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| Registros recuperados: 87 | |
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| Lessa,Gisele; Corrêa,Margaret M. O; Pessôa,Leila M; Zappes,Ighor A. |
| Kerodon rupestris (Wied, 1820) is the most specialized species among caviid rodents and is endemic to the extensive rocky outcrops in the semi-arid region in Brazil. Herein we describe different karyotypes for K. rupestris, based on samples collected in Itapajé, Ceará (CE), Iraquara in Bahia (BA), and Botumirim in Minas Gerais (MG). Our samples included northern, center and southern populations in the range of the species distribution. The results were compared with a karyotype from Pernambuco previously described for the species. The diploid number (2n = 52) was constant among the analyzed population samples, but the fundamental number (FN) varied from 92 in Itapajé (CE) and Iraquara (BA), to 94 in Botumirim (MG). Pericentric inversions affecting one... |
| Tipo: Info:eu-repo/semantics/report |
Palavras-chave: C-Bands; Cytogenetics; Kerodon rupestris; NOR. |
| Ano: 2013 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-93832013000200013 |
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| Barranco, P.; Cabrero, J.; Camacho, J.P.M.; Pascual, F.. |
| Morphological and cytogenetic analyses of a spontaneous gynandromorph of Pycnogaster inermis, found in a natural population in the Spanish Sierra Nevada, have shown that the left side was male and the right side female, with almost perfect bilateral symmetry. Ventral valves of the ovipositor were very short, appearing as two spurs; dorsal valves were longer but still shorter than normal. The specimen had an apparently normal testis on the left side and a well-developed ovary on the right side. Cytogenetic analysis revealed the presence of 2n = 28 + X0 chromosomes in the testis and 2n = 28 + XX in the ovary, the same as standard males and females, respectively, of this species. This suggests that the gynandromorphism occurred at a very early developmental... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Gynandromorphism; Cytogenetics; Pycnogaster inermis; Tettigoniidae; Orthoptera. |
| Ano: 1995 |
URL: http://www.repository.naturalis.nl/record/504051 |
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| Bellafronte,Elisangela; Mariguela,Tatiane Casagrande; Pereira,Luiz Henrique Garcia; Oliveira,Claudio; Moreira-Filho,Orlando. |
| In the past years, DNA barcoding has emerged as a quick, accurate and efficient tool to identify species. Considering the difficulty in identifying some Parodontidae species from the La Plata basin and the absence of molecular data for the group, we aimed to test the effectiveness of DNA barcoding and discuss the importance of using different approaches to solve taxonomic problems. Eight species were analyzed with partial sequences of Cytochrome c oxidase I. The mean intraspecific K2P genetic distance was 0.04% compared to 4.2% for mean interspecific K2P genetic distance. The analyses of distance showed two pairs of species with K2P genetic divergence lower than 2%, but enough to separate these species. Apareiodon sp. and A. ibitiensis, considered as the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Apareiodon; COI gene; Cytogenetics; Fish identification; Morphology. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000300497 |
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| Castro,Jonathan P.; Moura,Maurício O.; Moreira-Filho,Orlando; Shibatta,Oscar A.; Santos,Mateus H.; Nogaroto,Viviane; Vicari,Marcelo R.; Almeida,Mara C. de; Artoni,Roberto F.. |
| Two populations of the Astyanax scabripinniscomplex, isolated by a waterfall with over 100 meters depth and inhabiting different altitudes of the same river (1850 m a.s.l. and 662 m a.s.l.) were compared in reproductive data, geometric morphometry, tooth morphology, anal-fin rays counts, and karyotype, in order to test the hypothesis of speciation between the two populations. The results in the geometric morphometry analysis showed differences between the populations. Discriminant function analysis (DFA) and canonical variance analysis revealed sexual dimorphism. Secondary sexual characters, such as hooks in the anal fin rays of the males are absent in the lower altitude population. Both populations had the same macro karyotype structure, except for the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allopatric populations; Cytogenetics; Evolution; Geometric morphometry; Paraíba do Sul River. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000200429 |
