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Are characiform Fishes Gondwanan in Origin? Insights from a Time-Scaled Molecular Phylogeny of the Citharinoidei (Ostariophysi: Characiformes)  [PDF]
Jairo Arroyave, John S. S. Denton, Melanie L. J. Stiassny
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0077269
Abstract: Fishes of the order Characiformes are a diverse and economically important teleost clade whose extant members are found exclusively in African and Neotropical freshwaters. Although their transatlantic distribution has been primarily attributed to the Early Cretaceous fragmentation of western Gondwana, vicariance has not been tested with temporal information beyond that contained in their fragmentary fossil record and a recent time-scaled phylogeny focused on the African family Alestidae. Because members of the suborder Citharinoidei constitute the sister lineage to the entire remaining Afro-Neotropical characiform radiation, we inferred a time-calibrated molecular phylogeny of citharinoids using a popular Bayesian approach to molecular dating in order to assess the adequacy of current vicariance hypotheses and shed light on the early biogeographic history of characiform fishes. Given that the only comprehensive phylogenetic treatment of the Citharinoidei has been a morphology-based analysis published over three decades ago, the present study also provided an opportunity to further investigate citharinoid relationships and update the evolutionary framework that has laid the foundations for the current classification of the group. The inferred chronogram is robust to changes in calibration priors and suggests that the origins of citharinoids date back to the Turonian (ca 90 Ma) of the Late Cretaceous. Most modern citharinoid genera, however, appear to have originated and diversified much more recently, mainly during the Miocene. By reconciling molecular-clock- with fossil-based estimates for the origins of the Characiformes, our results provide further support for the hypothesis that attributes the disjunct distribution of the order to the opening of the South Atlantic Ocean. The striking overlap in tempo of diversification and biogeographic patterns between citharinoids and the African-endemic family Alestidae suggests that their evolutionary histories could have been strongly and similarly influenced by Miocene geotectonic events that modified the landscape and produced the drainage pattern of Central Africa seen today.
Nuclear DNA content of thirty species of Neotropical fishes
Carvalho, Margarida Lima;Oliveira, Claudio;Foresti, Fausto;
Genetics and Molecular Biology , 1998, DOI: 10.1590/S1415-47571998000100009
Abstract: the present paper reports nuclear dna content in 30 neotropical freshwater fish species and summarizes the data on other neotropical species presented in the literature. among neotropical fishes, the nuclear dna content ranges from 1.04 ± 0.09 pg/nucleus in corydoras cf. simulatus (2n = 62) to 248.0 pg/nucleus in lepidosiren paradoxa (2n = 38). a general analysis of the data obtained in the present study for each species showed that dna measurements were practically constant at the individual level, while significant differences were observed among individuals of the same population. this observation was valid for all species analyzed and was more evident in those species that presented other karyotypic particularities such as sex chromosomes or supernumerary chromosomes. the importance of changes in nuclear dna content in the evolutionary process of neotropical fishes is discussed.
Nuclear DNA content of thirty species of Neotropical fishes  [cached]
Carvalho Margarida Lima,Oliveira Claudio,Foresti Fausto
Genetics and Molecular Biology , 1998,
Abstract: The present paper reports nuclear DNA content in 30 Neotropical freshwater fish species and summarizes the data on other Neotropical species presented in the literature. Among Neotropical fishes, the nuclear DNA content ranges from 1.04 ± 0.09 pg/nucleus in Corydoras cf. simulatus (2n = 62) to 248.0 pg/nucleus in Lepidosiren paradoxa (2n = 38). A general analysis of the data obtained in the present study for each species showed that DNA measurements were practically constant at the individual level, while significant differences were observed among individuals of the same population. This observation was valid for all species analyzed and was more evident in those species that presented other karyotypic particularities such as sex chromosomes or supernumerary chromosomes. The importance of changes in nuclear DNA content in the evolutionary process of Neotropical fishes is discussed.
Feeding association between benthic and nektonic Neotropical stream fishes
Teresa, Fabrício Barreto;Carvalho, Fernando Rogério;
Neotropical Ichthyology , 2008, DOI: 10.1590/S1679-62252008000100013
Abstract: following behaviour among neotropical stream fishes have been scarcely reported. this type of feeding association was observed in a small stream in the upper rio paraná system between the catfish, aspidoras fuscoguttatus, acting as a nuclear species, and knodus moenkhausii, poecilia reticulata, and astyanax altiparanae as follower species. aspidoras fuscoguttatus individuals dug in the bottom during feeding, causing sediment suspension. their followers picked food items in the "cloud" of suspended particles. food items of sediment are no longer consumed by the catfish when in suspension, but are still available for k. moenkhausii, p. reticulata and a. altiparanae. following behaviour is an alternative feeding tactic for these species, which reinforces the general idea of behavioural plasticity among follower species.
