, Yun-Chih

    2013-12-01

    The complete mitochondrial genome of the three-spot seahorse was sequenced using a polymerase chain reaction-based method. The total length of mitochondrial DNA is 16,535 bp and includes 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a control region. The mitochondrial gene order of the three-spot seahorse also conforms to the distinctive vertebrate mitochondrial gene order. The base composition of the genome is A (32.7%), T (29.3%), C (23.4%), and G (14.6%) with an A + T-rich hallmark as that of other vertebrate mitochondrial genomes.

  14. The complete mitochondrial genome of the tiger tail seahorse, Hippocampus comes (Teleostei, Syngnathidae).

    PubMed

    Chang, Chia-Hao; Lin, Han-Yang; Jang-Liaw, Nian-Hong; Shao, Kwang-Tsao; Lin, Yeong-Shin; Ho, Hsuan-Ching

    2013-06-01

    The complete mitochondrial genome of the tiger tail seahorse was sequenced using a polymerase chain reaction-based method. The total length of mitochondrial DNA is 16,525 bp and includes 13 protein-coding genes, 2 ribosomal RNA, 22 transfer RNA genes, and a control region. The mitochondrial gene arrangement of the tiger tail seahorse is also matching the one observed in the most vertebrate creatures. Base composition of the genome is A (32.8%), T (29.8%), C (23.0%), and G (14.4%) with an A+T-rich hallmark as that of other vertebrate mitochondrial genomes.

  15. Pituitary gland morphogenesis and ontogeny of adenohypophyseal cells of Salminus brasiliensis (Teleostei, Characiformes).

    PubMed

    de Jesus, Lázaro Wender Oliveira; Chehade, Chayrra; Costa, Fabiano Gonçalves; Borella, Maria Inês

    2014-06-01

    In this study, we describe for the first time the details of the pituitary gland morphogenesis and the ontogeny of adenohypophyseal cells of a South American Characiform species with great importance for Brazilian Aquaculture, Salminus brasiliensis (Characiformes, Characidae), from hatching to 25 days after hatching (dah), by histochemical and immunocytochemical methods. The pituitary placode was first detected at hatching (0 dah), and the pituitary anlage became more defined at 0.5 dah. The neurohypophysis (NH) development started at 3 dah, and the early formation of its stalk at 12.5 dah. An increase in adenohypophyseal and NH tissues was also observed, and in juveniles at 25 dah, the pituitary displayed similar morphology to that found in adults of this species, displaying the main features of the teleost pituitary. PRL cells were detected at 0.5 dah, together with ACTH and α-MSH cells, followed by GH and SL cells at 1.5 dah. β-FSH cells were detected at 25 dah, while β-LH cells at 5 dah. The pituitary development in this species comprises a dynamic process similar to other teleosts. Our findings in S. brasiliensis corroborate the heterogeneity in the ontogeny of adenohypophyseal cells in teleosts and suggest a role for adenohypophyseal hormones in the early development of this species.

  16. Phylogenetic analysis shows the general diversification pattern of deep-sea notacanthiforms (Teleostei: Elopomorpha).

    PubMed

    Barros-García, David; Froufe, Elsa; Bañón, Rafael; Carlos Arronte, Juan; de Carlos, Alejandro

    2018-07-01

    The Notacanthiformes is an ancient group of deep-sea ray-finned fishes comprising 27 species in two families; Halosauridae and Notacanthidae. Although many studies have tried to reconstruct the phylogenetic relationships among the major clades of Elopomorpha, little is known about the evolutionary history of notacanthiforms. Molecular and morphological data were used to test previous hypotheses regarding the phylogenetic relationships among notacanthiform taxa, and to unravel the origin and evolution of this group. The molecular analyses of notacanthids showed similar results to those previously obtained employing osteological data, which proposed the existence of the Lipogenyinae (Lipogenys) and Notacanthinae (Notacanthus + Polyacanthonotus) subfamilies. Nevertheless, when the external morphology data is considered Lipogenys is more related to Notacanthus than Polyacanthonotus. The analyses could not fully resolve the inner relationships of the halosaurids. The time-calibrated tree of the order Notacanthiformes shows a long process of diversification spanning from the upper Cretaceous, to 50 million years after the K-Pg extinction, with the gradual emergence of all the modern families and genera of the group. This is the first specific phylogeny of the order Notacanthiformes, combining different analyses and data in order to obtain a wider perspective of the evolution and diversification of this group of fishes. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Description of a new species of Triplophysa (Teleostei: Nemacheilidae) from Guizhou Province, China.

    PubMed

    Wu, W J; He, A Y; Yang, J X; Du, L N

    2018-06-07

    A new cave-dwelling fish species Triplophysa guizhouensis is described based on specimens collected from Guizhou, China, in a subterranean system interconnected with the Hongshui River drainage. The species can be distinguished from its congeners by a combination of characters: eyes present; caudal fin with 14 branched rays; inner gill rakers of first gill arch 8-10; posterior chamber of air bladder developed; and body posterior of dorsal fin scaled. A key to species of Triplophysa in the Pearl River basin is provided. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  18. 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.

  19. Two new species of shovel-jaw carp Onychostoma (Teleostei: Cyprinidae) from southern Vietnam.

    PubMed

    Hoang, Huy Duc; Pham, Hung Manh; Tran, Ngan Trong

    2015-05-22

    Two new species of large shovel-jaw carps in the genus Onychostoma are described from the upper Krong No and middle Dong Nai drainages of the Langbiang Plateau in southern Vietnam. These new species are known from streams in montane mixed pine and evergreen forests between 140 and 1112 m. Their populations are isolated in the headwaters of the upper Sre Pok River of the Mekong basin and in the middle of the Dong Nai basin. Both species are differentiated from their congeners by a combination of the following characters: transverse mouth opening width greater than head width, 14-17 predorsal scales, caudal-peduncle length 3.9-4.2 times in SL, no barbels in adults and juveniles, a strong serrated last simple ray of the dorsal fin, and small eye diameter (20.3-21.5% HL). Onychostoma krongnoensis sp. nov. is differentiated from Onychostoma dongnaiensis sp. nov. by body depth (4.0 vs. 3.2 times in SL), predorsal scale number (14-17 vs. 14-15), dorsal-fin length (4.5 vs. 4.2 times in SL), caudal-peduncle length (3.9 vs. 4.2 times in SL), colour in life (dark vs. bright), and by mitochondrial DNA (0.2% sequence divergence). Molecular evidence indicates that both species are members of Onychostoma and are distinct from all congeners sampled (uncorrected sequence divergences at the 16S rRNA gene of >2.0% for all Onychostoma for which homologous 16S rRNA sequences are available).

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

    PubMed

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

    2015-01-01

    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. 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. 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.

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

    PubMed Central

    Bichuette, Maria Elina

    2017-01-01

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

  2. Trends in Karyotype Evolution in Astyanax (Teleostei, Characiformes, Characidae): Insights From Molecular Data

    PubMed Central

    Pazza, Rubens; Dergam, Jorge A.; Kavalco, Karine F.

    2018-01-01

    The study of patterns and evolutionary processes in neotropical fish is not always an easy task due the wide distribution of major fish groups in large and extensive river basins. Thus, it is not always possible to detect or correlate possible effects of chromosome rearrangements in the evolution of biodiversity. In the Astyanax genus, chromosome data obtained since the 1970s have shown evidence of cryptic species, karyotypic plasticity, supernumerary chromosomes, triploidies, and minor chromosomal rearrangements. In the present work, we map and discuss the main chromosomal events compatible with the molecular evolution of the genus Astyanax (Characiformes, Characidae) using mitochondrial DNA sequence data, in the search for major chromosome evolutionary trends within this taxon. PMID:29713335

  3. Digestive proteinases of Brycon orbignyanus (Characidae, Teleostei): characteristics and effects of protein quality.

    PubMed

    García-Carreño, Fernando L; Albuquerque-Cavalcanti, Cristiane; Navarrete del Toro, M Angeles; Zaniboni-Filho, Evoy

    2002-06-01

    Juvenile piracanjuba, Brycon orbignyanus, in the wild consume protein from both plant and animal sources. Digestion of protein in piracanjuba begins in the stomach with pepsin, at low pH, and is followed by hydrolysis at alkaline pH in the lumen of the intestine. The digestive system in piracanjuba was evaluated to characterize the enzymes responsible for the digestion of feed protein and their composition. The gastric tissue synthesizes pepsin and the intestine tissues trypsin and chymotrypsin. Operational variables were evaluated and defined for future studies of the digestive system physiology. The enzymatic activity in the intestine and the relative concentration of enzymes were heavily influenced by the composition of the feed and the feeding regime, as detected by substrate-SDS-PAGE. Piracanjuba possess a mechanism of enzyme adaptation responding to food quality and regime, by varying the amount and composition of digestive proteases. This is a requisite study to determine the enzymes digesting protein in food and their characteristics and to gain some clues about the possible regulation mechanisms of enzyme synthesis in piracanjuba.

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

    PubMed

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

    2008-05-01

    Many predatory deep-sea fishes show highly specialized modifications of their feeding apparatus, e.g., elongate jaws studded with long daggerlike teeth, often combined with a very distensible stomach, to be capable of swallowing relatively large prey. These striking features can be observed in members of the marine teleost family Stomiidae. The present study gives a detailed morphological description of the mesopelagic predatory fish, Stomias boa, based on a combined approach of clearing and double staining, serial sections and dissection. In this genus, large pads made of dense connective tissue extend from the first enlarged neural arch to the ventral side of the chordal sheath, embracing the prominent exoccipitals and thus constituting a kind of double ball- and socket joint for the head. The notochordal occipito-vertebral gap is enlarged, probably not by loss of vertebral centra as is proposed for other genera of the stomiid family, e.g., in Astronesthes or Photostomias. We conclude that this "pseudo-craniovertebral articulation" serves as a functional substitute for the absent vertebrae and strengthens the flexible, anterior part of the vertebral column during extreme dorsal expansion of the gape during prey capture and swallowing. (c) 2007 Wiley-Liss, Inc.

  5. Functional analysis of a specialized prey processing behavior: winnowing by surfperches (Teleostei: Embiotocidae).

    PubMed

    Drucker, E G; Jensen, J S

    1991-12-01

    Several surfperches (Embiotocidae), including the black surfperch, Embiotoca jacksoni, exhibit a specialized prey handling behavior known as winnowing, in which ingested food and non-nutritive debris are separated within the oropharyngeal cavity. Prey items are swallowed, and unpalatable material is ejected from the mouth. Winnowing is believed to play an important role in the partitioning of food resources among sympatric embiotocids. We present a mechanistic model for this separative prey processing based on high-speed video analysis, cineradiography, electromyography, and buccal and opercular cavity pressure transducer recording. Winnowing by embiotocids is characterized by premaxillary protrusions repeated cyclically with reduced oral gape. Protrusion is accompanied by depression of the hyoid apparatus and adduction of the opercula. Alternating expansion and contraction of the buccal and opercular cavities generate regular pressure waveforms that indicate bidirectional water flow during processing. Separation of food from debris by Embiotoca jacksoni occurs in three phases. The prey-debris bolus is transported anteriorly and posteriorly within the oropharyngeal cavity and is then sheared by the pharyngeal jaws. Mechanical processing is complemented by the rinsing action of water currents during hydraulic prey transport. The feeding apparatus of Embiotoca jacksoni is functionally versatile, although not obviously specialized relative to that of nonwinnowing surfperches. Protrusion of the premaxillae and depression of the hyoid apparatus are critical to both prey capture and subsequent prey processing. The pharyngeal jaws exhibit kinematic patterns during separation of food from debris distinct from those observed during mastication of uncontaminated prey. This behavioral flexibility facilitates resource partitioning and the coexistence of E. jacksoni in sympatric embiotocid assemblages.

  6. 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

  7. The identity of Pethia punctata, a senior synonym of P. muvattupuzhaensis (Teleostei: Cyprinidae).

    PubMed

    Katwate, Unmesh; Baby, Fibin; Raghavan, Rajeev; Dahanukar, Neelesh

    2014-11-14

    Francis Day described Pethia punctata from Cochin, on the Malabar (south western) coast of India. Although, the species is now recovered from its synonymy with P. ticto, an accurate diagnosis and description have been lacking. A redescription of P. punctata based on external morphology, osteology and genetics is provided, which revealed that P. muvattupuzhaensis, described from Muvattupuzha River, Ernakulam District, Kerala, India, is its junior synonym. Pethia punctata can be diagnosed from other known species in the genus by a combination of characters including lateral line complete, with 23-25 pored scales; 8 predorsal scales; ½4/1/3½ scales in transverse line; dorsal fin originating almost opposite to, or slightly before pelvic-fin origin; gill rakers 7 on first ceratobranchial; 4+26 total vertebrae; a small black humeral spot covering anterior half of the fourth scale of the row below the lateral-line row; two minute dark spots below the humeral spot; a prominent spot on the caudal peduncle, surrounded by a golden hoop covering scales 19-21 of the lateral-line row; and dorsal fin with 2-3 longitudinal rows of black spots, third row occupying only anterior portion of the fin. 

  8. 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

    2015-12-23

    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.

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-09-19

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

  12. Strong reproductive skew among males in the multiply mated swordtail Xiphophorus multilineatus (Teleostei).

    PubMed

    Luo, J; Sanetra, M; Schartl, M; Meyer, A

    2005-01-01

    Male swordtails in the genus Xiphophorus display a conspicuous ventral elongation of the caudal fin, the sword, which arose through sexual selection due to female preference. Females mate regularly and are able to store sperm for at least 6 months. If multiple mating is frequent, this would raise the intriguing question about the role of female choice and male-male competition in shaping the mating system of these fishes. Size-dependent alternate mating strategies occur in Xiphophorus; one such strategy is courtship with a sigmoid display by large dominant males, while the other is gonopodial thrusting, in which small subordinate males sneak copulations. Using microsatellite markers, we observed a frequency of multiple paternity in wild-caught Xiphophorus multilineatus in 28% of families analyzed, but the actual frequency of multiple mating suggested by the correction factor PrDM was 33%. The number of fathers contributing genetically to the brood ranged from one to three. Compared to other species in the family Poeciliidae, both frequency and degree of multiple paternity were low. Paternity was found to be highly skewed, with one male on average contributing more than 70% to the offspring. Hence in this Xiphophorus mating system, typically one male dominates and sneaker males do not appear to be particularly effective. Postcopulatory mechanisms, however, such as sperm competition, are also indicated by our data, using sex-linked phenotypes among the offspring.

  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. Embryonic Developmental Stages of African Giant Catfish Heterobranchus longifilis (Valenciennes, 1840) (Teleostei, Clariidae)

    NASA Astrophysics Data System (ADS)

    Wilfred-Ekprikpo, P. C.

    2016-02-01

    One of the major challenges confronting the globe is the issue of food insecurity. This problem results from inadequate protein intake by humans especially those people from the third world countries. In order to arrest this ugly situation, there is the need to increase protein production by intensifying aquaculture. In sub-saharan Africa, particularly Nigeria, the major aquaculture species is African mud catfish (Clarias gariepinus) and its production has increase protein output but the protein deficit is still wide. Thus, necessitating the need to develop other aquaculture species endemic to the region. One of these species is Heterobranchus and there successful breeding depending on a good understanding of their biology. The embryonic developmental stages of Heterobranchus longifilis in freshwater tanks were determined. The first cleavage cell division occurred 30 minutes after fertilization of eggs while, the morula stage was observed within 2 hours. The blastula stage occurred between 2 and 8 hours, while the gastrula stage occurred between 12 and 18 hours. Thereafter, neurulation period, and embryonic body formation appeared. The optical vesicle and auditory vesicle formed. Finally muscular contraction, tail formation, heartbeat and hatching occurred. The embryonic developmental stage of H. longifilis started immediately the oocyte (egg) was fertilized and terminated when the embryo hatched from the chorion membranous wall. The young larva emerged from the embryonic membrane at 24.46 hrs with vigorous lashing of the caudal region against the chorion membrane. The average weight and length of the yolk larvae were 0.005g and 0.43 cm respectively. The percentage fertilization and hatchability rates were 82.50 and 65.10% respectively. The experiment revealed that Heterobranchus longifilis could be a good aquaculture species.

  15. Tooth development in Ambystoma mexicanum: phosphatase activities, calcium accumulation and cell proliferation in the tooth-forming tissues.

    PubMed

    Wistuba, Joachim; Ehmcke, Jens; Clemen, Günter

    2003-06-01

    Prerequisites of tooth formation, cell proliferation in the tooth-forming tissues, calcium accumulation and the enzymatic activities of alkaline (ALP) and acid phosphatases (ACP) were investigated by immunohistochemical and histochemical methods in various developmental stages of the Mexican Axolotl, Ambystoma mexicanum. During the growth of replacement teeth, the tooth-forming tissues continually recruit cells from the surrounding regions. The basal layer of the oral epithelium, the dental lamina and sometimes even the outer enamel epithelium provide cells for the differentiated inner enamel epithelium, in which the active ameloblasts are localized. The differentiating odontoblasts are derived from proliferating cells situated basally to the replacement teeth in the mesenchymal tissue. When differentiation has started and the cells have become functional, proliferative activity can no longer be observed. Calcium is accumulated close to the site of mineralization in the inner enamel epithelium and in the odontoblasts as it is in mammals, elasmobranchii and teleostei. The activities of ACP and ALP related to the mineralization of the replacement teeth are separated spatially and not sequentially as they are in mammals. However, the results indicate a similar function of these enzymatic components in relation to tooth formation and maturation of mineral deposition. Most of the substantial processes related to tooth formation reported from other vertebrates occur in a manner similar to that in Ambystoma mexicanum, but there also seem to be basic mechanisms present that are realised in a unique way in this urodele.

  16. Fishing for gaps in science: a bibliographic analysis of Brazilian freshwater ichthyology from 1986 to 2005.

    PubMed

    Azevedo, P G; Mesquita, F O; Young, R J

    2010-06-01

    To investigate Brazilian freshwater ichthyology, from 1986 to 2005, a bibliometric analysis was conducted using abstracts downloaded from The Web of Science database searching for the keywords 'fish', 'pisces', 'teleostei' and the address field having the word 'Brazil'. The results of this study showed that Brazilian freshwater ichthyology publications have been increasing during the study period. This process is a consequence of a series of investments that the Brazilian Government has made. Furthermore, data analyses identified scientific areas where there was a lack of scientific knowledge (e.g. studies of species threatened with extinction and certain hydrologic basins). Research institutions from the north-east and northern region of Brazil had the lowest participation in scientific productivity, which was a reflection of their regions poorer economic situation. This study showed that scientific productivity in Brazilian ichthyology was a direct reflection of state investment in research. Furthermore, data in this study follow expected statistical probabilities, for example, fishes from the most diverse families were the most studied. Thus, the study shows that great progress has been made by Brazilian ichthyologists in the last 20 years; however, due to the mega diversity of fishes in Brazil, much remains to be done if many species are to become known to science and to be saved from extinction. This it seems will depend on continued and further investment by Brazilian Government funding agencies, as Brazilian ichthyologists have demonstrated their capacity to generate high quality information about their study species.

  17. A new stem-neopterygian fish from the Middle Triassic of China shows the earliest over-water gliding strategy of the vertebrates

    PubMed Central

    Xu, Guang-Hui; Zhao, Li-Jun; Gao, Ke-Qin; Wu, Fei-Xiang

    2013-01-01

    Flying fishes are extraordinary aquatic vertebrates capable of gliding great distances over water by exploiting their enlarged pectoral fins and asymmetrical caudal fin. Some 50 species of extant flying fishes are classified in the Exocoetidae (Neopterygii: Teleostei), which have a fossil record no older than the Eocene. The Thoracopteridae is the only pre-Cenozoic group of non-teleosts that shows an array of features associated with the capability of over-water gliding. Until recently, however, the fossil record of the Thoracopteridae has been limited to the Upper Triassic of Austria and Italy. Here, we report the discovery of exceptionally well-preserved fossils of a new thoracopterid flying fish from the Middle Triassic of China, which represents the earliest evidence of an over-water gliding strategy in vertebrates. The results of a phylogenetic analysis resolve the Thoracopteridae as a stem-group of the Neopterygii that is more crown-ward than the Peltopleuriformes, yet more basal than the Luganoiiformes. As the first record of the Thoracopteride in Asia, this new discovery extends the geographical distribution of this group from the western to eastern rim of the Palaeotethys Ocean, providing new evidence to support the Triassic biological exchanges between Europe and southern China. Additionally, the Middle Triassic date of the new thoracopterid supports the hypothesis that the re-establishment of marine ecosystems after end-Permian mass extinction is more rapid than previously thought. PMID:23118437

  18. Do freshwater fishes diversify faster than marine fishes? A test using state-dependent diversification analyses and molecular phylogenetics of new world silversides (atherinopsidae).

    PubMed

    Bloom, Devin D; Weir, Jason T; Piller, Kyle R; Lovejoy, Nathan R

    2013-07-01

    Freshwater habitats make up only ∼0.01% of available aquatic habitat and yet harbor 40% of all fish species, whereas marine habitats comprise >99% of available aquatic habitat and have only 60% of fish species. One possible explanation for this pattern is that diversification rates are higher in freshwater habitats than in marine habitats. We investigated diversification in marine and freshwater lineages in the New World silverside fish clade Menidiinae (Teleostei, Atherinopsidae). Using a time-calibrated phylogeny and a state-dependent speciation-extinction framework, we determined the frequency and timing of habitat transitions in Menidiinae and tested for differences in diversification parameters between marine and freshwater lineages. We found that Menidiinae is an ancestrally marine lineage that independently colonized freshwater habitats four times followed by three reversals to the marine environment. Our state-dependent diversification analyses showed that freshwater lineages have higher speciation and extinction rates than marine lineages. Net diversification rates were higher (but not significant) in freshwater than marine environments. The marine lineage-through time (LTT) plot shows constant accumulation, suggesting that ecological limits to clade growth have not slowed diversification in marine lineages. Freshwater lineages exhibited an upturn near the recent in their LTT plot, which is consistent with our estimates of high background extinction rates. All sequence data are currently being archived on Genbank and phylogenetic trees archived on Treebase. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  19. Phylogenomics reveals habitat-associated body shape divergence in Oryzias woworae species group (Teleostei: Adrianichthyidae).

    PubMed

    Mokodongan, Daniel F; Montenegro, Javier; Mochida, Koji; Fujimoto, Shingo; Ishikawa, Asano; Kakioka, Ryo; Yong, Lengxob; Mulis; Hadiaty, Renny K; Mandagi, Ixchel F; Masengi, Kawilarang W A; Wachi, Nakatada; Hashiguchi, Yasuyuki; Kitano, Jun; Yamahira, Kazunori

    2018-01-01

    The Oryzias woworae species group, composed of O. asinua, O. wolasi, and O. woworae, is widely distributed in southeastern Sulawesi, an island in the Indo-Australian Archipelago. Deep-elongated body shape divergence is evident among these three species to the extent that it is used as a species-diagnostic character. These fishes inhabit a variety of habitats, ranging from upper streams to ponds, suggesting that the body shape divergence among the three species may reflect adaptation to local environments. First, our geometric morphometrics among eight local populations of this species group revealed that the three species cannot be separated by body shape and that riverine populations had more elongated bodies and longer caudal parts than lacustrine populations. Second, their phylogenetic relationships did not support the presence of three species; phylogenies using mitochondrial DNA and genomic data obtained from RNA-Seq revealed that the eight populations could not be sorted into three different clades representing three described species. Third, phylogenetic corrections of body shape variations and ancestral state reconstruction of body shapes demonstrated that body shape divergence between riverine and lacustrine populations persisted even if the phylogenies were considered and that body shape evolved rapidly irrespective of phylogeny. Sexual dimorphism in body shape was also evident, but the degree of dimorphism did not significantly differ between riverine and lacustrine populations after phylogenetic corrections, suggesting that sexual selection may not substantially contribute to geographical variations in body shape. Overall, these results indicate that the deep-elongated body shape divergence of the O. woworae species group evolved locally in response to habitat environments, such as water currents, and that a thorough taxonomic reexamination of the O. woworae species group may be necessary. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    USGS Publications Warehouse

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

    2002-01-01

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

  1. Reanalysis and revision of the complete mitochondrial genome of Rachycentron canadum (Teleostei, Perciformes, Rachycentridae).

    PubMed

    Musika, Jidapa; Khongchatee, Adison; Phinchongsakuldit, Jaros

    2014-08-01

    The complete mitochondrial genome of cobia, Rachycentron canadum, was reanalyzed and revised. The genome is 18,008 bp in length, containing 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and a control region or displacement loop (D-loop). The gene arrangement is identical to that observed in most vertebrates. Base composition on the heavy strand is 30.14% A, 25.22% C, 15.80% G and 28.84% T. The D-loop region exhibits an A + T rich pattern, containing short tandem repeats of TATATACATGG, TATATGCACAA and TATATGCACGG. The mitochondrial genome studied differs from the previously published genome in two segments; the control region to 12S and ND5 to tRNA(Glu). The 12S sequence also differs from those published in the databases. Phylogeny analyses revealed that the differences could be due to errors in sequence assembly and/or sample misidentification of the previous studies.

  2. 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

  3. The reproduction of Blennius pavo (Teleostei, Blenniidae). I. Ovarial cycle, environmental factors and feeding

    NASA Astrophysics Data System (ADS)

    Patzner, Robert A.

    1983-03-01

    Blennius (Salaria) pavo is a very common coastal fish in the Mediterranean Sea. The development of the ovary was studied over a period of one year; seven stages of oogenesis are described. Ripe eggs are carried during the spawning season from Juni to August. The ovary shows a resting period of more than half a year (September to March). Environmental factors of the study area such as surface water temperature and daylength are described as well as the condition factors of male and female fish. Observations on food and behaviour during the winter months are also included.

  4. Barcoding snakeheads (Teleostei, Channidae) revisited: Discovering greater species diversity and resolving perpetuated taxonomic confusions

    PubMed Central

    Conte-Grand, Cecilia; Britz, Ralf; Dahanukar, Neelesh; Raghavan, Rajeev; Pethiyagoda, Rohan; Tan, Heok Hui; Hadiaty, Renny K.; Yaakob, Norsham S.

    2017-01-01

    Snakehead fishes of the family Channidae are predatory freshwater teleosts from Africa and Asia comprising 38 valid species. Snakeheads are important food fishes (aquaculture, live food trade) and have been introduced widely with several species becoming highly invasive. A channid barcode library was recently assembled by Serrao and co-workers to better detect and identify potential and established invasive snakehead species outside their native range. Comparing our own recent phylogenetic results of this taxonomically confusing group with those previously reported revealed several inconsistencies that prompted us to expand and improve on previous studies. By generating 343 novel snakehead coxI sequences and combining them with an additional 434 coxI sequences from GenBank we highlight several problems with previous efforts towards the assembly of a snakehead reference barcode library. We found that 16.3% of the channid coxI sequences deposited in GenBank are based on misidentifications. With the inclusion of our own data we were, however, able to solve these cases of perpetuated taxonomic confusion. Different species delimitation approaches we employed (BIN, GMYC, and PTP) were congruent in suggesting a potentially much higher species diversity within snakeheads than currently recognized. In total, 90 BINs were recovered and within a total of 15 currently recognized species multiple BINs were identified. This higher species diversity is mostly due to either the incorporation of undescribed, narrow range, endemics from the Eastern Himalaya biodiversity hotspot or the incorporation of several widespread species characterized by deep genetic splits between geographically well-defined lineages. In the latter case, over-lumping in the past has deflated the actual species numbers. Further integrative approaches are clearly needed for providing a better taxonomic understanding of snakehead diversity, new species descriptions and taxonomic revisions of the group. PMID:28931084

  5. 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. Copyright © 2013 Wiley Periodicals, Inc.

  6. Molecular phylogeny and biogeography of the Neotropical cichlid fish tribe Cichlasomatini (Teleostei: Cichlidae: Cichlasomatinae).

    PubMed

    Musilová, Zuzana; Rícan, Oldrich; Janko, Karel; Novák, Jindrich

    2008-02-01

    We have conducted the first comprehensive molecular phylogeny of the tribe Cichlasomatini including all valid genera as well as important species of questionable generic status. To recover the relationships among cichlasomatine genera and to test their monophyly we analyzed sequences from two mitochondrial (16S rRNA, cytochrome b) and one nuclear marker (first intron of S7 ribosomal gene) totalling 2236 bp. Our data suggest that all genera except Aequidens are monophyletic, but we found important disagreements between the traditional morphological relationships and the phylogeny based on our molecular data. Our analyses support the following conclusions: (a) Aequidens sensu stricto is paraphyletic, including also Cichlasoma (CA clade); (b) Krobia is not closely related to Bujurquina and includes also the Guyanan Aequidens species A. potaroensis and probably A. paloemeuensis (KA clade). (c) Bujurquina and Tahuantinsuyoa are sister groups, closely related to an undescribed genus formed by the 'Aequidens'pulcher-'Aequidens'rivulatus groups (BTA clade). (d) Nannacara (plus Ivanacara) and Cleithracara are found as sister groups (NIC clade). Acaronia is most probably the sister group of the BTA clade, and Laetacara may be the sister group of this clade. Estimation of divergence times suggests that the divergence of Cichlasomatini started around 44Mya with the vicariance between coastal rivers of the Guyanas (KA and NIC clades) and remaining cis-andean South America, followed by evolution of the Acaronia-Laetacara-BTA clade in Western Amazon, and the CA clade in the Eastern Amazon. Vicariant divergence has played importantly in evolution of cichlasomatine genera, with dispersal limited to later range extension of species within genera.

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

    PubMed

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

    2013-05-01

    A comparative study of the reproductive organs in 17 of the 30 species of the tribe Starksiini (Labrisomidae, Blenniiformes) and related labrisomids reveals the major traits of gamete form and production and likely reproductive modes. The testes are of the lobular type and have a testicular gland and sperm ducts. Isodiametric sperm (aquasperm) with a globular head or anisodiametric sperm (introsperm) with an elongate head, or both, were observed in the studied species. Both types have either one or two flagella in the sperm tail. Ovaries of the Starksiini are bilobed and exhibit synchronous or asynchronous egg production. Although viviparity or "ovoviviparity" reportedly characterizes the group, our study revealed evidence of both internal and external fertilization and three modes of reproduction. External fertilization or ovuliparity is suggested for the Starksia atlantica and S. lepicoelia species complexes by the presence in males of a short genital papilla that is not reinforced through adhesion with the first anal-fin spine and by the absence of sperm within the ovaries. Internal fertilization and zygoparity is indicated for most species by the presence of an intromittent papilla in males that is adhered to the first anal-fin spine, "nests" of sperm within the ovaries, absence of embryos within the ovarian lamellae and usually thick egg envelopes bearing dense covers of adhesive filaments. Internal fertilization and embryoparity is indicated for starksia fulva and Xenomedea rhodopyga by an intromittent papilla that is adhered to the first anal-fin spine of males, anisodiametric sperm in males, delicate egg envelopes without adhesive filaments and developing embryos within follicular envelopes or within the follicle in females. Although many of these features are seen in the internally fertilizing clinid blennies, starksiins differ in retaining the testicular gland typical of labrisomids and in lacking sperm packaging typical of other internally fertilizing teleosts. Copyright © 2013 Wiley Periodicals, Inc.

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

    PubMed Central

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

    2015-01-01

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

  9. 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

    2016-01-01

    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.

  10. Androgen-induced pseudo-hermaphroditic phenotypes in female Brevimyrus niger Günther 1866 (Teleostei, Mormyridae).

    PubMed

    Stell, Sonja K; Moller, Peter

    2017-12-01

    This paper explores the plasticity of sexually dimorphic characters in subadult female Brevimyrus niger, an African weakly electric mormyrid species. Thirty-five fish were exposed in a staggered fashion (five fish a week) to aromatizable 17α-methyltestosterone over a period of 7 weeks; 18 fish served as untreated controls. 17α-MT induced precocious vitellogenesis that mirrored the natural maturational process during seasonal ovarian recrudescence. At the same time, 17α-MT exposure resulted in complete masculinization of the females' anal fin support structure normally observed during rainy season in adult males. We discuss possible hormonal mechanisms acting along the brain-pituitary-gonad axis that would explain the occurrence of precocious vitellogenesis and the male-typical transformation of the female's anal fin ray bases. Our findings are relevant to commercial aquaculture as the use of 17α-MT in fish hatcheries can pose serious environmental issues.

  11. No evidence for the radiation time lag model after whole genome duplications in Teleostei

    PubMed Central

    Laurent, Sacha; Salamin, Nicolas

    2017-01-01

    The short and long term effects of polyploidization on the evolutionary fate of lineages is still unclear despite much interest. First recognized in land plants, it has become clear that polyploidization is widespread in eukaryotes, notably at the origin of vertebrates and teleost fishes. Many hypotheses have been proposed to link the species richness of lineages and whole genome duplications. For instance, the radiation time lag model suggests that paleopolyploidy would favour the apparition of new phenotypic traits, although the radiation of the lineage would not occur before a later dispersion event. Some results indicate that this model may be observed during land plant evolution. In this work, we test predictions of the radiation time lag model using both fossil data and molecular phylogenies in ancient and more recent teleost whole genome duplications. We fail to find any evidence of delayed increase of the species number after any of these events and conclude that paleopolyploidization still remains to be unambiguously linked to taxonomic diversity in teleosts. PMID:28426792

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

    PubMed

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

    2016-07-01

    With this work we addressed some molecular systematic issues within the Mugil cephalus species complex. Particular attention was paid to the debated situations of: (i) Mugil liza, occurring in partial sympatry with Mugil cephalus in the northwestern Atlantic, and (ii) Mugil platanus, considered by some authors a synonymy of the former species and distributed in the southwestern Atlantic. We sequenced 79 individuals of a 465-bp portion of the mitochondrial control region (CR) from 8 western Atlantic and 2 Mediterranean localities. In addition, all CR sequences available from GenBank for the studied taxa were added to our dataset, for a total of 323 individuals. Overall, 229 haplotypes corresponding to 8 divergent monophyletic lineages were detected. Results of phylogenetic analyses were consistent with the occurrence of past speciation events producing the observed lineages. Of these lineages, 7 correspond to cryptic species and one is constituted by M. liza and M. platanus. As a matter of fact, these 2 taxa constitute a single lineage within the M. cephalus species complex. However, individuals of M. liza/M. platanus lineage analyzed by means of the 18 mitochondrial markers available in GenBank exhibited a degree of genetic diversity consistent with highly divergent populations. Of the 8 lineages detected, the Mediterraean one (type locality) corresponds to M. cephalus; the lineage M. liza/M. platanus should be named M. liza, under the priority principle, and the left 6 lineages need formal description. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

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

    PubMed

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

    2012-01-01

    A comprehensive mitochondrial phylogeny of the family Mugilidae (Durand et al., Mol. Phylogenet. Evol. 64 (2012) 73-92) demonstrated the polyphyly or paraphyly of a proportion of the 20 genera in the family. Based on these results, here we propose a revised classification with 25 genera, including 15 genera currently recognized as valid (Agonostomus, Aldrichetta, Cestraeus, Chaenomugil, Chelon, Crenimugil, Ellochelon, Joturus, Mugil, Myxus, Neomyxus, Oedalechilus, Rhinomugil, Sicamugil and Trachystoma), 7 resurrected genera [Dajaus (for Agonostomus monticola), Gracilimugil (for Liza argentea), Minimugil (for Sicamugil cascasia), Osteomugil (for several species currently under Moolgarda and Valamugil, including M. cunnesius, M. engeli, M. perusii, and V. robustus), Planiliza (for Indo-Pacific Chelon spp., Indo-Pacific Liza spp., and Paramugil parmatus), Plicomugil (for Oedalechilus labiosus), and Squalomugil (for Rhinomugil nasutus)] and 3 new genera: Neochelon gen. nov. (for Liza falcipinnis), Parachelon gen. nov. (for L. grandisquamis) and Pseudomyxus gen. nov. (for Myxus capensis). Genus Chelon was shown to include exclusively Chelon spp. and Liza spp. from the Atlantic and the Mediterranean, and Liza spp. species endemic to eastern southern Africa. Genus Crenimugil should now include C. crenilabis, Moolgarda seheli and V. buchanani. Genus names Liza, Moolgarda, Paramugil, Valamugil and Xenomugil should be abandoned because they are no longer valid. Further genetic evidence is required to confirm or infirm the validity of the genus Paracrenimugil Senou 1988. The mitochondrial phylogeny of the 25 genera from the present revision is the following: [(Sicamugil, (Minimugil, Rhinomugil)); Trachystoma; ((Myxus, Neomyxus), (Cestraeus, Chaenomugil, (Agonostomus, Dajaus, Joturus), Mugil)); (Aldrichetta, Gracilimugil); Neochelon gen. nov.; (Pseudomyxus gen. nov., (Chelon, Oedalechilus, Planiliza, Parachelon gen. nov.)); ((Squalomugil, (Ellochelon, Plicomugil)), (Crenimugil, Osteomugil))]. Agonostomus monticola and several species with large distribution ranges (including Moolgarda seheli, Mugil cephalus and M. curema) consist of separate lineages whose geographic distribution suggests they are cryptic species, thus warranting further taxonomic work in the Mugilidae at the infra-generic level. Copyright © 2012 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  14. 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.

  15. 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

  16. Badis britzi, a new percomorph fish (Teleostei: Badidae) from the Western Ghats of India.

    PubMed

    Dahanukar, Neelesh; Kumkar, Pradeep; Katwate, Unmesh; Raghavan, Rajeev

    2015-04-01

    Badis britzi, the first species of the genus endemic to southern India, is described from the Nagodi tributary of the west-flowing Sharavati River in Karnataka. It is distinguished from congeners by a combination of characters including a slender body, 21-24 pored lateral-line scales and a striking colour pattern consisting of 11 bars and a mosaic of black and red pigmentation on the side of the body including the end of caudal peduncle, and the absence of cleithral, opercular, or caudal-peduncle blotches, or an ocellus on the caudal-fin base. Badis triocellus Khynriam & Sen is considered a junior synonym of B. singenensis Geetakumari & Kadu.

