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The Neotropics harbors a megadiverse ichthyofauna comprising over 6300 species with approximately 80% in just three taxonomic orders within the clade Characiphysi. This highly diverse group has evolved in tropical South America over tens to hundreds of millions of years influenced mostly by re‐arrangements of river drainages in lowland and upland systems. In this study, we investigate patterns of spatial diversification in Neotropical freshwater fishes in the family Curimatidae, a species‐rich clade of the order Characiformes. Specifically, we examined ancestral areas, dispersal events, and shifts in species richness using spatially explicit biogeographic and macroevolutionary models to determine whether lowlands–uplands serve as museums or cradles of diversification for curimatids. We used fossil information to estimate divergence times in BEAST, multiple time‐stratified models of geographic range evolution in BioGeoBEARS, and alternative models of geographic state‐dependent speciation and extinction in GeoHiSSE. Our results suggest that the most recent common ancestor of curimatids originated in the Late Cretaceous likely in lowland paleodrainages of northwestern South America. Dispersals from lowland to upland river basins of the Brazilian and Guiana shields occurred repeatedly across independently evolving lineages in the Cenozoic. Colonization of upland drainages was often coupled with increased rates of net diversification in species‐rich genera such as Cyphocharax and Steindachnerina. Our findings demonstrate that colonization of novel aquatic environments at higher elevations is associated with an increased rate of diversification, although this pattern is clade‐dependent and driven mostly by allopatric speciation. Curimatids reinforce an emerging perspective that Amazonian lowlands act as a museum by accumulating species along time, whereas the transitions to uplands stimulate higher net diversification rates and lineage diversification., The time‐calibrated molecular phylogeny and geographic range evolution of the Neotropical family Curimatidae show a Late Cretaceous origin in lowland basins of South America with subsequent colonization to upland basins at multiple times during the Cenozoic. Dispersal events, especially in the species‐rich genera Cyphocharax and Steindachnerina, were prevalent in the Brazilian Shield during the Paleogene and Neogene. Colonization of uplands increased net diversification rates in some curimatid subclades.

The fish family Cynodontidae belongs to the superfamily Curimatoidea, together with the Hemiodontidae, Serrasalmidae, Parodontidae, Prochilodontidae, Chilodontidae, Curimatidae, and Anostomidae. The majority of the species of this superfamily that have been analyzed to date have a diploid chromosome number of 2n = 54. Differentiated sex chromosomes (with female heterogamety) have been observed only in the Prochilodontidae, Parodontidae, and Anostomidae. The present study provides the first description of differentiated sex chromosomes in the cynodontid species Cynodon gibbus, which has a ZZ/ZW system, and shows that repetitive DNA has played a fundamental role in the differentiation of these sex chromosomes.

The knowledge of the Costa Rican freshwater fish fauna continues to grow given the discovery of new taxa, the recognition of taxa resurrected from synonymy and the corroboration of new country records and new range extensions. Moreover, recent advances in the understanding of the phylogenetic relationships and status of many supraspecific groups have led to numerous taxonomic and nomenclatural changes. Given this, the purpose of this paper is to update the known composition, distribution and clasification of the Costa Rican freshwater fish fauna taking as reference the most recent list for the country published by Angulo et al. (2013). A total of 23 new country records (i.e., species; distributed in 17 families and 21 genera), 33 new range extensions (distributed in 20 families and 30 genera) and several nomenclatural changes are reported, illustrated and discussed here. An updated and annotated checklist of the freshwater fishes of the country (including data for a total of 283 species, 13 of which are exotic, distributed in two classes, 27 orders, 55 families and 136 genera) is also provided.

