Cytogenetic characterization in Hoplias brasiliensis (Characiformes, Erythrinidae) from an isolated river basin in northeastern South America Leonardo dos Santos Gonçalves Ferreira, Jamille de Araújo Bitencourt, André Teixeira da Silva, Paulo Roberto Antunes de Mello Affonso Cytologia, 2025 The genus Hoplias (trahiras) represents a species-rich group of controversial taxonomy in the family Erythrinidae. Even though cytogenetic analyses have been useful to discriminate cryptic fish species, most chromosomal data in Erythrinidae are focused on Hoplias malabaricus (common trahira), considered a species complex based on the presence of reproductively isolated karyomorphs. In turn, the giant trahiras (Hoplias gr. lacerdae and H. aimara complexes) seem to be more cytogenetically conserved even though there are few karyotypic reports in this group. In order to increase the chromosomal information in the giant trahiras, we provided the first cytogenetic characterization in a population of H. brasiliensis from an isolated river basin in Northeastern Brazil. We confirmed the general karyotype trend observed in this fish group, i.e., a diploid number (2n) of 50 distributed into 20 metacentric (m) and 30 submetacentric (sm) chromosomes, pericentromeric heterochromatin segments and active nucleolar organizer regions (Ag-NORs) at interstitial region on long arms of a sm pair. On the other hand, heteromorphic GC-rich (CMA3+) sites were observed at the pericentromeric region of up to 10 chromosomal pairs in H. brasiliensis, diverging from the usual pattern reported in other populations and species of giant trahiras. The present findings indicate that, in spite of the apparent chromosomal conservativeness in this fish group, some genomic regions have undergone distinct evolutionary pathways, even within a same nominal taxon. Therefore, the utilization of refined analyses of chromosomal microstructure is recommended as a powerful tool to resolve the taxonomic uncertainties in giant trahiras.
Hierarchical Modelling Reveals Local Environmental Metrics as Key Predictors of Fish Stream Assemblage Structure Fabiane Barreto Souza, Alexandre Clistenes Alcântara Santos, André Teixeira da Silva, Nuno Caiola Ecology of Freshwater Fish, 2025 Environmental factors act at multiple spatial scales, shaping the fish assemblage structure in streams. Understanding catchment‐stream relationships through hierarchical classification can aid in the conservation and management of freshwater ecosystems. The main goal of our work was to use the Hierarchical Modelling of Species Communities framework to answer the following questions: Which environmental variables are more important in structuring stream assemblages? Do ecomorphological traits influence species' responses to environmental conditions? What is the pattern of species co‐occurrences along the streams? We fitted models with two alternative response datasets: a community matrix (site × species) with presence/absence data (PA) and abundance data (ABU). Species ecomorphological traits were also included in the models. We tested models considering the environmental variables at each scale separately (local and catchment) and considering all variables together. Variables at the local scale explained 57.1% (PA) and 53.3% (ABU) of the overall variance portion partitioning, while catchment variables explained only 36.6% and 23.3%, respectively. Traits explained only 47.9% (PA) and 18.93% (ABU) of the variation. No significant correlation between species co‐occurrences was found. Our results suggest that local‐scale metrics better predict the structure of fish assemblages in headwater streams from the Chapada Diamantina region of Caatinga.
Small Fishes, Big Issues: Species Delimitation in Hemigrammus Marginatus, Gill, 1958 (Acestrorhamphidae: Pristellinae) from Brazilian Coastal Basins Based on Integrative Genetics Mauricio B. Fernandes, Jamille de Araújo Bitencourt, André Teixeira da Silva, Marcelo Ricardo Vicari, Matheus Azambuja, Paulo Roberto Antunes de Mello Affonso Zebrafish, 2025 The small characins represent a systematic puzzle in the Neotropical ichthyofauna as a result of independent miniaturization processes, adaptive convergence and lack of diagnostic characters for several genera. In order to diminish the taxonomic uncertainties and the evolutionary pathways in Hemigrammus , we carried out an integrative genetic analysis in the putatively widespread Hemigrammus marginatus Ellis, 1958 by combining cytogenetic and molecular data based on the mitochondrial Cytochrome C Oxidase subunit I (COI). Specimens of H. marginatus from the type locality in Itapicuru River basin and other two populations from coastal rivers in northeastern Brazil were analyzed and compared with the available data from other regions in South America. Conspicuous macro and microkaryotypic differences were detected between the samples from northeastern and southern Brazil (Upper Paraná River basin). Likewise, the DNA barcoding and species delimitation analyses recovered distinct Molecular Operational Taxonomical Units within H. marginatus . Therefore, the population from the type locality should be referred to as H. marginatus stricto sensu , representing a restricted characin taxon from coastal drainages (including the São Francisco River basin) along northeastern Brazil, while other populations of this small characin fish need to be taxonomically revised and managed as unique lineages.