  17. Infection dynamics of Kudoa inornata (Cnidaria: Myxosporea) in spotted seatrout Cynoscion nebulosus (Teleostei: Sciaenidae).

    PubMed

    de Buron, Isaure; Hill-Spanik, Kristina M; Haselden, Leeann; Atkinson, Stephen D; Hallett, Sascha L; Arnott, Stephen A

    2017-12-19

    Kudoa inornata is a myxosporean parasite that develops in the somatic muscle of spotted seatrout Cynoscion nebulosus, an economically and ecologically important fish in estuaries and harbors in southeastern North America. In South Carolina (SC), USA, over 90% of wild adult spotted seatrout are infected. To inform potential mitigation strategies, we conducted 3 experiments using naïve sentinel seatrout and infectious stages of K. inornata naturally present in raw water from Charleston Harbor, SC, to determine (1) if K. inornata infection follows a seasonal pattern, and (2) how long it takes for myxospores to develop in fish muscle. Infection by K. inornata was determined by visual detection of myxospores in fish muscle squashes, and any visually negative samples were then assayed for K. inornata ribosomal DNA using novel parasite-specific PCR primers. We observed that K. inornata infection in seatrout followed a seasonal pattern, with high prevalence when water temperature was highest (27-31°C; July-September) and infections that were either covert (at ~13-15°C) or not detected (<13°C) at the lowest water temperatures in January-February. Myxospore development occurred within 476 degree-days, i.e. 2 wk in a typical SC summer. Infection was dependent on fish density, which limited presumptive actinospore dose. Our findings suggest that the life cycle of the parasite may be disrupted by preventing spore-rich seatrout carcasses (e.g. at angler cleaning stations) being thrown back into harbors and estuaries throughout the year.

  18. 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

  19. Upper temperature tolerance of loach minnow under acute, chronic, and fluctuating thermal regimes

    USGS Publications Warehouse

    Widmer, A.M.; Carveth, C.J.; Bonar, Scott A.; Simms, J.R.

    2006-01-01

    We used four methods to estimate the upper lethal temperature of loach minnow Rhinichthys cobitis: the lethal thermal method (LTM), chronic lethal method (CLM), acclimated chronic exposure (ACE) method with static temperatures, and ACE method with diel temperature fluctuations. The upper lethal temperature of this species ranged between 32??C and 38??C, depending on the method and exposure time; however, temperatures as low as 28??C resulted in slowed growth compared with the control groups. In LTM trials, we increased temperatures 0.3??C/min and death occurred at 36.8 ?? 0.2??C (mean ?? SE) for fish (37-19 mm total length) acclimated to 30??C and at 36.4 ?? 0.07??C for fish acclimated to 25??C. In CLM trials, temperatures were increased more slowly (1??C/d), allowing fish to acclimate. Mean temperature at death was 33.4 ?? 0.1??C for fish 25-35 mm and 32.9 ?? 0.4??C for fish 45-50 mm. In the ACE experiment with static temperatures, we exposed fish for 30 d to four constant temperatures. No fish (20-40 mm) survived beyond 30 d at 32??C and the 30-d temperature lethal to 50% of the test animals was 30.6??C. Growth at static 28??C and 30??C was slower than growth at 25??C, suggesting that fish were stressed at sublethal temperatures. In ACE trials with diel temperature fluctuations of 4,6, and 10??C and a 32??C peak temperature, over 80% of fish (20-40 mm) survived 30 d. Although brief exposures to 32??C were not lethal, the growth of fish in the three fluctuating-temperature treatments was significantly less than the growth at the ambient temperature (25-29??C). To minimize thermal stress and buffer against temperature spikes, we recommend that loach minnow habitat be managed to avoid water temperatures above 28??C. ?? Copyright by the American Fisheries Society 2006.

  20. Retinal projections in the bowfin, Amia calva: cytoarchitectonic and experimental analysis.

    PubMed

    Butler, A B; Northcutt, R G

    1992-01-01

    The retinofugal projections in the bowfin, a non-teleost actinopterygian, were studied by autoradiographic and horseradish peroxidase methods, and the cytoarchitecture of retinorecipient regions of the diencephalon was analyzed with serially sectioned, Bodian stained material. Nuclei were identified in the thalamus, the periventricular portion of the posterior tuberculum, synencephalon, and pretectum which are homologous to like-named nuclei in teleosts and other non-teleost actinopterygian fishes. Of particular note, a posterior pretectal nucleus and, possibly, a homologue of nucleus corticalis were found to be present in the pretectum. These nuclei have previously been identified only in teleosts. The posterior pretectal nucleus is relatively small in the bowfin, and the distribution of a small, versus a large, posterior pretectal nucleus in Teleostei and Halecomorphi suggests that this nucleus was small plesiomorphically. The pattern of retinofugal projections in the bowfin is similar to that in other non-teleost actinopterygian fishes and in teleosts in most regards. Contralaterally, the retina projects to nuclei in the dorsal and ventral thalamus, superficial and central pretectum, dorsal and ventral accessory optic nuclei, and to the optic tectum. Additionally, there are sparse projections to the suprachiasmatic nucleus in the preoptic area, the periventricular nucleus of the posterior tuberculum, and the dorsal and ventral periventricular pretectal nuclei. Ipsilateral projections are sparse and are derived from fibers which do not decussate in the optic chiasm. Undecussated ipsilateral retinal projections, as present in the bowfin, are a widely distributed character in vertebrates and appear to be plesiomorphic for vertebrates.

  1. Co-invasion of a Red Sea fish and its ectoparasitic monogenean, Polylabris cf. mamaevi into the Mediterranean: observations on oncomiracidium behavior and infection levels in both seas.

    PubMed

    Pasternak, Zohar; Diamant, Ariel; Abelson, Avigdor

    2007-03-01

    This study investigated aspects of the biology of the monogenean gill ectoparasite Polylabris cf. mamaevi (Polyopisthocotylea: Microcotyleae) infecting rabbitfish, Siganus rivulatus (Forskal) (Teleostei: Siganidae). Both host and parasite are Lessepsian immigrants that have co-invaded the Mediterranean Sea via the Suez Canal. The infection prevalence and mean intensity of the polyopisthocotylean was examined in both native and immigrant host populations and found to be three times greater in the new biogeographical region. In vitro observations on parasite eggs from both areas indicated that hatching occurred almost exclusively in the dark. The reaction of the larval oncomiracidia to water flow and secreted host chemicals indicated that neither Red Sea nor Mediterranean oncomiracidia exposed to waterborne host metabolites displayed any significant response or change in behavior; however, upon encountering flow, they ceased to swim and drifted passively downstream. Host specificity of P. cf. mamaevi may have co-evolved with temporal synchronization of the parasite with the host's diurnal activity. Hatching of P. cf. mamaevi eggs was rhythmical and the timing coincided with the known nocturnal resting behavior of the hosts, when their schools lie immobile on the sea bottom. After hatching, abrupt cessation of active swimming by the oncomiracidia upon sensing host inhalant gill-ventilating currents is likely to facilitate rapid, passive entry into the gill chamber of a suitable host. The greater abundance of P. cf. mamaevi in the invading (Mediterranean) populations is probably due to the changed, new environment, possibly impacting host resistance to the parasite and encouraging heavier infections.

  2. Genomic analyses and cloning of novel chicken natriuretic peptide genes reveal new insights into natriuretic peptide evolution.

    PubMed

    Trajanovska, Sofie; Inoue, Koji; Takei, Yoshio; Donald, John A

    2007-11-01

    The natriuretic peptide (NP) family consists of multiple subtypes in teleosts, including atrial, B-type, ventricular, and C-type NPs (ANP, BNP, VNP, CNP-1-4, respectively), but only ANP, BNP, CNP-3, and CNP-4 have been identified in tetrapods. As part of understanding the molecular evolution of NPs in the tetrapod lineage, we identified NP genes in the chicken genome. Previously, only BNP and CNP-3 have been identified in birds, but we characterized two new chicken NP genes by cDNA cloning, synteny and phylogenetic analyses. One gene is an orthologue of CNP-1, which has only ever been reported in teleostei and bichir. The second gene could not be assigned to a particular NP subtype because of high sequence divergence and was named renal NP (RNP) due to its predominant expression in the kidney. CNP-1 mRNA was only detected in brain, while CNP-3 mRNA was expressed in kidney, heart, and brain. In the developing embryo, BNP and RNP transcripts were most abundant 24h post-fertilization, while CNP mRNA increased in a stage-dependent manner. Synthetic chicken RNP stimulated an increase in cGMP production above basal level in chicken kidney membrane preparations and caused a potent dose-dependent vasodilation of pre-constricted dorsal aortic rings. From conserved chromosomal synteny, we propose that the CNP-4 and ANP genes have been lost in chicken, and that RNP may have evolved from a VNP-like gene. Furthermore, we have demonstrated for the first time that CNP-1 is retained in the tetrapod lineage.

  3. Devario in Bangladesh: Species diversity, sibling species, and introgression within danionin cyprinids (Teleostei: Cyprinidae: Danioninae)

    PubMed Central

    Rahman, Md. Mizanur; Norén, Michael; Mollah, Abdur Rob

    2017-01-01

    Four species of Devario are recorded from Bangladesh: D. aequipinnatus, D. anomalus, D. coxi, new species, and D. devario. Devario aequipinnatus has a wide distribution in northern India and Bangladesh. Devario coxi, from southeastern Bangladesh near Cox’s Bazar, differs from D. aequipinnatus in mtDNA (COI, p-distance 1.8%), colouration, proportional measurements, and meristics. The minor morphological differences and low frequency of overlapping meristics suggest relatively recent separation of D. coxi from other D. aequipinnatus. Devario anomalus occurs only in southeastern Bangladesh and is here reported from localities in addition to the type locality. It differs from the similar D. xyrops in adjacent Myanmar by slender body shape and by 2.3% p-distance in the COI gene. Specimens of D. anomalus from the Sangu River were found to have the mitochondrial genome of D. aequipinnatus from Bangladesh, but agree with other D. anomalus in the nuclear RAG1 gene. Devario devario has a wide distribution on the Indian Peninsula and border regions; in Bangladesh it is restricted in distribution to the Ganga, Brahmaputra, and Meghna drainages. Reports of D. assamensis and D. malabaricus from Bangladesh are misidentifications. Perilampus ostreographus M’Clelland, 1839, is tentatively synonymized with D. aequipinnatus. Phylogenetic analysis of 14 species of striped devarios based on the COI gene results in a polytomy with four unresolved clades. Devario deruptotalea from the Chindwin basin is the sister group of D. aequipinnatus+D. coxi. Devario devario is the sistergroup of D. xyrops+D. anomalus. PMID:29166410

  4. Devario in Bangladesh: Species diversity, sibling species, and introgression within danionin cyprinids (Teleostei: Cyprinidae: Danioninae).

    PubMed

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

    2017-01-01

    Four species of Devario are recorded from Bangladesh: D. aequipinnatus, D. anomalus, D. coxi, new species, and D. devario. Devario aequipinnatus has a wide distribution in northern India and Bangladesh. Devario coxi, from southeastern Bangladesh near Cox's Bazar, differs from D. aequipinnatus in mtDNA (COI, p-distance 1.8%), colouration, proportional measurements, and meristics. The minor morphological differences and low frequency of overlapping meristics suggest relatively recent separation of D. coxi from other D. aequipinnatus. Devario anomalus occurs only in southeastern Bangladesh and is here reported from localities in addition to the type locality. It differs from the similar D. xyrops in adjacent Myanmar by slender body shape and by 2.3% p-distance in the COI gene. Specimens of D. anomalus from the Sangu River were found to have the mitochondrial genome of D. aequipinnatus from Bangladesh, but agree with other D. anomalus in the nuclear RAG1 gene. Devario devario has a wide distribution on the Indian Peninsula and border regions; in Bangladesh it is restricted in distribution to the Ganga, Brahmaputra, and Meghna drainages. Reports of D. assamensis and D. malabaricus from Bangladesh are misidentifications. Perilampus ostreographus M'Clelland, 1839, is tentatively synonymized with D. aequipinnatus. Phylogenetic analysis of 14 species of striped devarios based on the COI gene results in a polytomy with four unresolved clades. Devario deruptotalea from the Chindwin basin is the sister group of D. aequipinnatus+D. coxi. Devario devario is the sistergroup of D. xyrops+D. anomalus.

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

    PubMed

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

    2016-03-18

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

  6. 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. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Discovery and phylogenetic analysis of a riverine species flock of African electric fishes (Mormyridae: Teleostei).

    PubMed

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

    2002-03-01

    The evolution of species-specific mate recognition signals is of particular interest within speciose monophyletic groups with restricted distributions (known as "species flocks"). However, the explosive nature of speciation in these clades makes difficult the reconstruction of their phylogenetic history. Here we describe a species flock of riverine mormyrid fishes from west-central Africa in which electric signals may play a role in the reproductive isolation of sympatric species. In our recent field collections, totaling more than 1400 specimens from many localities, we recognize 38 forms that are distinct in their morphologies and electric organ discharge (EOD) characteristics. Of these 38, only four clearly correspond to described species. Here we treat these forms as operational taxonomic units (OTUs) in a phylogenetic analysis of cytochrome b sequence data from a sample of 86 specimens. We examined support in the molecular data for the monophyly of these 38 OTUs considered together, the monophyly of each phenotypically delimited OTU considered individually, and for relationships among OTUs congruent with those inferred from the distribution of morphological and EOD character states. Trees obtained by both maximum-parsimony and maximum-likelihood analyses, rooted with sequence data from outgroup taxa, provide evidence for the monophyly of these 38 OTUs with respect to other mormyrid fishes. The small genetic distances between many distinct forms suggest their recent divergence. However, in many instances the cytochrome b tree topology fails to support the monophyly of individual OTUs and close relationships between OTUs that are similar in morphology and EOD characteristics. In other cases, individuals from distinct OTUs share identical or nearly identical haplotypes. Close examination of these cases suggests that unnatural OTU definition is not the sole cause of this pattern, and we infer an incongruence between the mitochondrial gene tree and the organismal phylogeny caused by incomplete mitochondrial lineage sorting and/ or introgression across forms. The apparently rapid diversification in this clade of riverine electric fishes and the problems associated with recovering a meaningful species-level phylogeny from mitochondrial data parallel findings in other species flocks. Selection on EOD waveforms as mate recognition signals may be involved in the radiation of these fishes. This is the first description of a freshwater fish species flock from a riverine, as opposed to a lacustrine, environment.

  8. Patterns of oocyte development in natural habitat and captive Salminus hilarii Valenciennes, 1850 (Teleostei: Characidae).

    PubMed

    Honji, R M; Narcizo, A M; Borella, M I; Romagosa, E; Moreira, R G

    2009-03-01

    Fecundity and oocyte development in Salminus hilarii female brood stock were analyzed with the aim of investigating the impact of migration impediment on oogenesis. Histological analyses of the ovaries were performed in adult females caught in two different environments--the Tietê River (natural) and captivity--and the gonadossomatic index, oocyte diameter and fecundity determined. Five germ cell development stages (oogonium, perinucleolar, cortical alveoli, vitellogenic, ripe) and two other structures (postovulatory follicles and atretic oocytes) were observed in females caught in the river. Captive animals lacked the ripe oocytes and postovulatory follicles and had a relatively higher number of atretic oocytes. Females in captivity are known to produce larger oocytes, and they release fewer eggs in each spawn (absolute fecundity) when compared with animals that are able to migrate. Our results suggest that the Tietê River is undergoing alterations which are being reflected in the reproductive performance of S. hilarii, mainly due to the presence of atretic oocytes in females caught in the river. The lack of postovulatory follicles and ripe oocytes in captive animals reveals that migratory impediment negatively impacts final oocyte maturation. However, the stage of maturation reached is adequate for ovulation induction with hormone manipulation.

  9. 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.

  10. Squamous epithelium formation in the respiratory intestine of the bronze Corydoras Corydoras aeneus (Callichthyidae Teleostei).

    PubMed

    Satora, Leszek; Kozioł, Katarzyna; Zebrowski, Jacek

    2017-06-01

    Accessory respiratory organs in fish exhibit great diversity but share the presence of numerous capillaries covered by a simple squamous epithelium. The adoption of the intestine for respiratory function needs certain special modifications. In this study, we explored immunohistochemical and metabolic fingerprint features that could underlay this adaptation in bronze corydoras Corydoras aeneus. Immunohistochemical localization of the cytoplasmic domain of epidermal growth factor receptor (EGFR) in the respiratory part of intestine demonstrated a strong positive immunoreaction in epithelial cells and connective tissue. Fourier Transfer Infrared (FTIR) spectroscopy coupled with chemometrics discriminated between anterior and posterior region of intestine in terms of secondary structure of proteins and the abundance of p-cresol and other phenolics. The latter were reduced in the posterior part of intestine, indicating the cessation of digestive function in this region. It has been suggested that aquatic hypoxia via endocrine cells (hypoxia-sensitive) activate EGFR, which induce proliferation of squamous epithelial cells, thereby enabling gas diffusion in the posterior part of intestine. It seems that hypoxia and normoxia are opposed conditions adjusting the production of squamous epithelial cells in this intestine. The physiological role of EGFR in the respiratory intestine of bronze corydoras is of interest not only from an evolutionary aspect but also in terms of a potential model for observations process proliferation squamous epithelial cells. Future investigations on the molecular responses to different water oxygen levels in air-breathing bronze corydoras fish are required to clarify the mechanism responsible for squamous cell proliferation. Copyright © 2017 Elsevier GmbH. All rights reserved.

  11. 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.

  12. Morphological and molecular evidence for the occurrence of three Hippocampus species (Teleostei: Syngnathidae) in Brazil.

    PubMed

    Silveira, Rosana Beatriz; Siccha-Ramirez, Raquel; Silva, José Rodrigo Santos; Oliveira, Claudio

    2014-09-16

    For many decades only two species of seahorses were recognized from Brazil: Hippocampus reidi Ginsburg, 1933, the long snout seahorse, and H. erectus Perry, 1810, the lined seahorse. The presence of a possible third species, recognized in 2002, brought about the need for a broad revision of the genus in Brazilian waters. A total of 335 specimens of seahorses, obtained from Brazilian and other collections, representing the three putative species from Brazil were analyzed: H. reidi, the species of greatest abundance and occurs in estuaries and the sea; H. erectus, which occurs only in the sea, and Hippocampus patagonicus was also determined to be present based on multiple specimens. Our morphometric / numerical and molecular analysis showed that the species currently identified as H. erectus in Brazil is actually H. patagonicus Piacentino & Luzatto, 2004. The existence of a possible third species, was instead based on the true H. erectus, as confirmed in the present study by the study of classical systematic and mitochondrial analysis. Thus, we recognize three species of seahorses in Brazil: H. erectus, H. reidi and H. patagonicus.

  13. 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. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Pethia longicauda, a new species of barb (Teleostei: Cyprinidae) from the northern Western Ghats, India.

    PubMed

    Katwate, Unmesh; Paingankar, Mandar S; Raghavan, Rajeev; Dahanukar, Neelesh

    2014-08-01

    Pethia longicauda, a new cyprinid fish, is described from Hiranyakeshi River, Krishna drainage, Maharashtra, India. It can be distinguished from congeners based on a combination of characters including: a long caudal peduncle, incomplete lateral line, absence of barbels, upper lip thick and fleshy, distinct lateral fold on snout, 22-24 scales in lateral series, 5-6 lateral-line pored scales, nine predorsal scales, 9-10 prepelvic scales, 15-17 preanal scales, ½3/1/3½ transverse scales, 11-15 pairs of serrae on the distal half of the last unbranched dorsal-fin ray, 11-13 branched pectoral fin rays, 4+26 total vertebrae, 4+5 predorsal vertebrae, 4+13 abdominal and 13 caudal vertebrae, body iridescent silver in color with a black humeral spot, two black blotches on caudal peduncle and dorsal fin usually without any color bands or blotches but in breeding males with two rows of minute, indistinct black spots. 

  15. 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. © 2016 The Fisheries Society of the British Isles.

  16. Revision of the jawfish genus Lonchopisthus with description of a new Atlantic species (Teleostei: Opistognathidae)

    USGS Publications Warehouse

    Smith-Vaniz, William F.; Walsh, Stephen J.

    2017-01-01

    Synonymies, diagnoses, descriptions, illustrations, an identification key, and meristic frequency tables are provided for all species of Lonchopisthus. Most of the skeletal anatomy of L. higmani is also illustrated. A new jawfish, Lonchopisthus ancistrus n. sp., is described from the Gulf of Mexico and off Honduras based on 21 specimens 41–89 mm SL. The new species differs from other congeners by the following combination of characters: the posterior end of the maxilla strongly hooked; the membrane connecting the maxilla and premaxilla and the inner membrane covering the posterior part of the dentary pale; segmented dorsal-fin rays 11–13, with unbranched rays 2–5; longitudinal body-scale rows 33–39; and very long pelvic fins, 39.4–75.3% SL. Lonchopisthus lemur (and its synonym L. meadi) shares most characters with L. ancistrus, but differs in having shorter pelvic fins, 19.2–29.9% SL; fewer longitudinal body-scale rows, 26–33; and 5 infraorbitals (vs. 4). Both are relatively deep-water species, occurring from 100 m to at least 375 m (vs. 3–139 m in the other species). Lonchopisthus micrognathus is unique in having no branched caudal-fin rays at any size and the middle caudal-fin rays with free tips that may be used to maintain tactile contact with the substrate while hovering over its burrow. The western Atlantic Lonchopisthus higmani and eastern Pacific L. sinuscalifornicus are sister species that differ from the other Atlantic species in having the posterior end of the maxilla with a notch instead of a strong hook, the opercle with a large dark blotch, and one supraneural (vs. no supraneural).

  17. Tempo and rates of diversification in the South American cichlid genus Apistogramma (Teleostei: Perciformes: Cichlidae).

    PubMed

    Tougard, Christelle; García Dávila, Carmen R; Römer, Uwe; Duponchelle, Fabrice; Cerqueira, Frédérique; Paradis, Emmanuel; Guinand, Bruno; Angulo Chávez, Carlos; Salas, Vanessa; Quérouil, Sophie; Sirvas, Susana; Renno, Jean-François

    2017-01-01

    Evaluating biodiversity and understanding the processes involved in diversification are noticeable conservation issues in fishes subject to large, sometimes illegal, ornamental trade purposes. Here, the diversity and evolutionary history of the Neotropical dwarf cichlid genus Apistogramma from several South American countries are investigated. Mitochondrial and nuclear markers are used to infer phylogenetic relationships between 31 genetically identified species. The monophyly of Apistogramma is suggested, and Apistogramma species are distributed into four clades, corresponding to three morphological lineages. Divergence times estimated with the Yule process and an uncorrelated lognormal clock dated the Apistogramma origin to the beginning of the Eocene (≈ 50 Myr) suggesting that diversification might be related to marine incursions. Our molecular dating also suggests that the Quaternary glacial cycles coincide with the phases leading to Apistogramma speciation. These past events did not influence diversification rates in the speciose genus Apistogramma, since diversification appeared low and constant through time. Further characterization of processes involved in recent Apistogramma diversity will be necessary.

  18. Tempo and rates of diversification in the South American cichlid genus Apistogramma (Teleostei: Perciformes: Cichlidae)

    PubMed Central

    García Dávila, Carmen R.; Römer, Uwe; Duponchelle, Fabrice; Cerqueira, Frédérique; Paradis, Emmanuel; Guinand, Bruno; Angulo Chávez, Carlos; Salas, Vanessa; Quérouil, Sophie; Sirvas, Susana; Renno, Jean-François

    2017-01-01

    Evaluating biodiversity and understanding the processes involved in diversification are noticeable conservation issues in fishes subject to large, sometimes illegal, ornamental trade purposes. Here, the diversity and evolutionary history of the Neotropical dwarf cichlid genus Apistogramma from several South American countries are investigated. Mitochondrial and nuclear markers are used to infer phylogenetic relationships between 31 genetically identified species. The monophyly of Apistogramma is suggested, and Apistogramma species are distributed into four clades, corresponding to three morphological lineages. Divergence times estimated with the Yule process and an uncorrelated lognormal clock dated the Apistogramma origin to the beginning of the Eocene (≈ 50 Myr) suggesting that diversification might be related to marine incursions. Our molecular dating also suggests that the Quaternary glacial cycles coincide with the phases leading to Apistogramma speciation. These past events did not influence diversification rates in the speciose genus Apistogramma, since diversification appeared low and constant through time. Further characterization of processes involved in recent Apistogramma diversity will be necessary. PMID:28873089

  19. Parasites in sexual and asexual mollies (Poecilia, Poeciliidae, Teleostei): a case for the Red Queen?

    PubMed Central

    Tobler, Michael; Schlupp, Ingo

    2005-01-01

    The maintenance of sexual reproduction in the face of its supposed costs is a major paradox in evolutionary biology. The Red Queen hypothesis, which states that sex is an adaptation to fast-evolving parasites, is currently one of the most recognized explanations for the ubiquity of sex and predicts that asexual lineages should suffer from a higher parasite load if they coexist with closely related sexuals. We tested this prediction using four populations of the sexual fish species Poecilia latipinna and its asexual relative Poecilia formosa. Contrary to expectation, no differences in parasite load could be detected between the two species. PMID:17148156

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

    PubMed

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

    2002-11-01

    The black goby, Gobius niger, shows alternative male mating tactics, i.e., parental and sneaker males. Males release a sexual pheromone that attracts females and stimulates aggressive displays in males. This pheromone is produced by the mesorchial gland, a structure well developed in parental males but markedly undeveloped in sneakers. We measured the behavioral response of parental males to the ejaculates of males performing different reproductive tactics. Parental males reacted to the ejaculate of other parental males, with stereotypic aggressive behaviors, but not to the ejaculate of sneakers; consequently sneaker male ejaculate appears to be pheromonally inconspicuous. Copyright 2002 Wiley-Liss, Inc.

  1. 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.

  2. Morphology-based phylogeny of the suckermouth armored catfishes, with emphasis on the Neoplecostominae (Teleostei: Siluriformes: Loricariidae).

    PubMed

    Pereira, Edson H L; Reis, Roberto E

    2017-05-11

    A phylogenetic study of the Loricariidae with emphasis on the Neoplecostominae is presented based on a maximum parsimony analysis of 268 phenotypic characters encompassing osteology, arthrology, and external morphology. Results support previous hypotheses of the monophyly of the Neoplecostominae and each of the included genera: Hirtella, Isbrueckerichthys, Kronichthys, Neoplecostomus, Pareiorhaphis, and Pareiorhina. In addition, previously undiscovered diversity was revealed within the subfamily as an additional genus-level taxon, herein described as Euryochus. Relationships among neoplecostomine genera are: (Kronichthys (Euryochus ((Hirtella + Pareiorhaphis) (Pareiorhina (Isbrueckerichthys + Neoplecostomus))))). Additional undescribed diversity was also detected among most neoplecostomine genera and the Hypoptopomatinae. In addition, recently discovered genera Nannoplecostomus and Microplecostomus were included in the analysis, and were identified as sequential sister-taxa to Neoplecostominae + Hypoptopomatinae, which are currently not included in any subfamily and regarded as incertae sedis in Loricariidae. The three species of Lithogenes were included in an encompassing phylogenetic analysis for the first time, and were identified as a monophyletic unit and sister group to all remaining loricariids. The other loricariid subfamilies were also corroborated as monophyletic, and presented the following interrelationships (Lithogeninae (Delturinae (Loricariinae (Hypostominae (Nannoplecostomus (Microplecostomus (Hypoptopomatinae + Neoplecostominae). The Neoplecostominae and its genera are phylogenetically diagnosed, and hypothesized relationships are compared to those of previous morphological and molecular phylogenetic studies.

  3. Redescription of Alburnus kotschyi Steindachner, 1863, with comments on Alburnus sellal adanensis Battalgazi, 1944 (Teleostei: Leuciscidae).

    PubMed

    Freyhof, JÖrg; ÖzuluĞ, MÜfit; Kaya, CÜneyt; BayÇelebi, Esra; Turan, Davut

    2018-02-21

    Alburnus kotschyi is re-described and a neotype is designated. It is found in a small isolated coastal stream at Arsuz at the eastern Mediterranean coast as well as in the Ceyhan and Seyhan River drainages in southern Anatolia. Alburnus adanensis, from the Seyhan River, seems not to have been found again since its first description in 1944 and might be extinct.

  4. Two new species of Oxynoemacheilus from the Tigris drainage in Iraqi Kurdistan (Teleostei: Nemacheilidae).

    PubMed

    Freyhof, Jörg; Abdullah, Younis Sabir

    2017-03-02

    Two new species of Oxynoemacheilus are described from the Sirvan River drainage in Iraqi Kurdistan. Oxynoemacheilus gyndes, new species, is distinguished by having a very short lateral line, reaching behind the pectoral-fin base, no scales except on the posteriormost part of the caudal peduncle, a slightly emarginate caudal fin and no suborbital groove in males. Oxynoemacheilus hanae, new species, is distinguished by having a midlateral row of elongated blotches, isolated patches of dark-brown spots or blotches on lower flank, a deeply emarginate caudal fin and a suborbital groove in males.

  5. Environmental pollution affects molecular and biochemical responses during gonadal maturation of Astyanax fasciatus (Teleostei: Characiformes: Characidae).

    PubMed

    Tolussi, Carlos E; Gomes, Aline D Olio; Kumar, Anupama; Ribeiro, Cristiele S; Nostro, Fabiana L Lo; Bain, Peter A; de Souza, Gabriela B; Cuña, Rodrigo Da; Honji, Renato M; Moreira, Renata G

    2018-01-01

    Endocrine disrupting compounds (EDCs) have the potential to alter fish reproduction at various levels of organization. The aim of this study was to assess the impact of a natural environment with heavily anthropogenic influence on the physiological processes involved in reproduction in the freshwater fish lambari (Astyanax fasciatus) using different biomarkers. Adult males and females were collected in different seasons from two distinct sites in the same watershed: Ponte Nova Reservoir (PN) considered a pristine or small anthropogenic influence reference point; and Billings Reservoir (Bil), subjected to a large anthropogenic impact. Biological indices, such as hepatosomatic index and gonadosomatic index (GSI), gonadal histomorphology, fecundity, and biomarkers such as plasma levels of estradiol (E2) as well as hepatic gene expression of its alfa nuclear receptor (ERα), were analyzed. Hepatic vitellogenin (VTG) gene expression was evaluated in both sexes, as an indicator of xenoestrogen exposure. Females collected at PN presented a typical annual variation reflected in GSI, whereas for those sampled at Bil the index did not change through the seasons. The higher concentration of E2 in males collected at Bil during spring/2013, together with the detection of VTG gene expression, suggest the presence of EDCs in the water. These EDCs may have also influenced fecundity of females from Bil, which was higher during winter and spring/2013. Gene expression of ERα and ovarian morphology did not differ between fish from both sites. Water conditions from Bil reservoir impacted by anthropic activity clearly interfered mainly with biomarkers of biological effect such as plasma E2 levels and absolute and relative fecundity, but also altered biomarkers of exposure as VTG gene expression. These facts support the notion that waterborne EDCs are capable of causing estrogenic activity in A. fasciatus. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    PubMed

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

    2008-09-01

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

  7. Postglacial recolonization of eastern Blacknose Dace,Rhinichthys atratulus(Teleostei: Cyprinidae), through the gateway of New England

    PubMed Central

    Tipton, Michelle L; Gignoux-Wolfsohn, Sarah; Stonebraker, Phoebe; Chernoff, Barry

    2011-01-01

    During the last ice age, much of North America far south as 40°N was covered by glaciers (Hewitt 2000). About 20,000 years ago, as the glaciers retreated, the hydrologic landscape changed dramatically creating waterways for fish dispersal. The number of populations responsible for recolonization and the regions from which they recolonized are unknown for many freshwater fishes living in New England and southeastern Canada. The Blacknose Dace,Rhinichthys atratulus, is one of the freshwater fish species that recolonized this region. We hypothesize that the earliest deglaciated region, modern-day Connecticut, was recolonized byR. atratulusvia a single founding event by a single population. In this paper, we test this hypothesis phylogenetically with regard to the major drainage basins within Connecticut. The mitochondrial DNA exhibits low nucleotide diversity, high haplotype diversity, and a dominant haplotype found across the state. A small percentage of individuals in the Housatonic drainage basin, however, share a haplotype with populations in New York drainage basins, a haplotype not found elsewhere in Connecticut's drainage basins. We calculated a range for the rate of divergence for NADH dehydrogenase subunit 2 (nd2) and control region (ctr) of 4.43–6.76% and 3.84–8.48% per million years (my), respectively. While this range is higher than the commonly accepted rate of 2% for mitochondrial DNA, these results join a growing list of publications finding high rates of divergence for various taxa (Peterson and Masel 2009). The data support the conclusion that Connecticut as a whole was recolonized initially by a single founding event that came from a single refugium. Subsequently, the Housatonic basin alone experienced a secondary recolonization event. PMID:22393505

  8. Postglacial recolonization of eastern Blacknose Dace,Rhinichthys atratulus(Teleostei: Cyprinidae), through the gateway of New England.

    PubMed

    Tipton, Michelle L; Gignoux-Wolfsohn, Sarah; Stonebraker, Phoebe; Chernoff, Barry

    2011-11-01

    During the last ice age, much of North America far south as 40°N was covered by glaciers (Hewitt 2000). About 20,000 years ago, as the glaciers retreated, the hydrologic landscape changed dramatically creating waterways for fish dispersal. The number of populations responsible for recolonization and the regions from which they recolonized are unknown for many freshwater fishes living in New England and southeastern Canada. The Blacknose Dace,Rhinichthys atratulus, is one of the freshwater fish species that recolonized this region. We hypothesize that the earliest deglaciated region, modern-day Connecticut, was recolonized byR. atratulusvia a single founding event by a single population. In this paper, we test this hypothesis phylogenetically with regard to the major drainage basins within Connecticut. The mitochondrial DNA exhibits low nucleotide diversity, high haplotype diversity, and a dominant haplotype found across the state. A small percentage of individuals in the Housatonic drainage basin, however, share a haplotype with populations in New York drainage basins, a haplotype not found elsewhere in Connecticut's drainage basins. We calculated a range for the rate of divergence for NADH dehydrogenase subunit 2 (nd2) and control region (ctr) of 4.43-6.76% and 3.84-8.48% per million years (my), respectively. While this range is higher than the commonly accepted rate of 2% for mitochondrial DNA, these results join a growing list of publications finding high rates of divergence for various taxa (Peterson and Masel 2009). The data support the conclusion that Connecticut as a whole was recolonized initially by a single founding event that came from a single refugium. Subsequently, the Housatonic basin alone experienced a secondary recolonization event.

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

    PubMed

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

    2016-10-01

    We describe three new species of blood flukes (Aporocotylidae) and propose their classification within the genus Psettarium Goto & Ozaki, 1929. All three species were collected from the circulatory systems of pufferfishes caught off Bali, central Indonesia. Psettarium pulchellum n. sp. was found in the gills of both the narrow-lined puffer (Arothron manilensis de Procé) and the spiny blaasop (Tylerius spinosissimus Regan), while P. ogawai n. sp. and P. jimbaranense n. sp. were found in the gills of the reticulated puffer (Arothron reticularis Bloch & Schneider). The morphological characteristics of these taxa necessitated emendation of the diagnosis for the genus Psettarium, to accommodate the presence of an oral sucker, multiple or entirely post-caecal testes and a degenerate posterior testis. Features such as proportion of body length occupied by the oesophagus, and posterior caeca being ≥7× the length of anterior caeca, are no longer regarded as useful genus-level characters. Additionally, Sasala nolani is reassigned to this genus as Psettarium nolani n. comb. In phylogenetic analyses of the 28S and ITS2 rDNA regions, all three new taxa form a well-supported clade, together with Psettarium sinense and Psettarium nolani n. comb., the two other species of tetraodontid-infecting aporocotylids for which comparative rDNA data were available. The short branch lengths within this clade, despite dramatic morphological differences between the five species, suggest that rapid morphological diversification has occurred among the tetraodontid-infecting aporocotylids. The genus Psettarium has long been considered problematic. Further commentary is given on the history of this genus and how the issues presented might be resolved. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Comparative histology of the adult electric organ among four species of the genus Campylomormyrus (Teleostei: Mormyridae).

    PubMed

    Paul, Christiane; Mamonekene, Victor; Vater, Marianne; Feulner, Philine G D; Engelmann, Jacob; Tiedemann, Ralph; Kirschbaum, Frank

    2015-04-01

    The electric organ (EO) of weakly electric mormyrids consists of flat, disk-shaped electrocytes with distinct anterior and posterior faces. There are multiple species-characteristic patterns in the geometry of the electrocytes and their innervation. To further correlate electric organ discharge (EOD) with EO anatomy, we examined four species of the mormyrid genus Campylomormyrus possessing clearly distinct EODs. In C. compressirostris, C. numenius, and C. tshokwe, all of which display biphasic EODs, the posterior face of the electrocytes forms evaginations merging to a stalk system receiving the innervation. In C. tamandua that emits a triphasic EOD, the small stalks of the electrocyte penetrate the electrocyte anteriorly before merging on the anterior side to receive the innervation. Additional differences in electrocyte anatomy among the former three species with the same EO geometry could be associated with further characteristics of their EODs. Furthermore, in C. numenius, ontogenetic changes in EO anatomy correlate with profound changes in the EOD. In the juvenile the anterior face of the electrocyte is smooth, whereas in the adult it exhibits pronounced surface foldings. This anatomical difference, together with disparities in the degree of stalk furcation, probably contributes to the about 12 times longer EOD in the adult.

  11. Pleistocene to holocene expansion of the black-belt cichlid in Central America, Vieja maculicauda (Teleostei: Cichlidae)

    PubMed Central

    Ginger, Luke; Cage, Marcy; David, Kyle T.; Chakrabarty, Prosanta; Johnston, Mark; Matamoros, Wilfredo A.

