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| Registros recuperados: 70 | |
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| Azevedo-Santos,Valter M.; Britski,Heraldo A.; Oliveira,Claudio; Benine,Ricardo C.. |
| Abstract: The Rio Sapucaí basin, in Minas Gerais State, Brazil, is one of the many watersheds of the upper Rio Paraná system. Ichthyofauna surveys in this basin, in general, are scarce. In addition, small rivers and streams of the region have been targets of anthropogenic actions (e.g., pollution) - which suggest that more ichthyological studies must be performed within the watershed. In this study we provide a survey of species that occur within three streams of the lower Rio Sapucaí basin. Samples were collected in April, July, and November 2017 and in May 2018. Collections resulted in 349 individuals belonging to 28 species, five orders, and 12 families. Among our findings are three putatively undescribed species and the first record of Oligosarcus... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fishes; Inventory; Oligosarcus argenteus; Pareiorhina hyptiorhachis; Undescribed species. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032019000100309 |
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| Porto-Foresti,Fábio; Oliveira,Claudio; Maistro,Edson Luis; Foresti,Fausto. |
| A study was made of the frequency of B-chromosomes and the population density of Astyanax scabripinnis paranae (Pisces, Characidae, Tetragonopterinae) from three stretches of the Cascatinha stream (Botucatu, SP). In the first stretch the population was estimated to be about 212 individuals and among 35 karyotyped specimens, 23 carried one macro B-chromosome; in the second stretch the population was estimated to be about 650 individuals and among 20 specimens karyotyped, two possessed one macro B-chromosome; in the third stretch the population was estimated to be about 107 individuals and among 10 specimens karyotyped, one carried one macro B-chromosome. A significant difference was observed in the frequency of macro B-chromosomes in females (57%) and males... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84551997000300004 |
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| Hilsdorf,Silva; Oliveira,Claudio; Lima,Flávio César Thadeo de; Matsumoto,Cristianne Kayoko. |
| The genus Brycon, the largest subunit of the Bryconinae, has 42 valid species distributed from southern Mexico to the La Plata River in Argentina. Henochilus is a monotypic genus, comprising a single species (H. wheatlandii) found in the upper Rio Doce basin. In the present study, partial sequences of the mitochondrial gene 16S were obtained for fifteen species of Brycon and for Henochilus wheatlandii. The results showed that the genus Brycon is paraphyletic, since Henochilus is the sister-group of B. ferox and B. insignis. The most basal species analyzed were the trans-Andean species B. henni, B. petrosus, and B. chagrensis. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Phylogeny; Molecular systematics; Mitochondrial DNA; Fish evolution; Systematic. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200034 |
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| Nirchio,Mauro; Oliveira,Claudio; Ferreira,Irani Alves; Granado,Angel; Ron,Ernesto. |
| The karyotype and chromosomal characteristics of the characid fish Triportheus venezuelensis were investigated using differential staining techniques (C-banding, Ag-NOR staining) and fluorescent in situ hybridization (FISH) with an 18S rDNA probe. The diploid chromosome number (2n = 52), karyotype composition and sex chromosome determination system of the ZZ/ZW type were the same as previously described in other species of the genus Triportheus. However, extensive variation regarding nucleolus organizer regions (NOR) different from other species was observed. 18S rDNA sequences were distributed on nine chromosome pairs, but the number of chromosomes with Ag-NORs was usually lower, reaching a maximum of four chromosomes. When sequential staining experiments... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: 18S rDNA; Ag-NORs; C-band; FISH; Fish cytogenetics; Sex chromosomes. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000100007 |
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| Carvalho,Margarida Lima; Oliveira,Claudio; Foresti,Fausto. |
| 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... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1998 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000100009 |
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| Santos,Lessandra Viviane De Rosa; Foresti,Fausto; Martins,Cesar; Oliveira,Claudio; Wasko,Adriane Pinto. |
| Cytogenetic analyses were performed in Cyphocharax modestus, collected at Paranapanema River and Tietê River (São Paulo State, Brazil). A karyotype with 2n = 54 chromosomes was observed in the animals from both Brazilian freshwater river systems. One to four B chromosomes were also detected in individuals from the Paranapanema River, which represents the probable first report of more than a single supernumerary element in a species of the Curimatidae group. C-banding revealed centromeric and telomeric heterochromatin blocks in several chromosomes of the normal karyotype complement of C. modestus. Moreover, while some B chromosomes were characterized by the complete absence of C-bands, others were totally heterochromatic. Although there was a prevalence of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: B chromosomes; C-banding; Curimatidae; Cyphocharax modestus; Supernumerary chromosomes. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200019 |
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| Porto-Foresti,Fábio; Oliveira,Claudio; Tabata,Yara A.; Rigolino,Marcos G.; Foresti,Fausto. |
