Data/hora: 11/06/2024 16:28:30

Provedor de dados: | 83
País: | Brazil
Título: | Diversity and chromosomal evolution in the genusAncistrusKner, 1854 (Loricariidae: Ancistrini) from three hydrographic basins of Mato Grosso State, Brazil
Autores: | Mariotto,Sandra; Centofante,Liano; Moreira-Filho,Orlando.
Data: | 2013-03-01
Ano: | 2013
Palavras-chave: | AgNOR; Cytogenetic; Diploid number; Heterochromatin.
Resumo: | Cytogenetic analyses were carried out in 117 specimens of seven species of the genus Ancistrus from three hydrographic in Mato Grosso State: Paraguay, Araguaia-Tocantins and Amazon basins. Conventional cytogenetic techniques were used to obtain mitotic chromosomes. C-banding was performed to detect heterochromatic regions and silver nitrate staining was used to identify nucleolar organizer regions (Ag-NORs). The counted and paired chromosomes revealed diploid numbers ranging from 2n = 40 to 2n = 54 with karyotype formulae varying from FN = 80 to FN = 86. Single marks in distinct chromosomes identified the nucleolar organizer regions. The constitutive heterochromatin was scarce in the diploid number from 2n = 50 to 2n = 54 and conspicuous blocks were observed in a single species with 2n = 40 chromosomes. These data corroborate the hypotheses of reduction of diploid number in species with derived features such as presence of sex chromosomes and polymorphisms, besides allowing inferences about the evolutionary mechanisms and the ancestor karyotype that favored the diversification of this important genus in the tribe Ancistrini.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000100125
Editor: | Sociedade Brasileira de Ictiologia
Relação: | 10.1590/S1679-62252013000100015
Formato: | text/html
Fonte: | Neotropical Ichthyology  v.11 n.1 2013
Fonte: | info:eu-repo/semantics/openAccess