    2017-01-01

    The distributions of many Northern Hemisphere organisms have been influenced by fluctuations in sea level and climatic conditions during Pleistocene interglacial periods. These cycles are associated with range contraction and refugia for northern-distributed organisms as a response to glaciers. However, lower sea levels in the tropics and sub-tropics created available habitat for expansion of the ranges of freshwater organisms. The goal of this study was to use ecological niche modeling to test the hypothesis of north to south range expansion of Vieja maculicauda associated with Pleistocene glacial cycles. Understanding the biogeography of this widespread species may help us better understand the geology and interconnectivity of Central American freshwaters. Occurrence data for V. maculicauda was based on georeferencing of all museum records of specimens recovered from FishNet2. General patterns of phylogeographic structure were assessed with mtDNA. Present day niche models were generated and subsequently projected onto paleoclimatic maps of the region during the Last Interglacial, Last Glacial Maximum, and mid-Holocene. Phylogenetic analysis of mtDNA sequence data showed no phylogeographic structure throughout the range of this widespread species. Present day niche models were congruent with the observed distribution of V. maculicauda in Central America. Results showed a lack of suitable freshwater habitat in northern Central America and Mexico during the Last Interglacial, with greatest range expansion during the Last Glacial Maximum and mid-Holocene. Results support the hypothesis of a north to south range expansion of V. maculicauda associated with glacial cycles. The wide distribution of this species compared to other closely related cichlids indicates the latter did not respond to the degree of V. maculicauda in expansion of their distributions. Future work aimed at comparisons with other species and modeling of future climatic scenarios will be a fruitful area of investigation. PMID:28558052

  12. 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

    2014-08-29

    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. 

  13. The European sea bass Dicentrarchus labrax genome puzzle: comparative BAC-mapping and low coverage shotgun sequencing

    PubMed Central

    2010-01-01

    Background Food supply from the ocean is constrained by the shortage of domesticated and selected fish. Development of genomic models of economically important fishes should assist with the removal of this bottleneck. European sea bass Dicentrarchus labrax L. (Moronidae, Perciformes, Teleostei) is one of the most important fishes in European marine aquaculture; growing genomic resources put it on its way to serve as an economic model. Results End sequencing of a sea bass genomic BAC-library enabled the comparative mapping of the sea bass genome using the three-spined stickleback Gasterosteus aculeatus genome as a reference. BAC-end sequences (102,690) were aligned to the stickleback genome. The number of mappable BACs was improved using a two-fold coverage WGS dataset of sea bass resulting in a comparative BAC-map covering 87% of stickleback chromosomes with 588 BAC-contigs. The minimum size of 83 contigs covering 50% of the reference was 1.2 Mbp; the largest BAC-contig comprised 8.86 Mbp. More than 22,000 BAC-clones aligned with both ends to the reference genome. Intra-chromosomal rearrangements between sea bass and stickleback were identified. Size distributions of mapped BACs were used to calculate that the genome of sea bass may be only 1.3 fold larger than the 460 Mbp stickleback genome. Conclusions The BAC map is used for sequencing single BACs or BAC-pools covering defined genomic entities by second generation sequencing technologies. Together with the WGS dataset it initiates a sea bass genome sequencing project. This will allow the quantification of polymorphisms through resequencing, which is important for selecting highly performing domesticated fish. PMID:20105308

  14. Physiological tolerances of juvenile robust redhorse, Moxostoma robustum: Conservation implications for an imperiled species

    USGS Publications Warehouse

    Walsh, S.J.; Haney, D.C.; Timmerman, C.M.; Dorazio, R.M.

    1998-01-01

    The robust redhorse, Moxostoma robustum (Teleostei: Catostomidae), is an imperiled sucker native to large rivers of the Atlantic slope of the southeastern United States. Juvenile M. robustum were tested for tolerances to temperature, salinity, pH, and hypoxia in order to evaluate basic early life-history requirements. Static (acute) tests resulted in estimates of mean lower temperature tolerances (5.3-19.4 ??C) that varied with prior thermal acclimation and indicated no apparent difference in tolerance among fish 30, 60, and 90 days old. Fish acclimated to 20 ??C and 30 ??C had significantly different mean critical thermal maxima (34.9 ??C and 37.2 ??C, respectively) and exhibited pronounced increased opercular ventilation rates with elevated temperatures. Fish exposed to acute and chronic increases in salinity showed unusual patterns of mortality above the isosmotic point (9 ppt) that reflected possible differences in body mass and prior acclimation conditions (i.e., water ionic composition); small fish and those held in soft water were the least tolerant of increased salinity. Abrupt exposure to extreme pH values resulted in greater than 50% mortality at pH values below 4.3 and above 9.5 within a 96-hour period. Fish exposed to progressive hypoxia utilized aquatic surface respiration at a mean oxygen concentration of 0.72-0.80 mg O2 l-1 (20 ??C and 30 ??C acclimated fish, respectively), and lost equilibrium at 0.54-.57 mg O2 l-1. Juvenile M. robustum are moderately tolerant of a wide range of ambient physicochemical parameters, but further research is needed to determine how both abiotic and biotic factors have contributed to population decline and extirpation of this species.

  15. Feeding habits of the bluemouth, Helicolenus dactylopterus dactylopterus (Delaroche, 1809) (Pisces: Sebastidae) in the Portuguese coast

    NASA Astrophysics Data System (ADS)

    Neves, Ana; Sequeira, Vera; Paiva, Rafaela Barros; Vieira, Ana Rita; Gordo, Leonel Serrano

    2012-06-01

    In order to investigate the feeding habits of Helicolenus dactylopterus dactylopterus along the continental Portuguese coast, a total of 619 individuals were sampled of which 60% contained food in their stomach and 35% had more than one prey item. Among the 81 prey items that were identified in the stomachs, benthic and benthopelagic prey prevail on this species diet. Acantephyra sp, Pasiphaea sp, mysidacea, and teleostei n.i. were the prey with the higher percent index of relative importance (%IRI) value. Three length groups (5-20 cm, 21-27 cm, and 28-48 cm) were defined through cluster analysis of the mean abundance of prey items. A permutational MANOVA detected significant differences in the diet and stomach fullness index for TLG, season, and maturation stage. Smaller fishes had a generalized diet, feeding mainly on mysidacea changing their diet above 20 cm TL, where a major consumption of natantia was found. The larger individuals, >28 cm TL, present a less generalized diet with pisces as dominant prey group. Seasonally, natantia and pisces were the principal prey groups during spring and winter, respectively, while mysidacea and other crustaceans were predominant during the rest of the year. Mysidacea were also the main prey group for immature individuals while natantia and pisces were the principal prey groups to the other maturity stages. The results of this study indicate that H. d. dactylopterus has a diverse diet focused on small crustaceans such as misyds and as specimens grow shrimps and fishes become more consumed, with larger specimens having a more specialized diet. The different nutritional needs during spawning season also seemed to influence the feeding habits of H. d. dactylopterus.

  16. Bipteria vetusta n. sp. – an old parasite in an old host: tracing the origin of myxosporean parasitism in vertebrates.

    PubMed

    Kodádková, Alena; Bartošová-Sojková, Pavla; Holzer, Astrid S; Fiala, Ivan

    2015-03-01

    Myxosporea (Myxozoa), a group of parasitic Cnidaria, use mostly bony fishes (Teleostei) as intermediate hosts; however, they can also parasitize other vertebrates such as cartilaginous fish (Chondrichthyes). Molecular data of myxosporeans from sharks and rays (Elasmobranchii) revealed these parasites to be one of the most basal representatives in the myxosporean phylogenetic tree, suggesting their ancient evolutionary history. A new myxosporean species, Bipteria vetusta n. sp., was found in the gall bladder of rabbit fish, Chimaera monstrosa (Holocephali; Chondrichthyes), and ssrDNA-based phylogeny revealed its basal position within the marine myxosporean lineage. Molecular dating based on ssrDNA analysis suggested the origin of a stem lineage leading to the marine myxosporean lineage at the time of the origin of Chondrichthyes in the Silurian era. The two common lineages of Myxozoa, Myxosporea and Malacosporea, were estimated to have split from their common ancestor in the Cambrian era. Tracing the history of evolution of the "vertebrate host type" character in the context of molecular dating showed that cartilaginous fish represented an ancestral state for all myxosporeans. Teleosts were very likely subsequently parasitized by myxozoans four times, independently. Myxosporean radiation and diversification appear to correlate with intermediate host evolution. The first intermediate hosts of myxosporeans were cartilaginous fish. When bony fish evolved and radiated, myxosporeans switched and adapted to bony fish, and subsequently greatly diversified in this new host niche. We believe that the present study is the first attempt at molecular dating of myxozoan evolution based on an old myxosporean species – a living myxosporean fossil. Copyright © 2015 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  17. Fish communities and related environmental conditions of the lower Boise River, southwestern Idaho, 1974-2004

    USGS Publications Warehouse

    MacCoy, Dorene E.

    2006-01-01

    Within the last century, the lower Boise River has been transformed from a meandering, braided, gravel-bed river that supported large runs of salmon to a channelized, regulated, urban river that provides flood control and irrigation water to more than 1,200 square miles of land. An understanding of the current status of the river's fish communities and related environmental conditions is important to support the ongoing management of the Boise River. Therefore, fish community data from the U.S. Geological Survey and the Idaho Department of Fish and Game collected since 1974 were analyzed to describe the status of fish communities in the lower Boise River. Each set of data was collected to address different study objectives, but is combined here to provide an overall distribution of fish in the lower Boise River over the last 30 years. Twenty-two species of fish in 7 families have been identified in the lower Boise River-3 salmonidae, trout and whitefish; 2 cottidae, sculpins; 3 catostomidae, suckers; 7 cyprinidae, minnows; 4 centrarchidae, sunfish; 2 ictaluridae, catfish; and 1 cobitidae, loach. Analysis of fish community data using an Index of Biotic Integrity (IBI) for Northwest rivers shows a decrease in the biotic integrity in a downstream direction, with the lowest IBI near the mouth of the Boise River. The number of tolerant and introduced fish were greater in the lower reaches of the river. Changes in land use, habitat, and water quality, as well as regulated streamflow have affected the lower Boise River fish community. IBI scores were negatively correlated with maximum instantaneous water temperature, specific conductance, and suspended sediment; as well as the basin land-use metrics, area of developed land, impervious surface area, and the number of major diversions upstream of a site. Fish communities in the upstream reaches were dominated by piscivorous fish, whereas the downstream reaches were dominated by tolerant, omnivorous fish. The percentage of

  18. Distribution of Hatschekia pagellibogneravei (Copepoda: Hatschekiidae) on the gills of Pagellus bogaraveo (Teleostei: Sparidae) from Madeira, Portugal.

    PubMed

    Hermida, Margarida; Cruz, Cristina; Saraiva, Aurélia

    2012-06-01

    A population of the gill parasite Hatschekia pagellibogneravei (Hesse, 1878) was studied on one of its sparid fish hosts, the blackspot seabream, Pagellus bogaraveo (Brünnich), off the coast of Madeira Island, Portugal, northeast Atlantic. Very high infection levels of this copepod were detected, with no significant seasonal differences. Abundance was negatively correlated with fish size. There were significant differences in the distribution of this copepod among the gill arches of the host, which seem to be best explained by differences in water flow within the gill habitat.

  19. Scaling mimesis: Morphometric and ecomorphological similarities in three sympatric plant-mimetic fish of the family Carangidae (Teleostei).

    PubMed

    Queiroz, Alexya Cunha de; Vallinoto, Marcelo; Sakai, Yoichi; Giarrizzo, Tommaso; Barros, Breno

    2018-01-01

    The mimetic juveniles of a number of carangid fish species resemble plant parts floating near the water surface, such as leaves, seeds and other plant debris. The present study is the first to verify the morphological similarities and ecomorphological relationships between three carangids (Oligoplites saurus, Oligoplites palometa and Trachinotus falcatus) and their associated plant models. Behavioral observations were conducted in the estuary of Curuçá River, in northeastern Pará (Brazil) between August 2015 and July 2016. Individual fishes and associated floating objects (models) were sampled for comparative analysis using both geometric and morphometric approaches. While the mimetic fish and their models retain their own distinct, intrinsic morphological features, a high degree of morphological similarity was found between each fish species and its model. The morphometric analyses revealed a general tendency of isometric development in all three fish species, probably related to their pelagic habitats, during all ontogenetic stages.

  20. Melanin concentrating hormone (MCH) is involved in the regulation of growth hormone in Cichlasoma dimerus (Cichlidae, Teleostei).

    PubMed

    Pérez Sirkin, D I; Cánepa, M M; Fossati, M; Fernandino, J I; Delgadin, T; Canosa, L F; Somoza, G M; Vissio, P G

    2012-03-01

    Growth hormone (GH) is the main pituitary hormone involved in somatic growth. In fish, the neuroendocrine control of GH is multifactorial due to the interaction of multiple inhibitors and stimulators. Melanin-concentrating hormone (MCH) is a cyclic peptide involved in skin color regulation of fish. In addition, MCH has been related to the regulation of food intake in both mammals and fish. There is only one report presenting evidences on the GH release stimulation by MCH in mammals in experiments in vitro, but there are no data on non-mammals. In the present work, we report for the first time the sequence of MCH and GH cDNA in Cichlasoma dimerus, a freshwater South American cichlid fish. We detected contacts between MCH fibers and GH cells in the proximal pars distalis region of the pituitary gland by double label confocal immunofluorescence indicating a possible functional relationship. Besides, we found that MCH increased GH transcript levels and stimulated GH release in pituitary cultures. Additionally, C. dimerus exposed to a white background had a greater number of MCH neurons with a larger nuclear area and higher levels of MCH transcript than those fish exposed to a black background. Furthermore, fish reared for 3 months in a white background showed a greater body weight and total length compared to those from black background suggesting that MCH might be related to somatic growth in C. dimerus. Our results report for the first time, that MCH is involved in the regulation of the synthesis and release of GH in vitro in C. dimerus, and probably in the fish growth rate. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. ZZ/ZW sex chromosome system in the endangered fish Lignobrycon myersi Miranda-Ribeiro, 1956 (Teleostei, Characiformes, Triportheidae).

    PubMed

    Rodrigues, Alexandre Dos Santos; Medrado, Aline Souza; Diniz, Débora; Oliveira, Claudio; Affonso, Paulo Roberto Antunes de Mello

    2016-01-01

    Lignobrycon myersi is an endemic fish species from a few coastal rivers in northeastern Brazil. Based on molecular evidence, Lignobrycon myersi and genera Triportheus Cope, 1872, Agoniates Müller & Troschel, 1845, Clupeacharax Pearson, 1924 and Engraulisoma Castro, 1981 were placed in the family Triportheidae. In the present work, we report the first cytogenetic data for Lignobrycon myersi to test the hypothesis that Lignobrycon and Triportheus are closely related. Studied specimens presented 2n=52 with 28 metacentric (m), 18 submetacentric (sm) and six subtelocentric (st) chromosomes for males and 27 m, 19 sm and 6 st for females, characterizing a ZZ/ZW sex chromosome system. The Z chromosome corresponds to the largest chromosome in karyotype while the W is about 50% smaller than the Z and largely heterochromatic. Terminal nucleolus organizer regions, GC-rich sites and 18S rDNA signals were detected on pair 14. However, additional 18S rDNA sites were observed in the W chromosome. The 5S rDNA was mainly detected on long arms of pair 7. The apparent synapomorphic chromosomal traits of Triportheus and Lignobrycon myersi reinforce their close phylogenetic relationship, suggesting that the ZZ/ZW chromosome system in both genera has arisen before cladogenic events.

  2. Ontogenic retinal changes in three ecologically distinct elopomorph fishes (Elopomorpha:Teleostei) correlate with light environment and behavior.

    PubMed

    Taylor, Scott M; Loew, Ellis R; Grace, Michael S

    2015-01-01

    Unlike the mammalian retina, the teleost fish retina undergoes persistent neurogenesis from intrinsic stem cells. In marine teleosts, most cone photoreceptor genesis occurs early in the embryonic and larval stages, and rods are added primarily during and after metamorphosis. This study demonstrates a developmental paradigm in elopomorph fishes in which retinas are rod-dominated in larvae, but undergo periods of later cone genesis. Retinal characteristics were compared at different developmental stages among three ecologically distinct elopomorph fishes-ladyfish (Elops saurus), bonefish (Albula vulpes), and speckled worm eel (Myrophis punctatus). The objectives were to improve our understanding of (1) the developmental strategy in the elopomorph retina, (2) the functional architecture of the retina as it relates to ecology, and (3) how the light environment influences photoreceptor genesis. Photoreceptor morphologies, distributions, and spectral absorption were studied at larval, juvenile, and adult stages. Premetamorphic retinas in all three species are rod-dominated, but the retinas of these species undergo dramatic change over the course of development, resulting in juvenile and adult retinal characteristics that correlate closely with ecology. Adult E. saurus has high rod densities, grouped photoreceptors, a reflective tapetum, and longer-wavelength photopigments, supporting vision in turbid, low-light conditions. Adult A. vulpes has high cone densities, low rod densities, and shorter-wavelength photopigments, supporting diurnal vision in shallow, clear water. M. punctatus loses cones during metamorphosis, develops new cones after settlement, and maintains high rod but low cone densities, supporting primarily nocturnal vision. M. punctatus secondary cone genesis occurs rapidly throughout the retina, suggesting a novel mechanism of vertebrate photoreceptor genesis. Finally, in postsettlement M. punctatus, the continuous presence or absence of visible light modulates rod distribution but does not affect secondary cone genesis, suggesting some degree of developmental plasticity influenced by the light environment.

  3. Oogenesis: From Oogonia to Ovulation in the Flagfish, Jordanella floridae Goode and Bean, 1879 (Teleostei: Cyprinodontidae).

    PubMed

    Uribe, Mari Carmen; Grier, Harry J; García-Alarcón, Adriana; Parenti, Lynne R

    2016-10-01

    We provide histological details of the development of oocytes in the cyprinodontid flagfish, Jordanella floridae. There are six stages of oogenesis: Oogonial proliferation, chromatin nucleolus, primary growth (previtellogenesis [PG]), secondary growth (vitellogenesis), oocyte maturation and ovulation. The ovarian lamellae are lined by a germinal epithelium composed of epithelial cells and scattered oogonia. During primary growth, the development of cortical alveoli and oil droplets, are initiated simultaneously. During secondary growth, yolk globules coalesce into a fluid mass. The full-grown oocyte contains a large globule of fluid yolk. The germinal vesicle is at the animal pole, and the cortical alveoli and oil droplets are located at the periphery. The disposition of oil droplets at the vegetal pole of the germinal vesicle during late secondary growth stage is a unique characteristic. The follicular cell layer is composed initially of a single layer of squamous cells during early PG which become columnar during early vitellogenesis. During primary and secondary growth stages, filaments develop among the follicular cells and also around the micropyle. The filaments are seen extending from the zona pellucida after ovulation. During ovulation, a space is evident between the oocyte and the zona pellucida. Asynchronous spawning activity is confirmed by the observation that, after ovulation, the ovarian lamellae contain follicles in both primary and secondary growth stages; in contrast, when the seasonal activity of oogenesis and spawning ends, after ovulation, the ovarian lamellae contain only follicles in the primary growth stage. J. Morphol. 277:1339-1354, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

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

    PubMed Central

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

    2017-01-01

    The first record of fossil teleostean otoliths from Antarctica is reported. The fossils were obtained from late Early Eocene shell beds of the La Meseta Formation, Seymour Island that represent the last temperate marine climate phase in Antarctica prior to the onset of cooling and subsequent glaciation during the late Eocene. A total of 17 otolith-based teleost taxa are recognized, with 10 being identifiable to species level containing nine new species and one new genus: Argentina antarctica sp. nov., Diaphus? marambionis sp. nov., Macruronus eastmani sp. nov., Coelorinchus balushkini sp. nov., Coelorinchus nordenskjoeldi sp. nov., Palimphemus seymourensis sp. nov., Hoplobrotula? antipoda sp. nov., Notoberyx cionei gen. et sp. nov. and Cepola anderssoni sp. nov. Macruronus eastmani sp. nov. is also known from the late Eocene of Southern Australia, and Tripterophycis immutatus Schwarzhans, widespread in the southern oceans during the Eocene, has been recorded from New Zealand, southern Australia, and now Antarctica. The otolith assemblage shows a typical composition of temperate fishes dominated by gadiforms, very similar at genus and family levels to associations known from middle Eocene strata of New Zealand and the late Eocene of southern Australia, but also to the temperate Northern Hemisphere associations from the Paleocene of Denmark. The Seymour Island fauna bridges a gap in the record of global temperate marine teleost faunas during the early Eocene climate maximum. The dominant gadiforms are interpreted as the main temperate faunal component, as in the Paleocene of Denmark. Here they are represented by the families Moridae, Merlucciidae (Macruroninae), Macrouridae and Gadidae. Nowadays Gadidae are a chiefly Northern Hemisphere temperate family. Moridae, Macruroninae and Macrouridae live today on the lower shelf to deep-water or mesopelagically with Macruroninae being restricted to the Southern Ocean. The extant endemic Antarctic gadiform family Muraenolepididae is missing, as are the dominant modern Antarctic fishes of the perciform suborder Notothenioidei. Recently, there has been much debate on isolated jaw bones of teleost fishes found in the La Meseta Formation and whether they would represent gadiforms (Merlucciidae in this case) or some early, primitive notothenioid. Otoliths are known to often complement rather than duplicate skeletal finds. With this in mind, we conclude that our otolith data support the presence of gadiforms in the early Eocene of Antarctica while it does not rule out the presence of notothenioids at the same time. http://zoobank.org/urn:lsid:zoobank.org:pub:A30E5364-0003-4467-B902-43A41AD456CC PMID:28077930

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

    PubMed

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

    2017-01-01

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

  6. A new species of sea urchin associating clingfish of the genus Dellichthys from New Zealand (Teleostei, Gobiesocidae)

    PubMed Central

    Conway, Kevin W.; Stewart, Andrew L.; Summers, Adam P.

    2018-01-01

    Abstract A new species of clingfish, Dellichthys trnskii sp. n. is described on the basis of 27 specimens, 11.9–46.0 mm SL, collected from intertidal and shallow coastal waters of New Zealand. It is distinguished from its only congener, D. morelandi Briggs, 1955 by characters of the cephalic sensory system and oral jaws, snout shape, and colouration in life. A rediagnosis is provided for D. morelandi, which is shown to exhibit sexual dimorphism in snout shape. PMID:29674890

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

    PubMed Central

    2009-01-01

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

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

    PubMed Central

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

    2016-01-01

    Abstract We use mitochondrial and nuclear sequence data to show that three weakly electric mormyrid fish specimens collected at three widely separated localities in Gabon, Africa over a 13-year period represent an unrecognized lineage within the subfamily Mormyrinae and determine its phylogenetic position with respect to other taxa. We describe these three specimens as a new genus containing two new species. Cryptomyrus, new genus, is readily distinguished from all other mormyrid genera by a combination of features of squamation, morphometrics, and dental attributes. Cryptomyrus ogoouensis, new species, is differentiated from its single congener, Cryptomyrus ona, new species, by the possession of an anal-fin origin located well in advance of the dorsal fin, a narrow caudal peduncle and caudal-fin lobes nearly as long as the peduncle. In Cryptomyrus ona, the anal-fin origin is located only slightly in advance of the dorsal fin, the caudal peduncle is deep and the caudal-fin lobes considerably shorter than the peduncle. Continued discovery of new taxa within the “Lower Guinea Clade” of Mormyridae highlights the incompleteness of our knowledge of fish diversity in West-Central Africa. We present a revised key to the mormyrid genera of Lower Guinea. PMID:27006619

  9. Aporocotyle michaudi n. sp. (Digenea: Aporocotylidae) from the emerald rock cod, Trematomus bernacchii (Teleostei: Perciformes) in Antarctica.

    PubMed

    Santoro, Mario; Cipriani, Paolo; Pankov, Plamen; Lawton, Scott P

    2015-10-01

    Aporocotyle michaudi n. sp. is described from the gill blood vessels of the emerald rock cod Trematomus bernacchii in the Ross Sea, Antarctica. It is distinguished from all other species of Aporocotyle by its body tegument showing single conical spines, spinous buccal capsule, and genital atrium positioned medially; all congeners described to date are characterized by clusters of tegumental spines, unspined buccal capsule and genital atrium located in the lateral part of the body. Aporocotyle michaudi n. sp. clearly differs from A. notothenia (the only other species of Aporocotyle found in a perciform fish) in its shape and arrangement of tegumental spines, buccal capsule features, location of genital atrium, body size, ratio of esophagus/body length, anterior caeca/posterior caeca ratio, number of testes, cirrus sac and ovary size and shape, and host. The new species is easily distinguished from A. argentinensis (the species that most closely resembles A. michaudi) by the shape and arrangement of tegumental spines, buccal capsule features, genital atrium location, left anterior caecum longer than right, esophagus/body length ratio, number of testes, cirrus sac size and shape, host and molecular analyses. Phylogenetic analyses of partial 28S rDNA genetic data showed that sequences representing the new species form a distinct clade with all other sequences for species of Aporocotyle and appear basal within the genus. Aporocotyle michaudi n. sp. represents the only species of genus described in Antarctica. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

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

    PubMed

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

    2016-09-26

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

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

    PubMed

    Leknes, I L

    2015-10-01

    The structure and histochemical properties of the intestine in bronze corydoras (Corydoras aeneus), a stomach-containing teleost, are described, with emphasis on goblet cells and mucin types. The proximal intestine displayed a normal structure for teleosts, whereas the distal intestine was wide, translucent, thin-walled, richly vascularized and constantly filled with air, suggesting an important respiratory role. Goblet cells were common throughout the entire intestine and displayed a variable, but mainly faint metachromatic colour after toluidine blue. They were moderately coloured by alcian blue at both pH 2.5 and 0.2 and displayed no colour after periodic acid followed by Schiff's solution (PAS), but a distinct purple-brown colour after high iron diamine followed by alcian blue (pH 2.5). Together, these results suggest that the mucin in the intestine goblet cells consists mainly of sulphated proteoglycans. Further, the results from the present lectin and neuraminidase tests suggest that these mucins contain much N-acetylglucoseamines and some N-acetylgalactosamines and sialic acid, but seem to lack glucose and mannose. They also contain some galactose-N-acetylgalactosamines sequences, normally hidden by sialic acid. The distinct brush border and mucus layer on the epithelial cells in the respiratory intestine may indicate some digestive roles, such as absorption of water, ions and simple carbohydrates. As sulphated proteoglycans are tough and attract much water, this mucus may play important roles in the protection against mechanical and chemical damages and in the defence against micro-organisms throughout the entire intestine, but in the respiratory intestine it may impede significantly the oxygen uptake. However, as this part of the intestine usually contains no digesta, but is completely filled with air, frequently renewed by dry air from the atmosphere, and the main function of the mucus may be to protect the respiratory epithelium against a destroying and dangerous desiccation. © 2014 Blackwell Verlag GmbH.

  12. Functional morphology of digestion in the stomachless, piscivorous needlefishes Tylosurus gavialoides and Strongylura leiura ferox (Teleostei: Beloniformes).

    PubMed

    Manjakasy, Jennifer M; Day, Ryan D; Kemp, Anne; Tibbetts, Ian R

    2009-10-01

    Belonidae are unusual in that they are carnivorous but lack a stomach and have a straight, short gut. To develop a functional morphological model for this unusual system the gut contents and alimentary tract morphology of Tylosurus gavialoides and Strongylura leiura ferox were investigated. The posterior orientation of the majority of the pharyngeal teeth supports the swallowing of whole large prey, but not their mastication. Mucogenic cells are abundant in the mucosa lining, particularly the esophagus, and their secretions are likely to protect the gut lining from damage while lubricating passage of the prey. Esophagus, anterior intestine, posterior intestine, and rectum all have highly reticulate mucosae. The anterior three gut sections are distensible to accommodate the passage of prey. However, following ingestion large prey are passed to the highly distensible posterior intestine where they rest head first against the ileorectal valve. Alimentary pH ranges from neutral to weakly acidic. Fish prey is digested head first with the head being largely digested while the remainder of the body is still intact. The nondistensibility of the rectum and the small aperture provided by the ileorectal valve suggest the products of intestinal digestion are either small particulates or fluids that pass into rectum where they are absorbed. 2009 Wiley-Liss, Inc.

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

    PubMed

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

    2012-02-01

    Liza bandialensis Diouf 1991 is redescribed because previous descriptions have not been in well-distributed publications and have lacked sufficient detail or reference to voucher specimens. The description provided here is based on specimens from the Sine Saloum estuary, Senegal (West Africa), from where the species was originally described. The distinctness of the species is confirmed both by meristic and molecular criteria. L. bandialensis presents a unique combination of characters with a low number of scales in the longitudinal series (32-33), 10.5-12 transverse scale rows, and distinctly yellowish dorsal, anal, and caudal fins. The currently known distribution of L. bandialensis includes coastal waters of Senegal, Gambia and Guinea Bissau. Finally, we provide a morphological identification key for the sixteen species of Mugilidae species occurring along the eastern central Atlantic coast of Africa. Copyright © 2011 Académie des sciences. All rights reserved.

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

    PubMed

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

    2007-08-01

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

  15. Evidence of birth-and-death evolution of 5S rRNA gene in Channa species (Teleostei, Perciformes).

    PubMed

    Barman, Anindya Sundar; Singh, Mamta; Singh, Rajeev Kumar; Lal, Kuldeep Kumar

    2016-12-01

    In higher eukaryotes, minor rDNA family codes for 5S rRNA that is arranged in tandem arrays and comprises of a highly conserved 120 bp long coding sequence with a variable non-transcribed spacer (NTS). Initially the 5S rDNA repeats are considered to be evolved by the process of concerted evolution. But some recent reports, including teleost fishes suggested that evolution of 5S rDNA repeat does not fit into the concerted evolution model and evolution of 5S rDNA family may be explained by a birth-and-death evolution model. In order to study the mode of evolution of 5S rDNA repeats in Perciformes fish species, nucleotide sequence and molecular organization of five species of genus Channa were analyzed in the present study. Molecular analyses revealed several variants of 5S rDNA repeats (four types of NTS) and networks created by a neighbor net algorithm for each type of sequences (I, II, III and IV) did not show a clear clustering in species specific manner. The stable secondary structure is predicted and upstream and downstream conserved regulatory elements were characterized. Sequence analyses also shown the presence of two putative pseudogenes in Channa marulius. Present study supported that 5S rDNA repeats in genus Channa were evolved under the process of birth-and-death.

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

    PubMed

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

    2016-10-17

    Thirty-six Paralichthys patagonicus and 30 Xystreurys rasile were collected in the state of Rio de Janeiro, Brazil to investigate the presence of anisakid and raphidascaridid nematodes. Anisakis typica, Terranova sp., Contracaecum sp., Hysterothylacium deardorffoverstreetorum, and Raphidascaris sp. were identified using integrative taxonomy of morphological and genetic data. Morphological and morphometric analysis was conducted using bright field microscopy with scanning electron microscopy for topographic characterization of the cuticular surface. Phylogenetic analysis, using ITS and cox2 molecular targets, clearly demonstrated the species identification of A. typica and H. deardorffoverstreetorum and the high diversity of H. deardorffoverstreetorum. This is the first report of A. typica, H. deardorffoverstreetorum, and Raphidascaris sp. parasitizing P. patagonicus and X. rasile. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Four new species of coral gobies (Teleostei: Gobiidae: Gobiodon), with comments on their relationships within the genus

    PubMed Central

    Bogorodsky, Sergey V.; Suzuki, Toshiyuki

    2013-01-01

    Four new species of the coral-associated gobiid genus Gobiodon were discovered in the Red Sea. Although several of these species are common not only in the Red Sea but also in the Indian and western Pacific Ocean, they have not been described before. Detailed descriptions of the four species are based on morphological and molecular genetic (mitochondrial 12s and 16s rRNA) investigations. The new species, like most species of the genus, lack scales and have species-specific life colouration. Gobiodon bilineatus sp. nov. is the closest relative to G. quinquestrigatus (Valenciennes) and of G. sp. D (Munday et al.), and has five distinct, blue lines on the head as juveniles and subadults, which disappear in adults, and which are often uniformly orange-red with two distinct, vertical blue lines through each eye. Gobiodon irregularis sp. nov. has been confused with the former new species in the past, and is closely related to G. oculolineatus Wu, but is unmistakable in live colouration. Juveniles are characterised by a transparent body, red bars on the head with bluish to greyish interspaces, and irregular red lines and dots on the nape and dorsally on the body. Adults are usually uniformly brown or green-brown, with only remnants of the bars through the eye and below the orbit. Gobiodon ater sp. nov. is a small, entirely black species and can be easily confused with other black species, although it is genetically clearly distinct from G. ceramensis Bleeker and its black relatives. Gobiodon fuscoruber sp. nov. is likely to be the closest relative of G. ater sp. nov., but is uniformly reddish-brown or brown, has bright median fin margins (at least in the Red Sea), and grows considerably larger than G. ater. It has been genetically determined that G. fuscoruber sp. nov. is identical with an Indian Ocean/western Pacific species that has been called G. unicolor Castelnau by several authors. However, examination of the holotype of G. unicolor, including the original description, revealed that the type species and original description are clearly different from the species frequently called G. unicolor. The holotype resembles G. histrio (Valenciennes) and the name G. unicolor must therefore be considered a junior synonym of G. histrio. As a consequence, a new name for this species is provided. PMID:24511221

  18. Scaling mimesis: Morphometric and ecomorphological similarities in three sympatric plant-mimetic fish of the family Carangidae (Teleostei)

    PubMed Central

    de Queiroz, Alexya Cunha; Vallinoto, Marcelo; Sakai, Yoichi; Giarrizzo, Tommaso

    2018-01-01

    The mimetic juveniles of a number of carangid fish species resemble plant parts floating near the water surface, such as leaves, seeds and other plant debris. The present study is the first to verify the morphological similarities and ecomorphological relationships between three carangids (Oligoplites saurus, Oligoplites palometa and Trachinotus falcatus) and their associated plant models. Behavioral observations were conducted in the estuary of Curuçá River, in northeastern Pará (Brazil) between August 2015 and July 2016. Individual fishes and associated floating objects (models) were sampled for comparative analysis using both geometric and morphometric approaches. While the mimetic fish and their models retain their own distinct, intrinsic morphological features, a high degree of morphological similarity was found between each fish species and its model. The morphometric analyses revealed a general tendency of isometric development in all three fish species, probably related to their pelagic habitats, during all ontogenetic stages. PMID:29558476

  19. Phylogenetic relationships and timing of diversification in gonorynchiform fishes inferred using nuclear gene DNA sequences (Teleostei: Ostariophysi).

    PubMed

    Near, Thomas J; Dornburg, Alex; Friedman, Matt

    2014-11-01

    The Gonorynchiformes are the sister lineage of the species-rich Otophysi and provide important insights into the diversification of ostariophysan fishes. Phylogenies of gonorynchiforms inferred using morphological characters and mtDNA gene sequences provide differing resolutions with regard to the sister lineage of all other gonorynchiforms (Chanos vs. Gonorynchus) and support for monophyly of the two miniaturized lineages Cromeria and Grasseichthys. In this study the phylogeny and divergence times of gonorynchiforms are investigated with DNA sequences sampled from nine nuclear genes and a published morphological character matrix. Bayesian phylogenetic analyses reveal substantial congruence among individual gene trees with inferences from eight genes placing Gonorynchus as the sister lineage to all other gonorynchiforms. Seven gene trees resolve Cromeria and Grasseichthys as a clade, supporting previous inferences using morphological characters. Phylogenies resulting from either concatenating the nuclear genes, performing a multispecies coalescent species tree analysis, or combining the morphological and nuclear gene DNA sequences resolve Gonorynchus as the living sister lineage of all other gonorynchiforms, strongly support the monophyly of Cromeria and Grasseichthys, and resolve a clade containing Parakneria, Cromeria, and Grasseichthys. The morphological dataset, which includes 13 gonorynchiform fossil taxa that range in age from Early Cretaceous to Eocene, was analyzed in combination with DNA sequences from the nine nuclear genes and a relaxed molecular clock to estimate times of evolutionary divergence. This "tip dating" strategy accommodates uncertainty in the phylogenetic resolution of fossil taxa that provide calibration information in the relaxed molecular clock analysis. The estimated age of the most recent common ancestor (MRCA) of living gonorynchiforms is slightly older than estimates from previous node dating efforts, but the molecular tip dating estimated ages of Kneriinae (Kneria, Parakneria, Cromeria, and Grasseichthys) and the two paedomorphic lineages, Cromeria and Grasseichthys, are considerably younger. Copyright © 2014 Elsevier Inc. All rights reserved.