Swimming performance of the migratory Neotropical fish Leporinus reinhardti (Characiformes: Anostomidae)
Santos, Hersília de Andrade e;Pompeu, Paulo dos Santos;Martinez, Carlos Barreira;
Neotropical Ichthyology , 2007, DOI: 10.1590/S1679-62252007000200007
Abstract: the fishways built in latin america were mainly based on those used in the northern hemisphere for passing salmonids upstream. however, the swimming capacity in terms of speed and endurance is a major factor concerning the design of a fishway, and this information is not available for migratory neotropical fish species. therefore, studies on swimming performance of neotropical species is fundamental. the aim of this study was to estimate the critical, sustained and prolonged speeds for the piau-três-pintas leporinus reinhardti, and to evaluate the influence of water temperature on the swimming performance of the species. variable (increasing) and fixed velocity tests were performed in a respirometer. when compared to other species whose critical speed data are available, the piau showed higher speeds, for a given total length. fatigue times per prolonged speed class were estimated as well as prolonged speed per fatigue time class. the changing point from sustained to prolonged swimming was estimated to occur approximately at a speed of seven body-lengths per second (1.12 m/s for an individual with 16 cm total length: the first maturation length). in spite of the great swimming performance of piau, the adoption of efficient directives in fishway projects to allow the passage of neotropical ichthyofauna, will depend on a more detailed analysis of the swimming capacity of different species.
Nuclear DNA content determination in Characiformes fish (Teleostei, Ostariophysi) from the Neotropical region
Carvalho, Margarida Lima;Oliveira, Claudio;Navarrete, Maria Clara;Froehlich, Otávio;Foresti, Fausto;
Genetics and Molecular Biology , 2002, DOI: 10.1590/S1415-47572002000100010
Abstract: in the present study, nuclear dna content was analyzed in 53 species of characiformes fish from the neotropical region. diploid number ranged from 2n = 48 in astyanax fasciatus, gymnocorymbus ternetzi and hyphessobrycon griemi to 2n = 102 in potamorhina squamoralevis, with a modal number of 54 chromosomes. nuclear dna content ranged from 1.70 ± 0.04 pg of dna per diploid nucleus in acestrorhynchus pantaneiro to 3.94 ± 0.09 pg in tetragonopterus chalceus. a general analysis showed a mean value of 2.9 pg of dna per diploid nucleus. very similar dna content values were observed in the species of the family cynodontidae which showed a variation of 3% between the two genera studied. small variations were observed between populations of gymnocorymbus ternetzi, astyanax fasciatus and moenkhausia sanctaefilomenae (characidae, tetragonopterinae). the subfamilies tetragonopterinae and acestrorhynchinae (characidae) presented the widest range, about 96%. even in those families in which diploid number and karyotypic formulae were conserved such as the families anostomidae, curimatidae, and prochilodontidae, episodes leading to losses or gains of genetic material became fixed in their evolutionary history.
Nuclear DNA content determination in Characiformes fish (Teleostei, Ostariophysi) from the Neotropical region
Carvalho Margarida Lima,Oliveira Claudio,Navarrete Maria Clara,Froehlich Otávio
Genetics and Molecular Biology , 2002,
Abstract: In the present study, nuclear DNA content was analyzed in 53 species of Characiformes fish from the Neotropical region. Diploid number ranged from 2n = 48 in Astyanax fasciatus, Gymnocorymbus ternetzi and Hyphessobrycon griemi to 2n = 102 in Potamorhina squamoralevis, with a modal number of 54 chromosomes. Nuclear DNA content ranged from 1.70 ± 0.04 pg of DNA per diploid nucleus in Acestrorhynchus pantaneiro to 3.94 ± 0.09 pg in Tetragonopterus chalceus. A general analysis showed a mean value of 2.9 pg of DNA per diploid nucleus. Very similar DNA content values were observed in the species of the family Cynodontidae which showed a variation of 3% between the two genera studied. Small variations were observed between populations of Gymnocorymbus ternetzi, Astyanax fasciatus and Moenkhausia sanctaefilomenae (Characidae, Tetragonopterinae). The subfamilies Tetragonopterinae and Acestrorhynchinae (Characidae) presented the widest range, about 96%. Even in those families in which diploid number and karyotypic formulae were conserved such as the families Anostomidae, Curimatidae, and Prochilodontidae, episodes leading to losses or gains of genetic material became fixed in their evolutionary history.
Spermatic characteristics and sperm evolution on the subfamily Stevardiinae (Ostariophysi: Characiformes: Characidae)
Baicere-Silva, Clarianna Martins;Ferreira, Katiane M.;Malabarba, Luiz R.;Benine, Ricardo C.;Quagio-Grassiotto, Irani;
Neotropical Ichthyology , 2011, DOI: 10.1590/S1679-62252011005000014
Abstract: the monophyly and phylogenetic relationships among the members of clade a characids (sensu malabarba & weitzman), later redefined and named as the stevardiinae (sensu mirande), have been primarily supported by traditional morphological and molecular data. herein were examined, described and compared spermiogenesis and sperm ultrastructure of 12 species of the genera boehlkea, bryconacidnus, bryconamericus, creagrutus, cyanocharax, hemibrycon, knodus, odontostoechus, piabina, and rhinobrycon in order to evaluate possible phylogenetic signals and their potential use in recovering relationships of the stevardiinae. all examined species demonstrated a nuclear rotation equal or less than 95o resulting in a lateral position of the double nuclear fossa and flagellum. in all species, sperm nuclei are slightly elongate toward the flagellum, the proximal centriole is partially inside the nuclear fossa and lies anterior and oblique to the distal centriole, and the midpiece is short and strongly asymmetric. all species analyzed herein and other species previously examined for these systems in the stevardiinae share homologous sperm characteristics as evidenced by spermiogenesis, further supporting the monophyly of this clade. spermatozoa of the stevardiinae further show three morphotypes (m1, m2, m3) of arrangement of centrioles, flagellum, nucleus and midpiece, hypothesized as successively derived in a series of transformation from the most basal morphotype (m1).
