Consulta: subjectFacets:"Neotropical fishes"
Registros recuperados: 24
Data/hora: 10/06/2024 03:33:00

Allozyme differentiation of two populations of the genus Neoplecostomus Eigenmann &amp;amp; Eigenmann, 1888 (Teleostei, Loricariidae) from the upper Paraná River basin, Brazil
Provedor de dados: 74
Autores: Reusing,Ana Flávia; Renesto,Erasmo; Roxo,Fábio F.; Zawadzki,Cláudio H.
Allozyme electrophoresis was used to examine 12 enzymatic systems in two populations of the genus Neoplecostomus from the Paraná River basin. Samples of Neoplecostomus sp. 1 were collected in Paraitinguinha stream of the Tietê River basin, in the municipality of Salesópolis, São Paulo State, and those of Neoplecostomus sp. 2 from São Domingos stream of the Rio Grande River basin, in the municipality of Muzambinho, Minas Gerais State. The genetic variability of the two populations was estimated by Nei's expected heterozygosity and was considered lower than average for populations of freshwater fish. The proportion of polymorphic loci was low (only 5.26% for the locus Idh). The low frequency of heterozygosity for both populations revealed a high fixation of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Allozymes; Genetic variability; Neoplecostominae; Neotropical fishes.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000300021

Sex chromosome system ZZ/ZW in Apareiodon hasemani Eigenmann, 1916 (Characiformes, Parodontidae) and a derived chromosomal region
Provedor de dados: 74
Autores: Bellafronte,Elisangela; Schemberger,Michelle Orane; Artoni,Roberto Ferreira; Moreira Filho,Orlando; Vicari,Marcelo Ricardo.
Parodontidae fish show few morphological characteristics for the identification of their representatives and chromosomal analyses have provided reliable features for determining the interrelationships in this family. In this study, the chromosomes of Apareiodon hasemani from the São Francisco River basin, Brazil, were analyzed and showed a karyotype with 2n = 54 meta/submetacentric chromosomes, and a ZZ/ZW sex chromosome system. The study revealed active NORs located on pair 11 and additional 18S rDNA sites on pairs 7 and 22. The 5S rDNA locus was found in pair 14. It showed a pericentric inversion regarding the ancestral condition. The satellite DNA pPh2004 was absent in the chromosomes of A. hasemani, a shared condition with most members of Apareiodon....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cytogenetics; FISH; 18S rDNA; 5S rDNA; Neotropical fishes.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000500010

Taxonomic revision of the Rineloricaria species (Siluriformes: Loricariidae) from the Paraguay River basin
Provedor de dados: 83
Autores: Vera-Alcaraz,Héctor S.; Pavanelli,Carla S.; Zawadzki,Cláudio H.
Species of the genus Rineloricaria from the Paraguay River basin were revised, the following species and geographic distributional patterns were found: R. aurata, Paraguay River basin in Brazil and Paraguay, rio Guaporé in Brazil; R. cacerensis, Paraguay River near Cáceres in Brazil; R. lanceolata, Paraguay River basin in Brazil and Paraguay, Guaporé, Ji-Paraná, Purus, Solimões, and Araguaia rivers in Brazil, Marañón and Madre de Dios rivers in Peru; R. parva, Paraguay River basin in Brazil and Paraguay, Paraná River in Argentina, Uruguay River in Brazil. Loricaria hoehnei is proposed as a new junior synonym of R. lanceolata. A key to the species of Rineloricaria from the Paraguay River basin is provided.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Loricariinae; Neotropical fishes; Suckermouth armored catfishes.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000200006

Moenkhausia rubra, a new species from rio Juruena, upper rio Tapajós basin, Brazil (Characiformes: Characidae)
Provedor de dados: 83
Autores: Pastana,Murilo N. L.; Dagosta,Fernando C. P.
Moenkhausia rubra, new species, is described from the upper rio Juruena, rio Tapajós basin, Mato Grosso, Brazil. The new species is distinguished from its congeners, except M. hemigrammoidesand M. nigromarginata, by the dark pigmentation on the anteriormost rays of both dorsal and anal fins. Moenkhausia rubrais distinguished from the aforementioned species by the number of branched anal-fin rays 17-20 (vs. 20-25), presence of a dark blotch on the caudal peduncle extending to middle caudal-fin rays, absence of longitudinal black zigzag stripes between longitudinal rows of scales on body, and other details of coloration.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon; Moenkhausia nigromarginata; Neotropical fishes; Ostariophysi; Tetra.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000200389