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

    PubMed

    Turgeon, J; Bernatchez, L

    2001-11-11

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

  1. Dysomma alticorpus, a new species of cutthroat eel from the Gulf of Aqaba, Red Sea (Teleostei: Synaphobranchidae).

    PubMed

    Fricke, Ronald; Golani, Daniel; Appelbaum-Golani, Brenda; Zajonz, Uwe

    2018-02-01

    The cutthroat eel Dysomma alticorpus n. sp. is described based on a single specimen collected in a trammel net at a depth of 350m off Eilat, Israel, Gulf of Aqaba, Red Sea. The new species belongs to the Dysomma anguillare species complex, which comprises species possessing a well-developed pectoral fin, intermaxillary teeth, a uniserial row of 7-15 large compound teeth in the lower jaw (which may be followed by a few smaller teeth), and an anteriorly situated anus with the trunk shorter than the head length. It is characterised by a combination of the following characters: origin of the dorsal fin well anterior to the base of the pectoral fin, predorsal length 13.8% TL; preanal length 22.8% TL; three compound teeth on the vomer; head pores: IO 4, SO 3; M 6; POP 0; AD 1, F 0, ST 0; lateral-line pores: predorsal 4, prepectoral 8, preanal 14, total 57-58, the last at the posterior two-thirds of the total length; MVF 7-16-115; total vertebrae 115. Dysomma alticorpus n. sp. is compared with other species of the genus. A revised key to the species of the genera Dysomma and Dysommina is provided. Copyright © 2018 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

  2. Dynamics of tandemly repeated DNA sequences during evolution of diploid and tetraploid botiid loaches (Teleostei: Cobitoidea: Botiidae)

    PubMed Central

    Bohlen, Jörg; Šlechtová, Vendula; Altmanová, Marie; Pelikánová, Šárka; Ráb, Petr

    2018-01-01

    Polyploidization has played an important role in the evolution of vertebrates, particularly at the base of Teleostei–an enormously successful ray-finned fish group with additional genome doublings on lower taxonomic levels. The investigation of post-polyploid genome dynamics might provide important clues about the evolution and ecology of respective species and can help to decipher the role of polyploidy per se on speciation. Few studies have attempted to investigate the dynamics of repetitive DNA sequences in the post-polyploid genome using molecular cytogenetic tools in fishes, though recent efforts demonstrated their usefulness. The demonstrably monophyletic freshwater loach family Botiidae, branching to evolutionary diploid and tetraploid lineages separated >25 Mya, offers a suited model group for comparing the long-term repetitive DNA evolution. For this, we integrated phylogenetic analyses with cytogenetical survey involving Giemsa- and Chromomycin A3 (CMA3)/DAPI stainings and fluorescence in situ hybridization with 5S/45S rDNA, U2 snDNA and telomeric probes in representative sample of 12 botiid species. The karyotypes of all diploids were composed of 2n = 50 chromosomes, while majority of tetraploids had 2n = 4x = 100, with only subtle interspecific karyotype differences. The exceptional karyotype of Botia dario (2n = 4x = 96) suggested centric fusions behind the 2n reduction. Variable patterns of FISH signals revealed cases of intraspecific polymorphisms, rDNA amplification, variable degree of correspondence with CMA3+ sites and almost no phylogenetic signal. In tetraploids, either additivity or loci gain/loss was recorded. Despite absence of classical interstitial telomeric sites, large blocks of interspersed rDNA/telomeric regions were found in diploids only. We uncovered different molecular drives of studied repetitive DNA classes within botiid genomes as well as the advanced stage of the re-diploidization process in tetraploids. Our results may contribute to link genomic approach with molecular cytogenetic analyses in addressing the origin and mechanism of this polyploidization event. PMID:29590207

  3. Buccal venom gland associates with increased of diversification rate in the fang blenny fish Meiacanthus (Blenniidae; Teleostei).

    PubMed

    Liu, Shang-Yin Vanson; Frédérich, Bruno; Lavoué, Sébastien; Chang, Jonathan; Erdmann, Mark V; Mahardika, Gusti Ngurah; Barber, Paul H

    2018-08-01

    At the macroevolutionary level, many mechanisms have been proposed to explain explosive species diversification. Among them morphological and/or physiological novelty is considered to have a great impact on the tempo and the mode of diversification. Meiacanthus is a genus of Blenniidae possessing a unique buccal venom gland at the base of an elongated canine tooth. This unusual trait has been hypothesized to aid escape from predation and thus potentially play an important role in their pattern of diversification. Here, we produce the first time-calibrated phylogeny of Blenniidae and we test the impact of two morphological novelties on their diversification, i.e. the presence of swim bladder and buccal venom gland, using various comparative methods. We found an increase in the tempo of lineage diversification at the root of the Meiacanthus clade, associated with the evolution of the buccal venom gland, but not the swim bladder. Neither morphological novelty was associated with the pattern of size disparification in blennies. Our results support the hypothesis that the buccal venom gland has contributed to the explosive diversification of Meiacanthus, but further analyses are needed to fully understand the factors sustaining this burst of speciation. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Histochemical localisation of carbonic anhydrase in the inner ear of developing cichlid fish, Oreochromis mossambicus

    NASA Astrophysics Data System (ADS)

    Beier, M.; Hilbig, R.; Anken, R.

    2008-12-01

    Inner ear otolith growth in terms of mineralisation mainly depends on the enzyme carbonic anhydrase (CAH). CAH is located in specialised, mitochondria-rich macular cells (ionocytes), which are involved in the endolymphatic ion exchange, and the enzyme is responsible for the provision of the pH-value necessary for otolithic calcium carbonate deposition. In the present study, for the first time the localisation of histochemically demonstrated CAH was analysed during the early larval development of a teleost, the cichlid fish Oreochromis mossambicus. CAH-reactivity was observed already in stage 7 animals (onset of otocyst development; staging follows Anken et al. [Anken, R., Kappel, T., Slenzka, K., Rahmann, H. The early morphogenetic development of the cichlid fish, Oreochromis mossambicus (Perciformes, Teleostei). Zool. Anz. 231, 1-10, 1993]). Neuroblasts (from which sensory and supporting cells are derived) proved to be CAH-positive. Already at stage 12 (hatch), CAH-positive regions could be attributed to ionocyte containing regions both in the so-called meshwork and patches area of the macula (i.e., clearly before ionocytes can be identified on ultrastructural level or by employing immunocytochemistry). In contrast to the circumstances observed in mammalian species, sensory hair cells stained negative for CAH in the cichlid. With the onset of stage 16 (finray primordia in dorsal fin, yolk-sac being increasingly absorbed), CAH-reactivity was observed in the vestibular nerve. This indicates the onset of myelinisation and thus commencement of operation. The localisation of CAH in the inner ear of fish (especially the differences in comparison to mammals) is discussed on the basis of its role in otolith calcification. Since the vestibular system is a detector of acceleration and thus gravity, also aspects regarding effects of altered gravity on CAH and hence on the mineralisation of otoliths in an adaptive process are addressed.

  5. Different processes lead to similar patterns: a test of codivergence and the role of sea level and climate changes in shaping a southern temperate freshwater assemblage

    PubMed Central

    2011-01-01

    Background Understanding how freshwater assemblages have been formed and maintained is a fundamental goal in evolutionary and ecological disciplines. Here we use a historical approach to test the hypothesis of codivergence in three clades of the Chilean freshwater species assemblage. Molecular studies of freshwater crabs (Aegla: Aeglidae: Anomura) and catfish (Trichomycterus arealatus: Trichomycteridae: Teleostei) exhibited similar levels of genetic divergences of mitochondrial lineages between species of crabs and phylogroups of the catfish, suggesting a shared evolutionary history among the three clades in this species assemblage. Results A phylogeny was constructed for Trichomycterus areolatus under the following best-fit molecular models of evolution GTR + I + R, HKY + I, and HKY for cytochrome b, growth hormone, and rag 1 respectively. A GTR + I + R model provided the best fit for both 28S and mitochondrial loci and was used to construct both Aegla phylogenies. Three different diversification models were observed and the three groups arose during different time periods, from 2.25 to 5.05 million years ago (Ma). Cladogenesis within Trichomycterus areolatus was initiated roughly 2.25 Ma (Late Pliocene - Early Pleistocene) some 1.7 - 2.8 million years after the basal divergences observed in both Aegla clades. These results reject the hypothesis of codivergence. Conclusions The similar genetic distances between terminal sister-lineages observed in these select taxa from the freshwater Chilean species assemblage were formed by different processes occurring over the last ~5.0 Ma. Dramatic changes in historic sea levels documented in the region appear to have independently shaped the evolutionary history of each group. Our study illustrates the important role that history plays in shaping a species assemblage and argues against assuming similar patterns equal a shared evolutionary history. PMID:22118288

  6. Purification and characterization of zebrafish hatching enzyme - an evolutionary aspect of the mechanism of egg envelope digestion.

    PubMed

    Sano, Kaori; Inohaya, Keiji; Kawaguchi, Mari; Yoshizaki, Norio; Iuchi, Ichiro; Yasumasu, Shigeki

    2008-12-01

    There are two hatching enzyme homologues in the zebrafish genome: zebrafish hatching enzyme ZHE1 and ZHE2. Northern blot and RT-PCR analysis revealed that ZHE1 was mainly expressed in pre-hatching embryos, whereas ZHE2 was rarely expressed. This was consistent with the results obtained in an experiment conducted at the protein level, which demonstrated that one kind of hatching enzyme, ZHE1, was able to be purified from the hatching liquid. Therefore, the hatching of zebrafish embryo is performed by a single enzyme, different from the finding that the medaka hatching enzyme is an enzyme system composed of two enzymes, medaka high choriolytic enzyme (MHCE) and medaka low choriolytic enzyme (MLCE), which cooperatively digest the egg envelope. The six ZHE1-cleaving sites were located in the N-terminal regions of egg envelope subunit proteins, ZP2 and ZP3, but not in the internal regions, such as the ZP domains. The digestion manner of ZHE1 appears to be highly analogous to that of MHCE, which partially digests the egg envelope and swells the envelope. The cross-species digestion using enzymes and substrates of zebrafish and medaka revealed that both ZHE1 and MHCE cleaved the same sites of the egg envelope proteins of two species, suggesting that the substrate specificity of ZHE1 is quite similar to that of MHCE. However, MLCE did not show such similarity. Because HCE and LCE are the result of gene duplication in the evolutionary pathway of Teleostei, the present study suggests that ZHE1 and MHCE maintain the character of an ancestral hatching enzyme, and that MLCE acquires a new function, such as promoting the complete digestion of the egg envelope swollen by MHCE.

  7. Plate-like permanent dental laminae of upper jaw dentition in adult gobiid fish, Sicyopterus japonicus.

    PubMed

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

    2010-04-01

    Sicyopterus japonicus (Teleostei, Gobiidae) possesses a unique upper jaw dentition different from that known for any other teleosts. In the adults, many (up to 30) replacement teeth, from initiation to attachment, are arranged orderly in a semicircular-like strand within a capsule of connective tissue on the labial side of each premaxillary bone. We have applied histological, ultrastructural, and three-dimensional imaging from serial sections to obtain insights into the distribution and morphological features of the dental lamina in the upper jaw dentition of adult S. japonicus. The adult fish has numerous permanent dental laminae, each of which is an infolding of the oral epithelium at the labial side of the functional tooth and forms a thin plate-like structure with a wavy contour. All replacement teeth of a semicircular-like strand are connected to the plate-like dental lamina by the outer dental epithelium and form a tooth family; neighboring tooth families are completely separated from each other. The new tooth germ directly buds off from the ventro-labial margin of the dental lamina, whereas no distinct free end of the dental lamina is present, even adjacent to this region. Cell proliferation concentrated at the ventro-labial margin of the dental lamina suggests that this region is the site for repeated tooth initiation. During tooth development, the replacement tooth migrates along a semicircular-like strand and eventually erupts through the dental lamina into the oral epithelium at the labial side of the functional tooth. This unique thin plate-like permanent dental lamina and the semicircular-like strand of replacement teeth in the upper jaw dentition of adult S. japonicus probably evolved as a dental adaptation related to the rapid replacement of teeth dictated by the specialized feeding habit of this algae-scraping fish.

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

    PubMed

    Cruz Escalona, V H; Abitia Cárdenas, L A

    2004-03-01

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

  9. A review of the Callogobius (Teleostei: Gobiidae) from the Red Sea with the description of a new species.

    PubMed

    Delventhal, Naomi R; Mooi, Randall D; Bogorodsky, Sergey V; Mal, Ahmad O

    2016-10-31

    Five species of Callogobius Bleeker have been previously reported from the Red Sea: C. amikami Goren, Miroz & Baranes, C. clarki (Goren), C. dori Goren, C. flavobrunneus (Smith), and C. maculipinnis (Fowler). Records of C. bifasciatus (Smith) in the Red Sea are referable to C. clarki. Callogobius amikami has been previously known only from a single specimen, the holotype from the Red Sea, and two photographs, a live juvenile from Oman and a live specimen at an aquarium at Coral World, Eilat. We obtained a possible additional juvenile from the Red Sea, although we are unable to definitively determine its identity. Red Sea specimens previously identified as C. maculipinnis [or C. irrasus (Smith)] represent a new species, distinguished from the latter by normally having four sets of transverse mandibular rows on each side (rather than three); this species is described here as Callogobius pilosimentum sp. nov. Four specimens of an additional, undescribed species of Callogobius, C. sp. A, have been collected from the Red Sea, but we withhold a formal description because this species is currently under study by colleagues. Callogobius sclateri (Steindachner), previously known from the Indo-West Pacific, is reported from the Red Sea for the first time. A key to all seven species is provided. Each species is photographed, habitat is described and a brief description with detailed comparisons is provided. The new species and C. clarki are endemic to the Red Sea.

  10. Short-term effects of triiodothyronine on the bowfin, Amia calva (Holostei), and the lake char, Salvelinus namaycush (Teleostei).

    PubMed

    Ballantyne, J S; John, T M; Singer, T D; Oommen, O V

    1992-01-01

    To assess the role of triiodothyronine (T3) in mediating short-term changes in metabolism, such as those occurring in circadian patterns, we examined the effects of intraperitoneal injection of T3 on the oxidation of substrates by isolated mitochondria from liver of the bowfin, Amia calva, and red muscle and liver of the lake char, Salvelinus namaycush. Selected enzymes were measured in red muscle and liver of the lake char. Three hours after intraperitoneal injection of T3, oxidation of some substrates by mitochondria isolated from the liver of the bowfin was reduced. Similar treatment had no effect on substrate oxidation in liver mitochondria isolated from lake char. Oxidation of substrates by lake char red muscle mitochondria was stimulated by T3 injection. Citrate synthase levels were increased in red muscle suggesting that changes in enzyme activity may be in part responsible for the short-term mitochondrial responses to T3 injection.

  11. Immunohistochemical, morphological and histometrical analyses of follicular development in Astyanax bimaculatus (Teleostei: Characidae) exposed to an organochlorine insecticide.

    PubMed

    Marcon, Lucas; Thomé, Ralph Gruppi; Mounteer, Ann Honor; Bazzoli, Nilo; Rizzo, Elizete; Benjamin, Laércio Dos Anjos

    2017-09-01

    Thiodan ® is an organochlorine insecticide used in agriculture that can reach aquatic ecosystems where it can affect fish reproduction. This research aimed to evaluate follicular development and the expression of integrin β1, collagen type IV and caspase 3 by morphological, histometrical and immunohistochemical analyses of Astyanax bimaculatus exposed to Thiodan ® . Treatments included three sublethal concentrations of Thiodan ® (1.15, 2.30, and 5.60μgL -1 ) for 96h and a control without the insecticide. Mature females with ovaries in advanced follicular development were chosen for study (average weight: 11.52 ± 2.0g; average total length: 9.12 ± 0.64cm). The follicles of A. bimaculatus exhibited normal morphology, while the diameters of secondary follicles showed an increase (P< 0.05) in all concentrations when compared to the control group; a characteristic of follicles undergoing the initial stages of intoxication. Immunohistochemical analysis revealed secondary follicles with greater expression of integrin β1 and collagen type IV in cytoplasm of follicular cells than in the primary follicles in all treatments and in the control. Immunolocalization of caspase 3 was detected in follicular cells during secondary development in all tested concentrations of Thiodan ® and the control. These analyses demonstrate positive immunolocalization throughout the course of follicular development, even in fish exposed to varying concentrations of Thiodan ® for 96h, demonstrating that follicular cells retain their physiological integrity. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. B chromosome dynamics in Prochilodus costatus (Teleostei, Characiformes) and comparisons with supernumerary chromosome system in other Prochilodus species

    PubMed Central

    Melo, Silvana; Utsunomia, Ricardo; Penitente, Manolo; Sobrinho-Scudeler, Patrícia Elda; Porto-Foresti, Fábio; Oliveira, Claudio; Foresti, Fausto; Dergam, Jorge Abdala

    2017-01-01

    Abstract Within the genus Prochilodus Agassiz, 1829, five species are known to carry B chromosomes, i.e. chromosomes beyond the usual diploid number that have been traditionally considered as accessory for the genome. Chromosome microdissection and mapping of repetitive DNA sequences are effective tools to assess the DNA content and allow a better understanding about the origin and composition of these elements in an array of species. In this study, a novel characterization of B chromosomes in Prochilodus costatus Valenciennes, 1850 (2n=54) was reported for the first time and their sequence complementarity with the supernumerary chromosomes observed in Prochilodus lineatus (Valenciennes, 1836) and Prochilodus argenteus Agassiz, 1829 was investigated. The hybridization patterns obtained with chromosome painting using the micro B probe of P. costatus and the satDNA SATH1 mapping made it possible to assume homology of sequences between the B chromosomes of these congeneric species. Our results suggest that the origin of B chromosomes in the genus Prochilodus is a phylogenetically old event. PMID:28919971

  13. Comparative cytogenetics of two endangered leuciscine fish, Squalius aradensis and S. torgalensis (Teleostei, Cyprinidae), from the Iberian Peninsula

    PubMed Central

    Nabais, Catarina; Rampin, Massimiliano; Collares-Pereira, Maria João

    2013-01-01

    Abstract In this study, the description of the karyotypes of the endangered chubs Squalius aradensis (Coelho, Bogutskaya, Rodrigues and Collares-Pereira, 1998) and Squalius torgalensis (Coelho, Bogutskaya, Rodrigues and Collares-Pereira, 1998) is presented by means of conventional (Giemsa-staining, Chromomycin A3 (CMA3)-fluorescence, Silver-impregnation (Ag-NORs)) and molecular (fluorescence in situ hybridization (FISH) with 18S rDNA probe) protocols. These endemic sister-species have an allopatric but adjacent distribution in the most southwestern part of the Iberian Peninsula. Diploid chromosome number was invariably 2n = 50 and karyotypes of both species were grossly similar, composed of metacentric and submetacentric elements with a reduced number of acrocentric pairs. Sequential staining using FISH with an 18S rDNA probe, CMA3 and Ag-NORs treatments revealed consistent positive signals located at the end of the short arms of a submetacentric chromosome pair, likely homologous in both species. While providing useful cytogenetic comparative data against other members of the genus Squalius Bonaparte, 1837, the work aimed to draw attention towards the conservation of two narrow-range and highly confined fish species. PMID:24260688

  14. A preliminary assessment of genetic divergence and distribution of Malagasy cave fish in the genus Typhleotris (Teleostei: Milyeringidae).

    PubMed

    Vences, Miguel; Rasoloariniaina, Jean R; Riemann, Jana C

    2018-02-08

    The genus Typhleotris contains three poorly known blind fish species, inhabiting aquifers in the limestone plateau of south-western Madagascar. Until recently these species were known from only few localities, and their pattern of genetic differentiation remains poorly studied. In this study we analyse 122 Typhleotris tissue samples collected from 12 localities, spanning the entire known range of the genus, and use DNA sequences to assign these samples to the three species known. The phylogeny based on the mitochondrial marker cox1 revealed three main clades corresponding to the three species: Typhleotris madagascariensis, T. mararybe and T. pauliani, differing by uncorrected pairwise sequence divergences of 6.3-9.8%. The distribution ranges of the three species overlapped widely: T. mararybe was collected only in a southern group of localities, T. madagascariensis was found in both the southern and the central group of localities, and T. pauliani occurred from the northernmost site to the southern group of localities; yet the three species did not share haplotypes in two nuclear genes, except for three individuals that we hypothesize are hybrids of T. pauliani with T. madagascariensis and T. mararybe. This pattern of concordant mitochondrial and nuclear divergence despite sympatry strongly supports the status of all three taxa as separate species. Phylogeographic structure was obvious in T. madagascariensis, with two separate shallow mitochondrial clades occupying (1) the central vs. (2) the southern group of populations, and in T. pauliani, with separate mitochondrial clades for (1) the northern vs. (2) the central/southern populations. The widespread occurrence of these three cave fish species suggests that the aquifers in south-western Madagascar have at least in the past allowed episodic dispersal and gene flow of subterraneous organisms, whereas the phylogeographic pattern of T. madagascariensis and T. pauliani provides evidence for isolation and loss of connectivity in the more recent past.

  15. Maternal-embryonic metabolic and antioxidant response of Chapalichthys pardalis (Teleostei: Goodeidae) induced by exposure to 3,4-dichloroaniline.

    PubMed

    Carbajal-Hernández, Ana Laura; Valerio-García, Roberto Carlos; Martínez-Ruíz, Erika Berenice; Jarquín-Díaz, Víctor Hugo; Martínez-Jerónimo, Fernando

    2017-07-01

    Chapalichthys pardalis is a viviparous fish, microendemic to the Tocumbo Region in the state of Michoacán, Mexico. Despite the peculiar type of reproduction of goodeid fish and their mother-embryo interaction, the effects on embryos induced by maternal exposure to aquatic xenobiotics are still unknown. The objective of the present work was to determine the maternal-embryonic metabolic and antioxidant response of C. pardalis exposed to 3,4-dichloroaniline (3,4-DCA), a compound considered highly noxious to the environment because of its high toxicity and persistence, which has been used as reference toxicant in toxicological bioassays. We determined the median lethal concentration (LC 50 , 96 h) and then exposed pregnant females to 3.3, 2.5, and 0.5 mg L -1 of 3,4-DCA (equivalent to LC 1 , LC 0.01 , and LC 50/10 , respectively) during 21 days. We assessed the activity of antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), macromolecules content (proteins, lipids, carbohydrates), glucose, and lactate concentration, as well as the oxidative damage, by measuring thiobarbituric acid reactive substances, and protein oxidation. To interpret results, we used the integrated biomarker response (IBRv2). The average LC 50 was of 5.18 mg L -1 (4.8-5.5 mg L -1 ; p = 0.05). All females exposed to concentrations of 3.3 and 2.5 mg L -1 lost 100% of the embryos during the bioassay, whereas those exposed to 0.5 mg L -1 showed alterations in the antioxidant activity and oxidative damage, being the embryos and the maternal liver the most affected, with IBRv2 values of 10.09 and 9.21, respectively. Damage to macromolecules was greater in embryos and the maternal liver, with IBRv2 of 16.14 and 8.40, respectively. We conclude that exposure to xenobiotics, like 3,4-DCA, in species with a marked maternal-embryonic interaction represents a potential risk for the development and survival of the descendants, thereby, potentially affecting the future of the population.

  16. Systematics of the grey mullets (Teleostei: Mugiliformes: Mugilidae): molecular phylogenetic evidence challenges two centuries of morphology-based taxonomy.

    PubMed

    Durand, J-D; Shen, K-N; Chen, W-J; Jamandre, B W; Blel, H; Diop, K; Nirchio, M; Garcia de León, F J; Whitfield, A K; Chang, C-W; Borsa, P

    2012-07-01

    The family Mugilidae comprises mainly coastal marine species that are widely distributed in all tropical, subtropical and temperate seas. Mugilid species are generally considered to be ecologically important and they are a major food resource for human populations in certain parts of the world. The taxonomy and systematics of the Mugilidae are still much debated and based primarily on morphological characters. In this study, we provide the first comprehensive molecular systematic account of the Mugilidae using phylogenetic analyses of nucleotide sequence variation at three mitochondrial loci (16S rRNA, cytochrome oxidase I, and cytochrome b) for 257 individuals from 55 currently recognized species. The study covers all 20 mugilid genera currently recognized as being valid. The family comprises seven major lineages that radiated early on from the ancestor to all current forms. All genera that were represented by two species or more, except Cestraeus, turned out to be paraphyletic or polyphyletic. Thus, the present phylogenetic results generally disagree with the current taxonomy at the genus level and imply that the anatomical characters used for the systematics of the Mugilidae may be poorly informative phylogenetically. The present results should provide a sound basis for a taxonomic revision of the mugilid genera. A proportion of the species with large distribution ranges (including Moolgarda seheli, Mugil cephalus and M. curema) appear to consist of cryptic species, thus warranting further taxonomic and genetic work at the infra-generic level. Copyright © 2012 Elsevier Inc. All rights reserved.

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

    PubMed Central

    2011-01-01

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

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

    PubMed

    Nakatani, Masanori; Miya, Masaki; Mabuchi, Kohji; Saitoh, Kenji; Nishida, Mutsumi

    2011-06-22

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

  19. Cardiorespiratory responses of the facultative air-breathing fish jeju, Hoplerythrinus unitaeniatus (Teleostei, Erythrinidae), exposed to graded ambient hypoxia.

    PubMed

    Oliveira, R D; Lopes, J M; Sanches, J R; Kalinin, A L; Glass, M L; Rantin, F T

    2004-12-01

    The jeju, Hoplerythrinus unitaeniatus, is equipped with a modified part of the swim bladder that allows aerial respiration. On this background, we have evaluated its respiratory and cardiovascular responses to aquatic hypoxia. Its aquatic O2 uptake (V(O2)) was maintained constant down to a critical P(O2) (P(cO2)) of 40 mm Hg, below which V(O2) declined linearly with further reductions of P(iO2). Just below P(cO2), the ventilatory tidal volume (V(T)) increased significantly along with gill ventilation (V(G)), while respiratory frequency changed little. Consequently, water convection requirement (V(G)/V(O2)) increased steeply. The same threshold applied to cardiovascular responses that included reflex bradycardia and elevated arterial blood pressure (P(a)). Aerial respiration was initiated at water P(O2) of 44 mm Hg and breathing episodes and time at the surface increased linearly with more severe hypoxia. At the lowest water P(O2) (20 mm Hg), the time spent at the surface accounted for 50% of total time. This response has a character of a temporary emergency behavior that may allow the animal to escape hypoxia.

  20. A new species of the genus Capoeta Valenciennes, 1842 from the Caspian Sea basin in Iran (Teleostei, Cyprinidae)

    PubMed Central

    Jouladeh-Roudbar, Arash; Eagderi, Soheil; Ghanavi, Hamid Reza; Doadrio, Ignacio

    2017-01-01

    Abstract A new species of algae-scraping cyprinid of the genus Capoeta Valenciennes, 1842 is described from the Kheyroud River, located in the southern part of the Caspian Sea basin in Iran. The species differs from other members of this genus by a combination of the following characters: one pair of barbels; predorsal length equal to postdorsal length; maxillary barbel slightly smaller than eye’s horizontal diameter and reach to posterior margin of orbit; intranasal length slightly shorter than snout length; lateral line with 46–54 scales; 7–9 scales between dorsal-fin origin and lateral line, and 6–7 scales between anal-fin origin and lateral line. PMID:28769726

  1. 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

  2. Phylogenetic patterns in populations of Chilean species of the genus Orestias (Teleostei: Cyprinodontidae): results of mitochondrial DNA analysis.

    PubMed

    Lüssen, Arne; Falk, Thomas M; Villwock, Wolfgang

    2003-10-01

    Patterns of molecular genetic differentiation among taxa of the "agassii species complex" (Parenti, 1984) were analysed based on partial mtDNA control region sequences. Special attention has been paid to Chilean populations of Orestias agassii and species from isolated lakes of northern Chile, e.g., O. agassii, Orestias chungarensis, Orestias parinacotensis, Orestias laucaensis, and Orestias ascotanensis. Orestias tschudii, Orestias luteus, and Orestias ispi were analysed comparatively. Our findings support the utility of mtDNA control region sequences for phylogenetic studies within the "agassii species complex" and confirmed the monophyly of this particular lineage, excluding O. luteus. However, the monophyly of further morphologically defined lineages within the "agassii complex" appears doubtful. No support was found for the utility of these data sets for inferring phylogenetic relationships between more distantly related taxa originating from Lake Titicaca.

  3. Eoalosa janvieri gen. et sp. nov., a new clupeid fish (Teleostei, Clupeiformes) from the Eocene of Monte Bolca, Italy.

    PubMed

    Marramà, Giuseppe; Carnevale, Giorgio

    2018-01-01

    Fishes of the family Clupeidae are extremely abundant in the Eocene fossiliferous limestone of Monte Bolca representing the most common group from this celebrated locality. A new clupeid from the Pesciara site, Eoalosa janvieri gen. et sp. nov., is described. The new taxon exhibits a unique combination of characters supporting its recognition as a new genus and species of clupeid fish that is tentatively placed in the subfamily Alosinae. The description of this new taxon improves our knowledge of the diversity of clupeoid fishes in the Eocene of Monte Bolca.

  4. 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

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

    Treesearch

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

    2013-01-01

    There is growing interest in broad-scale biodiversity assessments that can serve as benchmarks for identifying ecological change. Genetic tools have been used for such assessments for decades, but spatial sampling considerations have largely been ignored. Here, we demonstrate how intensive sampling efforts across a large geographical scale can influence identification...

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

    PubMed Central

    Altner, Melanie; Reichenbacher, Bettina

    2015-01-01

    The extant Cyprinodontiformes (killifishes) with their two suborders Cyprinodontoidei and Aplocheiloidei represent a diverse and well-studied group of fishes. However, their fossil record is comparatively sparse and has so far yielded members of the Cyprinodontoidei only. Here we report on cyprinodontiform fossils from the upper Miocene Lukeino Formation in the Tugen Hills of the Central Rift Valley of Kenya, which represent the first fossil record of an aplocheiloid killifish. A total of 169 specimens - mostly extraordinarily well preserved - and a sample of ten extant cyprinodontiform species were studied on the basis of morphometrics, meristics and osteology. A phylogenetic analysis using PAUP was also conducted for the fossils. Both the osteological data and the phylogenetic analysis provide strong evidence for the assignment of the fossils to the Aplocheiloidei, and justify the definition of the new family †Kenyaichthyidae, the new genus †Kenyaichthys and the new species †K. kipkechi sp. nov. The phylogenetic analysis unexpectedly places †Kenyaichthys gen. nov. in a sister relationship to the Rivulidae (a purely Neotropical group), a probable explanation might be lack of available synapomorphies for the Rivulidae, Nothobranchiidae and Aplocheilidae. The specimens of †K. kipkechi sp. nov. show several polymorphic characters and large overlap in meristic traits, which justifies their interpretation as a species flock in statu nascendi. Patterns of variation in neural and haemal spine dimensions in the caudal vertebrae of †Kenyaichthys gen. nov. and the extant species studied indicate that some previously suggested synapomorphies of the Cyprinodontoidei and Aplocheiloidei need to be revised. PMID:25923654

  7. A new mesophotic goby, Palatogobius incendius (Teleostei: Gobiidae), and the first record of invasive lionfish preying on undescribed biodiversity

    PubMed Central

    Baldwin, Carole C.

    2017-01-01

    A new species of deep-reef fish in the goby genus Palatogobius is described from recent submersible collections off Curaçao and Dominica. Video footage of schools of this species reveal predation by the invasive Indo-Pacific lionfish (Pterois spp.), the first record of undescribed fauna potentially being eaten by lionfish outside of its native range. We present molecular phylogenetic data for all valid species of Palatogobius and related genera, as well as a taxonomic key to the species of Palatogobius and a generic key to Palatogobius and related genera in the western Atlantic. Lastly, we discuss ecological and behavioral aspects of some deep-reef fishes in light of potential threats from invasive lionfish. PMID:28542432

  8. A new mesophotic goby, Palatogobius incendius (Teleostei: Gobiidae), and the first record of invasive lionfish preying on undescribed biodiversity.

    PubMed

    Tornabene, Luke; Baldwin, Carole C

    2017-01-01

    A new species of deep-reef fish in the goby genus Palatogobius is described from recent submersible collections off Curaçao and Dominica. Video footage of schools of this species reveal predation by the invasive Indo-Pacific lionfish (Pterois spp.), the first record of undescribed fauna potentially being eaten by lionfish outside of its native range. We present molecular phylogenetic data for all valid species of Palatogobius and related genera, as well as a taxonomic key to the species of Palatogobius and a generic key to Palatogobius and related genera in the western Atlantic. Lastly, we discuss ecological and behavioral aspects of some deep-reef fishes in light of potential threats from invasive lionfish.

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

    PubMed Central

    2017-01-01

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

  10. Genetic divergence and phylogenetic relationships in grey mullets (Teleostei: Mugilidae) based on PCR-RFLP analysis of mtDNA segments.

    PubMed

    Papasotiropoulos, V; Klossa-Kilia, E; Kilias, G; Alahiotis, S

    2002-04-01

    The genetic differentiation and phylogenetic relationships among five species of the Mugilidae family (Mugil cephalus, Chelon labrosus, Liza aurata, Liza ramada, and Liza saliens) were investigated at the mtDNA level, on samples taken from Messolongi lagoon-Greece. RFLP analysis of three PCR-amplified mtDNA gene segments (12s rRNA, 16s rRNA, and CO I) was used. Ten, eight, and nine restriction enzymes were found to have at least one recognition site at 12s rRNA, 16s rRNA, and CO I genes, respectively. Several fragment patterns were revealed to be species-specific, and thus they could be useful in species taxonomy as diagnostic markers, as well as for further evolutionary studies. Seven different haplotypes were detected. The greatest amount of genetic differentiation was observed at the interspecific level, while little variation was revealed at the intraspecific level. The highest values of nucleotide sequence divergence were observed between M. cephalus and all the other species, while the lowest was found between C. labrosus and L. saliens. Dendrograms obtained by the three different methods (UPGMA, Neighbor-Joining, and Dollo parsimony), were found to exhibit in all cases the same topology. According to this, the most distinct species is M. cephalus, while the other species are clustered in two separate groups, thefirst one containing L. aurata and L. ramada, the other L. saliens and C. labrosus. This last clustering makes the monophyletic origin of the genus Liza questionable.

  11. A comparative study of Ligophorus uruguayense and L. saladensis (Monogenea: Ancyrocephalidae) from Mugil liza (Teleostei: Mugilidae) in southern Brazil.

    PubMed

    Marchiori, Natalia C; Pariselle, Antoine; Pereira, Joaber; Agnese, Jean-Francois; Durand, Jean-Dominique; Vanhove, Maarten P M

    2015-01-01

    Representatives of Ligophorus Euzet et Suriano, 1977 were found on the gills of Mugil liza Valenciennes caught in southern Brazil. They were identified as Ligophorus uruguayense Failla Siquier et Ostrowski de Núñez, 2009 and Ligophorus saladensis Marcotegui et Martorelli, 2009, even though specific identification proved to be difficult due to inconsistencies in some diagnostic features reported for these two species. Therefore, a combined morphological and molecular approach was used to critically review the validity of these species, by means of phase contrast and confocal fluorescence microscopical examination of sclerotised hard parts, and assessing the genetic divergence between L. saladensis, L. uruguayense and their congeners using rDNA sequences. The main morphological differences between the two species relate to the shape of the accessory piece of the penis and the median process of the ventral bar. The accessory piece in L. uruguayense is shorter than in L. saladensis, has a cylindrical, convex upper lobe and straight lower lobe (vs with the distal tip of the lower lobe turning away from the upper lobe in the latter species). The ventral bar has a V-shaped anterior median part in L. uruguayense (vs U-shaped in L. saladensis). The two species are suggested to be part of a species complex together with L. mediterraneus Sarabeev, Balbuena et Euzet, 2005. We recommend to generalise such comparative assessment of species of Ligophorus for a reliable picture of the diversity and diversification mechanisms within the genus, and to make full use of its potential as an additional marker for mullet taxonomy and systematics.

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

    PubMed

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

    2007-11-01

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

  13. Three new species of Ligophorus (Monogenea: Dactylogyridae) on the gills of Mugil cephalus (Teleostei: Mugilidae) from the Japan Sea.

    PubMed

    Rubtsova, Nataliya Y; Balbuena, Juan A; Sarabeev, Volodimir L

    2007-08-01

    Comparative morphology and multivariate morphometric analysis of monogeneans collected on flathead mullets Mugil cephalus from 2 Russian localities of the Japan Sea revealed the presence of 3 new species of Ligophorus, namely, L. domnichi n. sp., L. pacificus n. sp., and L. cheleus n. sp., which are described herein. So far, only 1 species of dactylogyrid monogenean identified as Ligophorus chabaudi was known on flathead mullets in this sea, but after comparison with the present material, we propose that this form actually represents L. domnichi n. sp. Results support previous zoogeographical evidence, suggesting that flathead mullets from different seas harbor different species complexes of Ligophorus. One interesting finding is that the 3 new species have a U-shaped ovary, whereas ovate ovaries have been reported in previous descriptions of species of the genus, e.g., L. vanbenedenii, L. parvicirrus, L. imitans, and L. chongmingensis. The U-shaped ovary was revealed only when the worms were observed in lateral view. The additional examination of L. vanbenedenii, L. parvicirrus, L. imitans, and L. pilengas specimens from our collections also revealed a U-shaped ovary in these forms as well. Further studies should establish whether or not this character is shared by all members of the genus.

  14. Onychostoma brevibarba, a new cyprinine fish (Pisces: Teleostei) from the middle Chang Jiang basin in Hunan Province, South China.

    PubMed

    Song, Xue-Ling; Cao, Liang; Zhang, E

    2018-04-16

    Onychostoma brevibarba, a new cyprinid species, is described from two tributaries flowing into the Xiang Jiang (= River) of the middle Chang Jiang basin in Hunan Province, South China. The new species is morphologically similar to two Chinese congeners, O. minnanense and O. barbatulum, but differs from them in the anteromedian extension of the postlabial groove. It further differs from O. minnanense in the maxillary-barbel length, shape and body coloration, and from O. barbatulum in the number of lateral-line perforated scales and the width of the mouth opening. The validity of the new species and its close relationship with these two species were affirmed by a molecular phylogenetic analysis based on the mitochondrial cyt b and CO1 genes.

  15. Pseudotrichonotus belos new species, first record of the fish family Pseudotrichonotidae from Australia (Teleostei: Aulopiformes).

    PubMed

    Gill, Anthony C; Pogonoski, John J

    2016-12-05

    Pseudotrichonotus belos new species, described from three specimens trawled in 100-120 m offshore between Exmouth Gulf and Shark Bay, Western Australia, represents the first record of the sand-diving fish family Pseudotrichonotidae from Australian waters. It differs from its two congeners in having a more posteriorly positioned dorsal fin (predorsal length 39.6-41.2 % SL) and fewer dorsal- and anal-fin rays (31-33 and 12, respectively).

