Close genetic similarity among populations of the white croaker (Micropogonias furnieri) in the south and south-eastern Brazilian coast.

Abstract

Micropogonias furnieri (white croaker) is a demersal sciaenid species highly exploited along the south-eastern coast of South America. Off the Brazilian Coast some morphological and population dynamic characters suggested the presence of two partially isolated populations between 238S and 338S latitude. To study the white croaker population structure in this area, 17 enzyme and one protein-encoding loci were examined by starch and polyacrylamide gel electrophoresis in seven sampling sites for a total of 638 individuals. The allozyme results showed a high degree of genetic homogeneity in allele frequencies (Fstà0.005) and also high levels of gene Øow were found among the sampled populations. Therefore, the results do not support the hypothesis of the presence of two partially isolated populations of the white croaker in the studied area.