Family Curimatidae Gill, 1858. Toothless Characiforms; Plateadas. 1 G, 1 S., Published as part of Angulo, Arturo, 2021, New records and range extensions to the Costa Rican freshwater fish fauna, with an updated checklist, pp. 1-72 in Zootaxa 5083 (1) on page 24, DOI: 10.11646/zootaxa.5083.1.1, http://zenodo.org/record/5800630

Cyphocharax magdalenae (Steindachner, 1878). Carp Headstander; Sardina, Capani, Capaniz, Carpa, Plateada, Plateadita. Distribution: Global: Central and South America; from southern Costa Rica to western Colombia, Atlantic and Pacific drainages; Costa Rica: Co (Pacific), 5��� 100 m.a.s.l., Pri, Pot. Occurrence and conservation status: Nat, LC. References: Bussing (1966: 221, as Curimata magdalenae ���synonym; brief description and information on distribution), Bussing (1987: 97, as Curimata magdalenae ���synonym; 1998: 126; brief description, including illustrations and an identification key, information on distribution, with a map, and ecology) and Angulo et al. (2013: 991; listed, including taxonomic information and distributional data)., Published as part of Angulo, Arturo, 2021, New records and range extensions to the Costa Rican freshwater fish fauna, with an updated checklist, pp. 1-72 in Zootaxa 5083 (1) on page 24, DOI: 10.11646/zootaxa.5083.1.1, http://zenodo.org/record/5800630

Made available in DSpace on 2022-04-29T08:30:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-03-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Purpose: We describe two new Henneguya spp. (Myxobolidae) found parasitizing Cyphocharax modestus from Pardo river, Paraná river basin, municipality of Botucatu, São Paulo State, Brazil: Henneguya fastigata n. sp. from gill lamellae and Henneguya pardensis n. sp. from gill arches. We based the descriptions on myxospore morphology, histology, and small subunit ribosomal DNA sequences. Methods: In this investigation, 50 specimens of Cyphocharax modestus were examined between July and December 2020 for myxozoan infections. Morphological characterization was based on the mature myxospores. The small subunit ribosomal DNA sequences were used for molecular and phylogenetic study. Results: Phylogenetic analysis provided the evolutionary position of these new species with other myxobolids species. Myxospores of the two species had similar morphology and morphometrics, but differed in spore body width and length, and ssrDNA sequences differed by 7.2%. These data supported the diagnosis of the parasites as distinct and novel species. The phylogenetic analysis showed a well-supported subclade formed by species that parasitize curimatid fishes, with Henneguya gilbert as a sister species of Henneguya fastigata n. sp., and Henneguya pardensis n. sp. as a sister species of both species. Conclusion: Our analysis was consistent with previous studies suggesting that orders and families of the hosts are strongly correlated with phylogenetic signals in the Myxobolidae. These are the first species of myxozoans described in the Pardo river. Laboratory of Parasitology of Wild Animals Division of Parasitology Institute of Biosciences Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), R. Prof. Dr. Antônio Celso Wagner Zanin, 250, Rubião Junior, SP Programa de Pós-Graduação Em Análise de Sistemas Ambientais Centro Universitário CESMAC, AL Laboratory of Parasitology of Wild Animals Division of Parasitology Institute of Biosciences Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), R. Prof. Dr. Antônio Celso Wagner Zanin, 250, Rubião Junior, SP FAPESP: 2019/19060-0 FAPESP: 2019/26831-2 FAPESP: 2020/05412-9 CNPq: 309125/2017-0

Cyphocharax modestus (Fernández-Yépez, 1948) Material examined. BRAZIL – São Paulo • Iperó, Verde River; 23°26.35′S, 047°35.28′W; 570 m alt., 13.VI. 2017; W.S. Smith and L. Halcsik leg.; cast nets; MZUSP 115235 (7 spec., 155.0−180.0 mm SL). Identification. Body deep; mouth terminal; premaxilla, dentary and maxilla without teeth. Lateral line with 35–37 pored scales; transversal series above lateral line with 6–6½ scale rows and below with 5–6½ scale rows. Dorsal fin with 10 rays, pectoral fin with 10–12, pelvic fin with 10, anal fin with 8–11 and caudal fin with 21 rays. Ground color silvery; dark brown inconspicuous longitudinal band along lateral line to distal margin of median caudal-fin rays, larger on caudal peduncle; hyaline fins (Batista-Silva et al. 2018)., Published as part of Smith, Welber Senteio, Halcsik, Leticia, Biagioni, Renata Cassemiro, Pinheiro, Lúcio Antônio Stefani & Severino Stefani, Marta, 2021, An updated list of the ichthyofauna of Ipanema National Forest, São Paulo, Brazil, pp. 827-840 in Check List 17 (3) on page 836, DOI: 10.15560/17.3.827