Trophic plasticity of tetra-fish, Psalidodon aff. fasciatus (Cuvier, 1819) (Characidae), in an Atlantic Forest stream of Northeast Brazil INGRID CAROLINE C. PIRES, FABIANE B. SOUZA, ANDRÉ T. DA SILVA Anais Da Academia Brasileira De Ciencias, 2024 Trophic plasticity is a distinctive feature of freshwater fishes, representing an essential strategy for fish living in resource-variable environments. We analyzed the stomach contents of individuals sampled in two Atlantic Forest streams to identify the primary food sources consumed by Psalidodon aff. fasciatus and verify the existence of spatial, seasonal, and ontogenetic variations. The diet was determined by analyzing the stomach contents using the Volume Method to quantify the importance of food items. In general, Psalidodon aff. fasciatus was classified as an omnivorous species, consuming mainly insects, plant material, and filamentous algae. The results also showed significant effects for all factors considered (spatial, seasonal, and ontogenetic). Finally, Psalidodon aff. fasciatus demonstrated considerable trophic plasticity, which can result in better use of available resources in the environment and improved resource partitioning, reducing intraspecific and interspecific competition.
“Split Happens”: a Rare Case of Chromosomal Mosaicism in Characin from an Impacted River Basin Mauricio Barros Fernandes, Jamille de Araújo Bitencourt, José Henrique Galdino, André Teixeira da Silva, Paulo Roberto Antunes de Mello Affonso Brazilian Archives of Biology and Technology, 2024 Abstract Chromosomal polymorphisms have been reported in numerous vertebrates, including fishes. Such variation is usually related to karyoevolutionary trends and speciation but might also be a result of environmental stress. Herein, we provide the first karyotype characterization in populations of a widespread small characin (Hemigrammus marginatus) from an impacted river basin in Northeastern Brazil to infer their chromosome organization and putative genotoxic effects. Therefore, we reported intra and interindividual structural polymorphism and multiple active nucleolar organizer regions in samples from Contas River, a highly polluted environment when compared to less impacted areas. Furthermore, this report represents the first description of chromosomal mosaicism in the family Characidae so far. Besides revealing peculiar karyotypic patterns in relation to populations from other basins, our results suggest that the chromosomal instability in specimens H. marginatus might be associated with the presence of xenobiotics in polluted environments.
