Astyanax hastatus Myers, 1928 (Teleostei, Characidae): a new species complex within the genus Astyanax?

Genetics and Molecular Biology

Rubens Pazza¹  Karine Frehner Kavalco¹  Karina de Oliveira Brandão²  Lurdes Foresti de Almeida-Toledo² 

[1] Universidade Federal de Viçosa;Universidade de São Paulo;

关键词: Astyanax hastatus;    molecular cytogenetics;    karyotypic evolution;    species complex;   

DOI  :  10.1590/S1415-47572009005000055

来源: DOAJ

【 摘 要 】

Four populations of Astyanax hastatus Myers 1928 from the Guapimirim River basin (Rio de Janeiro State) were analyzed and three distinct cytotypes identified. These cytotypes presented 2n = 50 chromosomes, with 4M+8SM+10ST+28A (Cytotype A), 8M+10SM+14ST+18A (Cytotype B), 6M+8SM+4ST+32A (Cytotype C) and scanty heterochromatin, mainly located throughout pericentromeric regions of several chromosomal pairs. No homologies with the As-51 satellite DNA were observed in the three cytotypes, although all of them presented multiple 18S rDNA sites, as detected by both silver nitrate staining and FISH (fluorescent in situ hybridization). The application of the term "species complex" in Astyanax is discussed from a cytotaxonomic viewpoint.

【 授权许可】

Unknown