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| Carvalho,Rafael Augusto de; Sanchez,Sebástian; Swarça,Ana Claudia; Fenocchio,Alberto Sergio; Martins-Santos,Isabel C.; Dias,Ana Lúcia. |
| This study presents chromosomal data of Megalonema platanum from rio Tibagi, Paraná, Brazil and from rio Paraná, Argentina. The diploid number was equal 54 with karyotype composition of 24m+16sm+2st+12a in both populations. The AgNOR sites were detected in the terminal position of a submetacentric pair of the two analyzed populations, coinciding with secondary constrictions on the short arm of pair 15. CMA3 and FISH with 18S rDNA probe displayed fluorescent signals that correspond to the AgNOR sites and secondary constriction. The presence of a small acrocentric supernumerary chromosome can be observed in M. platanum from rio Tibagi, with centromeric heterochromatin. Others heterochromatic blocks were evidenced in the terminal position of some chromosome... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cytogenetics; C-banding; CMA3; FISH; NORs; Pimelodidae. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000100017 |
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| Kowalski,Samantha; Paiz,Leonardo Marcel; da Silva,Maelin; Machado,Amanda de Souza; Feldberg,Eliana; Traldi,Josiane Baccarin; Margarido,Vladimir Pavan; Lui,Roberto Laridondo. |
| ABSTRACT Historically, there are divergences in the species allocation between Centromochlus and Tatia. This study aimed to generate the first cytogenetic data about Centromochlus and, by analyzing a population of Centromochlus heckelii from the Amazon River basin, to contribute as evidence to a historical taxonomic dilemma. Diploid number of 46 chromosomes and a heteromorphic pair was found in the female karyotypes, thus characterizing a ZZ/ZW sex chromosome system. Pale blocks of heterochromatin were located in centromeric regions of some chromosomes; however, the exclusive female chromosome (W) is almost entirely heterochromatic. AgNORs were detected in terminal position on the short arms of one acrocentric pair in males and two chromosome pairs in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Centromochlinae; Cytogenetics; Sex chromosome system; Taxonomy; ZZ/ZW. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252020000300203 |
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| Silva,Danillo S.; Peixoto,Luiz A. W.; Pieczarka,Julio C.; Wosiacki,Wolmar B.; Ready,Jonathan S.; Nagamachi,Cleusa Y.. |
| Eigenmannia species are widely distributed in the Neotropics, with eight valid species currently recognized. Populations of Eigenmannia from three locations in the eastern Amazon were investigated using cytogenetic and morphological techniques, revealing two taxa designated here as Eigenmannia sp. "A" and Eigenmannia sp. "B". The species differ in three morphometric characters, two meristic characters, and one osteological character. Eigenmannia sp. "A" presents 2n = 34 (22 m/sm+12 st/a) and Eigenmannia sp. "B" presents 2n = 38 (14 m/sm+24st/a) and simple differentiated sex chromosomes of the type XX/XY. In both species the Constitutive Heterochromatin (CH) rich in A-T bases is distributed in the centromeric region of all chromosomes. Eigenmannia sp. "B"... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cytogenetics; FISH; Knife fishes; Morphology; Sex chromosomes. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252015000200297 |
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| Bitencourt,Jamille de Araújo; Affonso,Paulo Roberto Antunes de Mello; Giuliano-Caetano,Lucia; Dias,Ana Lucia. |
| Few chromosomal reports are available for the endemic fish fauna from coastal basins in northeastern Brazil, and regional biodiversity remains partially or completely unknown. This is particularly true for Loricariidae, the most diverse family of armored catfishes. In the present work, allopatric populations of Hypostomus cf. wuchereri (Siluriformes: Loricariidae) from two basins in Bahia (northeastern Brazil) were cytogenetically analyzed. Both populations shared 2n = 76 chromosomes, a karyotype formula of 10m+18sm+48st/a (FN = 104) and single terminal GC-rich NORs on the second metacentric pair. Nevertheless, microstructural differences were detected by C-banding, fluorochrome staining and chromosomal digestion with restriction enzymes (Alu I, Bam HI,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biodiversity; Cytogenetics; Heterochromatin; Hypostominii. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000200008 |
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| Nirchio,Mauro; Masache,Maria Cecilia; Paim,Fabilene Gomes; Cioffi,Marcelo de Bello; Moreira Filho,Orlando; Barriga,Ramiro; Oliveira,Claudio; Rossi,Anna Rita. |
