Comparative cytogenetics among species of the Astyanax scabripinnis complex: evolutionary and biogeographical inferences
Genet. mol. biol
; 31(1,suppl): 173-179, 2008. ilus, tab
Article
em En
| LILACS
| ID: lil-484582
Biblioteca responsável:
BR26.1
ABSTRACT
Karyotype data are presented for distinct species of the genus Astyanax from four rivers belonging to three different hydrographic basins of the State of Paraná, Brazil (Verde River - Tibagi basin, Açungui River - Ribeira basin, and Santo Antônio and Jaguariaíva Rivers - Jaguariaíva basin). Three karyotypic forms were identified, here denominated karyotype A (2n = 50 chromosomes, with 8m+18sm+10st+14a, and thirteen 18S rDNA sites); karyotype B (2n = 50 chromosomes, with 8m+18sm+10st+1f4a, and four 18S rDNA sites); and karyotype C (2n = 48 chromosomes, with 10m+16sm+10st+12a, and eight 18S rDNA sites). The pattern of constitutive heterochromatin was similar among the three karyotypic forms, with few differences. The 5S rDNA corresponds to a synapomorphic character regarding its number and chromosomal localization. The karyotypic form A occurs in the distribution center of the type locality of A. paranae, in the proximities of the town of Castro (Tibagi basin), and may have reached the headwaters of the Ribeira River by the breakdown of geographical barriers. The karyotypic forms B and C are sympatric and syntopic, occurring solely in the Jaguariaíva River basin. Our hypothesis is that the karyotypic form A corresponds to the species A. paranae and forms B and C correspond to other species of the A. scabripinnis complex.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
LILACS
Assunto principal:
DNA Ribossômico
/
Citogenética
/
Peixes
Limite:
Animals
Idioma:
En
Revista:
Genet. mol. biol
Assunto da revista:
GENETICA
Ano de publicação:
2008
Tipo de documento:
Article
/
Project document
País de afiliação:
Brasil