Gross morphology of the brain of Pseudopimelodus bufonius (Valenciennes, 1840) (Siluriformes: Pseudopimelodidae)
Provedor de dados: 83
Autores: Abrahão,Vitor Pimenta; Shibatta,Oscar Akio.
The gross morphology of the brain of the pseudopimelodid Pseudopimelodus bufonius is described and compared with congeners. Observations were made on removed brains after elimination of bones from the top of the skull and severing of the cranial nerves and the spinal cord. Nine morphometric characters associated with the major subdivisions of the brain were identified, seven of which revealed significant differences among the species examined. The corpus cerebelli in all examined species of the genus is the largest structure of the brain. The behavior of the species of Pseudopimelodus is still unknown, but in other teleosts that condition is typically correlated with a higher degree of motor coordination. Relative size proportions of the tectum opticum,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Behavior; Catfishes; Comparative Morphology; Neotropical fishes; Neuroanatomy.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252015000200255

Feeding habits of fish from a stream in the savanna of Central Brazil, Araguaia Basin
Provedor de dados: 83
Autores: Melo,Cesar Enrique de; Machado,Francisco de Arruda; Pinto-Silva,Vangil.
The objective of the present study was to determine the composition of the diet of fish and its relation to the condition of canopy along a stream in the savanna of Central Brazil. Fish were collected monthly from April 1994 to March 1995. A total of 3872 individuals belonging to 82 species were captured and 1606 of them had their stomach content analysed. Allochthonous resources were widely used by fish. Although some fish groups do present generalist habits, most of the species can be included in well-defined trophic groups. Piscivores were abundant only during the flooding season when they occupied the stream looking for food and reproduction sites. Deforestation of the riparian forest has negative effects on the fish populations that depend on...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Neotropical fishes; Fish ecology; Trophic interactions; Riparian forest; Cerrado.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252004000100006

A new species of the Hypostomus cochliodongroup (Siluriformes: Loricariidae) from the rio Aripuanã basin in Brazil
Provedor de dados: 83
Autores: Zawadzki,Cláudio H.; Carvalho,Pedro Hollanda.
A new species of Hypostomus, H. dardanelos, is described from the rio Aripuanã basin, a southern tributary to the rio Madeira, in northern Mato Grosso State, Brazil. The new species is assigned to the Hypostomus cochliodon group by the possession of few teeth, spoon-shaped teeth, angle between dentaries usually less than 80°, and by the absence of a notch between hyomandibular and the metapterygoid. The new species can be diagnosed from its congeners by its unique color pattern of yellowish-brown ground color covered by well-defined dark spots of relatively equal size, evenly spaced and moderately set along the dorsal region of the body and fins, except on the ventrolateral region of the caudal peduncle and proximal region of anal and caudal fins, which...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon basin; Catfish; Hypostominae; Neotropical fishes; Taxonomy.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000100043

A barrier to upstream migration in the fish passage of Itaipu Dam (Canal da Piracema), Paraná River basin
Provedor de dados: 83
Autores: Fontes Júnior,Hélio Martins; Castro-Santos,Theodore; Makrakis,Sergio; Gomes,Luiz Carlos; Latini,João Dirço.
The majority of the fish passages built in the Neotropical region are characterised by low efficiency and high selectivity; in many cases, the benefits to fish populations are uncertain. Studies conducted in the Canal da Piracema at Itaipu dam on the Parana River indicate that the system component designated as the Discharge channel in the Bela Vista River (herein named Canal de deságue no rio Bela Vista or CABV), a 200 m long technical section, was the main barrier to the upstream migration. The aim of this study was to evaluate the degree of restriction imposed by the CABV on upstream movements of Prochilodus lineatus and Leporinus elongatus, Characiformes. Fish were tagged with passive integrated transponders (PIT tags) and released both downstream and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fish migration; Nature-like; Neotropical fishes; PIT-tag; Telemetry.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000400002