Steindachnerina insculpta (Fernández-Yépez, 1948) Material examined. BRAZIL – São Paulo • Iperó, Ipanema River; 23°22.40′S, 049°38.51′W; 560 m alt.; 12.I.2012; W.S. Smith and L. Halcsik leg.; hand nets; MZUSP 115238 (6 spec., 80.0−90.0 mm SL). Identification. Body deep; mouth terminal; premaxilla, dentary, and maxilla without teeth; lateral line with 33– 35 pored scales; transversal series above lateral line with 5–5½ scale rows and below with 4½–5½. Dorsal fin with 10 rays, pectoral fin with 12–14, pelvic fin with 13 rays, anal fin with 12–14, and caudal fin with 21 rays. Ground color silvery; black conspicuous longitudinal stripe along lateral line to distal margin of median caudal-fin rays, larger on caudal peduncle; yellowish fins; dorsal-fin black blotch on the base of median rays, sometimes little conspicuous (Batista-Silva et al. 2018)., Published as part of Smith, Welber Senteio, Halcsik, Leticia, Biagioni, Renata Cassemiro, Pinheiro, Lúcio Antônio Stefani & Severino Stefani, Marta, 2021, An updated list of the ichthyofauna of Ipanema National Forest, São Paulo, Brazil, pp. 827-840 in Check List 17 (3) on page 836, DOI: 10.15560/17.3.827

Recent expeditions to northwestern Argentina revealed the presence of an unknown species of Curimatidae for the Bermejo river basin. The morphometric and meristic analyses of these specimens allow us to identify them as Steindachnerina insculpta (Fernández-Yépez, 1948), which is here reported for the first time in Argentina

A study on the nematode parasites of nine species of freshwater fishes from Peixe River São Paulo, State, Brazil. was conducted. Fish were collected between February 2010 and March 2011 and the following species were found: Procamallanus (Spirocamallanus) inopinatus and Contracaecum sp. (larvae) in Astyanax altiparanae; Contracaecum sp. (larvae), Dioctophyma renale (larvae), Philometroides caudata, P. (Spirocamallanus) inopinatus, P. (Spirocamallanus) neocaballeroi (larvae) and P. (Spirocamallanus) saofranciscensis in Acestrorhynchus lacustris; Contracaecum sp. (larvae), Guyanema sp., Hysterothylacium sp. (larvae) and Icthyouris sp. in Cyphocharax modestus; Contracaecum sp. (larvae), Cosmoxynemoides aguirrei and Pharyngodonidae gen. sp. in C. nagelii; Dioctophyma renale (larvae), Hysterothylacium sp. (larvae) and Rhabdochona sp. in Gymnotus sylvius; Capillariidae gen. sp. in Hoplosternum littorale; Cosmoxynema vianai, Guyanema sp., Ichthyouris sp. and Travnema travnema in Steindachnerina insculpta; Contracaecum sp. (larvae), Procamallanus (Spirocamallanus) rebecae (larvae) in Triportheus angulatus and Rhabdochona acuminata in Triportheus nematurus. This is first study of nematode parasites from the Peixe River, therefore all the species found are new geographical records and 19 are new host records. Se llevó a cabo un estudio de los nematodos parásitos de nueve especies de peces de agua dulce del Río do Peixe, Estado de São Paulo, Brasil. Los peces fueron colectados entre febrero de 2010 y marzo de 2011 y las especies encontradas fueron: Procamallanus (Spirocamallanus) inopinatus y Contracaecum sp. (larva) en Astyanax altiparanae; Contracaecum sp. (larva), Dioctophyma renale (larva), Philometroides caudata, P. (Spirocamallanus) inopinatus, P. (Spirocamallanus) neocaballeroi (larva) y P. (Spirocamallanus) saofranciscensis en Acestrorhynchus lacustris; Contracaecum sp. (larva), Guyanema sp., Hysterothylacium sp. (larva) y Icthyouris sp. en Cyphocharax modestus; Contracaecum sp. (larva), Cosmoxynemoides aguirrei y Pharyngodonidae. gen. sp. en C. nagelii; Dioctophyma renale (larva), Hysterothylacium sp. (larva) y Rhabdochona sp. en Gymnotus sylvius; Capillariidae gen. sp. en Hoplosternum littorale; Cosmoxynema vianai, Guyanema sp., Ichthyouris sp. y Travnema travnema en Steindachnerina insculpta; Contracaecum sp. (larva), Procamallanus (Spirocamallanus) rebecae (larva) en Triportheus angulatus y Rhabdochona acuminata en Triportheus nematurus. Este es el primer estudio de nemátodos parásitos de Río do Peixe, por lo tanto todas las especies son nuevos registros geográficos y 19 son nuevos registros de hospedadores.