  16. Pseudempleurosoma haywardi sp. nov. (Monogenea: Ancyrocephalidae (sensu lato) Bychowsky & Nagibina, 1968): An endoparasite of croakers (Teleostei: Sciaenidae) from Indonesia

    PubMed Central

    Palm, Harry W.; Al-Jufaili, Sarah H.; Kleinertz, Sonja

    2017-01-01

    An endoparasitic monogenean was identified for the first time from Indonesia. The oesophagus and anterior stomach of the croakers Nibea soldado (Lacépède) and Otolithes ruber (Bloch & Schneider) (n = 35 each) sampled from the South Java coast in May 2011 and Johnius amblycephalus (Bleeker) (n = 2) (all Sciaenidae) from Kedonganan fish market, South Bali coast, in November 2016, were infected with Pseudempleurosoma haywardi sp. nov. Prevalences in the first two croakers were 63% and 46%, respectively, and the two J. amblycephalus harboured three and five individuals. All three croakers represent new hosts for this monogenean genus. We provide infection rates, light microscopical observations, 3D confocal microscopical illustrations, and a morphometric comparison with all congeners. The new species differs in body size, the position and shape of the ovary and testes, and especially in the composition of the dorsal anchor complex, with the dorsal bar being anteriorly concave rather than planar or convex as in its congeners. The dorsal and ventral anchors of this new species are the longest in the genus, whereas the male copulatory organ is the smallest. The first DNA sequences for a member of this genus demonstrate the greatest similarity with endoparasitic freshwater monogeneans from African cichlid fishes. This suggests a freshwater origin for these marine endoparasitic monogeneans. PMID:28880928

  17. Mitochondrial phylogeny of Chinese barred species of the cyprinid genus Acrossocheilus Oshima, 1919 (Teleostei: Cypriniformes) and its taxonomic implications.

    PubMed

    Yuan, Le-Yang; Liu, Xiao-Xiang; Zhang, E

    2015-12-21

    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).

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

    PubMed

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

    2007-04-01

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

  19. Not a simple case - A first comprehensive phylogenetic hypothesis for the Midas cichlid complex in Nicaragua (Teleostei: Cichlidae: Amphilophus).

    PubMed

    Geiger, Matthias F; McCrary, Jeffrey K; Schliewen, Ulrich K

    2010-09-01

    Nicaraguan Midas cichlids from crater lakes have recently attracted attention as potential model systems for speciation research, but no attempt has been made to comprehensively reconstruct phylogenetic relationships of this highly diverse and recently evolved species complex. We present a first AFLP (2793 loci) and mtDNA based phylogenetic hypothesis including all described and several undescribed species from six crater lakes (Apoyeque, Apoyo, Asososca Leon, Masaya, Tiscapa and Xiloá), the two great Lakes Managua and Nicaragua and the San Juan River. Our analyses demonstrate that the relationships between the Midas cichlid members are complex, and that phylogenetic information from different markers and methods do not always yield congruent results. Nevertheless, monophyly support for crater lake assemblages from Lakes Apoyeque, Apoyo, A. Leon is high as compared to those from L. Xiloá indicating occurrence of sympatric speciation. Further, we demonstrate that a 'three species' concept for the Midas cichlid complex is inapplicable and consequently that an individualized and voucher based approach in speciation research of the Midas cichlid complex is necessary at least as long as there is no comprehensive revision of the species complex available. Copyright 2010 Elsevier Inc. All rights reserved.

  20. Composition and structure of the parasite faunas of cod, Gadus morhua L. (Teleostei: Gadidae), in the North East Atlantic.

    PubMed

    Perdiguero-Alonso, Diana; Montero, Francisco E; Raga, Juan Antonio; Kostadinova, Aneta

    2008-07-18

    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. 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. 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. 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.

  1. A “Rosetta Stone” for metazoan zooplankton: DNA barcode analysis of species diversity of the Sargasso Sea (Northwest Atlantic Ocean)

    NASA Astrophysics Data System (ADS)

    Bucklin, Ann; Ortman, Brian D.; Jennings, Robert M.; Nigro, Lisa M.; Sweetman, Christopher J.; Copley, Nancy J.; Sutton, Tracey; Wiebe, Peter H.

    2010-12-01

    Species diversity of the metazoan holozooplankton assemblage of the Sargasso Sea, Northwest Atlantic Ocean, was examined through coordinated morphological taxonomic identification of species and DNA sequencing of a ˜650 base-pair region of mitochondrial cytochrome oxidase I (mtCOI) as a DNA barcode (i.e., short sequence for species recognition and discrimination). Zooplankton collections were made from the surface to 5,000 meters during April, 2006 on the R/V R.H. Brown. Samples were examined by a ship-board team of morphological taxonomists; DNA barcoding was carried out in both ship-board and land-based DNA sequencing laboratories. DNA barcodes were determined for a total of 297 individuals of 175 holozooplankton species in four phyla, including: Cnidaria (Hydromedusae, 4 species; Siphonophora, 47); Arthropoda (Amphipoda, 10; Copepoda, 34; Decapoda, 9; Euphausiacea, 10; Mysidacea, 1; Ostracoda, 27); and Mollusca (Cephalopoda, 8; Heteropoda, 6; Pteropoda, 15); and Chaetognatha (4). Thirty species of fish (Teleostei) were also barcoded. For all seven zooplankton groups for which sufficient data were available, Kimura-2-Parameter genetic distances were significantly lower between individuals of the same species (mean=0.0114; S.D. 0.0117) than between individuals of different species within the same group (mean=0.3166; S.D. 0.0378). This difference, known as the barcode gap, ensures that mtCOI sequences are reliable characters for species identification for the oceanic holozooplankton assemblage. In addition, DNA barcodes allow recognition of new or undescribed species, reveal cryptic species within known taxa, and inform phylogeographic and population genetic studies of geographic variation. The growing database of "gold standard" DNA barcodes serves as a Rosetta Stone for marine zooplankton, providing the key for decoding species diversity by linking species names, morphology, and DNA sequence variation. In light of the pivotal position of zooplankton in ocean

  2. Body-induced vortical flows: a common mechanism for self-corrective trimming control in boxfishes.

    PubMed

    Bartol, Ian K; Gharib, Morteza; Webb, Paul W; Weihs, Daniel; Gordon, Malcolm S

    2005-01-01

    Boxfishes (Teleostei: Ostraciidae) are marine fishes having rigid carapaces that vary significantly among taxa in their shapes and structural ornamentation. We showed previously that the keels of the carapace of one species of tropical boxfish, the smooth trunkfish, produce leading edge vortices (LEVs) capable of generating self-correcting trimming forces during swimming. In this paper we show that other tropical boxfishes with different carapace shapes have similar capabilities. We conducted a quantitative study of flows around the carapaces of three morphologically distinct boxfishes (spotted boxfish, scrawled cowfish and buffalo trunkfish) using stereolithographic models and three separate but interrelated analytical approaches: digital particle image velocimetry (DPIV), pressure distribution measurements, and force balance measurements. The ventral keels of all three forms produced LEVs that grew in circulation along the bodies, resembling the LEVs produced around delta-winged aircraft. These spiral vortices formed above the keels and increased in circulation as pitch angle became more positive, and formed below the keels and increased in circulation as pitch angle became more negative. Vortices also formed along the eye ridges of all boxfishes. In the spotted boxfish, which is largely trapezoidal in cross section, consistent dorsal vortex growth posterior to the eye ridge was also present. When all three boxfishes were positioned at various yaw angles, regions of strongest concentrated vorticity formed in far-field locations of the carapace compared with near-field areas, and vortex circulation was greatest posterior to the center of mass. In general, regions of localized low pressure correlated well with regions of attached, concentrated vorticity, especially around the ventral keels. Although other features of the carapace also affect flow patterns and pressure distributions in different ways, the integrated effects of the flows were consistent for all forms

  3. Lineage-specific evolution of the vertebrate Otopetrin gene family revealed by comparative genomic analyses

    PubMed Central

    2011-01-01

    Background Mutations in the Otopetrin 1 gene (Otop1) in mice and fish produce an unusual bilateral vestibular pathology that involves the absence of otoconia without hearing impairment. The encoded protein, Otop1, is the only functionally characterized member of the Otopetrin Domain Protein (ODP) family; the extended sequence and structural preservation of ODP proteins in metazoans suggest a conserved functional role. Here, we use the tools of sequence- and cytogenetic-based comparative genomics to study the Otop1 and the Otop2-Otop3 genes and to establish their genomic context in 25 vertebrates. We extend our evolutionary study to include the gene mutated in Usher syndrome (USH) subtype 1G (Ush1g), both because of the head-to-tail clustering of Ush1g with Otop2 and because Otop1 and Ush1g mutations result in inner ear phenotypes. Results We established that OTOP1 is the boundary gene of an inversion polymorphism on human chromosome 4p16 that originated in the common human-chimpanzee lineage more than 6 million years ago. Other lineage-specific evolutionary events included a three-fold expansion of the Otop genes in Xenopus tropicalis and of Ush1g in teleostei fish. The tight physical linkage between Otop2 and Ush1g is conserved in all vertebrates. To further understand the functional organization of the Ushg1-Otop2 locus, we deduced a putative map of binding sites for CCCTC-binding factor (CTCF), a mammalian insulator transcription factor, from genome-wide chromatin immunoprecipitation-sequencing (ChIP-seq) data in mouse and human embryonic stem (ES) cells combined with detection of CTCF-binding motifs. Conclusions The results presented here clarify the evolutionary history of the vertebrate Otop and Ush1g families, and establish a framework for studying the possible interaction(s) of Ush1g and Otop in developmental pathways. PMID:21261979

  4. Metazoan fish parasites of Macrourus berglax Lacepède, 1801 and other macrourids of the North Atlantic: Invasion of the deep sea from the continental shelf

    NASA Astrophysics Data System (ADS)

    Palm, H. W.; Klimpel, S.

    2008-01-01

    Between 2001 and 2003, a total of 105 Macrourus berglax Lacepède, 1801 were collected from Irminger Sea, at depths between 250 and 450 m, and were studied for parasites. Twenty-four different parasite species were identified. Nematodes (eight spp.) and digeneans (six spp.) were the most species rich, followed by crustaceans (four spp.), cestodes (three spp.), acanthocephalans (two spp.) and monogeneans (one sp.). Core species included the digenean Gonocerca phycidis (maximum 62.9% prevalence), the nematodes Anisakis sp. (62.9%), Capillaria gracilis (65.8%), Hysterothylacium aduncum (60.0%), Neoascarophis macrouri (88.6%), Spinitectus oviflagellis (82.9%), and the acanthocephalan Echinorhynchus gadi (97.1%). M. berglax was the final host for most of the parasites, and was infested with only a few larval forms. The species composition, diversity as well as the prevalence and intensity of infestation for most parasite species collected, were similar in the different years, indicating no distinct interannual variation at this deep-sea locality. Comparisons of the parasite fauna of M. berglax with macrourids belonging to the genera Macrourus, Coryphaenoides, Coelorhynchus and Nezumia revealed a similar infestation pattern amongst these deep-sea fish, consisting of the same or closely related species. This observation suggests that the parasite life-cycles in these benthopelagic deep-sea fishes follow similar pathways independent of geographical location. A similar habitat and food preference of macrourids results in a similar parasite fauna. The host specificity of some of the parasites is low, with most species (nine) infesting Teleostei, Gadiformes (six), Macrouridae (two), Macrourus spp. (one) and specifically M. berglax (five). Overlapping infestation patterns of M. berglax parasites with phylogenetically related gadiform fish from the continental shelf region suggest that the deep-sea parasite fauna in macrourids has evolved along with their hosts from parasite

  5. Life history and initial assessment of fishing impacts on the by-catch species Dules auriga (Teleostei: Serranidae) in southern Brazil.

    PubMed

    Rovani, A T; Cardoso, L G

    2017-09-01

    The life history of Dules auriga, a small hermaphrodite serranid species inhabiting deep waters and a frequent component of the discarded catch of bottom trawling in southern Brazil, was studied to assess the fishery effects on the stock through the estimation of the remaining spawning-potential ratio. Sampling was conducted throughout a year and included specimens to determine sex, maturity and age. Age was validated by the edge type and marginal-increment analysis. The oldest and the largest individuals were 9 years and 195 mm total length. Growth parameters fitted to the von Bertalanffy equation were L ∞ = 178·34 mm, k = 0·641 year -1 and t 0 = -0·341 years. Length and age at first maturity were 140·72 mm and 2 years, respectively. The reproductive season was throughout the austral spring and summer. The assessment of the effects of fishing showed that it may have resulted in a loss of 50% of the spawning potential. This loss may be higher when taking into account the uncertainty in the life-history parameters and could be considered of concern for the population. Fast growth, moderate longevity, long spawning season, small size and age at maturity make D. auriga relatively resilient to the removal of biomass by fishing. When considering the uncertainty, however, the losses of the spawning potential have been severely reducing the population resilience in the face of ecosystem changes. © 2017 The Fisheries Society of the British Isles.

  6. 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.

  7. Schistura megalodon species nova, a new river loach from the Irra-waddy basin in Dehong, Yunnan, China (Teleostei: Cypriniformes: Nemacheilidae)

    PubMed Central

    Endruweit, Marco

    2014-01-01

    A new species of river loach, Schistura megalodon sp. nov., is described from the Irrawaddy basin in Yingjiang County, Dehong Autonomous Prefecture, Yunnan Province, China. The following combination of diagnostic characters serve to distinguish it from all other congeners in the given zoogeographical region: a large processus dentiformes in the upper jaw, a short pre-anus length of 65.4%-66.3% of SL, long paired fins (pectoral: 20.8%-24.2% of SL; pelvic: 17.9%-20.6% of SL), a wide body of 9.7%-11.3% of SL at anal fin origin, an incomplete lateral line, the absence of an orbital lobe, and a broad and distinct basicaudal bar with forward extensions. PMID:25297074

  8. Schistura megalodon species nova, a new river loach from the Irra-waddy basin in Dehong, Yunnan, China (Teleostei: Cypriniformes: Nemacheilidae).

    PubMed

    Endruweit, Marco

    2014-09-01

    A new species of river loach, Schistura megalodon sp. nov., is described from the Irrawaddy basin in Yingjiang County, Dehong Autonomous Prefecture, Yunnan Province, China. The following combination of diagnostic characters serve to distinguish it from all other congeners in the given zoogeographical region: a large processus dentiformes in the upper jaw, a short pre-anus length of 65.4%-66.3% of SL, long paired fins (pectoral: 20.8%-24.2% of SL; pelvic: 17.9%-20.6% of SL), a wide body of 9.7%-11.3% of SL at anal fin origin, an incomplete lateral line, the absence of an orbital lobe, and a oad and distinct basicaudal bar with forward extensions.

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

    USGS Publications Warehouse

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

    2012-01-01

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

  10. Comparative proteome and peptidome analysis of the cephalic fluid secreted by Arapaima gigas (Teleostei: Osteoglossidae) during and outside parental care

    PubMed Central

    Migaud, Hervé; Doherty, Mary K.; Siwy, Justyna; Mullen, Willian; Mesquita, Pedro E. C.; Albalat, Amaya

    2017-01-01

    Parental investment in Arapaima gigas includes nest building and guarding, followed by a care provision when a cephalic fluid is released from the parents’ head to the offspring. This fluid has presumably important functions for the offspring but so far its composition has not been characterised. In this study the proteome and peptidome of the cephalic secretion was studied in parental and non-parental fish using capillary electrophoresis coupled to mass spectrometry (CE-MS) and GeLC-MS/MS analyses. Multiple comparisons revealed 28 peptides were significantly different between males and parental males (PC-males), 126 between females and parental females (PC-females), 51 between males and females and 9 between PC-males and PC-females. Identification revealed peptides were produced in the inner ear (pcdh15b), eyes (tetraspanin and ppp2r3a), central nervous system (otud4, ribeye a, tjp1b and syn1) among others. A total of 422 proteins were also identified and gene ontology analysis revealed 28 secreted extracellular proteins. From these, 2 hormones (prolactin and stanniocalcin) and 12 proteins associated to immunological processes (serotransferrin, α-1-antitrypsin homolog, apolipoprotein A-I, and others) were identified. This study provides novel biochemical data on the lateral line fluid which will enable future hypotheses-driven experiments to better understand the physiological roles of the lateral line in chemical communication. PMID:29065179

  11. Oxynoemacheilus zarzianus, a new loach from the Lesser Zab River drainage in Iraqi Kurdistan (Teleostei: Nemacheilidae).

    PubMed

    Freyhof, Jörg; Geiger, Matthias

    2017-06-02

    Oxynoemacheilus zarzianus, new species, is described from the Lesser Zab River drainage, a tributary of the lower Tigris. It is distinguished from other Oxynoemacheilus species in the Tigris drainage by having a slightly emarginate caudal fin, no suborbital groove in males, a complete lateral line, the posterior process of the bony air-bladder capsule directed posteriorly, the flank and posterior part of back covered by scales, short barbels and a deep caudal peduncle. It is the fourth Oxynoemacheilus species known from the Lesser Zab drainage, where such loaches seem to be highly isolated in headwaters. Oxynoemacheilus species diversity in the Euphrates and Tigris drainage is exceptional high. Today 22 species are known from the entire Euphrates and Tigris drainage and 15 from the Tigris drainage alone.

  12. The Afro-Asian labeonine genus Garra Hamilton, 1822 (Teleostei, Cyprinidae) in the Pliocene of Central Armenia: Palaeoecological and palaeobiogeographical implications

    NASA Astrophysics Data System (ADS)

    Vasilyan, Davit; Carnevale, Giorgio

    2013-01-01

    Fossil skeletal remains of the Afro-Asian labeonine genus Garra are described on the basis of more than 300 specimens from the Pliocene diatomites of Jradzor, Central Armenia. Extant species of the genus Garra exhibit a wide distribution ranging from China, South Asia, and Borneo, through Middle East, the Arabian Peninsula, and Africa, where these fishes inhabit a variety of freshwater biotopes. The Pliocene fossils from the Jradzor site provide the first evidence of Garra in the fossil record. The inadequate preservation of the available material did not allow a detailed taxonomic attribution at the species level. Remains of Garra sp. were found associated to a moderately diverse assemblage, which includes also remains of additional freshwater fishes (Capoeta sp., Leuciscus cf. souffia, Leuciscus sp.), amphibians (Pelophylax cf. ridibundus), and large mammals (Rhinocerotidae indet.), as well as of monocotyledon plants. According to the diatom flora, the diatomites of Jradzor can be assigned to the Pliocene and were deposited in a freshwater lacustrine setting that was characterized by high productivity, eutrophic conditions, and standing macrophyte vegetation along the littoral zone. The presence of abundant resorptive pharyngeal teeth suggests that the Pliocene palaeolake of Jradzor was characterized by resident populations of Garra. Extant species of this genus are currently absent in the freshwaters of Armenia. The record of the genus Garra from Jradzor suggests that the Araks-Kura River drainage was connected, at least in part, with the Euphrates and Tigris River drainage during the Pliocene. The extinction of Garra (and other thermophilous taxa) from Araks and Kura River drainage was probably due to Plio-Pleistocene tectonic uplift of the Armenian Highland and consequent progressive climate cooling.

  13. Hidden diversity in deep-water bandfishes: review of Owstonia with descriptions of twenty-one new species (Teleostei: Cepolidae: Owstoniinae).

    PubMed

    Smith-Vaniz, William F; Johnson, G David

    2016-11-08

    The bandfish family Cepolidae, comprising the subfamilies Owstoniinae and Cepolinae, is characterized, and defining characters of the three groups are identified and discussed. Characters of larvae of both subfamilies are described and illustrated. Six nominal genera of owstoniines had been proposed by various authors, but we recognize only Owstonia Tanaka. Utility of selected identification characters of the genus are discussed. Differences in lateral-line patterns have been the primary character used by some recent authors for recognition of two owstoniine genera, with Sphenanthias Weber possessing the plesiomorphic lateral-line condition. Several other patterns also occur in these fishes bringing into question the phylogenetic significance of lateral line plasticity. Sexual dimorphism in pelvic fin lengths is also present in several species. Identification keys, descriptions, synonymies, distribution maps and photographs or illustrations are provided for all Owstonia species for which adults are available.        Although only 15 valid species were previously known, a remarkable hidden diversity of these fishes was discovered in major museum collections with the following 21 species here described as new: O. ainonaka (eastern Australia), O. contodon (Philippines), O. crassa (New Caledonia and Solomon Islands), O. dispar (Solomon Islands), O. elongata (New Caledonia and Vanuatu), O. fallax (eastern Australia and New Caledonia), O. geminata (Vanuatu and Philippines), O. hastata (eastern Australia), O. hawaiiensis (Hawaiian Islands); O. ignota (Mariana Islands), O. lepiota (Tanzania), O. melanoptera (Philippines), O. merensis (eastern Australia, Torres Strait), O. mundyi (Kiribati, Christmas Island), O. nalani (eastern Australia and New Caledonia), O. nudibucca (eastern Indian Ocean, Mentawai Islands and off Myanmar), O. psilos (Western Australia), O. raredonae (Mozambique), O. rhamma (Vanuatu), O. scottensis (Western Australia, Scott Reefs) and O. similis (Madagascar). Several specimens based on small juveniles, which we describe as Owstonia sp.,  appear to be additional new species but are not formally described as such.

  14. A New Species of Ligophorus (Monogenea: Dactylogyridae) from the gills of the Flathead Mullet Mugil cephalus (Teleostei: Mugilidae) from Mexico.

    PubMed

    Rodríguez-González, Abril; Míguez-Lozano, Raúl; Llopis-Belenguer, Cristina; Balbuena, Juan Antonio

    2015-12-01

    A new monogenean species, Ligophorus yucatanensis n. sp. from the gills of the flathead mullet Mugil cephalus from the Yucatan Peninsula, Mexico, is described. The new species can be differentiated from all other species of Ligophorus by the morphology of the accessory piece of the copulatory organ. Its main lobe is cylindrical, tunnelled expanded distally, slightly bowed with a characteristic membranous opening at level of medial bifurcation of the accessory piece, forming a thick-walled bulbshaped expansion that ends in a round labium. The secondary lobe is spatulate, straight, and shorter than the main lobe. In addition, the new species can be distinguished from other species by the morphology of the haptoral ventral bar, and the distal end of the vaginal duct. Furthermore the ventral anchors are shorter than those of all other species of Ligophorus reported in the Gulf of Mexico and Caribbean Sea. In addition, the zoogeographical records of Ligophorus spp. on the M. cephalus species complex are briefly reviewed and updated.

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

    USGS Publications Warehouse

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

    2005-01-01

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

  16. Molecular systematics of the gonorynchiform fishes (Teleostei) based on whole mitogenome sequences: implications for higher-level relationships within the Otocephala.

    PubMed

    Lavoué, Sébastien; Miya, Masaki; Inoue, Jun G; Saitoh, Kenji; Ishiguro, Naoya B; Nishida, Mutsumi

    2005-10-01

    Although the order Gonorynchiformes includes only 31 species assigned to seven genera and four families, it exhibits a large variety of anatomical structures, making difficult the reconstruction of phylogenetic relationships among its representatives. Within the basal teleosts, the Gonorynchiformes belong to the Otocephala where they have been alternatively placed as the sister group of the Otophysi and of the Clupeiformes. In this context, we investigated the phylogeny of the Gonorynchiformes using whole mitogenome sequences from 40 species (six being newly determined for this study). Our taxonomic sampling included at least one species of each gonorynchiform genus and of each other major otocephalan lineage. Unambiguously aligned, concatenated mitogenomic sequences (excluding the ND6 gene and control region) were divided into five partitions (1st, 2nd, and 3rd codon positions, tRNA genes, and rRNA genes) and partitioned Bayesian analyses were conducted. The resultant phylogenetic trees were fully resolved, with most of the nodes well supported by the high posterior probabilities. As expected, the Otocephala were recovered as monophyletic. Within this group, the mitogenome data supported the monophyly of Alepocephaloidei, Gonorynchiformes, Otophysi, and Clupeiformes. The Gonorynchiformes and the Otophysi formed a sister group, rending the Ostariophysi monophyletic. This result conflicts with previous mitogenomic phylogenetic studies, in which a sister relationship was found between Clupeiformes and Gonorynchiformes. We discussed the possible causes of this incongruence. Within the Gonorynchiformes, the following original topology was found: (Gonorynchus (Chanos (Phractolaemus (Cromeria (Grasseichthys (Kneria, Parakneria)))))). We confirmed that the paedomorphic species Cromeria nilotica and Grasseichthys gabonensis belong to the family Kneriidae; however, the two species together did not form a monophyletic group. This result challenges the value of reductive or absent characters as synapomorphies in this group.

  17. Karyotypic diversity and evolutionary trends in the Neotropical catfish genus Hypostomus Lacépède, 1803 (Teleostei, Siluriformes, Loricariidae)

    PubMed Central

    Alves, Anderson Luis; de Borba, Rafael Splendore; Oliveira, Claudio; Mauro Nirchio; Granado, Angel; Foresti, Fausto

    2012-01-01

    Abstract The family Loricariidae with 813 nominal species is one of the largest fish families of the world. Hypostominae, its more complex subfamily, was recently divided into five tribes. The tribe Hypostomini is composed of a single genus, Hypostomus Lacépède, 1803, which exhibits the largest karyotypic diversity in the family Loricariidae. With the main objective of contributing to a better understanding of the relationship and the patterns of evolution among the karyotypes of Hypostomus species, cytogenetic studies were conducted in six species of the genus from Brazil and Venezuela. The results show a great chromosome variety with diploid numbers ranging from 2n=68 to 2n=76, with a clear predominance of acrocentric chromosomes. The Ag-NORs are located in terminal position in all species analyzed. Three species have single Ag-NORs (Hypostomus albopunctatus (Regan, 1908), Hypostomus prope plecostomus (Linnaeus, 1758), and Hypostomus prope paulinus (Ihering, 1905)) and three have multiple Ag-NORs (Hypostomus ancistroides (Ihering, 1911), Hypostomus prope iheringi (Regan, 1908), and Hypostomus strigaticeps (Regan, 1908)). In the process of karyotype evolution of the group, the main type of chromosome rearrangements was possibly centric fissions, which may have been facilitated by the putative tetraploid origin of Hypostomus species. The relationship between the karyotype changes and the evolution in the genus is discussed. PMID:24260683

  18. Life history of roach, Rutilus rutilus (Cyprinidae, Teleostei). A qualitative and quantitative study on the development of sensory brain areas.

    PubMed

    Brandstätter, R; Kotrschal, K

    1989-01-01

    The present study deals with aspects of the brain development in the roach, Rutilus rutilus, a common mid-European cyprinid fish. The morphogenesis of selected brain areas from hatching to early juveniles was examined on serial paraffin cross-sections. From early juveniles to large adults, brain growth was quantitatively analyzed by computer-aided planimetry. The hatchlings of roach show a cytologically distinct optic tectum, but a poorly differentiated brainstem, reflecting the predominance of the optic sense during the larval planktivorous period. The differentiation and outgrowth of chemosensory brainstem centers is related to the onset and development of benthivorous feeding in juveniles. The optic tectum decreases in size relative to the total brain volume from juveniles through adults. The corpus cerebelli increases in relative size, whereas chemosensory and acousticolateral centers grow isometrically with the brain as a whole.

  19. Morphological and taxonomic descriptions of a new genus and species of killifishes (Teleostei: Cyprinodontiformes) from the high Andes of northern Chile

    PubMed Central

    Arratia, Gloria; Vila, Irma; Lam, Natalia; Guerrero, Claudia Jimena

    2017-01-01

    A new genus and species, Pseudorestias lirimensis, is described from the southern part of the Chilean Altiplano. While sharing several characters that clearly align the new species with Orestias, this new fish is characterized by numerous autapomorphies: the Meckel cartilage is a continuous cartilage that broadly expands posteriorly (in large specimens, it keeps its anterior part and is resorbed posteriorly), the basibranchials are fused into one long element, the second pharyngobranchial is not displaced dorsally over pharyngobranchial tooth plate 3+4, but they are aligned, the anterior and posterior ceratohyals are closely articulated keeping a scarce amount of cartilage between both bones and ventral to them, ossified middle and distal dorsal radials are present in females as well as ossified middle and distal anal radials. Pseudorestias lirimensis presents strong sexual dimorphism associated to size. Females are almost twice as large and long than males, neuromast lines are absent in males, a mesethmoid is present in males, squamation on head is reduced in males, and ossified middle and distal radial of dorsal fin are cartilaginous in males. Pseudorestias and Orestias are suggested as the sole members of the tribe Orestiini. A list of characters diagnosing the tribe is provided. The presence of the new genus is interpreted as a possible result of the ecosystem isolation where the fish is living from surrounding basins—as early as possibly from the Miocene-Pliocene times—and its physical and chemical characteristics. Small populations, living conditions, small habitat, and reduced distribution make this species a strong candidate to be considered critically endangered, a situation already established for all other Chilean species living in the Altiplano. There is high probability it will become extinct due to water demands and climate change in the region. PMID:28792510

  20. A review of the Pseudobarbus afer (Peters, 1864) species complex (Teleostei, Cyprinidae) in the eastern Cape Fold Ecoregion of South Africa.

    PubMed

    Chakona, Albert; Skelton, Paul H

    2017-01-01

    The Eastern Cape redfin, Pseudobarbus afer , has long been considered to be a single widespread and variable species occurring in multiple isolated river systems in the Cape Fold Ecoregion (CFE) at the southern tip of Africa. Mitochondrial cytochrome b and control region sequence data of individuals from populations currently assigned to Pseudobarbus afer across the species' distribution range revealed existence of four deeply divergent taxonomic units: (i) the Mandela lineage confined to the Sundays, Swartkops and Baakens river systems, (ii) the Krom lineage endemic to the Krom River system, (iii) the St Francis lineage occurring in the Gamtoos and adjacent river systems, and (iv) the Forest lineage occurring in several coastal river systems from the Tsitsikamma to the Klein Brak River system. The Forest lineage is closely related to Pseudobarbus phlegethon from the Olifants River system on the west coast of South Africa, suggesting that it does not belong to Pseudobarbus afer s.l. Herein we focus on the three lineages within the Pseudobarbus afer s.l. complex and provide new diagnosis for Pseudobarbus afer s.s (Mandela lineage), revalidate Pseudobarbus senticeps (Krom lineage) as a distinct species, and describe a new species Pseudobarbus swartzi (St Francis lineage). The three species exhibit subtle differences, which explains why they were previously considered to represent a single variable and widespread species. Pseudobarbus senticeps differs from both Pseudobarbus afer and Pseudobarbus swartzi by having fewer (i.e. larger) scales (25-33, mode 29 lateral line scale series; 10-12, mode 11 circumpeduncular scales) and presence of a lateral stripe which terminates in a conspicuous triangular blotch at the base of the caudal fin. Long barbels which reach or surpass the vertical through the posterior edge of the eye further separate Pseudobarbus senticeps from Pseudobarbus afer s.s. which possesses simple short barbels which do not reach the vertical through the posterior margin of the eye. Pseudobarbus afer s.s differs from Pseudobarbus swartzi sp. n. by possession of fewer scale rows along the lateral line (29-35, mode 32 vs 34-37, mode 36 in Pseudobarbus swartzi ), fewer scales around the caudal peduncle (12-16, mode 12 vs 13-17, mode 16 in Pseudobarbus swartzi ) and a distinct mesh or net-like pigmentation pattern on latero-ventral scales.

  1. Pethia aurea (Teleostei: Cyprinidae), a new species of barb from West Bengal, India, with redescription of P. gelius and P. canius.

    PubMed

    Knight, J D Marcus

    2013-01-01

    Fishes currently assigned to Pethia gelius Hamilton from West Bengal are shown to belong to a closely-related group of three species: P gelius, its erstwhile synonym P canius Hamilton and a new species, P aurea. The three species are distinguished from all other species of Pethia by having the lateral line incomplete, with 3-4 pored scales; 20-26 scales in lateral series on body; ½4-5/l/2-3½ scales in transverse line on body; 8-9 predorsal scales; barbels absent and by a unique colour pattern consisting of two or three black blotches on the body (which, however, fade on preservation), the first behind the opercle, the second beneath the origin of the dorsal fin, extending to the mid-lateral region, and the third above the origin of the anal fin. A black spot is also present at the base of the dorsal and anal fins. Additionally, P gelius is distinguished by having the last unbranched dorsal-fin ray thick, straight, serrated, with 20-25 serrae on its posterior margin; a snout length of 6.1-8.4% standard length (SL); a body depth of 32.6-37.7% SL; and a dorsal-fin height of 19.4-22.8% SL. Pethia canius is additionally distinguished by having a snout length of 8.9-11.8% SL; a body depth of 28.1-32.2% SL; and dorsal-fin height of 26.9-32.8% SL. Pethia aurea, new species, is additionally distinguished from all its congeners by having ½5/1/3-3½ scales in transverse line on body; 9 pre-dorsal scales; and last unbranched dorsal-fin ray slender, serrated, with 19-22 serrae on posterior margin.

  2. New observations on Myxozoa of the goldline sea bream Sarpa salpa L. 1758 (Teleostei : Sparidae) from the Mediterranean coast of Tunisia.

    PubMed

    Laamiri, Sayef

    2014-11-24

    A member of the Sparidae family, the goldline sea bream Sarpa salpa (Linnaeus, 1758) collected from the Gulf of Tunis and the Bay of Bizerte in Northeast Tunisia, Western Mediterranean, were examined for the myxozoan parasites. During the parasitological exposure, a total of 7 myxosporean are found including 6 coelozoic species belong to the genus Ceratomyxa Thélohan, 1892 infected the gallbladder of their host of which 3 known species have been previously described, C. arcuata Thélohan, 1892, C. pallida Thélohan, 1895 and C. herouardi Georgévitch, 1916 and 3 species seem different in morphology to Ceratomyxa spp already known from Mediterranean Sea or from other localities in the wide world. These species are Ceratomyxa sp. 1, Ceratomyxa sp. 2 and Ceratomyxa sp. 3. Only one histozoic species belongs to the genus Henneguya Thélohan, 1892, Henneguya sp. identified for the first time infecting the mesentery vessels of S. salpa. The myxosporean parasite C. arcuata Thélohan, 1892 is reported for the first time in Tunisian waters from the goldline sea bream which represents as new host records. In addition to the Monoparasitism, the phenomenon of Polyparasitism was observed between the current species in both sampling sites with two types: Biparasitism and Triparasitism. The most frequent Polyparasitism was a Biparasitism-type between C. herouardi and C. pallida with frequency 16.97%. For all the species, no serious pathogenic changes have been recorded in the host organ or in the outward appearance of the fish. Morphological features, site of infection into the host, parasite prevalence and mean intensity of each myxosporean found during this survey are determined and their taxonomic affinities to other species are discussed.

  3. [Hyphessobrycon taphorni and H. eschwartzae (Teleostei: Characidae) two new species of fish in the basin of Madre de Dios river, Peru].

    PubMed

    Garcia-Alzate, Carlos A; Romin-Valencia, César; Ortega, Hernán

    2013-06-01

    Hyphessobrycon with 129 valid species, is a genus of fish that has a great diversity of species in the Neotropical ichthyofauna, reaches its greatest diversity in the Amazon basin with about 70% of these species, is highly desired by hobbyists because of their beauty and color, and are still meeting new species. We analyzed specimens from the Departamento de Ictiología, Museo de Historia Natural de la Universidad Mayor de San Marcos, Lima, Perú (MUSM); and measurements of the specimens were taken point to point with digital calipers. Observations of bone and cartilage structures were made on cleared and stained (C&S) samples. The morphometric relationships between species using 21 variables were explored using a principal component analysis (PCA). Here we describe two new species, Hyphessobrycon taphorni and H. eschwartzae from the Madre de Dios River drainage, Peru. Hyphessobrycon taphorni sp. n. can be distinguished by the number of dorsal-fin rays (iii, 8), by the number of: pored lateral-line scales (4-5), teeth in the outer premaxillary row (1-2), teeth in the inner premaxillary row (7-8), by: the caudal-peduncle length (11.4-16.4% SL), number of lateral scales (28-29, except from H. loretoensis which has 29-30) and absence of a humeral spot (vs. present), it differs from H. loretoensis by the number of: scales between the lateral line and the anal fin origin (4 vs. 3) and maxillary teeth (2 vs. 3-4), and it differs from H. agulha by the number of branched pectoral-fin rays (11-12 vs. 9-10). Hyphessobrycon eschwartzae sp. n. is distinguished by the number of: simple anal-fin rays (iv), teeth on the dentary (13-15), teeth in the inner premaxillary row (6), teeth in the outer premaxillary row (3, except from H. heterorhabdus and H. loretoensis which have 3-4); it differs from H. loretoensis by the number of: pored lateral-line scales (7 vs. 9-10), scales between the lateral line and the dorsal-fin origin (5 vs. 3-4); it differs from H. agulha in the number of lateral scales (30-31 vs. 33-34), by the number of: predorsal scales (9 vs. 10), maxillary teeth (4 vs. 0-1); in having in life a red lateral stripe above the dark lateral stripe that extends from the posterior part of the opercle to the caudal peduncle (vs. absent) and by the presence of bony hooks in mature males only on the anal fin (vs. hooks on all fins, including the caudal).

  4. Variation in thermal tolerance and routine metabolism among spring- and stream-dwelling freshwater sculpins (Teleostei: Cottidae) of the southeastern United States

    USGS Publications Warehouse

    Walsh, S.J.; Haney, D.C.; Timmerman, C.M.

    1997-01-01

    Evolutionary theory predicts that some aquatic organisms may adapt by directional selection to limiting physical environmental conditions, yet empirical data are conflicting. We sought to test the assumption that sculpins (family Cottidae) inhabiting thermally stable springs of the southeastern United States differ in temperature tolerance and metabolism from populations inhabiting more thermally labile stream habitats. Spring populations of pygmy sculpins (Coitus pygmaeus) and Ozark sculpins (C. hypselurus) differed interspecifically in thermal tolerance from populations of stream-dwelling mottled (C. bairdi) and Tallapoosa sculpins (C. tallapoosae), and both stream and spring populations of banded sculpins (C. carolinae). No intra- or interspecific differences in thermal tolerance were found among populations of C. bairdi, C. tallapoosae, or C. carolinae. Coitus pygmaeus acclimated to 15??C differed intraspecifically in routine metabolism from fish acclimated to 20?? and 25??C. Cottus pygmaeus and stream-dwelling C. bairdi and C. carolinae acclimated to temperatures of 20?? and 25??C showed no interspecific differences in routine metabolism. Our results suggest that some spring-adapted populations or species may be more stenothermal than stream-dwelling congeners, but a greater understanding of the interactions of other physical and biological factors is required to better explain micro- and macrohabitat distributions of eastern North American sculpins.