Preliminary examination of food web structure of Nicola Lake (Taim Hydrological System, south Brazil) using dual C and N stable isotope analyses
Provedor de dados: 83
Autores: Garcia,Alexandre M.; Hoeinghaus,David J.; Vieira,João P.; Winemiller,Kirk O.; Marques,David M. L. Motta; Bemvenuti,Marlise A.
Taim Ecological Reserve is located within the Taim Hydrological System and was created to protect a heterogeneous and productive landscape harboring exceptional biological diversity in southern Brazil. Using stable isotope ratio analyses of carbon (delta13C) and nitrogen (delta15N), we provide a preliminary description of the food web structure, including estimates of production sources supporting fish populations and vertical trophic structure, within a representative lake of this system. A total of 21 organisms (5 macrophytes, 3 mollusks and 13 adult fishes) representing 16 species were collected for isotope analysis. Fishes had delta13C values ranging from -24.30º/oo to -28.31º/oo , showing concordance with the range of values observed for macrophytes...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Subtropical wetland; Neotropical fishes; Patos-Mirim Lagoon complex; Long-Term Ecological Research (LTER); Brazilian Long Term Ecological Research (PELD).
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000200014

Fish assemblages of tropical floodplain lagoons: exploring the role of connectivity in a dry year
Provedor de dados: 83
Autores: Petry,Ana Cristina; Agostinho,Angelo Antonio; Gomes,Luiz Carlos.
Irregular rainfall and pronounced reductions of the hydrometric level in the year 2000 resulted in drastically altered hydrological connectivity of lentic environments in the upper Paraná River floodplain. The objective of the present work was to examine spatial and temporal patterns of fish assemblage attributes and structure in relation to limnological variables associated with hydrological connectivity. Fish were collected quarterly by seining in the marginal areas of 15 lagoons belonging to two biotopic categories (connected and disconnected). Variation in assemblage composition reflected the degree of hydrological connectivity. Values of assemblage attributes (species richness, density and biomass) were significantly lower in connected lagoons than in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Neotropical fishes; Fish assemblage structure; Hydrological connectivity; Floodplain.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252003000200005

Two new species of Hypostomus Lacépède (Teleostei: Loricariidae) from the upper rio Paraná basin, Central Brazil
Provedor de dados: 83
Autores: Zawadzki,Cláudio H.; Weber,Claude; Pavanelli,Carla S.
Two new species of Hypostomus Lacépède (Teleostei: Loricariidae) from the rio Paranaíba and rio Grande basins, both in the upper rio Paraná basin, central Brazil, are described herein. One of them is distinguished from all congeners, except H. albopunctatus, by having the pectoral-fin spine length equal to or smaller than the pelvic-fin spine. From H. albopunctatus, it is distinguished by having round dark spots (vs. pale) on body and fins. The second species is distinguished from all congeners, except H. multidens and H. ternetzi, by having more than 115 teeth (vs. less than 109) per ramus on dentary and premaxilla. It is distinguished most readily from H. ternetzi by having teeth with two symmetrical (vs. asymmetrical) cusps. It is distinguished from H....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Catfishes; Neotropical fishes; Siluriformes; Taxonomy.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000300013

The cascudos of the genus Hypostomus Lacépède (Ostariophysi: Loricariidae) from the rio Iguaçu basin
Provedor de dados: 83
Autores: Garavello,Julio César; Britski,Heraldo Antônio; Zawadzki,Claudio Henrique.
We reviewed several large collections of the genus Hypostomus from the rio Iguaçu basin summing up to 793 specimens mainly from the Laboratório de Ictiologia do Departamento de Ecologia e Biologia Evolutiva from Universidade Federal de São Carlos, from fish collection of Núcleo de Pesquisas em Limnologia, Ictiologia e Aquicultura da Universidade Estadual de Maringá, and from the Museu de História Natural do Capão da Imbuia. Hypostomus albopunctatus, H. commersoni, H. derbyi, and H. myersi are redescribed and Hypostomus nigropunctatus is described as a new species. A practical key for identification of Hypostomus species from the rio Iguaçu is also provided.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Hypostominae; Neotropical fishes; Systematics; Taxonomy.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000200005