We evaluated the fish composition and ecological attributes of the ichthyofauna collected in a limnological zone of the Taquaruçu Reservoir, lower Paranapanema River. Information about the fish community was updated when compared to the previous study (2006). Non-metric multidimensional scaling (NMDS) showed differences in species composition between periods and community weighted means (CWMs) exhibited changes in functional composition over time. Four functional indices were used in the principal coordinate analysis (PcoA) to measure changes in the functional space of species, whereas functional β-diversity inspected differences in the traits composition between the periods. 1,203 individuals were sampled of 43 species, being 16 non-native and 14 new records. Compared to 2006, 27 species were absent, most of them native to Loricariidae and Anostomidae, while Curimatidae and Pimelodidae decreased in abundance. Functional indexes showed a reduction in functional diversity, whereas new species records exhibited functional redundancy. It might have occurred a simplification of the fish community over time, excluding the migratory and specialists species such as the herbivores and detritivores. Accordingly, we concluded that the ichthyofauna of the Taquaruçu Reservoir might have been undergoing a process towards biotic homogenization. Resumo Avaliamos a composição de peixes e atributos ecológicos da ictiofauna coletada em uma zona limnológica do reservatório de Taquaruçu, baixo rio Paranapanema. As informações sobre a comunidade de peixes foram atualizadas quando comparadas ao estudo anterior (2006). O escalonamento multidimensional não métrico (NMDS) mostrou diferenças na composição de espécies entre os períodos, e as médias ponderadas da comunidade (CWMs) exibiram mudanças na composição funcional ao longo do tempo. Quatro índices funcionais foram utilizados na análise de coordenadas principais (PcoA) para medir as mudanças no espaço funcional das espécies, enquanto a β-diversidade funcional inspecionou diferenças na composição de traços entre os períodos. Foram amostrados 1,203 indivíduos de 43 espécies, sendo 16 não-nativas e 14 novos registros. Em comparação com 2006, 27 espécies estavam ausentes, a maioria nativa de Loricariidae e Anostomidae, enquanto Curimatidae e Pimelodidae diminuíram em abundância. Os índices funcionais mostraram redução na diversidade funcional, enquanto novos registros de espécies exibiram redundância funcional. Pode ter ocorrido uma simplificação da comunidade de peixes ao longo do tempo, excluindo as espécies migradoras e especialistas como os herbívoros e detritívoros. Dessa forma, concluímos que a ictiofauna do reservatório de Taquaruçu pode estar sofrendo um processo de homogeneização biótica.

Made available in DSpace on 2020-12-12T02:21:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01. Added 1 bitstream(s) on 2021-07-15T15:26:00Z : No. of bitstreams: 1 S1679-62252020000200209.pdf: 3377270 bytes, checksum: fb858d4e33c914b84d69d1175a701228 (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) A new species of Curimatopsis is described from the highlands of the western Guiana Shield in the río Carapo and río Paragua, tributaries of the río Caroni in the Orinoco basin, southeastern Venezuela. The new species belongs to the Curimatopsis macrolepis clade due to its possession of a long lower jaw that projects past the anterior margin of the upper jaw, and separate first and second hypurals. The new species is diagnosed from remaining species of the Curimatopsis macrolepis clade by having a small-sized inconspicuous dark spot on the midlateral surface of the caudal peduncle, by details of body and fin pigmentation, and by additional morphometric characters. The distribution of C. macrolepis in the Amazon and Orinoco basins is updated based on the examination of museum specimens. Laboratório de Biologia e Genética de Peixes Departamento de Biologia Estrutural e Funcional Instituto de Biociências Universidade Estadual Paulista IBB/UNESP, R. Prof. Dr. Antonio C. W. Zanin, 250 Laboratório de Biologia e Genética de Peixes Departamento de Biologia Estrutural e Funcional Instituto de Biociências Universidade Estadual Paulista IBB/UNESP, R. Prof. Dr. Antonio C. W. Zanin, 250 FAPESP: 14/26508-3 CNPq: 140193/2015-4 FAPESP: 16/11313-8 FAPESP: 18/24040-5