NEOTROPICAL FRESHWATER FISHES: A dataset of occurrence and abundance of freshwater fishes in the Neotropics Lívia Helena Tonella, Renata Ruaro, Vanessa Salete Daga, Diego Azevedo Zoccal Garcia, Oscar Barroso Vitorino, Tatiana Lobato‐de Magalhães, Roberto Esser dos Reis, Fabio Di Dario, Ana Cristina Petry, Michael Maia Mincarone, Luciano Fogaça de Assis Montag, Paulo Santos Pompeu, Adonias Aphoena Martins Teixeira, Alberto Luciano Carmassi, Alberto J. Sánchez, Alejandro Giraldo Pérez, Alessandra Bono, Aléssio Datovo, Alexander S. Flecker, Alexandra Sanches, Alexandre Lima Godinho, Alexandre Matthiensen, Alexandre Peressin, Alexandre Wagner Silva Hilsdorf, Alexéia Barufatti, Alice Hirschmann, Aline Jung, Allan K. Cruz‐Ramírez, Alline Braga Silva, Almir Manoel Cunico, Amanda Saldanha Barbosa, Amauri de Castro Barradas, Ana Carolina Lacerda Rêgo, Ana Clara Sampaio Franco, Ana Paula Lula Costa, Ana Paula Vidotto‐Magnoni, Anderson Ferreira, Anderson Kassner Filho, André Batista Nobile, André Lincoln Barroso Magalhães, André Teixeira da Silva, Andréa Bialetzki, Andréa Cristina dos Santos Maroclo Gomes, Andrezza Bellotto Nobre, Armando Cesar Rodrigues Casimiro, Arturo Angulo Sibaja, Arthur Alexandre Capelli dos Santos, Átila Rodrigues de Araújo, Augusto Frota, Bárbara Angélio Quirino, Beatriz Moreira Ferreira, Bianca Weiss Albuquerque, Bruna Arbo Meneses, Brunno Tolentino Oliveira, Bruno Augusto Torres Parahyba Campos, Bruno Bastos Gonçalves, Bruno Busnello Kubiak, Bruno da Silveira Prudente, Bruno Gorini de Araujo Passos Pacheco, Bruno Kazuo Nakagawa, Bruno Tayar Marinho do Nascimento, Calebe Maia, Camila Cantagallo Devids, Carla Ferreira Rezende, Carla Muñoz‐Mendoza, Carlos A. Peres, Carlos Alberto de Sousa Rodrigues Filho, Carlos Alberto Santos de Lucena, Carlos Alexandre Fernandes, Carlos Benhur Kasper, Carlos Donascimiento, Carmino Emidio, Carolina Carrillo‐Moreno, Carolina Machado, Carolina Pera, Caroline Hartmann, Catherine M. Pringle, Cecília Gontijo Leal, Céline Jézéquel, Chris Harrod, Clarissa Alves da Rosa, Claudio Quezada‐Romegialli, Crisla Maciel Pott, Crislei Larentis, Cristiane A. S. Nascimento, Cristina da Silva Gonçalves, Cristina Jaques da Cunha, Cristina Moreira Pisicchio, Daniel Cardoso de Carvalho, Daniel Galiano, Daniel Gomez‐Uchida, Daniel Oliveira Santana, Daniel Salas Johnson, Danielle Katharine Petsch, Danielly Torres Hashiguti de Freitas, Dayani Bailly, Débora Ferreira Machado, Débora Reis de Carvalho, Dhyego Hamilton Topan, Diego Cañas‐Rojas, Diego da Silva, Diogo Freitas‐Souza, Dilermando Pereira Lima‐Júnior, Diovani Piscor, Djalma Pereira Moraes, Douglas Viana, Dyego Leonardo Ferraz Caetano, Éder André Gubiani, Edson K. Okada, Eduardo Cazuni do Amaral, Eduardo Meneguzzi Brambilla, Eduardo Ribeiro Cunha, Elaine Antoniassi Luiz Kashiwaqui, Elise Amador Rocha, Elisete Ana Barp, Elmary da Costa Fraga, Elvira D'Bastiani, Eugenia Zandonà, Eurizângela Pereira Dary, Evanilde Benedito, Everardo Barba‐Macías, Evelyn Vanessa Calvache