A new species of Hypostomus Lacépède, 1803 (Siluriformes: Loricariidae) from the rio Tocantins-Araguaia basin, Brazil
Provedor de dados: 83
Autores: Zawadzki,Cláudio Henrique; Oliveira,Renildo Ribeiro de; Debona,Tiago.
Hypostomus delimaiis described from the rio Tocantins, Tocantins State, and from the rio Araguaia, Pará, and Tocantins States, Brazil. The new species is distinguished from all other Hypostomusspecies, except from H. carinatus, H. hoplonites, and H. watwata, by the presence of five to eight (mode seven) predorsal plates limiting posterior border of the supraoccipital bone (vs. one to three plates). It can be distinguished from H. carinatus, H. hoplonites, and H. watwata by having pale spots over darker background on body and fins (vs. dark spots over lighter background). The species was only found in the middle stretches of the rio Tocantins-Araguaia basin. The first collection of specimens assigned to the new species was done in the rio Tocantins before...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cantão; Catfish; Hydroelectric; Hypostominae; Neotropical fishes; Taxonomy.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000100073

Checklist comparison and dominance patterns of the fish fauna at Taim Wetland, South Brazil
Provedor de dados: 83
Autores: Garcia,Alexandre M.; Bemvenuti,Marlise A.; Vieira,João P.; Marques,David M. L. Motta; Burns,Marcelo D. M.; Moresco,Alex; Condini,Mario Vinicius L.
Taim Hydrological System is a unique subtropical wetland in southern Brazil harboring an exceptional biological diversity. In 1978, an ecological reserve was established to protect part of this area from increasing anthropogenic impacts in its surroundings. Fishes have been poorly investigated in this system. Based on a multi-gear sampling study encompassing several years (2001-2005), and on comparisons with previous fish inventories, we provide an up-to-date species list of fishes occurring in the Taim Wetland. In addition, we made the first preliminary description of fish dominance patterns found in the main lakes of the system (Flores, Nicola, Jacaré and Mangueira). Checklist comparison resulted in 62 fish species distributed in 24 families, with...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Subtropical wetland; Neotropical fishes; Ecological Reserve; Invasive species; Patos-Mirim Lagoon complex.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000200012

Two new species of the Hypostomus cochliodon group (Siluriformes: Loricariidae) from the rio Paraguay basin, with a redescription of Hypostomus cochliodonKner, 1854
Provedor de dados: 83
Autores: Tencatt,Luiz F. C.; Zawadzki,Cláudio H.; Froehlich,Otávio.
Hypostomus cochliodon group is a monophyletic clade of 20 valid species of Neotropical armored catfishes that is widely distributed throughout South America. Recently, specimens identified as H. cochliodon from the type locality and nearby localities were examined, and found to include representatives of more than one species. A redescription of H. cochliodon is provided, with a description of two new species, one from the Bodoquena Plateau and another from several localities of the rio Paraguay basin. A lectotype for H. cochliodon is designated herein, since the previous designation is invalid. Hypostomus cochliodon is diagnosed from all other species of the H. cochliodon group by having the opercle almost completely covered laterally by thick layer of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Armored catfish; Hypostominae; Neotropical fishes; Rio Cuiabá; Taxonomy.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000300585

Genetic variability in four samples of Neoplecostomus yapo (Teleostei: Loricariidae) from the rio Paranapanema basin, Brazil
Provedor de dados: 83
Autores: Philippsen,Juliana S.; Renesto,Erasmo; Gealh,Ana Maria; Artoni,Roberto F.; Shibatta,Oscar A.; Zawadzki,Claudio H.
Four samples of Neoplecostomus yapo were analyzed through the allozyme electrophoresis technique in corn starch gel. The allozyme pattern was similar to those found in N. paranensis with 24 loci scored. Two samples (ribeirão Atlântico and ribeirão Uraí) showed monomorphic bands for all 24 loci, whereas the other two (rio Verde and rio Fortaleza) showed 8.3% of polymorphic loci. The He genetic variability estimates for the rios Verde and Fortaleza populations were 0.0195 and 0.0179, respectively, too much inferior to the mean heterozygosity summed to species from the whole world (0.051). The Wright statistical values F IS = 0.5181, F IT = 0.5681 and F ST = 0.1039 and the genetic distance of Nei values showed that the four samples are genetically very...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Allozymes; Genetic variation; Neoplecostominae; Neotropical fishes; Siluriformes.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252009000100004