Made available in DSpace on 2020-12-12T01:53:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Potamorhina includes the largest species in the Neotropical fish family Curimatidae. They perform long-distance migrations in large schools and represent relative importance for regional fisheries in South American lowlands. A morphology-based phylogenetic study recognized five species and proposed interspecific phylogenetic relationships mostly based on osteology, squamation, and morphology of the gasbladder. Subsequent cytogenetic studies revealed extreme variability in diploid numbers and other cytomolecular structures and hypothesized multiple events of chromosome rearrangements with centric fissions followed by reversed fusions. However, neither the taxonomic revision and phylogeny nor the cytogenetic hypothesis of chromosome evolution in Potamorhina was tested using molecular phylogenetic approaches. Here, we use mitochondrial and nuclear DNA sequences to delimit species of Potamorhina with an extensive sampling across the Amazon basin and use phylogenetic methods to test prior hypothesis of multiple events of chromosome rearrangements during the evolution of the genus. Phylogenetic and species delimitation methods clearly support the presence of five species but reveal novel interspecific relationships allowing a reinterpretation of the morphological characters relative to the number of vertebrae, caudal peduncle pigmentation, and modifications in the gasbladder chambers. With the new phylogenetic arrangement, we propose a novel hypothesis of occurrence of a single chromosome fission in the lineage of P. latior followed by an extraordinary event that involved more than 20 chromosome-pair fissions during the evolution of the ancestor of P. altamazonica and P. squamoralevis. This novel hypothesis represents a simpler and more conceivable explanation for the achievement of these elevated chromosome numbers during the evolution of Potamorhina. Departamento de Morfologia Instituto de Biociências Universidade Estadual Paulista IBB/UNESP Departamento de Morfologia Instituto de Biociências Universidade Estadual Paulista IBB/UNESP

This study investigated the fauna of monogeneans on gills of 13 fish species from the Matapi River, Brazilian Amazon. A total 548 fish belonging to 13 species (1 Anostomidae, 3 Characidae, 1 Curimatidae, 1 Hemiodontidae, 2 Serrasalmidae, 3 Scianidae, 1 Ageneiosidae and 1 Tetradontidae) were examined. From these fish, 6 species were infected and with a total prevalence of 22.4%. Monogeneans collected are represented by the following taxa: Anacanthorus gravihamulatus, Notozothecium minor, Notozothecium penetrarum, Diplectanum piscinarius, Aetheolabes goeldiensis, Euryhaliotrema succedanus, Anacanthorus jegui, Urocleidoides astyanacis, Urocleidoides strombicirrus, Euryhaliotrema sp. and Urocleidoides spp. There was a variation in the prevalence, mean intensity and mean abundance of monogeneans among the host populations examined. Monogeneans of Metynnis lippincottianus, Plagioscion squamosissimus, Astyanax bimaculatus and Curimata incompta presented a highly aggregated dispersion pattern. Body weight of M. lippincottianus and C. incompta presented a weak positive correlation with abundance of parasites. Lastly, this is first study for 12 fish species from the Matapi River and the first report of E. succedanus for Plagioscion surinamensis and N. penetrarum for Serrasalmus rhombeus. Resumo Este estudo investigou a fauna de monogeneas das brânquias de 13 espécies de peixes do Rio Matapi, na Amazônia brasileira. Foram examinados um total de 548 peixes pertencentes a 13 espécies (1 Anostomidae, 3 Characidae, 1 Curimatidae, 1 Hemiodontidae, 2 Serrasalmidae, 3 Scianidae, 1 Ageneiosidae e 1 Tetradontidae). Entre esses peixes, 6 espécies estavam infectadas e houve uma prevalência total de 22,4%. As espécies de monogeneas coletadas foram distribuídas nos seguintes táxons: Anacanthorus gravihamulatus, Notozothecium minor, Notozothecium penetrarum Diplectanum piscinarius, Euryhaliotrema sp., Aetheolabes goeldiensis, Euryhaliotrema succedanus, Anacanthorus jegui, Urocleidoides astyanacis, Urocleidoides strombicirrus Urocleidoides spp. Houve variação na prevalência, intensidade média e abundância média de monogeneas entre as populações hospedeiras. Monogeneas em Metynnis lippincottianus, Plagioscion squamosissimus, Astyanax bimaculatus e Curimata incompta apresentaram um padrão de dispersão altamente agregado. O peso corporal de M. lippincottianus do Rio Matapi mostrou uma correlação positiva fraca com a abundância de A. jegui. O comprimento de C. incompta também mostrou uma correlação positiva fraca com abundância de Urocleidoides spp. Por fim, este é primeiro estudo para 12 espécies de peixes da bacia do Rio Matapi e registra pela primeira vez E. succedanus para Plagioscion surinamensis e N. penetrarum para Serrasalmus rhombeus.