  5. Morphometric or morpho-anatomal and genetic investigations highlight allopatric speciation in Western Mediterranean lagoons within the Atherina lagunae species (Teleostei, Atherinidae)

    NASA Astrophysics Data System (ADS)

    Trabelsi, M.; Maamouri, F.; Quignard, J.-P.; Boussaïd, M.; Faure, E.

    2004-12-01

    Current distribution of Atherina lagunae poses an interesting biogeographical problem as this species inhabits widely separate circum-Mediterranean lagoons. Statistical analyses of 87 biometric parameters and genetic variation in a portion of the cytochrome b gene were examined in four populations of A. lagunae from Tunisian and French lagoons. The results suggested a subdivision into two distinct Atherinid groups: one included the French lagoonal sand smelts and the second included the Tunisian ones. Tunisian lagoonal sand smelts were distinguished from the French ones by the lower number of lateral line scales, vertebrae, pectorals and first dorsal fin rays and the higher number of lower and total gillrakers. In addition, A. lagunae from Tunisian lagoons are characterised by short preorbital length, developed operculum, broad interorbital space, larger head, robust body and a relatively small first dorsal fin which is positioned backwards. In addition, intraspecific sequence variation in a portion of the cytochrome b gene was examined in 87 individuals from Tunisia and France. The high correlation between the results of the molecular phylogenetic tree and biometric statistical data analysis suggested that two different sibling species or at least sub-species or semi-species have colonised the lagoons. In addition, our analyses suggested that the evolution of A. lagunae probably occurred in two steps including marine sympatric speciation within the large Atherina boyeri complex and a post-Pleistocene colonisation of the lagoons.

  6. Henneguya melini n. sp. (Myxosporea: Myxobolidae), a parasite of Corydoras melini (Teleostei: Siluriformes) in the Amazon region: morphological and ultrastructural aspects.

    PubMed

    Mathews, Patrick D; Maia, Antônio A M; Adriano, Edson A

    2016-09-01

    A new species of myxozoan, Henneguya melini sp. n. (Myxosporea: Myxobolidae), was described based on morphologic and ultrastructural features. This is a parasite of the ornamental freshwater fish C. melini from the Rio Negro, and it was found in five of 30 (16.7 %) C. melini examined. The parasite was found in the gill filaments, and the plasmodia had form of round to ellipsoid, with mature and immature spores inside them. The average spore body was 15.5 ± 0.2 μm in length, 4.7 ± 0.1 μm in width, and the tail measured 25.3 ± 0.1 μm in length. The spores showed typical features of the genus Henneguya, with two valves of equal size and two symmetrical polar capsules of 4.8 ± 0.7 μm in length and 1.7 ± 0.3 μm in width. Each polar capsule had a polar filament with five to six turns. Based on morphology (morphologic and ultrastructural data) of the plasmodia and spores and the fact that this is the first report of a Henneguya species in a fish species of the genus Corydoras, it was considered a new myxozoan species.

  7. The presence and expression of the HIF-1α in the respiratory intestine of the bronze Corydoras Corydoras aeneus (Callichthyidae Teleostei).

    PubMed

    Satora, Leszek; Mytych, Jennifer; Bilska-Kos, Anna

    2018-05-23

    Bronze corydoras (Corydoras aeneus) is a small diurnal activity fish from South America. Under hypoxia conditions, it uses the posterior part of the intestine as an accessory respiratory organ. The present PCR studies demonstrated higher expression of HIF-1α (hypoxia-inducible factor) gene in the respiratory than that in digestive part of bronze corydoras intestine. Further, immunolocalization studies using antibodies specific to HIF-1α and transmission electron microscopy (TEM) revealed the presence of HIF-1α epitopes in the intestine of Corydoras aeneus. In the respiratory intestine, the numerous clusters of gold particles visualizing HIF-1α antibody were observed within fibroblasts, whereas in the digestive tract of this species, single gold grains in the epithelial cells were noted. On the other hand, the presence of HIF-1α and the cytoplasmic domain of the epidermal growth factor receptor (EGFR) in the respiratory intestine of bronze corydoras assumes their interactions in the system where these factors appeared for the first time. The non-obligatory air-breathing fishes using their digestive tract as an accessory respiratory organ during hypoxia conditions are very interesting for the studies of the processes that control HIF-1α expression and squamous cell proliferation.

  8. Molecular systematics and distribution review of the endemic cyprinid species, Persian chub, Acanthobrama persidis (Coad, 1981) in Southern Iran (Teleostei: Cyprinidae)

    PubMed Central

    Teimori, Azad; Esmaeili, Hamid Reza; Sayyadzadeh, Golnaz; Zarei, Neda; Gholamhosseini, Ali

    2015-01-01

    The Iranian Persian chub is an endemic species of the family Cyprinidae known only from few localities in drainages of Southern Iran. It was originally described in the genus Pseudophoxinus as (Pseudophoxinus persidis) and then Petroleuciscus (as Petroleuciscus persidis). In this study, we examined phylogenetic relationships of the Iranian Persian chub with other relatives in the family Cyprinidae based on the mitochondrial cytochrome b gene to estimate the phylogenetic (and taxonomic) position of the species. Our molecular phylogenies show that new fish sequences from the drainages in southern Iran are clustered with sequences of the genus Acanthobrama from GenBank while the sequences from two other genera (Pseudophoxinus and Petroleuciscus) are in distinct clade. Therefore, we conclude that the populations of Persian Chub in drainages of southern Iran (i.e., Kol, Kor, Maharlu and Persis) belong to the genus Acanthobrama and species Acanthobrama persidis. The predicted geographic distributions for the species showed a large area of suitable climate for A. persidis across south and west of Iran especially in the Kor River basin. Some other parts in the Persis and Tigris are also might have been suitable habitats for this cyprinid species showing possible dispersal route of Acanthobrama from Tigris to the Persis, Kor and Kol basins. PMID:27844011

  9. Modifications of the falciform process in the eye of beloniformes (Teleostei: Atherinomorpha): evolution of a curtain-like septum in the eye.

    PubMed

    Reckel, Frank; Melzer, Roland R

    2004-04-01

    In order to comparatively analyze curtain-like septa in the eyes of visually orientated "close-to-surface-predators" among atherinomorph teleosts, we examined the eyes of 24 atherinomorph species under a binocular microscope with regard to the falciform process and related structures in the vitreous cavity. Additionally, falciform process samples were analyzed by transmission electron microscopy. All the studied representatives of the Cyprinodontiformes and Atheriniformes, and of one of the beloniform suborder, Adrianichthyioidei, possess a "typical" processus falciformis. In the eyes of the representatives of the other beloniform suborder, Belonoidei, however, pigmented structures that originate in the region of the optic disc and protrude into the vitreous cavity were noted. In the Hemiramphidae (halfbeaks) and Exocoetidae (flying fishes) these pigmented structures have a more cone-like shape, whereas in the Belonidae (needlefishes) and Scomberesocidae (sauries) horizontally oriented heavily pigmented curtain-like septa occur that divide the vitreous cavity dorsoventrally. It is suggested that the "typical" processus falciformis represents a plesiomorphic feature within the Atherinomorpha, whereas the pigmented modifications of the falciform process must be seen as a synapomorphic character state of the Belonoidei. The curtain-like septum of the Belonidae and Scomberesocidae might have evolved from the cone-like structures that are found in the Exocoetoidea. The functional significance of the pigmented structures in the eye is as yet not clear, except for the curtain-like septum found in Belonidae. It might play a role in visual orientation near the water surface at Snell's window. Copyright 2004 Wiley-Liss, Inc.

  10. A new genus and species of blind sleeper (Teleostei: Eleotridae) from Oaxaca, Mexico: First obligate cave gobiiform in the Western Hemisphere

    USGS Publications Warehouse

    Walsh, Stephen J.; Chakrabarty, Prosanta

    2016-01-01

    Caecieleotris morrisi, new genus and species of sleeper (family Eleotridae), is described from a submerged freshwater cave in a karst region of the northern portion of the State of Oaxaca, Mexico, Río Papaloapan drainage, Gulf of Mexico basin. The new species represents the first cave-adapted sleeper known from the Western Hemisphere and is one of only 13 stygobitic gobiiforms known worldwide, with all others limited in distribution to the Indo-Pacific region. The new taxon represents a third independent evolution of a hypogean lifestyle in sleepers, the others being two species ofOxyeleotris (O. caeca and O. colasi) from New Guinea and a single species, Bostrychus microphthalmus, from Sulawesi. Caecieleotris morrisi, new species, is distinguished from epigean eleotrids of the Western Atlantic in lacking functional eyes and body pigmentation, as well as having other troglomorphic features. It shares convergent aspects of morphology with cave-dwelling species of Oxyeleotris and B. microphthalmus but differs from those taxa in lacking cephalic pores and head squamation, among other characters. Description of C. morrisi, new species, brings the total number of eleotrid species known from Mexico to 12. Seven of these, including the new species, occur on the Atlantic Slope.

  11. Effects of climatic and geological processes during the pleistocene on the evolutionary history of the northern cavefish, Amblyopsis spelaea (teleostei: amblyopsidae).

    PubMed

    Niemiller, Matthew L; McCandless, James R; Reynolds, R Graham; Caddle, James; Near, Thomas J; Tillquist, Christopher R; Pearson, William D; Fitzpatrick, Benjamin M

    2013-04-01

    Climatic and geological processes associated with glaciation cycles during the Pleistocene have been implicated in influencing patterns of genetic variation and promoting speciation of temperate flora and fauna. However, determining the factors promoting divergence and speciation is often difficult in many groups because of our limited understanding of potential vicariant barriers and connectivity between populations. Pleistocene glacial cycles are thought to have significantly influenced the distribution and diversity of subterranean invertebrates; however, impacts on subterranean aquatic vertebrates are less clear. We employed several hypothesis-driven approaches to assess the impacts of Pleistocene climatic and geological changes on the Northern Cavefish, Amblyopsis spelaea, whose current distribution occurs near the southern extent of glacial advances in North America. Our results show that the modern Ohio River has been a significant barrier to dispersal and is correlated with patterns of genetic divergence. We infer that populations were isolated in two refugia located north and south of the Ohio River during the most recent two glacial cycles with evidence of demographic expansion in the northern isolate. Finally, we conclude that climatic and geological processes have resulted in the formation of cryptic forms and advocate recognition of two distinct phylogenetic lineages currently recognized as A. spelaea. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  12. Phylogenetic analysis of molecular and morphological data highlights uncertainty in the relationships of fossil and living species of Elopomorpha (Actinopterygii: Teleostei).

    PubMed

    Dornburg, Alex; Friedman, Matt; Near, Thomas J

    2015-08-01

    Elopomorpha is one of the three main clades of living teleost fishes and includes a range of disparate lineages including eels, tarpons, bonefishes, and halosaurs. Elopomorphs were among the first groups of fishes investigated using Hennigian phylogenetic methods and continue to be the object of intense phylogenetic scrutiny due to their economic significance, diversity, and crucial evolutionary status as the sister group of all other teleosts. While portions of the phylogenetic backbone for Elopomorpha are consistent between studies, the relationships among Albula, Pterothrissus, Notacanthiformes, and Anguilliformes remain contentious and difficult to evaluate. This lack of phylogenetic resolution is problematic as fossil lineages are often described and placed taxonomically based on an assumed sister group relationship between Albula and Pterothrissus. In addition, phylogenetic studies using morphological data that sample elopomorph fossil lineages often do not include notacanthiform or anguilliform lineages, potentially introducing a bias toward interpreting fossils as members of the common stem of Pterothrissus and Albula. Here we provide a phylogenetic analysis of DNA sequences sampled from multiple nuclear genes that include representative taxa from Albula, Pterothrissus, Notacanthiformes and Anguilliformes. We integrate our molecular dataset with a morphological character matrix that spans both living and fossil elopomorph lineages. Our results reveal substantial uncertainty in the placement of Pterothrissus as well as all sampled fossil lineages, questioning the stability of the taxonomy of fossil Elopomorpha. However, despite topological uncertainty, our integration of fossil lineages into a Bayesian time calibrated framework provides divergence time estimates for the clade that are consistent with previously published age estimates based on the elopomorph fossil record and molecular estimates resulting from traditional node-dating methods. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Two new species and a new subgenus of toothed Brachyhypopomus electric knifefishes (Gymnotiformes, Hypopomidae) from the central Amazon and considerations pertaining to the evolution of a monophasic electric organ discharge

    PubMed Central

    Sullivan, John P.; Zuanon, Jansen; Cox Fernandes, Cristina

    2013-01-01

    Abstract We describe two new, closely related species of toothed Brachyhypopomus (Hypopomidae: Gymnotiformes: Teleostei) from the central Amazon basin and create a new subgenus for them. Odontohypopomus, new subgenus of Brachyhypopomus, is diagnosed by (1) small teeth present on premaxillae; (2) medialmost two branchiostegal rays thin with blades oriented more vertically than remaining three rays; (3) background color in life (and to lesser extent in preservation) distinctly yellowish with head and sides peppered with small, widely spaced, very dark brown stellate chromatophores that greatly contrast with light background coloration; (4) a dark blotch or bar of subcutaneous pigment below the eye; (5) electric organ discharge waveform of very long duration (head-positive phase approx. 2 milliseconds or longer, head-negative phase shorter or absent) and slow pulse repetition rate (3–16 Hz). The type species of the new subgenus, Brachyhypopomus (Odontohypopomus) walteri sp. n., is diagnosed by the following additional character states: (1) subcutaneous dark pigment at base of orbit particularly prominent, (2) body semi-translucent and nearly bright yellow background coloration in life, (3) a biphasic electric organ discharge (EOD) waveform of very long duration (between 3.5 and 4 milliseconds at 25° C) with head-positive first phase significantly longer than second head-negative phase in both sexes. Brachyhypopomus (Odontohypopomus) bennetti sp. n. is diagnosed by two character states in addition to those used to diagnose the subgenus Odontohypopomus: (1) a deep electric organ, visible as large semi-transparent area, occupying approximately 14–17% body depth directly posterior to the abdominal cavity in combination with a short, but deep, caudal filament, and (2) a monophasic, head-positive EOD waveform, approximately 2.1 milliseconds in duration in both sexes. These are the only described rhamphichthyoid gymnotiforms with oral teeth, and Brachyhypopomus bennetti

  14. Two new species and a new subgenus of toothed Brachyhypopomus electric knifefishes (Gymnotiformes, Hypopomidae) from the central Amazon and considerations pertaining to the evolution of a monophasic electric organ discharge.

    PubMed

    Sullivan, John P; Zuanon, Jansen; Cox Fernandes, Cristina

    2013-01-01

    We describe two new, closely related species of toothed Brachyhypopomus (Hypopomidae: Gymnotiformes: Teleostei) from the central Amazon basin and create a new subgenus for them. Odontohypopomus, new subgenus of Brachyhypopomus, is diagnosed by (1) small teeth present on premaxillae; (2) medialmost two branchiostegal rays thin with blades oriented more vertically than remaining three rays; (3) background color in life (and to lesser extent in preservation) distinctly yellowish with head and sides peppered with small, widely spaced, very dark brown stellate chromatophores that greatly contrast with light background coloration; (4) a dark blotch or bar of subcutaneous pigment below the eye; (5) electric organ discharge waveform of very long duration (head-positive phase approx. 2 milliseconds or longer, head-negative phase shorter or absent) and slow pulse repetition rate (3-16 Hz). The type species of the new subgenus, Brachyhypopomus (Odontohypopomus) walteri sp. n., is diagnosed by the following additional character states: (1) subcutaneous dark pigment at base of orbit particularly prominent, (2) body semi-translucent and nearly bright yellow background coloration in life, (3) a biphasic electric organ discharge (EOD) waveform of very long duration (between 3.5 and 4 milliseconds at 25° C) with head-positive first phase significantly longer than second head-negative phase in both sexes. Brachyhypopomus (Odontohypopomus) bennetti sp. n. is diagnosed by two character states in addition to those used to diagnose the subgenus Odontohypopomus: (1) a deep electric organ, visible as large semi-transparent area, occupying approximately 14-17% body depth directly posterior to the abdominal cavity in combination with a short, but deep, caudal filament, and (2) a monophasic, head-positive EOD waveform, approximately 2.1 milliseconds in duration in both sexes. These are the only described rhamphichthyoid gymnotiforms with oral teeth, and Brachyhypopomus bennetti is the first

  15. Comparison of the oropharyngeal cavity in the Starksiini (Teleostei: Blenniiformes: Labrisomidae): taste buds and teeth, including a comparison with closely-related genera.

    PubMed

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

    2012-06-01

    The present study describes the distribution of taste buds and teeth in the oropharyngeal cavity of 13 species of adult (18-60 mm SL) Starksiini fishes inhabiting subtidal waters of the Neotropical region. Four types of taste buds described previously in other fish groups were observed within the oropharyngeal cavity, of which type I, situated on prominent protruding papillae, is the most common. The number of taste buds in this cavity varies considerably, ranging from ca. 202 in Starksia lepicoelia to ca. 770 in S. sluiteri. In all the studied species, taste buds are more numerous on the posterior (160-396) than on the anterior (42-294) part of the oropharyngeal cavity. The presence of different numbers of taste buds in different Starksiini species of the same standard length suggests that numbers of taste buds are not directly correlated with size and may be species-specific. Teeth are found on the premaxilla, dentary, vomer, palatine (in some species) and the upper and lower pharyngeal jaws (third pharyngobranchials and fifth ceratobranchials, respectively); the form and number of teeth and taste buds on each of these sites differs among the various species of Starksiini and between them and closely related species of the labrisomid tribes Labrisomini, Mnierpini, and Paraclinini. The results thus suggest potential systematic value in certain features of the oropharyngeal cavity for blenniiform fishes. It is also shown that benthic-feeding omnivorous fishes have higher densities of taste buds than piscivorous fishes. A possible correlation among numbers of taste buds, their positions in the oropharyngeal cavity, and other parameters is discussed. Copyright © 2012 Wiley Periodicals, Inc.

  16. Salmo kottelati, a new species of trout from Alakır Stream, draining to the Mediterranean in southern Anatolia, Turkey (Teleostei, Salmonidae)

    PubMed Central

    Turan, Davut; Doğan, Esra; Kaya, Cüneyt; Kanyılmaz, Mahir

    2014-01-01

    Abstract Salmo kottelati sp. n., is described from Alakır Stream (Mediterranean basin) in Turkey. It is distinguished from other Anatolian Salmo species by a combination of the following characters (none unique to the species): general body colour greenish to silvery in life; 7–9 parr marks along lateral line; four dark bands on flank absent in both sexes; black ocellated spots few, present only on upper part of flank in individuals smaller than 160 mm SL but in larger both males and females black spots numerous and located on back and middle and upper part of flank; red spots few to numerous, scattered on median, and half of lower and upper part of flank; head long (length 29–33% SL in males, 26–32 in females); mouth large (length of mouth gape 13–19% SL in males, 12–15 in females); maxilla long (length 10–13% SL in males, 8–12 in females); 105–113 lateral line scales; 24–29 scale rows between lateral line and dorsal-fin origin, 17–19 scale rows between lateral line and anal-fin origin; 13–15 scales between lateral line and adipose-fin insertion. PMID:25589858

  17. Generic assignment of Leuciscus kurui Bogutskaya from the upper Tigris drainage, and a replacement name for Alburnus kurui Mangit Yerli (Teleostei: Leuciscidae).

    PubMed

    Freyhof, JÖrg; Kaya, CÜneyt; BayÇelebİ, Esra; Geiger, Matthias; Turan, Davut

    2018-04-16

    The generic position of Leuciscus kurui Bogutskaya, 1995 is reviewed through a comparison of morphological and molecular characters (COI). The molecular data place L. kurui in Alburnus, close to Alburnus timarensis from the Lake Van basin. Alburnus kurui (Bogutskaya) is distinguished from this species by lacking a ventral keel and possessing both a very low number of gill rakers and midlateral scales. Alburnus selcuklui, from the upper Tigris drainage, cannot be distinguished from the widespread A. sellal and is therefore treated as a synonym of this species. Alburnus kurui Mangit Yerli, 2018 is a junior secondary homonym of A. kurui (Bogutskaya, 1995) and A. carianorum is proposed as its replacement name. Several specimens of Alburnus caeruleus and Alburnus heckeli shared the same haplotypes as some A. sellal and therefore these species cannot always be distinguished by mitochondrial molecular characters. Alburnus caeruleus and A. heckeli are treated as valid species. Other individuals of A. caeruleus have haplotypes very different from A. sellal, and A. heckeli is well distinguished from A. sellal by having more gill rakers. The Lake Van basin as a separate freshwater ecoregion and the treatment of several species of Alburnus in synonymy of A. mento are discussed.

  18. The taxonomic placement of three fossil Fundulus species and the timing of divergence within the North American topminnows (Teleostei: Fundulidae).

    PubMed

    Ghedotti, Michael J; Davis, Matthew P

    2017-04-10

    The fossils species †Fundulus detillae, †F. lariversi, and †F. nevadensis from localities in the western United States are represented by well-preserved material with date estimations. We combined morphological data for these fossil taxa with morphological and DNA-sequence data to conduct a phylogenetic analysis and a tip-based divergence-time estimation for the family Fundulidae. The resultant phylogeny is largely concordant with the prior total-evidence phylogeny. The fossil species do not form a monophyletic group, and do not represent a discrete western radiation of Fundulus as previously proposed. The genus Fundulus diverged into subgeneric clades likely in the Eocene or Oligocene (mean age 34.6 mya, 53-23 mya), and all subgeneric and most species-group clades had evolved by the middle Miocene. †Fundulus lariversi is a member of subgenus Fundulus in which all extant species are found only in eastern North America, demonstrating that fundulids had a complicated biogeographic history. We confirmed †Fundulus detillae as a member of the subgenus Plancterus. †F. nevadensis is not classified in a subgenus but likely is related to the subgenera Plancterus and Wileyichthys.

  19. From the inside out: a new species of armoured catfish Corydoras with the description of poorly-explored character sources (Teleostei, Siluriformes, Callichthyidae).

    PubMed

    Espíndola, V C; Tencatt, L F C; Pupo, F M; Villa-Verde, L; Britto, M R

    2018-05-01

    A new species of the armoured catfish genus Corydoras is described from the Xingu-Tapajos ecoregion, Brazilian Amazon. The new species can be distinguished from its congeners by having the following combination of features: short mesethmoid, with anterior tip poorly developed, smaller than 50% of bone length; posterior margin of pectoral spine with serrations directed towards spine tip or perpendicularly oriented; infraorbital 2 only in contact with sphenotic; ventral laminar expansion of infraorbital 1 poorly or moderately developed; flank midline covered by small dark brown or black saddles with similar size to remaining markings on body; relatively larger, scarcer and more sparsely distributed dark brown or black spots on body; absence of stripe on flank midline; caudal fin with conspicuous dark brown or black spots along its entire surface; slender body; and strongly narrow frontals. A more comprehensive description of poorly-explored internal character sources, such as the gross morphology of the brain, Weberian apparatus and swimbladder capsule elements is presented. © 2018 The Fisheries Society of the British Isles.

  20. Seahorses of the Hippocampus coronatus complex: taxonomic revision, and description of Hippocampus haema, a new species from Korea and Japan (Teleostei, Syngnathidae).

    PubMed

    Han, Sang-Yun; Kim, Jin-Koo; Kai, Yoshiaki; Senou, Hiroshi

    2017-01-01

    Morphological and molecular analyses were conducted on 182 specimens belonging to the Hippocampus coronatus complex ( H. coronatus sensu lato), collected in Korea and Japan 1933-2015, in order to clarify the taxonomic status of the species within this complex. Three species are recognized based on the shape of the coronet, the number of trunk rings (TrR) and tail rings (TaR), and presence or absence of a wing-tip spine (WS) at the dorsal fin base. Hippocampus coronatus Temminck & Schlegel, 1850 ( H. coronatus sensu stricto), is diagnosed by 10 TrR, 37-40 TaR, an extremely high coronet (55.7-79.0 % head length) with four tips on the corona flat (CoT), and one WS. Hippocampus sindonis Jordan & Snyder, 1901 is diagnosed by 10 TrR, 35-38 TaR, a moderately high coronet (36.3-55.4 % HL) with five CoT, and no WS. A new species, H. haema is described on the basis of 140 specimens, characterized by 10 TrR, 35-38 TaR, a moderately high coronet (34.1-54.9 % head length) with four CoT, and two WS. Hippocampus haema is only known from the Korea Strait, western Kyushu, and East/Japan Sea. Recognition of the three species is supported by differences in mitochondrial DNA fragments (cytochrome b , 16S rRNA, and 12S rRNA).

  1. A new monozoic tapeworm, Lobulovarium longiovatum n. g., n. sp. (Cestoda: Caryophyllidea), from barbs Puntius spp. (Teleostei: Cyprinidae) in the Indomalayan region.

    PubMed

    Oros, Mikuláš; Ash, Anirban; Brabec, Jan; Kar, Pradip Kumar; Scholz, Tomáš

    2012-09-01

    A new caryophyllidean cestode is described from barbs Puntius spp. (Cypriniformes: Cyprinidae), with P. sophore (Hamilton) as its type-host, in the Ganges and Brahmaputra river basins in India and Bangladesh, and a new genus, Lobulovarium n. g., is proposed to accommodate it. The genus belongs to the Lytocestidae because its vitelline follicles are situated in the cortex. It is typified by: (i) a peculiar ovary, which is roughly H-shaped, but with asymmetrical, irregular lobes on its ventral and dorsal sides; (ii) an extensive vitellarium formed by numerous vitelline follicles scattered throughout the cortex; (iii) a long, conical postovarian part of the body with numerous vitelline follicles; (iv) a broadly digitate scolex with a slightly protrusible central cone; (v) a single gonopore (male and female genital ducts open via a single pore and a common genital atrium is absent); and (vi) a small number of testes (< 60). Molecular data (partial sequences of the lsrDNA) indicate that Lobulovarium longiovatum n. sp. belongs among the most basal caryophyllidean cestodes, being unrelated to species from siluriform catfishes in the Indomalayan region. Paracaryophyllaeus osteobramensis (Gupta & Sinha, 1984) Hafeezullah, 1993 (syn. Pliovitellaria osteobramensis Gupta & Sinha, 1984) from another cyprinid fish, Osteobrama cotio (Hamilton), in Uttar Pradesh, India, is tentatively transferred to Lobulovarium as L. osteobramense (Gupta & Sinha, 1984) n. comb. It differs from L. longiovatum by having much smaller eggs (length <50 μm versus >90 μm in L. longiovatum), which are spherical (length/width ratio 1:1 versus 2.5-3:1 in the new species), and the presence of vitelline follicles alongside the ovarian lobes (almost completely absent in L. longiovatum).

  2. Repeatability of clades as a criterion of reliability: a case study for molecular phylogeny of Acanthomorpha (Teleostei) with larger number of taxa.

    PubMed

    Chen, Wei-Jen; Bonillo, Céline; Lecointre, Guillaume

    2003-02-01

    Although much progress has been made recently in teleostean phylogeny, relationships among the main lineages of the higher teleosts (Acanthomorpha), containing more than 60% of all fish species, remain poorly defined. This study represents the most extensive taxonomic sampling effort to date to collect new molecular characters for phylogenetic analysis of acanthomorph fishes. We compiled and analyzed three independent data sets, including: (i) mitochondrial ribosomal fragments from 12S and 16s (814bp for 97 taxa); (ii) nuclear ribosomal 28S sequences (847bp for 74 taxa); and (iii) a nuclear protein-coding gene, rhodopsin (759bp for 86 taxa). Detailed analyses were conducted on each data set separately and the principle of taxonomic congruence without consensus trees was used to assess confidence in the results as follows. Repeatability of clades from separate analyses was considered the primary criterion to establish reliability, rather than bootstrap proportions from a single combined (total evidence) data matrix. The new and reliable clades emerging from this study of the acanthomorph radiation were: Gadiformes (cods) with Zeioids (dories); Beloniformes (needlefishes) with Atheriniformes (silversides); blenioids (blennies) with Gobiesocoidei (clingfishes); Channoidei (snakeheads) with Anabantoidei (climbing gouramies); Mastacembeloidei (spiny eels) with Synbranchioidei (swamp-eels); the last two pairs of taxa grouping together, Syngnathoidei (aulostomids, macroramphosids) with Dactylopteridae (flying gurnards); Scombroidei (mackerels) plus Stromatoidei plus Chiasmodontidae; Ammodytidae (sand lances) with Cheimarrhichthyidae (torrentfish); Zoarcoidei (eelpouts) with Cottoidei; Percidae (perches) with Notothenioidei (Antarctic fishes); and a clade grouping Carangidae (jacks), Echeneidae (remoras), Sphyraenidae (barracudas), Menidae (moonfish), Polynemidae (threadfins), Centropomidae (snooks), and Pleuronectiformes (flatfishes).

  3. Contribution to the molecular systematics of the genus Capoeta from the south Caspian Sea basin using mitochondrial cytochrome b sequences (Teleostei: Cyprinidae)

    PubMed Central

    Zareian, Halimeh; Esmaeili, Hamid Reza; Heidari, Adeleh; Khoshkholgh, Majid Reza; Mousavi-Sabet, Hamed

    2016-01-01

    Traditionally, Capoeta populations from the southern Caspian Sea basin have been considered as Capoeta capoeta gracilis. Study on the phylogenetic relationship of Capoeta species using mitochondrial cytochrome b gene sequences show that Capoeta population from the southern Caspian Sea basin is distinct species and receive well support (posterior probability of 100%). Based on the tree topologies obtained from Bayesian and Maximum Likelihood methods, three main groups for the studied Capoeta were detected: Clade I) Capoeta trutta group (the Mesopotamian Capoeta group) including closely related taxa (e.g. trutta, turani, barroisi) characterized by having numerous irregular black spots on the dorsal half of the body. This clade was the sister group to all other Capoeta species and its separation occurred very early in evolution possess, so we considered it as O ld Evolutionary Group. Clade II) comprises highly diversified and widespread group, Capoeta damascina complex group (small scale capoeta group), the Anatolian-Iranian group (e.g. banarescui, buhsei, damascina, saadii), characterized by small scales and plain body (absence of irregular black spots on the dorsal half of the body, except in some juveniles) with significantly later speciation event so called Young Evolutionary Group. Clade III) Capoeta capoeta complex group (large scale capoeta group, the Aralo-Caspian group) comprises very closely related taxa characterized by large scales and plain body (absence of irregular black spots on the dorsal half of the body) distributed in Aralo-Caspian water bodies (capoeta, ekmekciae, heratensis, gracilis, sevangi) that has been recently diverged and could be considered as Very Young Evolutionary Group. PMID:28097160

  4. Capoeta coadi, a new species of cyprinid fish from the Karun River drainage, Iran based on morphological and molecular evidences (Teleostei, Cyprinidae)

    PubMed Central

    Alwan, Nisreen H.; Zareian, Halimeh; Esmaeili, Hamid Reza

    2016-01-01

    Abstract As presently recognized, the genus Capoeta includes 24 species, nine of which are known to occur in Iran (Capoeta aculeata, Capoeta capoeta, Capoeta buhsei, Capoeta damascina, Capoeta fusca, Capoeta heratensis, Capoeta mandica, Capoeta saadii and Capoeta trutta) and are distributed in almost all Iranian basins except Sistan and Mashkid. Capoeta coadi sp. n. is a new species from the Karun River, southern Iran, draining into the Arvand Rud (Shatt al-Arab) which drains into the Persian Gulf. It is distinguished from all other species of Capoeta by the combination of the following characters: elongate and usually cylindrical body; 8–9 branched dorsal-fin rays; last unbranched dorsal-fin ray weakly to moderately ossified and serrated along 1/3–2/3 of its length; scales small; 70-84 in lateral line (total); 12–17 scales between dorsal-fin origin and lateral line; 9-11 scales between anal-fin origin and lateral line; 26–32 circum-peduncular scales; 10–13 gill rakers on lower limb of first gill arch; 45–47 total vertebrae; one posterior pair of barbels; bright golden-greenish or silvery body coloration in life; length of the longest dorsal-fin ray 15–22% SL; head length 23–26% SL; mouth width 7–10% SL. Capoeta coadi is also distinguished from all other congeners in the Iranian drainages by fixed diagnostic nucleotide substitutions in the mtDNA COI barcode region and cyt b. It is nested in the Capoeta damascina species complex. PMID:28050161

  5. A new species of freshwater eel-tailed catfish of the genus Tandanus (Teleostei: Plotosidae) from the Wet Tropics Region of Eastern Australia

    USGS Publications Warehouse

    Welsh, Stuart A.; Jerry, Dean R.; Burrows, Damien

    2014-01-01

    Tandanus tropicanus, new species, is described based on specimens from streams in the wet tropics region of northeast Queensland. Previously, two species were recognized in the genus Tandanus: T. tandanus of eastern Australia and T. bostocki of Western Australia. A combination of meristic and morphometric characters distinguishes the new species from all congeners. Further, taxonomic distinctness based on morphologic differences between the new species and all congeners is corroborated by genetic analyses.

  6. An experimental study on neural crest migration in Barbus conchonius (Cyprinidae, Teleostei), with special reference to the origin of the enteroendocrine cells.

    PubMed

    Lamers, C H; Rombout, J W; Timmermans, L P

    1981-04-01

    A neural crest transplantation technique is described for fish. As in other classes of vertebrates, two pathways of neural crest migration can be distinguished: a lateroventral pathway between somites and ectoderm, and a medioventral pathway between somites and neural tube/notochord. In this paper evidence is presented for a neural crest origin of spinal ganglion cells and pigment cells, and indication for such an origin is obtained for sympathetic and enteric ganglion cells and for cells that are probably homologues to adrenomedullary and paraganglion cells in the future kidney area. The destiny of neural crest cells near the developing lateral-line sense organs is discussed. When grafted into the yolk, neural crest cells or neural tube cells appear to differentiate into 'periblast cells'; this suggests a highly activating influence of the yolk. Many neural crest cells are found around the urinary ducts and, when grafted below the notochord, even within the urinary duct epithelium. These neural crest cells do not invade the gut epithelium, even when grafted adjacent to the developing gut. Consequently enteroendocrine cells in fish are not likely to have a trunk- or rhombencephalic neural crest origin. Another possible origin of these cells will be proposed.

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

    PubMed Central

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

    2011-01-01

    Abstract Conventional (Giemsa, C-Banding, Ag-NORs, CMA3) and molecular (5S rDNA, 18S rDNA, telomeric sequences) cytogenetic studies were carried out in specimens of ten distinct fish populations of the genus Gymnotus (Gymnotus sylvius Albert and Fernandes-Matioli, 1999, Gymnotus inaequilabiatus Valenciennes, 1839, Gymnotus pantherinus Steindachner, 1908, and G. cf. carapo Linnaeus, 1758) from different Brazilian hydrographic basins. Gymnotus sylvius presented a diploid number of 40 chromosomes (22m+12sm+6st), Gymnotus pantherinus presented 52 chromosomes (32m+18sm+2st), while Gymnotus inaequilabiatus (42m+10sm+2a)and Gymnotus cf. carapo (38m+12sm+4st) presented 54 chromosomes. The C-banding technique revealed centromeric marks in all chromosomes of all species. Besides that, conspicuous blocks of heterochromatin were found interstitially on the chromosomes of Gymnotus inaequilabiatus, Gymnotus cf. carapo,and Gymnotus pantherinus. All four species showed single nucleolus organizing regions confirmed by results obtained through Ag-NORs and FISH experiments using 18S rDNA probes, which showed the NORs localized on the first chromosome pair in Gymnotus inaequilabiatus, Gymnotus cf. carapo,and Gymnotus pantherinus, and on pair 2 in Gymnotus sylvius. CMA3 staining revealed additional unrelated NORs marks in Gymnotus sylvius and Gymnotus pantherinus. The 5S rDNA probes revealed signals on one pair in Gymnotus sylvius and two pairs in Gymnotus pantherinus; Gymnotus inaequilabiatus had about seventeen pairs marked, and Gymnotus cf. carapo had about fifteen pairs marked. It is considered that the high amount of heterochromatin identified in the chromosomes of Gymnotus inaequilabiatus and Gymnotus cf. carapo could have facilitated the dispersion of 5S rDNA in these species. Interstitial signals were detected on the first metacentric pair of Gymnotus sylvius by telomeric probes (TTAGGG)n indicating the possible occurrence of chromosomal fusions in this species. The present study reveals valuable cytotaxonomic markers for this group and allows a more precise evaluation of the processes involved in the karyotype differentiation and the interrelationships among different species of the genus Gymnotus. PMID:24260631

  8. Infrapopulations of Gyliauchen volubilis Nagaty, 1956 (Trematoda: Gyliauchenidae) in the rabbitfish Siganus rivulatus (Teleostei: Siganidae) from the Saudi coast of the Red Sea.