Revalidation and redescription of Steindachnerina nigrotaenia and redescription of S. insculpta (Characiformes: Curimatidae)
Provedor de dados: 83
Autores: Britski,Heraldo A.; Melo,Bruno F.; Vari,Richard P.; Oliveira,Claudio.
ABSTRACT Steindachnerina nigrotaenia is resurrected from the synonym of S. brevipinna and considered a valid species. The previous designation of the lectotype of S. nigrotaenia is considered invalid and a new lectotype is designated herein. Steindachnerina nigrotaenia and S. insculpta are redescribed based on type specimens and on additional material from the rio Paraguai and the upper rio Paraná basins, respectively. The two species can be separated by the number of scales of the lateral line and of the transverse series and by phylogenetic analyses of molecular data.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ostariophysi; Neotropical fishes; Systematics; Taxonomy.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252019000100207

Harttia absaberi, a new species of loricariid catfish (Siluriformes: Loricariidae: Loricariinae) from the upper rio Paraná basin, Brazil
Provedor de dados: 83
Autores: Oyakawa,Osvaldo Takeshi; Fichberg,Ilana; Langeani,Francisco.
A new species of Harttia, tribe Harttiini, is described from tributaries of upper portions of rio Paraná drainage. The new species, the smallest known species of the genus, attaining up to 74.0 mm of standard length, can be distinguished from its congeners by the combination of the following characters: abdomen completely covered by plates, a single preanal plate, plates of the gular area in broad contact with the canal plate. Harttia absaberi is the second species of the genus known from the upper portion of rio Paraná drainage.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Harttiini; Loricarioidea; Neotropical fishes; Ostariophysi; Taxonomy.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000400779

A new species of Farlowella (Siluriformes: Loricariidae) of the F. nattereri species-group from the rio Xingu basin, Mato Grosso, Brazil, with comments on Farlowella jauruensis , a poorly-known species from the upper rio Paraguai basin
Provedor de dados: 83
Autores: Ballen,Gustavo A.; Pastana,Murilo N. L.; Peixoto,Luiz A. W.
ABSTRACT A new species of Farlowella is described from eighteen specimens collected in the upper rio Xingu basin, Mato Grosso State, Brazil. The new species is a member of the Farlowella nattereri species-group and can be distinguished from other members of the group, with exception of Farlowella jauruensis , by exhibiting a proportionally shorter snout. The new species is distinguished from F. jauruensis by differences on the cleithrum and plate morphology, by counts of pelvic and caudal-fin rays, and by the color pattern of the snout. The discovery of new lots of F. jauruensis , a species so far known only from the holotype, is also herein reported. This discovery represents a considerable expansion of the geographic distribution and of the number of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon; Brazilian shield; Loricariinae; Neotropical fishes; Ostariophysi.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000300215

Allozyme analysis of the four species of Hypostomus (Teleostei: Loricariidae) from the Ivaí river, upper Paraná river basin, Brazil - doi: 10.4025/actascibiolsci.v35i4.16355
Provedor de dados: 3
Autores: Paiva, Suzana de; Universidade Estadual de Maringá; Zawadzki, Claudio Henrique; Universidade Estadual de Maringa; Ruvulo-Takasusuki, Maria Claudia Colla; Universidade Estadual de Maringá; Lapenta, Ana Silvia; Universidade Estadual de Maringá; Renesto, Erasmo; Universidade Estadual de Maringá.
Allozyme electrophoresis analysis were performed in four species of Hypostomus (Loricariidae), H. albopunctatus, H. hermanni, H. regani, e Hypostomus sp. 1/NUP 5612 from the Ivaí river, a tributary of the upper Paraná river. The study of 14 loci revealed diagnostic characters and exclusive alleles in a low frequency. The heterozygosity ranged from 0.000 in H. albopunctatus to 0.199  in H. hermanni, which was higher than the heterozygosity in other samples of Hypostomus in literature, as well as in other fish groups. Hypostomus albopunctatus and H. regani revealed higher similarity (I = 0.804), while H. hermanni and Hypostomus sp. 1/NUP 5612 showed the least genetic identity (I = 0.569). All samples were genetically distinguished, despite there were several...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: 2.02.00.00-5 catfish; Heterozygosity; Neotropical fishes; Genetic variability; Siluriformes Genética.
Ano: 2013
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/16355