A new species of Cyphocharax is described from the rio Mentaí, a tributary of rio Arapiuns, lower rio Tapajós basin, Pará state, Brazil. The new species can be distinguished from its congeners by the combination of a rounded dark blotch at the caudal peduncle and a pattern of horizontal stripes formed by series of conspicuous dark spots situated over the center of the scales on the lateral and dorsolateral surfaces of the body. The new Cyphocharax is compared with similar congeners as C. helleri, C. multilineatus, and C. pantostictos. Comments on the distribution of C. multilineatus are provided. RESUMO Uma nova espécie de Cyphocharax é descrita do rio Mentaí, um tributário do rio Arapiuns, bacia do baixo rio Tapajós, estado do Pará, Brasil. A nova espécie se diferencia de todos os congêneres por possuir uma mancha preta arredondada no pedúnculo caudal e um padrão de listras horizontais formadas por manchas escuras conspícuas situadas no centro das escamas laterais e dorsolaterais. O novo Cyphocharax é comparado com os congêneres mais similares como C. helleri, C. multilineatus e C. pantostictos. Comentários sobre a distribuição de C. multilineatus são fornecidos.

Made available in DSpace on 2019-10-04T12:30:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-10-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) NSF Curimatidae, the fourth largest family of detritivorous Neotropical characiform fishes, encompasses eight extant genera and over 110 species dwelling in diverse freshwater habitats from Costa Rica to Argentina. Extensive phylogenetic analyses of soft anatomy and osteology provided evidence for intergeneric and most interspecific relationships, and formed the basis of curimatid taxonomy for nearly 40 years. However, that morphological phylogeny demonstrated incomplete phylogenetic resolution at various scales and has never been tested with extensive molecular data. Herein, we infer molecular phylogenies spanning similar to 70% of the known species diversity using three nuclear and three mitochondrial loci. Topologies from concatenated likelihood and Bayesian analyses and coalescent Bayesian species trees agree broadly with each other, and with the prior morphological hypothesis in many, but not all respects. All molecular analyses support the monophyly of Curimatidae and of six of its constituent genera, and agree on the placement of Curimatopsis as sister to all other curimatids. DNA-based intergeneric relationships differ substantially from prior morphological hypotheses by placing Curimata sister to Potamorhina and Psectrogaster sister to Pseudocurimata, rather than in a ladderized arrangement. Our results also resolve a major uncertainty in the morphological tree by revealing Cyphocharax, a genus for which no anatomical synapomorphy has ever been proposed, as a paraphyletic assemblage containing a monophyletic Steindachnerina and a polyphyletic Curimatella. Overall, the phylogeny expands substantially our understanding of the morphology, phylogenetics and evolution of the Curimatidae, and will guide future intrageneric studies by improving precision in the choice of comparative taxa. Univ Estadual Paulista, Inst Biociencias, Dept Morfol, Botucatu, SP, Brazil Smithsonian Inst, Dept Vertebrate Zool, Natl Museum Nat Hist, Washington, DC 20560 USA Oregon State Univ, Dept Fisheries & Wildlife, Corvallis, OR 97331 USA Cornell Univ, Museum Vertebrates, Dept Ecol & Evolutionary Biol, Ithaca, NY USA Univ Estadual Paulista, Inst Biociencias, Dept Morfol, Botucatu, SP, Brazil FAPESP: 2011/08374-1 FAPESP: 2013/16436-2 FAPESP: 2014/26508-3 FAPESP: 2016/11313-8 NSF: DEB-1257898