Uvidia, Fabiana Luques Fonseca, Fabiane Silva Ferreira, Fábio Lima, Fábio Maffei, Fábio Porto‐Foresti, Fabrício Barreto Teresa, Fabrício de Andrade Frehse, Fagner Júnior M. Oliveira, Felipe Pessoa da Silva, Felipe Pontieri de Lima, Fernanda Dotti do Prado, Fernando Camargo Jerep, Fernando Emmanuel Gonçalves Vieira, Fernando Gertum Becker, Fernando Rogério de Carvalho, Flávio Kulaif Ubaid, Francisco Keilo Teixeira, Francisco Provenzano Rizzi, Francisco Severo‐Neto, Francisco Villamarín, Franco Teixeira de Mello, Friedrich Wolfgang Keppeler, Gabriel de Avila Batista, Gabriel de Menezes Yazbeck, Giancarlo Tesitore, Gilberto Nepomuceno Salvador, Gita Juan Soteroruda Brito, Giulianna Rondineli Carmassi, Gregório Kurchevski, Guillermo Goyenola, Hasley Rodrigo Pereira, Helen Jamille Fernandes Silva Alvez, Helena Alves do Prado, Henrique Ledo Lopes Pinho, Híngara Leão Sousa, Hugo Bornatowski, Hugo de Oliveira Barbosa, Ibon Tobes, Igor de Paiva Affonso, Igor Raposo Queiroz, Irma Vila, Iván Vinicio Jácome Negrete, Ivo Gavião Prado, Jean Ricardo Simões Vitule, Jessé Figueiredo‐Filho, Jessica Antúnez Gonzalez, Jéssica Caroline de Faria Falcão, Jéssica Vieira Teixeira, Jimmy Pincheira‐Ulbrich, Jislaine Cristina da Silva, João Antonio de Araujo Filho, João Fernando Marques da Silva, João Gabriel Genova, João Gabriel Ribeiro Giovanelli, João Vitor Perin Andriola, Jonatas Alves, Jonathan Valdiviezo‐Rivera, Jorge Brito, Jorge Iván Sánchez Botero, Jorge Liotta, Jorge Luis Ramirez, Jorge Reppold Marinho, José Luís Olivan Birindelli, Jose Luis Costa Novaes, Joseph E. Hawes, Josiane Ribolli, Juan Francisco Rivadeneira, Juan Jacobo Schmitter‐Soto, Juliana Camara Assis, Juliana Paulo da Silva, Juliana Silveira dos Santos, Juliana Wingert, Juliana Wojciechowski, Juliano André Bogoni, Juliano Ferrer, Julio César Jut Solórzano, Júlio César Sá‐Oliveira, Jussara Oliveira Vaini, Kamila Contreras Palma, Karine Orlandi Bonato, Karla Dayane de Lima Pereira, Kassiano dos Santos Sousa, Kevin Giancarlo Borja‐Acosta, Laís Carneiro, Larissa Faria, Leonardo Brito de Oliveira, Leonardo Cardoso Resende, Leonardo Ferreira da Silva Ingenito, Leonardo Oliveira Silva, Leydiane Nunes Rodrigues, Lida Guarderas‐Flores, Lidiane Martins, Lorena Tonini, Lorrana Thaís Máximo Durville Braga, Louise Cristina Gomes, Lucas de Fries, Lucas Gonçalves da Silva, Lucas Ribeiro Jarduli, Luciano Benedito Lima, Luciano Gomes Fischer, Luciano Lazzarini Wolff, Luciano Neves dos Santos, Luis Artur Valões Bezerra, Luisa Maria Sarmento Soares, Luisa Resende Manna, Luiz Fernando Duboc, Luiz Guilherme dos Santos Ribas, Luiz Roberto Malabarba, Marcelo Fulgêncio Guedes Brito, Marcelo Rennó Braga, Marcelo Silva de Almeida, Maria Cecília Sily, Maria Claudene Barros, Maria Histelle Sousa do Nascimento, Maria Laura de Souza Delapieve, Maria Teresa Fernandez Piedade, Marina Tagliaferro, Mário Cesar Cardoso de Pinna, Mario H. Yánez‐Muñoz, Mário Luís Orsi, Marlon Ferraz da Rosa, Marlos Bastiani, Marta Severino Stefani, Martha