O cariótipo de uma população de Astyanax bimaculatus (Lannaeus,1758) coletada na Bacia Hidrográfica do Rio Piranhas -PB: uma análise biogeográfica.

Abstract

Cytogenetic studies within Neotropical ichthyofauna has been improving our knowledge about evolutionary changes occurring in the karyotype of species in natural conditions. This paper aims to characterize the karyotype of Astyanax bimaculatus fish population, collected in the Piranhas River basin, located in the municipality of Cajazeiras - PB. All animals were subjected to cytogenetic analysis after mitosis increase in hematopoietic tissues. The metaphasic chromosomes preparation were performed by "air drying” technique of cells from kidney. Afterwards slides were stained by Giemsa and metaphasic chromosomes were assembly according to the metacentric, submetacentric, subtelocentric and telocentric classification. The karyotype collected in the Piranhas River basin was performed by 06 metacentric, 20 submetacentric, 18 subtelocentric and 06 telocentric chromosomes (6m+20sm+18st+6t). This karyotype was similar to that recorded by Cunha (2014) in southeastern Brazilian watersheds.