espanolResumen Con el objetivo de reproducir vizcaina Curimata mivartii, ejemplares de dos anos de edad (n= 54), mantenidos en estanques en tierra (0,1 pez/m2) fueron inducidos con extracto pituitario de carpa (EPC) (Argent, USA) a razon de 6 mg/Kg de peso para las hembras en dos aplicaciones (10 % y 90% con 12 horas entre aplicacion); mientras que los machos fueron inducidos con 4,8 mg/Kg EPC en dosis unica. Antes de la induccion hormonal a cada hembra le fue realizada biopsia para verificar su estado de maduracion gonadal. La muestra de ovocitos fue tratada con solucion Serra (Chemi, Colombia) y despues de tres minutos, con la ayuda de un estereoscopio de luz, (Leica, EZ4 W, Alemania) en objetivo de 4x, se determino posicion de la vesicula germinal (centrico, migrando, periferico, sin nucleo). El analisis de la biopsia ovarica mostro que las hembras se encontraban en maduracion final. Los machos inducidos se encontraron en fase de espermiacion; los cuales a ligera presion abdominal liberaron liquido seminal. Se estimo el indice de ovulacion, fecundidad (absoluta y relativa), diametro de los ovocitos y volumen seminal. El porcentaje de fertilidad fue estimado a las cuatro horas post-eclosion (hpe) y el porcentaje de eclosion fue estimado a las 10 hpe. Las hembras ovularon entre 5 y 6 horas (28±1,0°C) e inmediatamente los huevos fueron obtenidos por extrusion, asi como el semen. La fecundidad absoluta fue de 178331,6±28773,7 ovocitos/hembra y la relativa 137,7±19,6 g ovocitos/Kg de hembra. El diametro de los ovocitos recien desovados fue de 687,2±42,8 µm. La fertilidad fue de 90,7±1,4% y la eclosion de 85,3±1,5%. Los resultados permiten concluir que EPC a dosificacion de 6mg/Kg de peso es un buen inductor de la reproduccion de vizcaina, con alto indice de ovulacion y altos porcentajes de fertilidad y eclosion. EnglishAbstract With the aim of reproducing the vizcaina Curimata mivartii, two-year-old specimens (n = 54), kept in ponds on land (0,1 fish/m2) were induced with carp pituitary extract (EPC) (Argent, USA) at a doses of 6 mg/Kg of weight for females in two applications (10% and 90% with 12 hours between applications), while males were induced with 4,8 mg / Kg EPC in a single dose. Before the hormonal induction, each female underwent an ovarian biopsy to verify the oocytes maturation stage. The oocyte sample was treated with Serra solution (Chemi, Colombia) and after three minutes, with the help of a light stereoscope (Leica, EZ4 W, Germany) in 4x objective, the position of the germinal vesicle was determined (central, migrating, peripheral, breakdown). The analysis of the ovarian biopsy showed that the females were in final maturation. Induced males were found in the spermiation phase; which at light abdominal pressure released seminal fluid. The ovulation index, fecundity (absolute and relative), oocyte diameter and seminal volume were estimated. The percentage of fertility was estimated at four hours after hatching (hah); and the hatching percentage was estimated at 10 hah. The females ovulated between 5 and 6 hours (28±1,0°C) and immediately the eggs were obtained by extrusion, as well as the semen. The absolute fecundity was 178331,6±28773,7 oocytes/female and the relative 137,7±19,6 g oocytes/Kg of female. The diameter of the newly spawned oocytes was 687,2±42,8 µm. Fertility was 90,7±1,4% and hatching 85,3±1,5%. The results allow to conclude that EPC at dosage of 6mg/Kg of weight is a good inducer of the vizcaina reproduction, which high ovulation index and high rates of fertility and hatching. portuguesResumo Com o objetivo de reproduzir vizcaina Curimata mivartii, especimenes de dois anos de idade (n = 54), mantidos em tanques em terra (0,1 peixes / m2) foram induzidos com extrato de hipofise de carpa (EPC) (Argent, USA) a uma taxa de 6 mg / kg de peso para as femeas em duas aplicacoes (10% e 90% com 12 horas entre aplicacoes), enquanto os machos foram induzidos com 4,8 mg / kg de EPC em dose unica. Antes da inducao hormonal para cada femea, uma biopsia ovariana foi realizada para verificar o seu estado de maturacao gonadal. A amostra de oocitos foi tratada com solucao de Serra (Chemi, Colombia) e apos tres minutos, com auxilio de um estereoscopio de luz (Leica, EZ4 W, Alemanha) em objetivo 4x, foi determinada a posicao da vesicula germinativa (central, migrando, periferico, sem nucleo). A analise da biopsia ovariana mostrou que as femeas estavam em maturacao final. Os machos induzidos foram encontrados na fase de espermizaҫa; que na pressao abdominal leve liberou fluido seminal. O indice de ovulacao, fecundidade (absoluta e relativa), diâmetro do oocito e volume seminal foram estimados. A percentagem de fertilidade foi estimada em quatro horas pos-eclosao (hpe); enquanto a porcentagem de eclosao foi estimada em 10 hp. As femeas ovularam entre 5 e 6 horas (28±1,0°C) e imediatamente os ovos foram obtidos por extrusao, assim como o semen. A fecundidade absoluta foi 178331,6±28773,7 oocitos / femea e a relativa 137,7±19,6 g oocitos / kg de femea. O diâmetro dos oocitos recem-gerados foi 687,2±42,8 µm. A fertilidade foi de 90,7±1,4% e incubacao de 85,3±1,5%. Os resultados permitem concluir que a EPC na dosagem de 6mg/Kg de peso e um bom indutor de reproducao de vizcaina, com alto indice de ovulacao e altas taxas de fertilidade e eclosao.