Karyotype description of possible new species of the Hypostomus ancistroides complex (Teleostei: Loricariidae) and other Hypostominae - doi: 10.4025/actascibiolsci.v34i2.9318
Provedor de dados: 3
Autores: Endo, Kátia Sayuri; Universidade Estadual de Maringá; Martinez, Emanuel Ricardo Monteiro; Universidade Estadual Paulista “Júlio de Mesquita Filho" / Botucatu-SP; Zawadzki, Claudio Henrique; Universidade Estadual de Maringa; Paiva, Luiz Ricardo de Souza; Universidade Estadual Paulista “Júlio de Mesquita Filho" / Botucatu-SP; Júlio Júnior, Horácio Ferreira; Universidade Estadual de Maringá.
Cytogenetic analyses were performed in four species of the Hypostominae subfamily, three from Hypostomus (Hypostomini) genus and Rhinelepis aspera (Rhinelepini). Three populations of Hypostomus ancistroides were analyzed, which had 2n=68 chromosomes, but presented different karyotype formulas. Hypostomus regani and H. strigaticeps, both from Ivaí river, showed 2n=72 chromosomes with two distinct cytotypes. In turn, R. aspera of the upper Paraná river basin presented 2n=54 chromosome. Multiple Nucleolar Organizer Regions (NORs) have been evidenced by silver nitrate staining in species of Hypostomus and single NOR in R. aspera. The observed variation in the chromosome number and the marked variability in karyotype formulas and NORs reveal a certain amount of...
Tipo: Estudos cromossômicos
Palavras-chave: 2.02.04.00-0 chromosomal evolution; Cryptic species; Neotropical fishes; NOR Genética Animal.
Ano: 2012
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/9318

Longitudinal patterns of fish assemblages in mountain streams from tropical forest biome
Provedor de dados: 49
Autores: Silva,João Fernando Marques da; Raio,Cibele Bender; Bernardino,Débora Fernandes Silva; Bennemann,Sirlei Terezinha.
The aim of this study was to verify structure patterns in fish assemblages in mountain streams of the Rio Tibagi basin through the characterization of spatial and temporal variations in the composition of fish species. Samples were collected in three segments of the Varanal, João Pinheiro and Rio Preto streams. We collected 1154 specimens belonging to 21 species. The most abundant orders were Characiformes (59.01 ± 2.84%) and Siluriformes (39.34 ± 2.82%). Phalloceros harpagos was the most abundant species with 433 individuals, followed by Trichomycterus aff.davisi, with 292 individuals. No temporal variations (between seasons) were detected, but the cluster analysis suggests a separation of species composition between the segments closer to the headwaters...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ichthyofauna; Freshwater fishes; Neotropical fishes; Low order streams; Tibagi river basin.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032013000300064

The fish fauna of the Jacaré-Guaçu River basin, Upper Paraná River basin
Provedor de dados: 49
Autores: Esguícero,André Luiz Henríques; Arcifa,Marlene Sofia.
This study aimed to evaluate the fish fauna composition and distribution in different environments, up- and downstream the Gavião Peixoto Dam, in the Jacaré-Guaçu River basin. Most of the sampled ichthyofauna is autochthonous, and the majority of the species belongs to the orders Characiformes and Siluriformes. The order Characiformes comprised most of the specimens caught, Astyanax altiparanae being the most abundant species. All the studied environments were characterized by the massive occurrence of accidental species and low similarity between their ichthyofauna. In general, a greater number of species and higher values of the diversity index were observed downstream of the dam. The fish diversity in the studied habitats was positively correlated with...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Neotropical fishes; Stream ecology; Communities' structure; Freshwater fishes; Environmental degradation.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032011000100010

Short-term cold storage of sperm from six neotropical characiformes fishes
Provedor de dados: 52
Autores: Marques,Simone; Godinho,Hugo Pereira.
Sperm of the following Neotropical Characiformes fish species were tested for cold storage: Brycon lundii, Piaractus mesopotamicus, Leporinus elongatus, Leporinus friderici, Prochilodus lineatus and Prochilodus marggravii. Each sperm sample was split into two aliquots. The first was placed into a plastic bag with air or oxygen and the second, in a plastic tube with air. The samples were maintained at temperatures between 1.7-4.9 ºC. The rate of sperm motility was estimated using a 50 mM NaCl solution as the activating solution. The shortest sperm storage duration (7 h) was recorded for L. friderici, when the sperm motility rate reached ~ 30%, whereas the longest duration (20 h) was obtained with the sperm of P. lineatus. A fertilisation test using...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cool storage of sperm; Sperm motility; Semen; Neotropical fishes.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132004000500016