| ABSTRACT Parodontidae is a relatively small group of Neotropical characiform fishes consisting of three genera (Apareiodon, Parodon, and Saccodon) with 32 valid species. A vast cytogenetic literature is available on Apareiodon and Parodon, but to date, there is no cytogenetic data about Saccodon, a genus that contains only three species with a trans-Andean distribution. In the present study the karyotype of S. wagneri was described, based on both conventional (Giemsa staining, Ag-NOR, C-bands) and molecular (repetitive DNA mapping by fluorescent in situ hybridization) methods. A diploid chromosome number of 2n = 54 was observed in both sexes, and the presence of heteromorphic sex chromosomes of the ZZ/ZW type was detected. The W chromosome has a terminal... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ag-NOR; Cytogenetics; FISH; Heterochromatin; ZW sex chromosomes. |
| Ano: 2021 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252021000100203 |
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| Pamponet,Vanessa de Carvalho Cayres; Carneiro,Paulo Luiz Souza; Affonso,Paulo Roberto Antunes de Mello; Miranda,Viviam Souto; Silva Júnior,Juvenal Cordeiro; Oliveira,Claudine Gonçalves de; Gaiotto,Fernanda Amato. |
| Few reports are available about the ichthyofauna of typical semi-arid rivers, although the regional diversity has been constantly threatened by human activities, mainly related to impoundment and construction of dams. The goal of the present work was to evaluate using different methods, the population genetic structure of a characin fish, Astyanax aff. bimaculatus, widespread throughout hydrographic basins of Bahia, Northeastern Brazil. Morphological (meristic and morphometric data), cytogenetic (karyotype and Ag-NOR), and molecular (RAPD and SPAR) analyses were carried out in specimens collected upstream and downstream of Pedra Dam, in the main channel of Contas River (Contas River Basin), and in the Mineiro stream, which belongs to the adjacent Recôncavo... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Morphometry; Cytogenetics; RAPD; Population structure; Contas River. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000400010 |
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| Souza-Shibatta,Lenice; Pezenti,Larissa Forim; Ferreira,Dhiego Gomes; Almeida,Fernanda Simões de; Sofia,Silvia Helena; Shibatta,Oscar Akio. |
| Specimens of Pimelodellacaptured in the Miranda River, Pantanal of Mato Grosso do Sul State, present morphological features that could indicate at least four species. Therefore, karyotype analysis and molecular biology provided evidence that they were only two species, one showing 2n = 46, and the other, 2n = 52 chromosomes, with only 18% genetic similarity. The morphological analysis evidenced that the dorsal filament is a male characteristic and that the upper lobe of the caudal fin was variable and might or might not be elongated in both species. With respect to morphometric characters, the formation of two groups was evident, but with a small overlap of specimens between them. Among the species with filaments on the dorsal fin observed in the Pantanal,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cytotaxonomy; Cytogenetics; Multivariate morphometrics; RAPD. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000100101 |
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| Mariotto,Sandra; Centofante,Liano; Miyazawa,Carlos S.; Bertollo,Luiz Antonio Carlos; Moreira Filho,Orlando. |
| Cytogenetic and FISH analyses were performed in 30 Ancistrus cuiabae specimens from a bay near the town of Poconé, in the Pantanal of Mato Grosso, Brazil. The observed diploid number was 2n = 34 chromosomes for both sexes and three distinct katyotypic formulae were found, namely cytotype A (20m, 8sm, 6st, Fundamental Number/FN = 68; 6 males and 11 females), cytotype B (19m, 8sm, 6st, 1a, FN = 67; 8 males and 4 females) and cytotype C (18m, 8sm, 6st, 2a, FN = 66; a single male). NORs's analyses showed that these regions were located in distinct sites on the NOR-bearing chromosome pair, according to cytotypes. Thus, in cytotype A, NORs were located in the terminal region of the short arm of the second metacentric chromosome pair; in cytotype B, they were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cytogenetics; NOR; Pericentric inversion; Chromosomal evolution. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252009000400006 |
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| Registros recuperados: 87 | |
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