| In salmonid species, nucleolar organizing regions (NORs) have frequently been found on a single chromosome pair. However, some other, smaller yet active NORs have also been described. In the present study, NORs were found to be located in different positions on the chromosomes of 12 rainbow trout samples (11 cultivated and one naturalized stocks). Three phenotypes were found: 1) NORs located on two submetacentric chromosomes, in a subterminal position on the short arm (AA); 2) NORs located on two submetacentric chromosomes, in a subterminal position on the long arm (BB); and 3) NORs located on two submetacentric chromosomes, one in a subterminal position on the short arm, and the other in a subterminal position on the long arm (AB). Phenotype AA was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: NOR polymorphism; Fish cytogenetics; Rainbow trout. |
| Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572002000400009 |
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| Azevedo,Marisa F.C.; Oliveira,Claudio; Pardo,Belén G.; Martínez,Paulino; Foresti,Fausto. |
| The fish order Pleuronectiformes, composed of 14 families, has two suborders: Psettodoidei (with one family) and Pleuronectoidei (with thirteen families). The relationships among families of Pleuronectoidei and among the genera of their families have extensively been debated and a consensus has not yet been reached. In the present study, partial sequences of the 12S and 16S mitochondrial rRNA genes were obtained from 19 species belonging to the families Achiridae, Bothidae, Cynoglossidae, Paralichthyidae, Pleuronectidae, Scophthalmidae, and Soleidae. Additional sequences of 42 pleuronectiform species were obtained from GenBank. Phylogenetic analyses were conducted by the methods of maximum-parsimony, maximum-likelihood and Bayesian inference. Our results... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Phylogeny; Molecular systematics; Mitochondrial DNA; Fish evolution; Flatfishes. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200023 |
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| Maistro,Edson Luis; Oliveira,Claudio; Foresti,Fausto. |
| Among four specimens of Astyanax scabripinnis sympatrically collected from the Tamanduá stream (State of São Paulo, Brazil), three, named cytotype I, had 2n = 50 chromosomes (6M + 26SM + 4ST + 14A) and a fundamental number (FN) of 86, and one specimen, named cytotype II, had 2n = 48 chromosomes (6M + 28SM + 4ST + 10A) and FN = 86. Besides the difference in diploid number, the cytotypes showed a clear difference in the distribution of constitutive heterochromatin. One NOR-bearing chromosome pair was detected in both cytotypes and one specimen of cytotype I had multiple NORs (tree chromosome pairs). Robertsonian translocations and an increase or loss of heterochromatin are proposed to explain the karyotypic divergence observed. Some aspects related to the... |
| Tipo: Info:eu-repo/semantics/other |
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| Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572000000200021 |
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| Martinez,Emanuel Ricardo Monteiro; Nirchio,Mauro; Granado,Angel; Foresti,Fausto; Oliveira,Claudio. |
| Cytogenetic analyses performed in Cephalosilurus apurensis, Microglanis aff. cottoides and Pseudopimelodus bufonius revealed that the three species have 2n = 54 chromosomes: C. apurensis presented six metacentric (M), 28 submetacentric (SM), 14 subtelolocentric (ST), and six acrocentric (A) chromosomes, while M. aff. cottoides showed 10M, 32SM, 10ST and 2A, and P. bufonius had 12M, 30SM and 12ST. The nucleolus organizer regions (NORs) were present on the short arm of a middle-sized ST pair, identified as pair 19, in C. apurensis NORs were found on the short arm of a middle-sized ST (pair 23) and on the long arm of a middle-sized ST (pair 22) in M. aff. cotttoides and on the short arm of three middle-sized ST pairs, identified as pairs 9, 10 and 11, in P.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype; Chromosomes; C-banding; Ag-NOR; Fish. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000400015 |
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| Maistro,Edson Luis; Foresti,Fausto; Oliveira,Claudio. |
| The absence of longitudinal bands in fish chromosomes has been associated with technical problems in chromosome preparations or the absence of a structural compartmentalization in the fish genome. In the present study, a R-banding pattern was obtained using a replication banding technique by in vivo treatment with 5-bromodeoxyuridine (5-BrdU). G-banding patterns were obtained after trypsin treatment and also after chromosome cleavage by in situ treatment with the restriction endonuclease BamHI. A similar G-banding pattern was also obtained after cleavage with the endonuclease HinfI. Presence of a resolute R- and G-banding patterns shows that Astyanax scabripinnis paranae chromosomes could present an isochore-like structure similar to that found in other... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571999000200011 |
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| Nirchio,Mauro; Martinez,Emanuel Ricardo Monteiro; Foresti,Fausto; Oliveira,Claudio. |
| Despite their ecological and economical importance, fishes of the family Ariidae are still genetically and cytogenetically poorly studied. Among the 133 known species of ariids, only eight have been karyotyped. Cytogenetic analyses performed on Genidens barbus and Sciades herzbergii revealed that both species have 2n = 56 chromosomes and Cathorops aff. mapale has 2n = 52 chromosomes: Genidens barbus has 10 Metacentrics (M), 14 Submetacentrics (SM), 26 Subtelocentrics (ST), and 6 Acrocentrics (A), Sciades herzbergii has 14M, 20SM, 18ST and 4A, whereas Cathorops aff. mapale has 14M, 20SM, and 18ST. The nucleolus organizer regions (NORs) were found in a single chromosome pair on the short arm of a large-sized ST pair in Genidens barbus and on the short arm of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cytogenetics; Ag-NORs; Chromosome evolution; Chromosome rearrangements; Fish. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000200011 |
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| Registros recuperados: 70 | |
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