CYTOGENETIC AND DNA CONTENT IN 6 GENERA OF THE FAMILY CALLICHTHYIDAE (PISCES, SILURIFORMES)
Nenhuma Miniatura disponível
Data
1993-04-01
Autores
Oliveira, C.
Almeidatoledo, L. F.
Mori, L.
Toledo, S. A.
Título da Revista
ISSN da Revista
Título de Volume
Editor
Univ Florence Botany Inst
Resumo
Cytogenetic studies involving conventional Giemsa staining, C-banding analysis and silver staining of NORs were performed on nine species belonging to six genera of the family Callichthyidae. The diploid number ranged from 2n = 44 to 2n = 100, the number of chromosomal pairs with NORs ranged from 1 to 4 and constitutive heterochromatin was mainly distributed in the centromeric and/or pericentromeric position of the chromosomes. The DNA content of erythrocytes from six species studied ranged from 1.18 +/- 0.07 to 2.77 +/- 0.22 pg/nucleus. The extensive variability in karyotypes and in nuclear DNA content detected are in accordance with the initial hypothesis that chromosome rearrangements and polyploidy have played a significant role in the evolutionary history of Callichthyidae.
Descrição
Palavras-chave
CALLICHTHYIDAE, KARYOTYPE, NOR, C-BAND, DNA CONTENT
Como citar
Caryologia. Florence: Univ Florence Botany Inst, v. 46, n. 2-3, p. 171-188, 1993.