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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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| Prestes,Anahiê Bortoncello; Nardelli,Aline; Paiz,Leonardo Marcel; Gavazzoni,Mariane; Margarido,Vladimir Pavan. |
| ABSTRACT Bryconamericus is a highly diverse group of characid fishes, being cytogenetic a valuable tool for the delimitation of species. Bryconamericus aff. iheringii (Upper Uruguay/Lower Paraná), B. coeruleus (Upper Paraná), B. cf. ecai e B. cf. eigenmanni (Upper Uruguay) were studied cytogenetically, and presented 2n=52 chromosomes, with interpopulational/interspecific variation of karyotype and fundamental number. Heterochromatin was evidenced in pericentromeric, telomeric and interstitial regions, and it was shown to be an important cytogenetic marker. Single nucleolar organizing regions (NORs) were found in B. cf. eigenmanni, B. cf. ecai and B. aff. iheringii (Lower Paraná), and multiple in B. aff. iheringii (Upper Uruguay) and B. coeruleus, with... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome rearrangements; Co-localization; Cytotaxonomy; Cytosystematics; Intra and interspecific variation; Ribosomal genes. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252019000300203 |
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| Fernandes,Carlos Alexandre; Aguiar,Allan Kardec Moreira de; Paiz,Leonardo Marcel; Baumgärtner,Lucas; Piscor,Diovani; Margarido,Vladimir Pavan. |
| ABSTRACT Gymnorhamphichthys britskii is a Neotropical electric fish of family Rhamphichthyidae described from the Paraná-Paraguay system. This study reports the first karyotypic description of G. britskii collected from the upper Paraná river basin, which presented 2n=38 chromosomes, karyotype composed of 14 metacentric, 8 submetacentric, 2 subtelocentric and 14 acrocentric chromosomes, and fundamental number as 62 for both sexes. Heteromorphic sex chromosomes were absent. A single pair of nucleolar organizing regions (NORs) was detected in the submetacentric chromosome pair number 9 by silver staining and confirmed by the 18S rDNA probe. The 5S rDNA was located in a single chromosome pair. Heterochromatic regions were clearly observed in the short arms of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ag-NORs; C-banding; Fish cytogenetics; Karyotype evolution; Repetitive sequences. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252019000300205 |
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