    PubMed

    Al-Jahdali, M O

    2012-08-01

    In hermaphroditic helminth parasites, infrapopulation size or mating group size mostly affects some processes acting within the infrapopulation. Here, 30 natural infrapopulations (12-154 individuals) of the intestinal trematode Gyliauchen volubilis Nagaty, 1956 from the fish Siganus rivulatus consisting of newly excysted juveniles, immature and mature worms were found distributed in a well-defined fundamental niche (anterior 40% of the intestine). In small infrapopulations, all stages of the parasite were alive. In larger infrapopulations, differential mortality was only and consistently observed among newly excysted juveniles, and gradually increased to include most or all juveniles in the largest infrapopulations. Among mature worms, the mean worm length seemed unaffected by the infrapopulation size. However, the ratio mean testis size-mean ovary size, a reliable indicator of resource allocation to the male function and of opportunities for cross fertilization, significantly increased with mating group size. In small infrapopulations, all stages of the parasite were scattered along the niche, and never seen in mating pairs (possibly reproduced by self-fertilization). In larger infrapopulations, newly excysted juveniles and immature worms were scattered along the anterior two thirds of the niche, while mature worms were constantly found aggregated in its posterior third (narrow microhabitat), where some were arranged in mating pairs. The probability of mating reciprocally or unilaterally was dependent on body size. The mean number of uterine eggs per worm significantly decreased and their mean sizes significantly increased with mating group size. The results are statistically significant and suggest that infrapopulation self-regulation is greatly associated with its size.

  9. Devario fangae and Devario myitkyinae, two new species of danionin cyprinids from northern Myanmar (Teleostei: Cyprinidae: Danioninae).

    PubMed

    Kullander, Sven O

    2017-02-03

    Devario comprises 38 potentially valid species in southern Asia. Ten species of Devario have been reported so far from Myanmar, six of which belong in the group of striped devarios, with predominantly horizontal stripes in the colour pattern. Among them, records of D. aequipinnatus most likely represent misidentifications. Remaining species of striped devarios in Myanmar are known only from brief descriptions and are in need of taxonomic revision. Devario yuensis and D. deruptotalea, known previously only from India, are here reported for the first time from Myanmar. Devario fangae, new species, is described on the basis of specimens collected in 1998 from small streams in Putao in the extreme north of Myanmar. These streams drain to the Mali Hka River, a tributary of the Ayeyarwaddy River. Devario fangae shares uniquely with D. browni and D. kakhienensis an anterior expansion in width of the middle dark stripe on the side (P stripe). It differs from D. browni and D. kakhienensis in presence of a broad P stripe, wider than adjacent interstripes, vs. narrow, as wide as or narrower than interstripes. Devario fangae is further similar to other species of Devario characterized by three dark stripes (P, P+1, P-1) along the side, but differs from these in having all three stripes wide and of about equal width vs. P stripe wide and P+1 and P-1 stripes much narrower. The largest specimen of D. fangae is 61.0 mm SL. Females are significantly more deep-bodied than males. A specimen of D. aequipinnatus reported from Putao in 1919 probably represents D. fangae.        Devario myitkyinae, new species, is described on the basis of specimens collected in 1997 and 1998 from a stream and lake in the Ayeyarwaddy River drainage near Myitkyina in northern Myanmar. It is similar to D. browni and D. kakhienensis, but different from D. fangae in having horizontal stripes on side equal in width, narrow, irregular, and to some extent curved away from horizontal extension. Devario myitkyinae differs from D. browni, D. kakhienensis, and D. fangae in absence of anterior widening of the P stripe. Devario myitkyinae is similar to other species of Devario characterized by three dark stripes (P, P+1, P-1) along the side, but differs from these in having all three stripes irregular and of equal width vs. stripes regular, P stripe wide and P+1 and P-1 stripes much narrower. The largest wild specimen of D. myitkyinae is 68.7 mm SL. A specimen collected near Myitkyina and reported as D. aequipinnatus in 1929 probably represents D. myitkyinae.

  10. Parallel body shape divergence in the Neotropical fish genus Rhoadsia (Teleostei: Characidae) along elevational gradients of the western slopes of the Ecuadorian Andes

    PubMed Central

    Malato, Grace; Shervette, Virginia R.; Navarrete Amaya, Ronald; Valdiviezo Rivera, Jonathan; Nugra Salazar, Fredy; Calle Delgado, Paola; Karpan, Kirby C.

    2017-01-01

    Neotropical mountain streams are important contributors of biological diversity. Two species of the characid genus Rhoadsia differing for an ecologically important morphological trait, body depth, have been described from mountain streams of the western slopes of the Andes in Ecuador. Rhoadsia altipinna is a deeper-bodied species reported from low elevations in southwestern Ecuador and northern Peru, and Rhoadsia minor is a more streamlined species that was described from high elevations (>1200 m) in the Esmeraldas drainage in northwestern Ecuador. Little is known about these species and their validity as distinct species has been questioned. In this study, we examine how their body shape varies along replicated elevational gradients in different drainages of western Ecuador using geometric morphometrics and the fineness ratio. We also use sequences of the mitochondrial cytochrome oxidase c I gene and the second intron of the S7 nuclear gene to examine whether genetic data are consistent with the existence of two species. We found that body depth varies continuously among populations within drainages as a function of elevation, and that body shape overlaps among drainages, such that low elevation populations of R. minor in the Esmeraldas drainage have similar body depths to higher elevation R. altipinna in southern drainages. Although a common general trend of declining body depth with elevation is clear, the pattern and magnitude of body shape divergence differed among drainages. Sequencing of mitochondrial and nuclear genes failed to meet strict criteria for the recognition of two species (e.g., reciprocal monophyly and deep genetic structure). However, there was a large component of genetic variation for the COI gene that segregated among drainages, indicating significant genetic divergence associated with geographic isolation. Continued research on Rhoadsia in western Ecuador may yield significant insight into adaptation and speciation in Neotropical mountain streams. PMID:28658255

  11. Next generation sequencing yields the complete mitochondrial genome of the Endangered Chilean silverside Basilichthys microlepidotus (Jenyns, 1841) (Teleostei, Atherinopsidae), validated with RNA-seq.

    PubMed

    Véliz, David; Vega-Retter, Caren; Quezada-Romegialli, Claudio

    2016-01-01

    The complete sequence of the mitochondrial genome for the Chilean silverside Basilichthys microlepidotus is reported for the first time. The entire mitochondrial genome was 16,544 bp in length (GenBank accession no. KM245937); gene composition and arrangement was conformed to that reported for most fishes and contained the typical structure of 2 rRNAs, 13 protein-coding genes, 22 tRNAs and a non-coding region. The assembled mitogenome was validated against sequences of COI and Control Region previously sequenced in our lab, functional genes from RNA-Seq data for the same species and the mitogenome of two other atherinopsid species available in Genbank.

  12. Confirmation of the immunoreactivity of monoclonal anti-human C-terminal EGFR antibodies in bronze Corydoras Corydoras aeneus (Callichthyidae Teleostei) by Western Blot method.

    PubMed

    Mytych, Jennifer; Satora, Leszek; Kozioł, Katarzyna

    2018-02-01

    Bronze corydoras (Corydoras aeneus) uses the distal part of the intestine as accessory respiratory organ. Our previous study showed the presence of epidermal growth factor receptor (EGFR) cytoplasmic domain in the digestive tract of the bronze corydoras. In this study, using Western Blot method, we validated the results presented in the previous research. In detail, results of Western Blot analysis on digestive and respiratory part of bronze corydoras intestine homogenates confirmed the immunoreactivity of anti-cytoplasmic domain (C-terminal) human EGFR antibodies with protein band of approximately 180kDa (EGFR molecular weight). This indicates a high homology of EGFR domain between these species and the possibility of such antibody use in bronze corydoras. Statistically significantly higher EGFR expression was observed in the respiratory part of intestine when compared to the digestive part. This implies higher proliferation activity and angiogenesis of epithelium in this part of intestine, creating conditions for air respiration. Therefore, Corydoras aeneus may be considered as a model organism for the molecular studies of the mechanisms of epithelial proliferation initiation and inhibition depending on hypoxia and normoxia. Copyright © 2017. Published by Elsevier GmbH.

  13. Evaluation of the antioxidant system and neurotoxic effects observed in Rhamdia branneri (Teleostei: Heptapteridae) sampled from streams of the lower Iguazu River basin.

    PubMed

    Sobjak, Thaís Maylin; Romão, Silvia; Cazarolli, Luisa Helena; Sampaio, Silvio César; Remor, Marcelo Bevilacqua; Guimarães, Ana Tereza Bittencourt

    2018-07-15

    The use of multiple biomarkers has been shown to be an efficient method for evaluating environmental contamination. In this work, we evaluate neurotoxic effects and the antioxidant system responses of the R. branneri collected in two streams of lower Iguazu River basin, relating them with different percentage of vegetation coverture, presence of pesticides and fall and winter seasons. The biological samples were collected in March and August of 2015, from two streams that belong to the lower Iguazu River basin (Brazil): the Manoel Gomes River and the Arquimedes Stream. Soil analyses were performed, and the results showed the presence of the following organophosphates in the Manoel Gomes River and the Arquimedes Stream: disulfoton, methyl parathion, and ronnel. The present study detected inhibition of cholinesterase activity in the brain and muscle of fish samples during the fall from the Manoel Gomes River and the Arquimedes Stream. In the Manoel Gomes River, elevated lipoperoxidation was also observed during the fall. It was observed that the increase or decrease of biomarkers was related to temporal variation and, possibly, to the exposure of animals to agrochemicals. Although the Manoel Gomes River and the Arquimedes Stream are located in regions with large areas of vegetation, the soil analyses show that agrochemical residues are able to reach these locations, which suggests that the fauna are in contact with oxidant and anti-cholinesterase agents during the fall, in addition to respond differently during each season. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Testing the enemy release hypothesis: abundance and distribution patterns of helminth communities in grey mullets (Teleostei: Mugilidae) reveal the success of invasive species.

    PubMed

    Sarabeev, Volodimir; Balbuena, Juan Antonio; Morand, Serge

    2017-09-01

    The abundance and aggregation patterns of helminth communities of two grey mullet hosts, Liza haematocheilus and Mugil cephalus, were studied across 14 localities in Atlantic and Pacific marine areas. The analysis matched parasite communities of (i) L. haematocheilus across its native and introduced populations (Sea of Japan and Sea of Azov, respectively) and (ii) the introduced population of L. haematocheilus with native populations of M. cephalus (Mediterranean, Azov-Black and Japan Seas). The total mean abundance (TMA), as a feature of the infection level in helminth communities, and slope b of the Taylor's power law, as a measure of parasite aggregation at the infra and component-community levels, were estimated and compared between host species and localities using ANOVA. The TMA of the whole helminth community in the introduced population of L. haematocheilus was over 15 times lower than that of the native population, but the difference was less pronounced for carried (monogeneans) than for acquired (adult and larval digeneans) parasite communities. Similar to the abundance pattern, the species distribution in communities from the invasive population of L. haematocheilus was less aggregated than from its native population for endoparasitic helminths, including adult and larval digeneans, while monogeneans showed a similar pattern of distribution in the compared populations of L. haematocheilus. The aggregation level of the whole helminth community, endoparasitic helminths, adult and larval digeneans was lower in the invasive host species in comparison with native ones as shown by differences in the slope b. An important theoretical implication from this study is that the pattern of parasite aggregation may explain the success of invasive species in ecosystems. Because the effects of parasites on host mortality are likely dose-dependent, the proportion of susceptible host individuals in invasive species is expected to be lower, as the helminth distribution in the invasive host was featured by a higher number of uninfected hosts and a shorter distribution tail when compared with native species. Copyright © 2017 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

  15. Gobiesox lanceolatus, a new species of clingfish (Teleostei:  Gobiesocidae) from Los Frailes submarine canyon, Gulf of California, Mexico.

    PubMed

    Hastings, Philip A; Conway, Kevin W

    2017-01-17

    Gobiesox lanceolatus is described from a single specimen collected from 300 meters depth in the Los Frailes submarine canyon in the southwestern Gulf of California. The "Canyon Clingfish" is unique within Gobiesox in having a lanceolate caudal fin, with the central rays longer than those above and below them. It is also distinguished by 14 dorsal-fin rays (first tiny and unsegmented), 11 anal-fin rays, 28 pectoral-fin rays, anus slightly closer to anal-fin origin than to posterior margin of pelvic disc, and dorsal-fin origin in front of vertical from anus. It is most similar to Gobiesox eugrammus, known from Isla Guadelupe, the coast of outer Baja California and southern California. This is the deepest record for a species of Gobiesox and only four other species of clingfishes are known from greater depths.

  16. Local ecological knowledge of the artisanal fishers on Epinephelus itajara (Lichtenstein, 1822) (Teleostei: Epinephelidae) on Ilhéus coast – Bahia State, Brazil

    PubMed Central

    2014-01-01

    Background Local Ecological Knowledge (LEK) of traditional fishermen may be the only source of information regarding the conservation of the marine ecosystem and its endangered species. One of these species is Epinephelus itajara, which can exceed 2 m in length and 400 kg weight, is classified by the IUCN as a critically endangered. In Brazil, there is currently a moratorium that prohibits the capture of this specie, and in the northeastern coast, a Marine Protected Area was recently established properly justified by the existence a one spawning aggregation. The scope of the present study was the analysis the LEK of fishers with the goal of contributing to the conservation of E. Itajara. Methods The Knowledge of 24 “experts” was recorded through semi-structured interviews with fishermen selected based on their expertise. LEK regarding some aspects of the life history of E. itajara, such as its morphology, spatial distribution, feeding, breeding and conservation, was systematized. The interviews were conducted in synchronic and diachronic situations. The data analysis followed the model of unity of the various individual skills, while the consistency of the analysis was tested using a matrix of methods employed in comparative cognitive science. Potential reproductive aggregation sites were identified by experts through projective interviews conducted based on a cartographic database and transferred to a geographic information system (GIS). Results The LEK of these specialists in relation to the biological and ecological characteristics of E. itajara showed a high level of detail and a high agreement with the scientific literature. Projective interviews are presented as a promising tool allowing spatialization of the information generated through the registration of LEK. Therefore, the visualization of information from the fishermen, as well as its analysis and comparison with other databases, is simplified, thereby contributing to the decision-making process concerning the conservation of marine ecosystem in Brazil. Conclusions Integration of LEK with scientific knowledge is an efficient strategy for the conservation of endangered species, as it provides important additional biological information that can be used in the process of participative and sustainable management of marine resources. PMID:24965849

  17. Redescription of Neoechinorhynchus (Neoechinorhynchus) golvani Salgado-Maldonado, 1978 (Acanthocephala: Neoechinorhynchidae) and description of a new species from freshwater cichlids (Teleostei: Cichlidae) in Mexico.

    PubMed

    Salgado-Maldonado, Guillermo

    2013-05-01

    A redescription of Neoechinorhynchus (Neoechinorhynchus) golvani Salgado-Maldonado (An Inst Biol Univ Nal Autón Méx, Ser Zool 49:35-47, 1978) is presented, based on adult specimens collected from the type host Paraneetroplus fenestratus from the type location, the Lago de Catemaco lake, Veracruz state, Mexico, and its presence is recorded in other cichlids. Detailed studies of N. (N.) golvani using light microscopy revealed some taxonomically important, previously unreported features, such as the size and shape of fully developed adult males and females, and the structure of the eggs. Morphological variability in N. (N.) golvani is described. Based on these data, the geographic distribution of this species is documented. Neoechinorhynchus (Neoechinorhynchus) panucensis n. sp. is described from Herichthys labridens (Pellegrin), Amatitlania nigrofasciata (Günther), and Herichthys cyanoguttatus Baird and Girard (all of them Cichlidae), collected in the Río Atlapexco, a tributary to the upper Río Panuco basin, Hidalgo State, Mexico. This new species stand up alone because of its minute proboscis (♂ 50 × 60, ♀ 42-55 (48.5) × 48-63 (57.7)) and anterior hooks (♂ 27-30 (28.8) × 3-5 (4), ♀ 28-32 (30) × 5 (5)). A key to the species of Neoechinorhynchus recorded from freshwater fishes in Central and South America is included.

  18. Use of dynamic occupancy models to assess the response of Darters (Teleostei: Percidae) to varying hydrothermal conditions in a southeastern United States tailwater

    USGS Publications Warehouse

    Shea, C.P.; Bettoli, Phillip William; Potoka, K. M.; Saylor, C. F.; Shute, P. W.

    2015-01-01

    During the past 100 years, most large rivers in North America have been altered for flood control, hydropower, navigation or water supply development. Although these activities clearly provide important human services, their associated environmental disturbances can profoundly affect stream-dwelling organisms. We used dynamic multi-species occupancy models combined with a trait-based approach to estimate the influence of site-level and species-level characteristics on patch dynamic rates for 15 darter species native to the Elk River, a large, flow-regulated Tennessee River tributary in Tennessee and Alabama. Dynamic occupancy modelling results indicated that for every 2.5 °C increase in stream temperature, darters were 3.94 times more likely to colonize previously unoccupied stream reaches. Additionally, large-bodied darter species were 3.72 times more likely to colonize stream reaches compared with small-bodied species, but crevice-spawning darter species were 5.24 times less likely to colonize previously unoccupied stream reaches. In contrast, darters were 2.21 times less likely to become locally extinct for every 2.5 °C increase in stream temperature, but high stream discharge conditions elevated the risk of local extinction. Lastly, the presence of populations in neighbouring upstream study reaches contributed to a lower risk of extinction, whereas the presence of populations in neighbouring downstream study reaches contributed to higher rates of colonization. Our study demonstrates the application of a trait-based approach combined with a metapopulation framework to assess the patch dynamics of darters in a regulated river. Results from our study will provide a baseline for evaluating the ecological consequences of alternative dam operations.

  19. Genetic characterization of Plectorhinchus mediterraneus yields important clues about genome organization and evolution of multigene families

    PubMed Central

    2012-01-01

    Background Molecular and cytogenetic markers are of great use for to fish characterization, identification, phylogenetics and evolution. Multigene families have proven to be good markers for a better understanding of the variability, organization and evolution of fish species. Three different tandemly-repeated gene families (45S rDNA, 5S rDNA and U2 snDNA) have been studied in Plectorhinchus mediterraneus (Teleostei: Haemulidae), at both molecular and cytogenetic level, to elucidate the taxonomy and evolution of these multigene families, as well as for comparative purposes with other species of the family. Results Four different types of 5S rDNA were obtained; two of them showed a high homology with that of Raja asterias, and the putative implication of a horizontal transfer event and its consequences for the organization and evolution of the 5S rDNA have been discussed. The other two types do not resemble any other species, but in one of them a putative tRNA-derived SINE was observed for the first time, which could have implications in the evolution of the 5S rDNA. The ITS-1 sequence was more related to a species of another different genus than to that of the same genus, therefore a revision of the Hamulidae family systematic has been proposed. In the analysis of the U2 snDNA, we were able to corroborate that U2 snDNA and U5 snDNA were linked in the same tandem array, and this has interest for tracing evolutionary lines. The karyotype of the species was composed of 2n = 48 acrocentric chromosomes, and each of the three multigene families were located in different chromosome pairs, thus providing three different chromosomal markers. Conclusions Novel data can be extracted from the results: a putative event of horizontal transfer, a possible tRNA-derived SINE linked to one of the four 5S rDNA types characterized, and a linkage between U2 and U5 snDNA. In addition, a revision of the taxonomy of the Haemulidae family has been suggested, and three cytogenetic

  20. Ultrastructural and molecular characterization of Glugea serranus n. sp., a microsporidian infecting the blacktail comber, Serranus atricauda (Teleostei: Serranidae), in the Madeira Archipelago (Portugal).

    PubMed

    Casal, Graça; Rocha, Sónia; Costa, Graça; Al-Quraishy, Saleh; Azevedo, Carlos

    2016-10-01

    A new microsporidian infecting the connective tissue of the coelomic cavity of the blacktail comber Serranus atricauda, in the Madeira Archipelago (Portugal), is described on the basis of morphological, ultrastructural, and molecular features. The microsporidian formed large whitish xenomas adhering to the peritoneal visceral organs of the host. Each xenoma consisted of a single hypertrophic cell, in the cytoplasm of which mature spores proliferated within parasitophorous vacuoles surrounded by numerous collagen fibers. Mature spores were ellipsoidal and uninucleated, measuring an average of 6.5 ± 0.5 μm in length and 3.4 ± 0.6 μm in width. The anchoring disk of the polar filament was subterminal, laterally shifted from the anterior pole of the spore. The isofilar polar filament coiled in 18-19 turns, forming two rows that surrounded the posterior vacuole. The latter occupied about one third of the spore length. The polaroplast surrounding the apical and uncoiled portion of the polar filament displayed two distinct regions: a lamellar region and an electron-dense globule. Molecular analysis of the rRNA genes, including the internal transcribed spacer region, and phylogenetic analysis using maximum likelihood and neighbor joining demonstrated that this microsporidian parasite clustered with some Glugea species. Based on the differences found both at the morphological and molecular levels, to other members of the genus Glugea, the microsporidian infecting the blacktail comber is considered a new species, thus named Glugea serranus n. sp.

  1. Biodiversity of the Betta smaragdina (Teleostei: Perciformes) in the northeast region of Thailand as determined by mitochondrial COI and nuclear ITS1 gene sequences☆

    PubMed Central

    Kowasupat, Chanon; Panijpan, Bhinyo; Laosinchai, Parames; Ruenwongsa, Pintip; Phongdara, Amornrat; Wanna, Warapond; Senapin, Saengchan; Phiwsaiya, Kornsunee

    2014-01-01

    In Thailand, there are currently five recognized species members of the bubble-nesting Betta genus, namely Betta splendens, B. smaragdina, B. imbellis, B. mahachaiensis and B. siamorientalis. In 2010, we indicated the possibility, based on COI barcoding evidence, that there might be two additional species, albeit cryptic, related to the type-locality B. smaragdina in some provinces in the northeast of Thailand. In the present study, after a more extensive survey of the northeast, and phylogenetic analyses based on COI and ITS1 sequences, the B. smaragdina group may be composed of at least 3 cryptic species members. The phylogenetic positions of these B. smaragdina group members in the bubble-nesting bettas' tree together with those of their congeners have been consolidated by better DNA sequence quality and phylogenetic analyses. With a better supported tree, the species statuses of B. siamorientalis and the Cambodian B. smaragdina-like fish, B. stiktos, are also confirmed. PMID:25606392

  2. Stereological estimation of the surface area and oxygen diffusing capacity of the respiratory stomach of the air-breathing armored catfish Pterygoplichthys anisitsi (Teleostei: Loricariidae).

    PubMed

    da Cruz, André Luis; Pedretti, Ana Carolina Elias; Fernandes, Marisa Narciso

    2009-05-01

    The stomach of Pterygoplichthys anisitsi has a thin, translucent wall and a simple squamous epithelium with an underlying dense capillary network. In the cardiac and pyloric regions, most cells have short microvilli distributed throughout the cell surface and their edges are characterized by short, densely packed microvilli. The mucosal layer of the stomach has two types of pavement epithelial cells that are similar to those in the aerial respiratory organs. Type 1 pavement epithelial cells, resembling the Type I pneumocyte in mammal lungs, are flat, with a large nucleus, and extend a thin sheet of cytoplasm on the underlying capillary. Type 2 cells, resembling the Type II pneumocyte, possess numerous mitochondria, a well-developed Golgi complex, rough endoplasmic reticulum, and numerous lamellar bodies in different stages of maturation. The gastric glands, distributed throughout the mucosal layer, also have several cells with many lamellar bodies. The total volume (air + tissue), tissue, and air capacity of the stomach when inflated, increase along with body mass. The surface-to-tissue-volume ratio of stomach varies from 108 cm(-1) in the smallest fish (0.084 kg) to 59 cm(-1) in the largest fish (0.60 kg). The total stomach surface area shows a low correlation to body mass. Nevertheless, the body-mass-specific surface area varied from 281.40 cm(2) kg(-1) in the smallest fish to 68.08 cm(2) kg(-1) in the largest fish, indicating a negative correlation to body mass (b = -0.76). The arithmetic mean barrier thickness between air and blood was 1.52 +/- 0.07 microm, whereas the harmonic mean thickness (tau(h)) of the diffusion barrier ranged from 0.40 to 0.74 microm. The anatomical diffusion factor (ADF = cm(2) microm(-1) kg(-1)) and the morphological O(2) diffusion capacity (D(morphol)O(2) = cm(3) min(-1) mmHg(-1) kg(-1)) are higher in the smallest specimen and lower in the largest one. In conclusion, the structure and morphometric data of P. anisitsi stomach indicate that this organ is adapted for oxygen uptake from air. (c) 2008 Wiley-Liss, Inc.

  3. A new species of freshwater eel-tailed catfish of the genus Tandanus (Teleostei: Plotosidae) from coastal rivers of mid-northern New South Wales, Australia

    USGS Publications Warehouse

    Welsh, Stuart A.; Jerry, Dean R.; Burrows, Damien; Rourke, Meaghan L.

    2017-01-01

    Tandanus bellingerensis, new species, is described based on specimens from four river drainages (Bellinger, Macleay, Hastings, and Manning rivers) of the mid-northern coast of New South Wales, Australia. Previously, three species were recognized in the genus Tandanus: T. tropicanus of the wet tropics region of northeast Queensland, T. tandanus of the Murray-Darling drainage and coastal streams of central-southern Queensland and New South Wales, and T. bostocki of southwestern Western Australia. The new species is distinguished from all congeners by a combination of the following morphologic characters: a high count of rays in the continuous caudodorsal and anal fins (range 153–169, mode 159), a high count of gill rakers on the first arch (range 35–39, mode 36), and strongly recurved posterior serrae of the pectoral-fin spine. Additionally, results from previously conducted genetic studies corroborate morphologic and taxonomic distinctness of the new species.

  4. Skeletal ontogeny of the vertebral column and of the fins in shi drum Umbrina cirrosa (Teleostei: Perciformes: Sciaenidae), a new candidate species for aquaculture.

    PubMed

    Neofytou, M; Sfakianakis, D G; Koumoundouros, G; Mylonas, C C; Kentouri, M

    2017-09-01

    The osteological development of the vertebral column and fins in shi drum Umbrina cirrosa was studied in order to improve knowledge for its introduction in Mediterranean aquaculture. The osteological development was studied in 171 individuals, of total length (L T ) from 2·7 to 30·2 mm that were reared under the mesocosm technique. Vertebral ontogeny starts at 3·4 and 4·0 mm L T , with the formation of the first cartilaginous neural and haemal arches, and spines, respectively, and is completed with the full attainment of epicentrals (12·5 mm L T ). The formation of vertebral centra occurs between 4·1 and 7·4 mm L T . Pectoral supports are the first fin elements to develop (3·0 mm L T ), followed by those of the caudal fin (3·8 mm L T ), pelvic fin (3·9 mm L T ) and finally by those of the dorsal and anal fins (4·5 mm L T ). The caudal fin is the first to develop fin rays and attain the full count of principal fin rays (4·5-6·8 mm L T ), but the last to be fully completed with the formation of procurrent fin rays (6·9-17·5 mm L T ). The next fins starting to present rays are the dorsal (5·3 mm L T ) and the pectoral fins (5·6 mm L T ), while the anal and pelvic fins are the last (5·7 mm L T ). Following the caudal principal fin rays (6·8 mm L T ), the dorsal, anal (6·9 mm L T ), pelvic (7·4 mm L T ) and pectoral fins (9·8 mm L T ) are the next with fully completed ray counts. Aggregation of qualitative changes, such as the appearance of cartilages, the beginning and the complement of the ossification process and the full complement of elements in U. cirrosa were measured as cumulative frequency counts. These measurements reveal three ontogenetic intervals: one very developmentally active period during early life stages (from 3 to 5·9 mm L T ), a second slower developmental period (from 6·0 to 8·9 mm L T ) and finally a period of ontogeny more focused on structure refinement up to metamorphosis and settlement (>9·0 mm L T ). © 2017 The Fisheries Society of the British Isles.

  5. Seven new species within western Atlantic Starksia atlantica, S. lepicoelia, and S. sluiteri (Teleostei, Labrisomidae), with comments on congruence of DNA barcodes and species

    PubMed Central

    Baldwin, Carole C.; Castillo, Cristina I.; Weigt, Lee A.; Benjamin C., Victor

    2011-01-01

    Abstract Specimens of Starksia were collected throughout the western Atlantic, and a 650-bp portion of the mitochondrial gene cytochrome oxidase-c subunit I (COl) was sequenced as part of a re-analysis of species diversity of western Central Atlantic shorefishes. A neighbor-joining tree constructed from the sequence data suggests the existence of several cryptic species. Voucher specimens from each genetically distinct lineage and color photographs of vouchers taken prior to dissection and preservation were examined for diagnostic morphological characters. The results suggest that Starksia atlantica, Starksia lepicoelia, and Starksia sluiteri are species complexes, and each comprises three or more species. Seven new species are described. DNA data usually support morphological features, but some incongruence between genetic and morphological data exists. Genetic lineages are only recognized as species if supported by morphology. Genetic lineages within western Atlantic Starksia generally correspond to geography, such that members of each species complex have a very restricted geographical distribution. Increasing geographical coverage of sampling locations will almost certainly increase the number of Starksia species and species complexes recognized in the western Atlantic. Combining molecular and morphological investigations is bringing clarity to the taxonomy of many genera of morphologically similar fishes and increasing the number of currently recognized species. Future phylogenetic studies should help resolve species relationships and shed light on patterns of speciation in western Atlantic Starksia. PMID:21594143

  6. Description of Danio absconditus, new species, and redescription of Danio feegradei (Teleostei: Cyprinidae), from the Rakhine Yoma hotspot in south-western Myanmar.

    PubMed

    Kullander, Sven O; Britz, Ralf

    2015-04-21

    Danio feegradei Hora is redescribed based on recently collected specimens from small coastal streams on the western slope of the Rakhine Yoma, ranging from the Thade River drainage southward to slightly north of Kyeintali. Danio absconditus, new species, is described from the Kyeintali Chaung and small coastal streams near Gwa, south of the range of D. feegradei. Both species are distinguished from other Danio by the presence of a dark, elongate or round spot at the base of the caudal fin and a cleithral marking composed of a small black spot margined by a much smaller orange spot. Danio feegradei is characterized by the colour pattern, with series of white spots along the otherwise dark side; D. absconditus by about 7--11 dark vertical bars on the abdominal side. Within Danio, the presence of a complete lateral line, cleithral spot, and 14 circumpeduncular scales is shared with D. dangila and similar species, but these character states may be plesiomorphic as suggested by the shared presence of cleithral spot and complete lateral line in Devario and Betadevario. In other Danio the cleithral spot is absent, the lateral line is short or absent, and the circumpeduncular scale count is lower (10-12). Twenty teleost species are reported from streams on the western slope of the Rakhine Yoma, all probably endemic. The parapatric distribution of D. absconditus and D. feegradei is unique within the genus, and may be partly explained by changes in eustatic sea levels.

  7. The identity of Aplocheilus andamanicus (Köhler, 1906) (Teleostei: Cyprinodontiformes), an endemic Killifish from the Andaman Islands, with notes on Odontopsis armata van Hasselt.

    PubMed

    Katwate, Unmesh; Kumkar, Pradeep; Britz, Ralf; Raghavan, Rajeev; Dahanukar, Neelesh

    2018-02-20

    In his work on the fishes of the Andaman Islands, Francis Day (1870) collected large-sized specimens of Aplocheilus from the south Andamans. Despite differences in the size and dorsal-fin ray counts, Day refrained from recognising the Andaman Aplocheilus as a distinct species and considered it as Aplocheilus panchax, a species distributed in the Ganges delta and across the eastern coast of mainland India. However, Day mentioned the differences in fin-ray counts between these two populations. Subsequently Köhler (1906) described the Andaman population as Haplochilus andamanicus (now in Aplocheilus), referring to the diagnostic characters initially discovered by Day. This species failed to receive recognition from taxonomists, because of the uncertainty regarding the validity of the species and its questionable synonymy with A. panchax. In this study, based on morphological and molecular evidence, we demonstrate that A. andamanicus is indeed a distinct and valid species, which can easily be diagnosed from the widespread A. panchax. While resolving the identity of A. andamanicus, we also demonstrate that the congeners from southeast Asia form a genetically distinct group for which the name Odontopsis armata is available.

  8. Genetic, comparative genomic, and expression analyses of the Mc1r locus in the polychromatic Midas cichlid fish (Teleostei, Cichlidae Amphilophus sp.) species group.

    PubMed

    Henning, Frederico; Renz, Adina Josepha; Fukamachi, Shoji; Meyer, Axel

    2010-05-01

    Natural populations of the Midas cichlid species in several different crater lakes in Nicaragua exhibit a conspicuous color polymorphism. Most individuals are dark and the remaining have a gold coloration. The color morphs mate assortatively and sympatric population differentiation has been shown based on neutral molecular data. We investigated the color polymorphism using segregation analysis and a candidate gene approach. The segregation patterns observed in a mapping cross between a gold and a dark individual were consistent with a single dominant gene as a cause of the gold phenotype. This suggests that a simple genetic architecture underlies some of the speciation events in the Midas cichlids. We compared the expression levels of several candidate color genes Mc1r, Ednrb1, Slc45a2, and Tfap1a between the color morphs. Mc1r was found to be up regulated in the gold morph. Given its widespread association in color evolution and role on melanin synthesis, the Mc1r locus was further investigated using sequences derived from a genomic library. Comparative analysis revealed conserved synteny in relation to the majority of teleosts and highlighted several previously unidentified conserved non-coding elements (CNEs) in the upstream and downstream regions in the vicinity of Mc1r. The identification of the CNEs regions allowed the comparison of sequences from gold and dark specimens of natural populations. No polymorphisms were found between in the population sample and Mc1r showed no linkage to the gold phenotype in the mapping cross, demonstrating that it is not causally related to the color polymorphism in the Midas cichlid.

  9. Differential expression of myogenic regulatory factor MyoD in pacu skeletal muscle (Piaractus mesopotamicus Holmberg 1887: Serrasalminae, Characidae, Teleostei) during juvenile and adult growth phases.

    PubMed

    de Almeida, Fernanda Losi Alves; Carvalho, Robson Francisco; Pinhal, Danillo; Padovani, Carlos Roberto; Martins, Cesar; Dal Pai-Silva, Maeli

    2008-12-01

    Skeletal muscle is the edible part of the fish. It grows by hypertrophy and hyperplasia, events regulated by differential expression of myogenic regulatory factors (MRFs). The study of muscle growth mechanisms in fish is very important in fish farming development. Pacu (Piaractus mesopotamicus) is one of the most important food species farmed in Brazil and has been extensively used in Brazilian aquaculture programs. The aim of this study was to analyze hyperplasia and hypertrophy and the MRF MyoD expression pattern in skeletal muscle of pacu (P. mesopotamicus) during juvenile and adult growth stages. Juvenile (n=5) and adult (n=5) fish were anaesthetized, sacrificed, and weight (g) and total length (cm) determined. White dorsal region muscle samples were collected and immersed in liquid nitrogen. Transverse sections (10 microm thick) were stained with Haematoxilin-Eosin (HE) for morphological and morphometric analysis. Smallest fiber diameter from 100 muscle fibers per animal was calculated in each growth phase. These fibers were grouped into three classes (<20, 20-50, and >50 microm) to evaluate hypertrophy and hyperplasia in white skeletal muscle. MyoD gene expression was determined by semi-quantitative RT-PCR. PCR products were cloned and sequenced. Juvenile and adult pacu skeletal muscle had similar morphology. The large number of <20 microm diameter muscle fibers observed in juvenile fish confirms active hyperplasia. In adult fish, most fibers were over 50 microm diameter and denote more intense muscle fiber hypertrophy. The MyoD mRNA level in juveniles was higher than in adults. A consensus partial sequence for MyoD gene (338 base pairs) was obtained. The Pacu MyoD nucleotide sequence displayed high similarity among several vertebrates, including teleosts. The differential MyoD gene expression observed in pacu white muscle is possibly related to differences in growth patterns during the phases analyzed, with hyperplasia predominant in juveniles and hypertrophy in adult fish. These results should provide a foundation for understanding the molecular control of skeletal muscle growth in economically important Brazilian species, with a view to improving production quality.

  10. Cryptic speciation reversal in the Etheostoma zonale (Teleostei: Percidae) species group, with an examination of the effect of recombination and introgression on species tree inference.

    PubMed

    Halas, Dominik; Simons, Andrew M

    2014-01-01

    Mitochondrial and nuclear introgression among closely related taxa can greatly complicate the process of determining their phylogenetic relationships. In the Central Highlands of North America, many fish taxa have undergone introgression; in this study, we demonstrate the existence of an unusual introgression event in the Etheostoma zonale species group. We used one mitochondrial and seven nuclear loci to determine the relationships of the taxa within the E. zonale group, and their degree of differentiation. We found evidence of multiple divergent populations within each species; much of the divergence within species has taken place during the Pleistocene. We also found evidence of a previously unknown cryptic species in the Upper Tennessee River which diverged from the remainder of the group during the Pliocene, and has undergone mitochondrial and nuclear introgression with E. zonale, in an apparent process of speciation reversal. We examined the effects that using varying types of recombination tests to eliminate the signal of recombination from nuclear loci would have on the phylogenetic placement of this introgressed lineage in our species tree analyses. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Ligophorus pilengas n. sp. (Monogenea: Ancyrocephalidae) from the introduced So-iuy mullet, Mugil soiuy (Teleostei: Mugilidae), in the Sea of Azov and the Black Sea.

    PubMed

    Sarabeev, Volodimir Leonidovich; Balbuena, Juan Antonio

    2004-04-01

    The monogenean Ligophorus chabaudi was originally described on the gills of the flathead mullet, Mugil cephalus, and was subsequently reported on the So-iuy mullet, Mugil soiuy. However, the morphology of sclerotized parts and multivariate statistical analyses suggest that the form from the So-iuy mullet represents a new species. This study provides a description of the new species Ligophorus pilengas n. sp. and provides additional morphological data concerning the morphology of the ventral bar that might be useful for the diagnosis of Ligophorus. Ligophorus pilengas n. sp. is the second species of Ligophorus reported on the So-iuy mullet. Zoogeographical records indicate that L. pilengas n. sp. was probably introduced to the Black Sea and the Sea of Azov from the western Pacific Ocean together with its host.

  12. Morphology of the jaw, suspensorial, and opercle musculature of Beloniformes and related species (Teleostei: Acanthopterygii), with a special reference to the m. adductor mandibulae complex.