A new species of Cyphocharax (Characiformes: Curimatidae) is described from the lower Rio Tapajos basin, including its tributary, the Rio Arapiuns, Para, Brazil. The new species is diagnosed from congeners by a combination of characters that includes overall body light-colored, with a silvery hue, lacking any pattern of stripes or blotches, a distinctly straight body profile, and some meristic and morphometric features. Comparisons with similar congeners as Cyphocharax festivus, Cyphocharax leucostictus, Cyphocharax nigripinnis, and Cyphocharax plumbeus, some of which occur sympatrically with the new species, are presented.

The Lower Anapu River, Eastern Amazon, has a discrete flood pulse with narrow flooded areas due to the reduced influence of tides. In this environment, local precipitation might act as an important factor in the input of detritus, which can serve as a trigger for fish reproductive period. Therefore, this paper aims to determine the effects of local precipitation on the reproductive ecology of an abundant detritivorous fish in flooded rivers. Between May 2012 and April 2013, 886 specimens (471 females and 415 males) were captured monthly using gill nets. Individuals were measured, weighted, sexed, and the gonadal development stage was defined macroscopically and confirmed histologically. Sex ratio, length-weight relationship (LWR), condition factor (k), Gonadosomatic Index (GSI), relative frequency of maturity stages, and size at first gonadal maturity (L50) were estimated and tested in relation to rainfall periods. There was no difference between the expected sex ratio (1:1), and both males and females showed polyphasic growth. The condition factor indicated higher values at the beginning of the rainy season and lower values during the dry season for both sexes. GSI and relative frequency of mature individuals indicated a long reproduction period with gonadal investment starting within the dry season until early in the rainy season for spawning within the rains. The L50 value showed that males reach sexual maturity before females. Results indicated a reproductive pattern strongly influenced by rainfall, corroborating the importance of local precipitation for lacustrine environments.