Buenaño‐Carriel, Martha Elena Valdez Moreno, Mateus Moreira de Carvalho, Mateus Tavares Kütter, Matheus Oliveira Freitas, Mauricio Cañas‐Merino, Mauricio Cetra, Mauricio Herrera‐Madrid, Mauricio Mello Petrucio, Mauro Galetti, Miguel Ángel Salcedo, Miguel Pascual, Milton Cezar Ribeiro, Milza Celi Fedatto Abelha, Mônica Andrade da Silva, Mônica Pacheco de Araujo, Murilo Sversut Dias, Naiara Guimaraes Sales, Naraiana Loureiro Benone, Natane Sartor, Nelson Ferreira Fontoura, Nicholas Silvestre de Souza Trigueiro, Nicolás Álvarez‐Pliego, Oscar Akio Shibatta, Pablo A. Tedesco, Pablo Cesar Lehmann Albornoz, Pablo Henrique Fernandes Santos, Pâmela Virgolino Freitas, Patricia Calegari Fagundes, Patrícia Domingues de Freitas, Patricio Mena‐Valenzuela, Paul Tufiño, Paula Araujo Catelani, Paula Peixoto, Paulo Ilha, Pedro De Podestà Uchôa de Aquino, Pedro Gerhard, Pedro Hollanda Carvalho, Pedro Jiménez‐Prado, Pedro Manoel Galetti, Pedro Paulino Borges, Pedro Peixoto Nitschke, Pedro Sartori Manoel, Phamela Bernardes Perônico, Philip Teles Soares, Pitágoras Augusto Piana, Priscila de Oliveira Cunha, Priscila Plesley, Rafael Couto Rosa de Souza, Rafael Rogério Rosa, Rana W. El‐Sabaawi, Raoni Rosa Rodrigues, Raphael Covain, Raquel Coelho Loures, Raul Rennó Braga, Reginaldo Ré, Rémy Bigorne, Renata Cassemiro Biagioni, Renato Azevedo Matias Silvano, Renato Bolson Dala‐Corte, Renato Tavares Martins, Ricardo Rosa, Ricardo Sartorello, Rodrigo de Almeida Nobre, Ronald D. Bassar, Ronaldo César Gurgel‐Lourenço, Ronaldo Fernando Martins Pinheiro, Ronaldo Leal Carneiro, Rosa Florido, Rosana Mazzoni, Rosane Silva‐Santos, Rosiane de Paula Santos, Rosilene Luciana Delariva, Sandra Maria Hartz, Sebastien Brosse, Sérgio Luiz Althoff, Shaka Nóbrega Marinho Furtado, Sidnei Eduardo Lima‐Junior, Silvia Yasmin Lustosa Costa, Solange Arrolho, Sonya K. Auer, Sybelle Bellay, Taís de Fátima Ramos Guimarães, Talitha Mayumi Francisco, Tatiane Mantovano, Tatyana Gomes, Telton Pedro Anselmo Ramos, Thaís de Assis Volpi, Thais Moura Emiliano, Thiago Augusto Pedroso Barbosa, Thiago José Balbi, Thiago Nascimento da Silva Campos, Thiago Teixeira Silva, Thiago Vinícius Trento Occhi, Thiely Oliveira Garcia, Tiago Magalhães da Silva Freitas, Tiago Octavio Begot, Tony Leandro Rezende da Silveira, Ueslei Lopes, Uwe Horst Schulz, Valéria Fagundes, Valéria Flávia Batista da Silva, Valter M. Azevedo‐Santos, Vanessa Ribeiro, Vanessa Graciele Tibúrcio, Vera Lúcia Lescano de Almeida, Victoria J. Isaac‐Nahum, Vinicius Abilhoa, Vinicius Farias Campos, Vinicius Tavares Kütter, Vivian de Mello Cionek, Viviane Prodocimo, Wagner Vicentin, Waldney Pereira Martins, Walna Micaelle de Moraes Pires, Weferson Júnio da Graça, Welber Senteio Smith, Wesley Dáttilo, Windsor Efren Aguirre Maldonado, Yuri Gomes Ponce de Carvalho Rocha, Yzel Rondon Súarez, Zilda Margarete Seixas de Lucena Ecology, 2023 The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large‐scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications.