    PubMed

    Werneburg, Ingmar

    2015-01-01

    The taxon Beloniformes represents a heterogeneous group of teleost fishes that show an extraordinary diversity of jaw morphology. I present new anatomical descriptions of the jaw musculature in six selected beloniforms and four closely related species. A reduction of the external jaw adductor (A1) and a changed morphology of the intramandibular musculature were found in many Beloniformes. This might be correlated with the progressively reduced mobility of the upper and lower jaw bones. The needlefishes and sauries, which are characterised by extremely elongated and stiffened jaws, show several derived characters, which in combination enable the capture of fish at high velocity. The ricefishes are characterised by several derived and many plesiomorphic characters that make broad scale comparisons difficult. Soft tissue characters are highly diverse among hemiramphids and flying fishes reflecting the uncertainty about their phylogenetic position and interrelationship. The morphological findings presented herein may help to interpret future phylogenetic analyses using cranial musculature in Beloniformes.

  13. Three new species of Protogyrodactylus Johnston & Tiegs, 1922 (Monogenoidea: Dactylogyridae) from the gills of the longtail silverbiddy Gerres longirostris (Teleostei: Gerreidae) in the Red Sea.

    PubMed

    Galli, Paolo; Kritsky, Delane C

    2008-03-01

    Twenty-one specimens of the longtailed silverbiddy Gerres longirostris (Gerreidae) were examined for dactylogyrid parasites from the Nabq Managed Resource Protected Area, Ras Mohammed National Park (Red Sea) near Sharm El-Sheikh, South Sinai, Egypt. The diagnosis of Protogyrodactylus Johnston & Tiegs, 1922 was amended, and three new species, P. federicae n. sp., P. zullinii n. sp. and P. alatus n. sp., were recovered and described; the prevalence of each species was 100%. P. federicae most closely resembled P. alienus Bychowsky & Nagibina, 1974, but differed from it by possessing two anteromedial projections on the ventral bar, a claw-like ventral anchor sclerite and spatulate dorsal bars. P. zullini was most similar to P. quadratus Johnston & Tiegs, 1922, from which it differed by having a distal hook on the superficial root of the dorsal anchor, an evenly curved ventral anchor shaft and point, and a flange on the bulbous base of the male copulatory organ. P. alatus was closest to P. youngi Bychowsky & Nagibina, 1974, from which it differed by having delicate anchors and two prominent anteromedial processes on the ventral bar.

  14. Lamprologus markerti, a new lamprologine cichlid (Teleostei: Cichlidae) endemic to the lower Congo River in the Democratic Republic of Congo, west-central Africa.

    PubMed

    Tougas, Stephanie; Stiassny, Melanie L J

    2014-08-15

    A new Lamprologus is described from the lower Congo River (LCR) in the Democratic Republic of Congo. Lamprologus markerti, new species, is readily distinguished from L. tigripictilis and L. werneri, the LCR endemic lamprologines with which it was once taxonomically conflated, in the possession of a reduced number of gill rakers on the first arch (9-11 versus 12-17), a longer head (32.1-34.7% SL versus 29.3-31.9 and 29.1-32.9% SL, respectively), and a longer predorsal length (33.0-35.9% SL versus 29.3-32.7 and 28.5-32.6% SL, respectively). Further, L. markerti lacks a second intestinal loop present in both L. tigripictilis and L. werneri, and has a highly reduced infraorbital series often consisting of a single first infraorbital (lachrymal) element. 

  15. Southern limits of distribution of the intertidal gobies Chaenogobius annularis and C. gulosus support the existence of a biogeographic boundary in southern Japan (Teleostei, Perciformes, Gobiidae)

    PubMed Central

    Murase, Atsunobu; Miki, Ryohei; Motomura, Hiroyuki

    2017-01-01

    Abstract Understanding the distributional patterns of individual animal groups with respect to coastal topology and the local physical environment provides essential foundational frameworks for marine zoogeography. In the northwestern Pacific waters of Japan, the distributional pattern of some cool-temperate species of marine fishes suggests the existence of a biogeographic boundary corresponding to a long sandy shore on the eastern coast of Kyushu, southern Japan. The existence of this hypothetical biogeographic boundary was tested by mapping the southern distributional limit of two species of cool-temperate intertidal gobies, Chaenogobius annularis and C. gulosus, which are endemic to East Asia and common in rock pools within their range in the Japanese Archipelago. Distribution and abundance were assessed by survey of museum collections from south-east Kyushu (i.e., the entire coasts of Kagoshima and Miyazaki prefectures); and a quantitative survey of the abundance of these gobies in rock pools at various sites around the hypothesized boundary on the eastern coast of Kyushu, including the subtropical Tanega-shima Island. The museum collection survey showed different distribution patterns between the two species: C. annularis was distributed along the entire coasts of south-east Kyushu including subtropical islands, whereas C. gulosus was distributed along these coasts, including one site on a subtropical island, except for an area south of the hypothesized boundary on the eastern coast of Kyushu. The density and occurrence rates of C. annularis in rock pools decreased with latitude, it being absent from a subtropical island, and C. gulosus was not detected from sites south of the hypothesized boundary. The qualitative survey showed that the southernmost records of C. annularis and C. gulosus were the adjacent subtropical islands (Yaku-shima and Tanega-shima islands respectively), although the quantitative survey suggested that their normal range of distribution was limited to the southern part of the Kyushu mainland. A combination of qualitative and quantitative survey methods in the present study highlighted that the southernmost record of a certain species may not necessarily indicate the true limit of its distribution. The distribution of C. gulosus supports the existence of the hypothetical biogeographic boundary, and the different distribution patterns of the two species may be caused by differences in their early life histories. PMID:29362541

  16. Predator-prey interactions between Synbranchus marmoratus (Teleostei: Synbranchidae) and Hypsiboas pulchellus tadpoles (Amphibia: Hylidae): importance of lateral line in nocturnal predation and effects of fenitrothion exposure.

    PubMed

    Junges, Celina M; Lajmanovich, Rafael C; Peltzer, Paola M; Attademo, Andres M; Bassó, Agustín

    2010-11-01

    Environmental contaminants can disrupt interactions between aquatic species by altering community structure. We explored predator-prey interactions between marbled swamp juvenile eels (Synbranchus marmoratus; predator) and anuran tadpoles (Hypsiboas pulchellus; prey) in relation to two aspects: the importance of lateral line in the predator and whether the absence of light modifies predation rates; and the effect of a sub-lethal concentration of fenitrothion on both predator and prey. Eels were tested under two sensory conditions (lateral line intact and lateral line blocked by cobalt chloride) in dark conditions. Predation rates were evaluated using different treatments that combined predator and prey exposed or not to insecticide. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities were also measured in muscle samples of eels and tadpoles to explore whether fenitrothion affects predator and prey differentially. Marbled swamp eels were more efficient in feeding on tadpoles during the night than during the day, showing that lateral line makes an important contribution to prey detection and capture. Regarding pesticide effects, short-term (6 h) exposure to an ecologically relevant fenitrothion dose of 2.5 mg L(-1) altered the predator-prey relationship by changing prey behaviour, reducing prey detection and therefore increasing tadpole survival. At this concentration, the outcome of the predator-prey relationship appears biased in favor of the exposed tadpoles, which were released from predation risk, despite their altered behaviour and the higher inhibition percentages of tail BChE (70%) and AChE (51%) than in control individuals. Our study involving these model species and agrochemicals demonstrates that fenitrothion affected the outcome of a predator-prey relationship. Further studies are needed, in these species and other native amphibians, to investigate the nature of the mechanisms responsible for the adverse effects of pesticides on antipredator behaviour and predation efficiency. Copyright © 2010 Elsevier Ltd. All rights reserved.

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

    PubMed

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

    2015-01-10

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

  18. Balitora chipkali, a new species of stone loach (Teleostei: Balitoridae) from the northern Western Ghats of India, with a note on the distribution of B. laticauda.

    PubMed

    Kumkar, Pradeep; Katwate, Unmesh; Raghavan, Rajeev; Dahanukar, Neelesh

    2016-07-14

    Balitora chipkali, a new species of stone loach, is described from the westward-flowing Astoli tributary of the Kali River system in the northern part of the Western Ghats, India. The species differs from its congeners in a combination of characters that includes: a single pair of maxillary barbels; a large eye, of diameter greater than 15% head length (HL); snout length less than 4 times eye diameter; gape of mouth less than 30% HL; upper lip with 9-12 papillae in first series and 3-8 papillae in second series; flattened body, of depth less than 15% standard length; caudal-peduncle length less than three times its depth, 66-68 lateral line scales, 11 caudal vertebrae excluding compound centrum, third infraorbital sensory canal tube straight; and a distinct color pattern with almost round 7 dorsal saddles not reaching lateral irregular crossbar markings. Balitora chipkali forms a monophyletic group with B. laticauda as its sister taxon in a phylogeny based on a concatenated cytochrome b (Cytb) and cytochrome oxidase subunit 1 (COI) gene fragments. Raw genetic distance between B. chipkali and B. laticauda was 1.9-2.2% based on COI and 3.4-4.3% based on Cytb partial gene sequences, which was far more than the intra-species variation in widely separated populations of B. laticauda. Based on molecular and morphological analysis, we also provide new locality records for B. laticauda and delimit its distribution to eastward-flowing tributaries of the Krishna River system in the northern Western Ghats.

  19. Observed temporal hydrate-pingo alteration at pockmark G11, Nyegga, - an important climate-change signal?

    NASA Astrophysics Data System (ADS)

    Hovland, M. T.

    2010-12-01

    Complex pockmark G11 at Nyegga, occurs adjacent to the northern flank of the Storegga Slide, off mid-Norway. It is a 12 m deep and 200 - 250 m wide oval-shaped depression at ~750 m water depth. The crater-like depression contains at least six up to 4 m wide and 2 m high hydrate-pingoes in addition to large, rugged methane-derived carbonate rock ridges. Despite an ambient sub-zero water temperature (~ - 0.7 °C), the pockmark teems with life, ranging from primary producers, e.g., chemosynthetic bacteria to higher trophic animals, including filter-feeders, stalked crinoids, large pycnogonids, and various kinds of teleostei, mainly skate and eel pout. One of the circular, cylinder-shaped hydrate pingoes (‘Ice1’, Hovland and Svensen, 2006), was measured in 2004 to be about 1 m in diameter and 25 cm high. It was re-visited with ROV (remotely operated vehicle) in 2009 and was found to have slightly altered its shape and become slightly smaller. The features of the G11-pockmark, including bacterial mats, sampled gas hydrates, high biodiversity, and hydrate-pingoes documents that active fluid flow (seepage) occurs through the seafloor. Although the currently observed activity at G11 seems to be in a mode of slow, steady-state flux, e.g., ‘micro-seepage’, slightly warmer bottom water expected as a consequence of the global warming trend may induce a ‘galloping melting’ or dramatically increased seepage flux in the near future. During the last few years, there has been a trend of ocean bottom water warming along most of the 1500 km long western Norwegian coastline with up to 0.8°C above normal (www.imr.no). If this same trend also occurs at 750 m water depth at Nyegga, about 170 km west of the coastline, then there is a danger of escalating pingo-alteration at G11. Because of its easy access for research vessels and its well-documented near-surface features, G11/Nyegga represents an ideal location for the early-warning documentation of incipient hydrate

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

    PubMed Central

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

    2016-01-01

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

  1. Involvement of pituitary gonadotropins, gonadal steroids and breeding season in sex change of protogynous dusky grouper, Epinephelus marginatus (Teleostei: Serranidae), induced by a non-steroidal aromatase inhibitor.

    PubMed

    Garcia, Carlos Eduardo de O; Araújo, Bruno C; Mello, Paulo H; Narcizo, Amanda de M; Rodrigues-Filho, Jandyr A; Medrado, Andreone T; Zampieri, Ricardo A; Floeter-Winter, Lucile M; Moreira, Renata Guimarães

    2013-10-01

    Two experiments were performed using the aromatase inhibitor (AI) letrozole (100mg/kg) to promote sex change, from female-to-male, in protogynous dusky grouper. One experiment was performed during the breeding season (spring) and the other at the end of the breeding season (summer). During the spring, AI promoted sex change after 9 weeks and the sperm produced was able to fertilize grouper oocytes. During the summer, the sex change was incomplete; intersex individuals were present and sperm was not released by any of the animals. Sex changed gonads had a lamellar architecture; cysts of spermatocytes and spermatozoa in the lumen of the germinal compartment. In the spring, after 4 weeks, 11ketotestosterone (11KT) levels were higher in the AI than in control fish, and after 9 weeks, coincident with semen release, testosterone levels increased in the AI group, while 11KT returned to the initial levels. Estradiol (E2) levels remained unchanged during the experimental period. Instead of decreasing throughout the period, as in control group, 17 α-OH progesterone levels did not change in the AI-treated fish, resulting in higher values after 9 weeks when compared with control fish. fshβ and lhβ gene expression in the AI animals were lower compared with control fish after 9 weeks. The use of AI was effective to obtain functional males during the breeding season. The increase in androgens, modulated by gonadotropins, triggered the sex change, enabling the development of male germ cells, whereas a decrease in E2 levels was not required to change sex in dusky grouper. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. The translocated Liza haematocheila (Teleostei: Mugilidae) as a new host of four species of Saturnius Manter, 1969 (Digenea: Hemiuridae) within its invasive range in the Black Sea.

    PubMed

    Pankov, Plamen; Gibson, David I; Kostadinova, Aneta

    2009-09-01

    This paper presents the first documented record of four species of Saturnius Manter, 1969 in Liza haematocheila (Temminck & Schlegel) in its invasive Pontic range. S. papernai Overstreet, 1977, S. dimitrovi Blasco-Costa, Pankov, Gibson, Balbuena, Raga, Sarabeev & Kostadinova, 2006, S. minutus Blasco-Costa, Pankov, Gibson, Balbuena, Raga, Sarabeev & Kostadinova, 2006 and Saturnius sp. are described and compared with existing data by means of multivariate morphometric analysis. The morphological and morphometric similarities between the specimens of Saturnius sp. from L. haematocheila and a small form of S. papernai from L. aurata indicate the possible existence of another, cryptic species. Although having acquired at least three species of Saturnius since its establishment in the Black Sea region, there is no evidence that a Pacific congener has been introduced with this fish. This is the first report of S. minutus from the Black Sea.

  3. Taxonomic status of Ligophorus mugilinus (Hargis, 1955) (Monogenea: Ancyrocephalidae), with a description of a new species of Ligophorus from Mugil cephalus (Teleostei: Mugilidae) in the Mediterranean Basin.

    PubMed

    Sarabeev, Volodimir Leonidovich; Balbuena, Juan Antonio; Euzet, Louis

    2005-12-01

    Ligophorus mugilinus was originally described on the flathead mullet Mugil cephalus from the Gulf of Mexico. The species was later recorded in the Mediterranean Sea on the flathead mullet and in the Caribbean Sea on the white mullet Mugil curema. After examination of the type material and additional specimens of Ligophorus from the northwest Atlantic coast, the Caribbean Sea, and the Mediterranean and Black Sea, we observed morphological differences concerning haptoral and male copulatory structures between L. mugilinus from the northwest Atlantic and the forms from the Mediterranean and Black Seas. Accordingly, the latter specimens are described as a new species, Ligophorus mediterraneus n. sp. A redescription of L. mugilinus, including new morphometric data, is also given. The morphometric analysis of the Caribbean specimens suggested that their ascription to L. mugilinus is uncertain, but additional material is needed to clarify their specific identity. The results of this study, together with previous zoogeographical evidence, indicate that flathead mullets from different seas harbor different species complexes of Ligophorus. Given the coastal habits of the host, it is suggested that open oceans could act as geographical barriers favoring speciation within disjointed flathead mullet populations.

  4. Population Structure, Genetic Diversity, Effective Population Size, Demographic History and Regional Connectivity Patterns of the Endangered Dusky Grouper, Epinephelus marginatus (Teleostei: Serranidae), within Malta’s Fisheries Management Zone

    PubMed Central

    Vella, Adriana

    2016-01-01

    The objective of this study is to describe the genetic population structure and demographic history of the endangered marine fish, Epinephelus marginatus, within Malta’s Fisheries Management Zone for the purpose of localised conservation planning. Epinephelus marginatus is a long-lived, sedentary, reef-associated protogynous hermaphrodite with high commercial and recreational value that is at risk of extinction throughout its global distribution. Based on global trends, population substructuring and gaps in local knowledge this has led to an increased interest in evaluation of local stock. Assessment of Maltese demography was based on historical and contemporary catch landings data whilst genetic population structure and regional connectivity patterns were evaluated by examining 175 individuals collected within the central Mediterranean region between 2002 and 2009 using 14 nuclear microsatellite loci. Demographic stock assessment of Maltese E. marginatus’ revealed a 99% decline in catch landings between 1947 and 2009 within the Fisheries Management Zone. A contemporary modest mean size was observed, 3 ± 3 kg, where approximately 17% of the population was juvenile, 68% female/sex-changing and 15% were male with a male-to-female sex ratio of 1:5. Genetic analysis describes the overall population of E. marginatus’ within the Fisheries Management Zone as decreasing in size (ƟH = 2.2), which has gone through a significant size reduction in the past (M = 0.41) and consequently shows signs of moderate inbreeding (FIS = 0.10, p < 0.001) with an estimated effective population size of 130 individuals. Results of spatially explicit Bayesian genetic cluster analysis detected two geographically distinct subpopulations within Malta’s Fisheries Management Zone and that they are connected to a larger network of E. marginatus’ within the Sicily Channel. Results suggest conservation management should be designed to reflect E. marginatus’ within Malta’s Fisheries Management Zone as two management units. PMID:27463811

  5. Gonadotropin-dependent oocyte maturational competence requires activation of the protein kinase A pathway and synthesis of RNA and protein in ovarian follicles of Nibe, Nibea mitsukurii (Teleostei, Sciaenidae)

    USGS Publications Warehouse

    Yoshizaki, G.; Shusa, M.; Takeuchi, T.; Patino, R.

    2002-01-01

    Luteinizing hormone- (LH)-dependent ovarian follicle maturation has been recently described in two stages for teleost fishes. The oocyte's ability to respond to the steroidal maturation-inducing hormone (MIH), also known as oocyte maturational competence (OMC), is acquired during the first stage; whereas the MIH-dependent resumption of meiosis occurs during the second stage. However, studies directly addressing OMC have been performed with a limited number of species and therefore the general relevance of the two-stage model and its mechanisms remain uncertain. In this study, we examined the hormonal regulation of OMC and its basic transduction mechanisms in ovarian follicles of the sciaenid teleost, Nibe (Nibea mitsukurii). Exposure to MIH [17,20??-dihydroxy-4-pregnen-3-one or 17,20??,21-trihydroxy-4-pregnen-3-one] stimulated germinal vesicle breakdown (index of meiotic resumption) in full-grown follicles primed with human chorionic gonadotropin (HCG, an LH-like gonadotropin) but not in those pre-cultured in plain incubation medium. The induction of OMC by HCG was mimicked by protein kinase A (PKA) activators (forskolin and dibutyryl cyclic AMP), and blocked by specific inhibitors of PKA (H89 and H8) as well as inhibitors of RNA (actinomycin D) and protein (cycloheximide) synthesis. Forskolin-induced OMC was also inhibited by actinomycin D and cycloheximide. A strong activator of protein kinase C, PMA, inhibited HCG-dependent OMC. In conclusion, OMC in Nibe ovarian follicles is gonadotropin-dependent and requires activation of the PKA pathway followed by gene transcription and translation events. These observations are consistent with the two-stage model of ovarian follicle maturation proposed for other teleosts, and suggest that Nibe can be used as new model species for mechanistic studies of ovarian follicle differentiation and maturation in fishes.

  6. Cytogenetic comparison between two allopatric populations of Astyanax altiparanae Garutti et Britski, 2000 (Teleostei, Characidae), with emphasis on the localization of 18S and 5S rDNA

    PubMed Central

    Pacheco, Rosiley Berton; da Rosa, Renata; Giuliano-Caetano, Lucia; Júlio Jr., Horácio Ferreira; Dias, Ana Lúcia

    2011-01-01

    Abstract Two populations of Astyanax altiparanae (Garutti & Britski, 2000) of the Água dos Patos stream/SP and lake Igapó/PR were analyzed. All individuals showed 2n = 50, however, different karyotypic formulae were observed. The population of the Água dos Patos stream showed 8m +24sm+6st+12a (NF=88) and the population of lake Igapó, 8m+28sm+4st+10a (NF=90). Nucleolus organizing regions (AgNORs) were observed in the terminal position on the short and long arm of different chromosomes of both populations, showing a variation from 3 to 4 chromosomes. Fluorescent in situ hybridization (FISH) using 18S rDNA probes revealed only one pair of chromosomes with fluorescent signals in the terminal site on the short arm in the Igapó lake population, while the population of Água dos Patos stream showed 4 fluorescence terminal signals, characterizing a system of simple and multiple NORs, respectively. 5S rDNA fluorescent signals were detected in the interstitial position of a pair of chromosomes in the two studied populations. Some AgNOR sites revealed to be GC-rich when stained with Chromomycin A3 (CMA3), however, AT positive regions were not observed. The data obtained show that, despite the conservation of the diploid number and location of 5S DNAr, differences in both the distribution of 18S rDNA and karyotypic formula among the populations were found, thus corroborating the existing data on chromosome variability in Astyanax altiparanae that can be significant for cytotaxonomy in this group. PMID:24260632

  7. Cytogenetic comparison between two allopatric populations of Astyanax altiparanae Garutti et Britski, 2000 (Teleostei, Characidae), with emphasis on the localization of 18S and 5S rDNA.

    PubMed

    Pacheco, Rosiley Berton; da Rosa, Renata; Giuliano-Caetano, Lucia; Júlio, Horácio Ferreira; Dias, Ana Lúcia

    2011-01-01

    Two populations of Astyanax altiparanae (Garutti & Britski, 2000) of the Água dos Patos stream/SP and lake Igapó/PR were analyzed. All individuals showed 2n = 50, however, different karyotypic formulae were observed. The population of the Água dos Patos stream showed 8m +24sm+6st+12a (NF=88) and the population of lake Igapó, 8m+28sm+4st+10a (NF=90). Nucleolus organizing regions (AgNORs) were observed in the terminal position on the short and long arm of different chromosomes of both populations, showing a variation from 3 to 4 chromosomes. Fluorescent in situ hybridization (FISH) using 18S rDNA probes revealed only one pair of chromosomes with fluorescent signals in the terminal site on the short arm in the Igapó lake population, while the population of Água dos Patos stream showed 4 fluorescence terminal signals, characterizing a system of simple and multiple NORs, respectively. 5S rDNA fluorescent signals were detected in the interstitial position of a pair of chromosomes in the two studied populations. Some AgNOR sites revealed to be GC-rich when stained with Chromomycin A3 (CMA3), however, AT positive regions were not observed. The data obtained show that, despite the conservation of the diploid number and location of 5S DNAr, differences in both the distribution of 18S rDNA and karyotypic formula among the populations were found, thus corroborating the existing data on chromosome variability in Astyanax altiparanae that can be significant for cytotaxonomy in this group.

  8. SEM study of the oral cavity of members of the Kyphosidae and Girellidae (Pisces, Teleostei), with remarks on Crenidens (Sparidae), focusing on teeth and taste bud numbers and distribution.

    PubMed

    Fishelson, Lev; Golani, Daniel; Diamant, Ariel

    2014-04-01

    The present study compares dental morphology and taste bud distribution in the oral cavity of four species of the teleost family Kyphosidae, five species of Girellidae and one species of Sparidae. Some of these species are predominantly herbivorous, while others are omnivorous with a high portion of invertebrates in their diets. All the kyphosids feature one row of frontal cusped teeth on their jaws and areas of miniature teeth on the tongue and palate; the girellid species feature 2-5 rows of denticulate teeth, and no teeth inside the oral cavity. The total number of taste buds in the oral cavity is higher in Girella spp. than in the kyphosids, and their number is species-specific, not correlated with fish size. For example, Kyphosus bigibbus of 500mm standard length bears 1780 taste buds, while the kyphosid Neoscorpis lithophilus of 80mm bears 3460. The maximum number of taste buds, 7900, is found in Girella punctata of 60mm standard length, and the minimum number, 1320, in Kyphosus vaigiensis of 175mm. The higher number of taste buds appears to characterize species that possess a more diversified diet. The present study contributes to our understanding of the differences between the two families Kyphosidae and Girellidae. In particular, it relates the eco-morphological adaptations to the type of diet consumed by the various species. Copyright © 2014. Published by Elsevier GmbH.

  9. Effects of orally administered chemotherapeutics (quinine, salinomycin) against Henneguya sp. Thelohán, 1892 (Myxozoa: Myxobolidae), a gill parasite in the tapir fish Gnathonemus petersii Günther, 1862 (Teleostei).

    PubMed

    Dohle, Angelika; Schmahl, Günter; Raether, Wolfgang; Schmidt, Hartmut; Ritter, Günter

    2002-09-01

    When given orally, quinine or salinomycin cause irreversible damage to the plasmodial developmental stages of Henneguya sp., a gill parasite in the tapir fish Gnathonemus petersii. Naturally infected tapir fish measured 75-169 mm in total length and their total weight ranged over 4.3-11.7 g. The fish bore 7-77 plasmodia in their gill arches. Medicinal food containing either quinine (5 g/1000 g food) or salinomycin (0.075 g/1000 g food) was given once a day to naturally infected fish in a food chain via water fleas ( Daphnia spp) for a period of 3, 6, or 9 days. From the monitored feeding of the tapir fish and weight determinations of the water fleas, it was calculated that gross uptake was 18.5 micro g/kg body weight fish daily for pure salinomycin and was 1.25 mg/kg body weight daily for quinine. After the end of the experiments, the fish were sacrificed and the plasmodia were carefully prepared from the gill arches and processed for transmission electron microscopy. As seen by ultrastructure investigations, for both substances the grade of damage in the parasites correlated positively with the period of application. When quinine was given for a 3-day period, the trophozoite ecto- and endoplasm exerted numerous vacuoles, caused by the drug, and the presporogonous and the pansporoblastic stages were malformed. Following a 6-day period, numerous abortive polar capsules were found in the trophozoite cytoplasm. To a large extent, the limiting membranes of the polaroblasts and valvogenic cells were destroyed. In addition, deep clefts between the polaroblasts, the valvogenic cells and between the two sporoblasts were observed. Following a 9-day treatment, all damage increased and, in addition, generative cells and two-cell stages were no longer detectable. As a first sign for the effects of salinomycin, following a 3-day treatment, a shrinking of the whole plasmodia occurred and the sutures in the pansporoblasts were enlarged. The polar capsules were malformed and the zonar structures of the polar filament were no longer detectable. The sporoplasmosomes were more electron-pale than those of the control samples. After a 9-day treatment, the pansporoblasts were completely destroyed. Under the experimental conditions chosen, both compounds were very well tolerated by the fishes.

  10. Saturnius minutus n. sp. and S. dimitrovi n. sp. (Digenea: Hemiuridae) from Mugil cephalus L. (Teleostei: Mugilidae), with a multivariate morphological analysis of the Mediterranean species of Saturnius Manter, 1969.

    PubMed

    Blasco-Costa, I; Pankov, P; Gibson, D I; Balbuena, J A; Raga, J A; Sarabeev, V L; Kostadinova, A

    2006-09-01

    Three species of the bunocotyline genus Saturnius Manter, 1969 are described from the stomach lining of mugilid fishes of the Mediterranean and Black Seas. Two of the species are new: S. minutus n. sp. occurs in Mugil cephalus off the Mediterranean coast of Spain; and S. dimitrovi n. sp., a parasite of M. cephalus off the Bulgarian Black Sea coast and the Spanish Mediterranean coast, was originally described as S. papernai by Dimitrov et al. (1998). In addition, S. papernai Overstreet, 1977 is redescribed from M. cephalus off the Spanish Mediterranean coast and from Liza aurata and L. saliens off the Bulgarian Black Sea coast. The three species are distinguished morphometrically using univariate and multivariate analyses. These results were verified using Linear Discriminant Analysis which correctly allocated all specimens to their species designations based on morphology (i.e. 100% successful classification rate) and assigned almost all specimens to the correct population (locality). The following variables were selected for optimal separation between samples: the length of the forebody, ventral sucker and posterior testis, the length and width of the posteriormost pseudosegment, and the width of the muscular flange at ventral sucker level.

  11. Effects of parental number and duration of the breeding period on the effective population size and genetic diversity of a captive population of the endangered Tokyo bitterling Tanakia tanago (Teleostei: Cyprinidae).

    PubMed

    Kubota, Hitoshi; Watanabe, Katsutoshi

    2012-01-01

    The maintenance of genetic diversity is one of the chief concerns in the captive breeding of endangered species. Using microsatellite and mtDNA markers, we examined the effects of two key variables (parental number and duration of breeding period) on effective population size (N(e) ) and genetic diversity of offspring in an experimental breeding program for the endangered Tokyo bitterling, Tanakia tanago. Average heterozygosity and number of alleles of offspring estimated from microsatellite data increased with parental number in a breeding aquarium, and exhibited higher values for a long breeding period treatment (9 weeks) compared with a short breeding period (3 weeks). Haplotype diversity in mtDNA of offspring decreased with the reduction in parental number, and this tendency was greater for the short breeding period treatment. Genetic estimates of N(e) obtained with two single-sample estimation methods were consistently higher for the long breeding period treatment with the same number of parental fish. Average N(e) /N ratios were ranged from 0.5 to 1.4, and were high especially in the long breeding period with small and medium parental number treatments. Our results suggest that the spawning intervals of females and alternative mating behaviors of males influence the effective size and genetic diversity of offspring in bitterling. To maintain the genetic diversity of captive T. tanago, we recommend that captive breeding programs should be conducted for a sufficiently long period with an optimal level of parental density, as well as using an adequate number of parents. © 2011 Wiley Periodicals, Inc.

  12. Ligophorus species (Monogenea: Ancyrocephalidae) from Mugil cephalus (Teleostei: Mugilidae) off Morocco with the description of a new species and remarks about the use of Ligophorus spp. as biological markers of host populations.

    PubMed

    El Hafidi, Fouzia; Rkhami, Ouafae Berrada; de Buron, Isaure; Durand, Jean-Dominique; Pariselle, Antoine

    2013-11-01

    Gill monogenean species of Ligophorus Euzet et Suriano, 1977 were studied from the teleost Mugil cephalus Linneaus (Mugilidae) from the Mediterranean and Atlantic coasts of Morocco. We report the presence of L. mediterraneus from both the Mediterranean and Atlantic coast and L. cephali and L. maroccanus sp. n. from the Atlantic coast only. The latter species, which is described herein as new, resembles L. guanduensis but differs from this species mainly in having a shorter penis compared to the accessory piece, a proportionally longer extremity of the accessory piece and a less developed heel. The utility of Ligophorus spp. as markers of cryptic species of the complex M. cephalus is discussed in the context of species diversity and geographical distribution of these monogeneans on this host around the world. Presence of different species of Ligophorus on M. cephalus sensu stricto from the Atlantic and Mediterranean coast of Morocco demonstrates the usefulness of these species as fine resolution markers of genetic populations of their host, which are known to inhabit those coasts.

  13. Effects of temperature on sustained swimming performance and swimming kinematics of the chub mackerel Scomber japonicus.

    PubMed

    Dickson, Kathryn A; Donley, Jeanine M; Sepulveda, Chugey; Bhoopat, Lisa

    2002-04-01

    The effects of a 6 degrees C difference in water temperature on maximum sustained swimming speed, swimming energetics and swimming kinematics were measured in the chub mackerel Scomber japonicus (Teleostei: Scombridae), a primarily coastal, pelagic predator that inhabits subtropical and temperate transition waters of the Atlantic, Pacific and Indian Oceans. New data for chub mackerel acclimated to 18 degrees C are compared with published data from our laboratory at 24 degrees C. Twelve individuals acclimated to each of two temperatures (15.6-26.3 cm fork length, FL, and 34-179 g at 18 degrees C; 14.0-24.7 cm FL and 26-156 g at 24 degrees C) swam at a range of speeds in a temperature-controlled Brett-type respirometer, at the respective acclimation temperature. At a given fish size, the maximum speed that S. japonicus was able to maintain for a 30-min period, while swimming steadily using slow, oxidative locomotor muscle (U(max,c)), was significantly greater at 24 than at 18 degrees C (52.5-97.5 cm s(-1) at 18 degrees C and 70-120 cm s(-1) at 24 degrees C). At a given speed and fish size, the rate of oxygen consumption (VO(2)) was significantly higher at 24 than at 18 degrees C because of a higher net cost of transport (1073-4617 J km(-1) kg(-1) at 18 degrees C and 2708-14895 J km(-1) kg(-1) at 24 degrees C). Standard metabolic rate, calculated by extrapolating the logO(2) versus swimming speed relationship to zero speed, did not vary significantly with temperature or fish mass (126.4+/-67.2 mg O(2) h(-1) kg(-1) at 18 degrees C and 143.2+/-80.3 mg O(2) h(-1) kg(-1) at 24 degrees C; means +/- S.D., N=12). Swimming kinematics was quantified from high-speed (120 Hz) video recordings analyzed with a computerized, two-dimensional motion-analysis system. At a given speed and fish size, there were no significant effects of temperature on tail-beat frequency, tail-beat amplitude or stride length, but propulsive wavelength increased significantly with temperature as a result

  14. Neotropical Monogenoidea 37. Redescription of Gyrodactylus superbus (Szidat, 1973) comb. n. and description of two new species of Gyrodactylus (Gyrodactylidea: Gyrodactylidae) from Corydoras paleatus and C. ehrhardti (Teleostei: Siluriformes: Callichthyidae) of Southern Brazil.

    PubMed

    Popazoglo, F; Boeger, W A

    2000-01-01

    Two new species of Gyrodactylus (Gyrodactylidae) are described from Corydoras paleatus (Jenyns) and Corydoras ehrhardti Steindachner (Callichthyidae) of Rio Piraquara, Municipality of Piraquara, near Curitiba, Paraná, Brazil: Gyrodactylus anisopharynx sp. n. and Gyrodactylus samirae sp. n. These species are unique among the known Neotropical species of Gyrodactylus by the combination of several characters. Gyrodactylus anisopharynx is characterised by having hooks with point evenly curved, toe moderately pointed, round convex heel, straight sloping shelf, superficial bar with anterolateral projections and male copulatory organ armed with two rows of spinelets. Two variants of G. anisopharynx, of distinct pharynx size, are recognised: forma "large-pharynx" and forma "small-pharynx". Gyrodactylus samirae is characterised by having hook with straight shaft, short slightly recurved point, truncate toe, trapezoidal heel, shelf slightly concave, orthogonal to shaft; anchors with relatively short superficial root; superficial bar with extremities lightly expanded; and male copulatory organ armed with two rows of spinelets. Paragyrodactyloides superbus (Szidat, 1973) is redescribed and transferred to Gyrodactylus based on examination of type and new specimens. Features previously considered as diagnostic for the genus are misinterpretations or primitive characters for Gyrodactylus spp.

  15. Comparative sequence analysis of the complete set of 40S ribosomal proteins in the Senegalese sole (Solea senegalensis Kaup) and Atlantic halibut (Hippoglossus hippoglossus L.) (Teleostei: Pleuronectiformes): phylogeny and tissue- and development-specific expression.

    PubMed

    Manchado, Manuel; Infante, Carlos; Asensio, Esther; Cañavate, Jose Pedro; Douglas, Susan E

    2007-07-03

    Ribosomal proteins (RPs) are key components of ribosomes, the cellular organelle responsible for protein biosynthesis in cells. Their levels can vary as a function of organism growth and development; however, some RPs have been associated with other cellular processes or extraribosomal functions. Their high representation in cDNA libraries has resulted in the increase of RP sequences available from different organisms and their proposal as appropriate molecular markers for phylogenetic analysis. The development of large-scale genomics of Senegalese sole (Solea senegalensis) and Atlantic halibut (Hippoglossus hippoglossus), two commercially important flatfish species, has made possible the identification and systematic analysis of the complete set of RP sequences for the small (40S) ribosome subunit. Amino acid sequence comparisons showed a high similarity both between these two flatfish species and with respect to other fish and human. EST analysis revealed the existence of two and four RPS27 genes in Senegalese sole and Atlantic halibut, respectively. Phylogenetic analysis clustered RPS27 in two separate clades with their fish and mammalian counterparts. Steady-state transcript levels for eight RPs (RPS2, RPS3a, RPS15, RPS27-1, RPS27-2, RPS27a, RPS28, and RPS29) in sole were quantitated during larval development and in tissues, using a real-time PCR approach. All eight RPs exhibited different expression patterns in tissues with the lowest levels in brain. On the contrary, RP transcripts increased co-ordinately after first larval feeding reducing progressively during the metamorphic process. The genomic resources and knowledge developed in this survey will provide new insights into the evolution of Pleuronectiformes. Expression data will contribute to a better understanding of RP functions in fish, especially the mechanisms that govern growth and development in larvae, with implications in aquaculture.

  16. Fish as a proxy for African paleogeography: results from both extant and fossil taxa and prospects to constrain faunal exchange pathway through time

    NASA Astrophysics Data System (ADS)

    Otero, Olga; Joordens, Josephine; Dettai, Agnès; Christ, Leemans; Pinton, Aurélie

    2016-04-01

    : relationships between Chad and neighbouring basins throughout the Mio-Pliocene. Palaeobiogeography, Palaeoclimatology, Palaeoecology, 274 (2009): 134-139. [5] Argyriou T., Otero O., Pavlakis P., Boaz N.T. 2012 - Description and paleobiogeographical implications of new Semlikiichthys (Teleostei, Perciformes) fish material from the Late Miocene deposits of Sahabi, Libya. Geobios, 45(2012): 429-436. [6] Joordens J (Pi) - Coastal origins? A biogeographical model for mominin evolution and dispersal in Africa between 5 and 2.5 million years ago.