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| Kavalco,Karine Frehner; Brandão,Karina de Oliveira; Pazza,Rubens; Almeida-Toledo,Lurdes Foresti de. |
| Four populations of Astyanax hastatus Myers 1928 from the Guapimirim River basin (Rio de Janeiro State) were analyzed and three distinct cytotypes identified. These cytotypes presented 2n = 50 chromosomes, with 4M+8SM+10ST+28A (Cytotype A), 8M+10SM+14ST+18A (Cytotype B), 6M+8SM+4ST+32A (Cytotype C) and scanty heterochromatin, mainly located throughout pericentromeric regions of several chromosomal pairs. No homologies with the As-51 satellite DNA were observed in the three cytotypes, although all of them presented multiple 18S rDNA sites, as detected by both silver nitrate staining and FISH (fluorescent in situ hybridization). The application of the term "species complex" in Astyanax is discussed from a cytotaxonomic viewpoint. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Astyanax hastatus; Molecular cytogenetics; Karyotypic evolution; Species complex. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000300009 |
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| Cipriano,Roger Raupp; Fenocchio,Alberto Sérgio; Artoni,Roberto Ferreira; Molina,Wagner; Noleto,Rafael Bueno; Kantek,Daniel Luis Zanella; Cestari,Marta Margarete. |
| In this study, five species of marine fishes from the Paranaguá Bay in the Brazilian coast were evaluated. Eucinostomus argenteus and Diapterus rhombeus (Gerreidae) presented 48 chromosomes, all of which more acrocentric (FN = 48); Strongylura timucu and S. marina (Belonidae) also presented 48 chromosomes, but with a higher karyotypic complexity than the Gerreidae, 10M+2SM+36A (FN = 60) and 4M+44A (FN = 52), respectively. The fifth species, Mugil curema (Mugilidae), different than the others, presented only 28 chromosomes 20M+4ST+4A (FN = 48). The species presented diversity in the karyotypic macro-structure, which should be relevant for the cytotaxonomy and the evolution of this group of the vertebrate. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Marine fishes; Karyotype; Cytotaxonomy; Karyotypic evolution. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000200010 |
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| Alves,Lânia Isis F.; Lima,Saulo Antônio A.; Felix,Leonardo P.. |
| The chromosomes of 15 species of Iridaceae of the genera Alophia, Cipura, Eleutherine, Neomarica and Trimezia (subfamily Iridoideae) were examined after conventional Giemsa staining. The karyotypes of Alophia drummondii (2n = 14+1B, 28, 42 and 56), Cipura paludosa (2n = 14), C. xanthomelas (2n = 28) and Eleutherine bulbosa (2n = 12) were asymmetric; Neomarica candida, N. caerulea, N. humilis, N. glauca, N. gracilis, N. northiana and Neomarica sp. (2n = 18); N. cf. paradoxa (2n = 28), Trimezia fosteriana (2n = 52), T. martinicensis (2n = 54) and T. connata (2n = 82) were all generally symmetric. New diploid numbers of 2n = 56 for Alophia drummondii, 2n = 18 for N. candida, N. humilis, N. glauca, and N. gracilis, 2n = 28 for N. cf. paradoxa, and 2n = 82 for... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Iridaceae; Disploidy; Karyotypic evolution; Polyploidy; Asymmetrical karyotype. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000200016 |
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| Alves,José Carlos Pansonato; Paiva,Luiz Ricardo de Souza; Oliveira,Claudio; Foresti,Fausto. |
| Karyotypes of seven fish species of the genus Characidium, three of them studied for the first time, were characterized using conventional cytogenetic techniques (Giemsa staining, Ag-NOR, and C-banding). All species presented a diploid number of 2n=50, with only metacentric and submetacentric chromosomes, as observed in all Characidium species studied. In two species cells with one to three B chromosomes were observed. All species analyzed have a single NOR-bearing chromosome pair with morphological differences among them. Characidium cf. zebra shows heterochromatic blocks restricted to the pericentromeric regions of all chromosomes denoting the absence of a sex chromosome system. On the other hand, the species Characidium lanei, C. pterostictum, C.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotypic evolution; Sex chromosomes; B-chromosomes; Ag-NORs. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252010000100010 |
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