Spermatic characteristics and sperm evolution on the subfamily Stevardiinae (Ostariophysi: Characiformes: Characidae)  [cached]
Clarianna Martins Baicere-Silva,Katiane M. Ferreira,Luiz R. Malabarba,Ricardo C. Benine
Neotropical Ichthyology , 2011,
Abstract: The monophyly and phylogenetic relationships among the members of Clade A characids (sensu Malabarba & Weitzman), later redefined and named as the Stevardiinae (sensu Mirande), have been primarily supported by traditional morphological and molecular data. Herein were examined, described and compared spermiogenesis and sperm ultrastructure of 12 species of the genera Boehlkea, Bryconacidnus, Bryconamericus, Creagrutus, Cyanocharax, Hemibrycon, Knodus, Odontostoechus, Piabina, and Rhinobrycon in order to evaluate possible phylogenetic signals and their potential use in recovering relationships of the Stevardiinae. All examined species demonstrated a nuclear rotation equal or less than 95o resulting in a lateral position of the double nuclear fossa and flagellum. In all species, sperm nuclei are slightly elongate toward the flagellum, the proximal centriole is partially inside the nuclear fossa and lies anterior and oblique to the distal centriole, and the midpiece is short and strongly asymmetric. All species analyzed herein and other species previously examined for these systems in the Stevardiinae share homologous sperm characteristics as evidenced by spermiogenesis, further supporting the monophyly of this clade. Spermatozoa of the Stevardiinae further show three morphotypes (M1, M2, M3) of arrangement of centrioles, flagellum, nucleus and midpiece, hypothesized as successively derived in a series of transformation from the most basal morphotype (M1). A monofilia e filogenia dos membros do Clado A (sensu Malabarba & Weitzman), mais tarde redefinido e nomeado Stevardiinae (sensu Mirande), é suportada por dados morfológicos e moleculares. Aqui s o examinadas, descritas e comparadas a espermiogênese e ultraestrutura do espermatozoide de 12 espécies dos gêneros Boehlkea, Bryconacidnus, Bryconamericus, Creagrutus, Cyanocharax, Hemibrycon, Knodus, Odontostoechus, Piabina e Rhinobrycon, a fim de avaliar possíveis sinais filogenéticos e seu uso potencial no estudo de rela es filogenéticas em Stevardiinae. Em todas as espécies examinadas observa-se uma rota o nuclear igual ou menor que 95o, resultando em uma posi o lateral da fossa nuclear dupla e do flagelo. Em todas as espécies o núcleo do espermatozoide é alongado em dire o ao flagelo, o centríolo proximal é anterior e oblíquo ao centríolo distal e localiza-se parcialmente inserido na fossa nuclear, e a pe a intermediária é pequena e fortemente assimétrica. Todas as espécies de Stevardiinae analisadas aqui e outras analisadas previamente compartilham características homólogas dos espermatozoides evidenci
Reynolds shear-stress and velocity: positive biological response of neotropical fishes to hydraulic parameters in a vertical slot fishway
Duarte, Bernardo Alan de Freitas;Ramos, Isabella Cristina Resende;Santos, Hersília de Andrade e;
Neotropical Ichthyology , 2012, DOI: 10.1590/S1679-62252012000400014
Abstract: the barriers created by dams can cause negative impacts to aquatic communities, and migratory fish species are directly affected. fishways have been developed to allow the upstream passage of fishes through dams. in brazil, after the implementation of environmental laws, these structures have been built based on european and american fishway designs. studies have shown selectivity for different neotropical fishes in some brazilian fishways, and the main challenge has been to promote upstream passage of a large number of diverse fish species. the patterns of flow circulation within the fish ladder may explain fish selectivity although few studies detail the fish response to hydraulic characteristics of fish ladder flow. this paper presents a laboratory study, where a vertical slot fishway was built in a hydraulic flume and the behavior of two neotropical fish species (leporinus reinhardti and pimelodus maculatus) were analyzed. the structure of flow was expressed in terms of mean velocity, reynolds shear-stress and velocity fluctuation fields. the individuals of leporinus reinhardti had higher passage success than pimelodus maculatus in the laboratory flume. both species preferred areas of low to zero reynolds shear-stress values. in addition, different preferences were observed for these species concerning the horizontal components of velocity fluctuation.
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