Trophic structure of ichthyofauna in streams of the Contas River basin, Brazil Fabiane Barreto Souza, Alexandre Clistenes de Alcantara Santos, André Teixeira da Silva Studies on Neotropical Fauna and Environment, 2022 Understand how environmental factors correlate with the trophic structure of fish communities is a fundamental step to allow designing models for the functioning of stream ecosystems and planning conservation actions. Thus, this study aims to characterize the trophic structure of fish communities of streams of the Contas River basin and evaluate the relationships between local environmental factors (stream structure and limnological variables) and trophic structure. We sample nine streams of the Upper Contas sub-basin and nine of the Gongogi sub-basin using electric fishing. We analyzed the diet of 24 species, arranged in six trophic guilds, according to stomach contents: detritivores, omnivores, insectivores, invertivores, piscivores, and algivores. The results show high proportions of detritivores (46.62%), omnivores (28.55%), and insectivores (11.8%). Invertivores were correlated to colder streams, and with little proportion of sand in the substrate. Algivores were positively related to temperature and proportion of sand in the substrate. The relationship between other guilds and the environmental factors was not significant, probably due to limitations in the number of streams in the analysis. The sub-basins did not differ regarding the trophic structure, corroborating the perception that the trophic structure is more influenced by local factors than by broader scale factors.
Length–weight relationship for ten native fish species captured in the streams of the Contas River basin, Northeastern Mata Atlântica freshwater ecoregion, Brazil André Silva, Roberto Goitein, Fabiane Souza, Manuela Martins, Ricardo Jucá‐Chagas, Fabio Cop Ferreira Journal of Applied Ichthyology, 2021 This work describes the length-weight relationship (LWR) of ten fish species from the Contas River Basin, Bahia State, Brazil. Sampling was conducted quarterly between November 2012 and November 2013 in 18 wadeable streams (nine in the Diamantina Plateau, Caatinga biome, and nine in the Atlantic forest biome). The fishes were caught using electrofishing (800V DC) and hand nets (2.0 mm mesh size) in 50 meters stretch by the sample unit. Collected fishes were fixed in formalin and preserved in alcohol, and thus some shrinking probably occurred. The values of parameter b of the LWR (W = aLb) ranged between 2.763 and 3.267. It is the first record of LWR parameters for nine species, all endemic to Northeastern Mata Atlântica freshwater ecoregion (NMAF). Moreover, new maximum lengths are presented for five species.
Diet of a bromeligenous species of treefrog in the Brazilian semiarid Silvana Souza de Oliveira, André Teixeira da Silva, Juliana Zina Brazilian Journal of Biology, 2021 Phyllodytes tuberculosus is a bromeligenous anuran species whose geographic distribution is restricted to areas of the Caatinga and to transition zones between Caatinga and Atlantic Forest in the central-south of the state of Bahia. Its existence in close relationship with bromeliads and its occurrence in dry and highly seasonal environments drove us to the supposition that species is opportunistic/generalist regard to diet. We collected the items present in the stomach of 43 P. tuberculosus individuals with stomach-flushing method. Of these, 18 stomach contents were obtained during the dry period (April–October), and 25 during the rainy period (November–March). We recorded nine classes of prey, finding the greatest relative importance for the categories Formicidae and Coleoptera in dry season and Blattodea (Termites), Formicidae and Coleoptera in the rainy season. Phyllodytes tuberculosus presented a varied, possibly opportunistic diet in semiarid environments. Additionally, we report an apparent temporal differentiation related to the typical Caatinga seasonality. This study adds to the data on the natural history of an anuran species adapted to a semiarid environment with a narrow geographic distribution.
Freshwater fishes of the Bahia State, Northeastern Brazil André Teixeira Silva, Ricardo Jucá Chagas, Alexandre Clistenes de Alcântara Santos, Angela Maria Zanata, Beatriz Kawamura Rodrigues, Carla Natacha Marcolino Polaz, Carlos Bernardo Mascarenhas Alves, Cristiana Souza Vieira, Fabiane Barreto Souza, Fábio Vieira, Francisco Alexandre Costa Sampaio, Harildon Ferreira, Hilda Susele Rodrigues Alves, Luisa Maria Sarmento-Soares, Marianna Pinho, Ronaldo Fernando Martins-Pinheiro, Sergio Maia Queiroz Lima, Sofia Campiolo, Priscila Camelier Biota Neotropica, 2020
