Cytotaxonomy, heterochromatic polymorphism and natural triploidy of a species of Astyanax (Pisces, Characidae) endemic to the Iguaçu river basin

Brazilian Archives of Biology and Technology

Daniel Luis Zanella Kantek²  Rafael Bueno Noleto²  Alberto Sérgio Fenocchio¹  Marta Margarete Cestari² 

[1] ,Universidade Federal do Paraná Laboratório de Citogenética Animal Curitiba PR ,Brasil

关键词: Cytogenetics;    triploidy;    paracentric inversion;   

DOI  :  10.1590/S1516-89132007000100008

来源: SciELO

【 摘 要 】

Cytogenetic analysis with Astyanax sp. D revealed a karyotype of 2n=50 with 2M+26SM+6ST+16A, besides a triploid specimen showing 2n=75 chromosomes (3M+39SM+9ST+24A). C-banding strongly stained the terminal regions of several SM-ST-A chromossomes. Two pairs of acrocentric chromosomes presented interstitial heterochromatin, this state being polymorphic and occuring due to possible paracentric inversions. The results obtained with the AluI restriction enzyme and A3 chromomycin were similar to the C-banding. Relationships were proposed between Astyanax sp. D and A. scabripinnis, as well as considerations for a possible origin of the triploid specimen (2n=3x=75). When comparing the present results with cytogenetic features of other endemic Astyanax species in the Iguaçu river (A. sp. B and C), a clear differentiation was observed between them, indicating cytogenetics as an important cytotaxonomic tool.

【 授权许可】

CC BY-NC   
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