Astyanax;
Characidae;
Chapada Diamantina;
Paraguacu River;
population structure;
D O I:
10.1590/S1516-89132008000100013
中图分类号:
Q [生物科学];
学科分类号:
07 ;
0710 ;
09 ;
摘要:
The fishes of the family Characidae are among the main species of fresh water fishes in South America. In this work, some aspects of the population structure of two Astyanax species were assessed. The fishes were caught in Santo Antonio and Sao Jose rivers, in the Paraguacu basin, by standardized monthly samplings adapted to the microhabitats. Astyanax sp. b ( Sao Jose river) presented larger size than Astyanax sp. a ( Santo Antonio river). The length-weight relationship showed positive allometric growth for Astyanax sp. a, and negative for Astyanax sp. b. Both the species showed a long reproductive period, with higher activities in dry period.