Molecular genetics as a tool for fisheries management in the Brazilian Amazon: Piraíba (Brachyplatystoma filamentosum and Brachyplatystoma capapretum) (Siluriformes: Pimelodidae) in white-water rivers

Abstract

Specimens from two fish species commonly known as piraíba (Brachyplatystoma filamentosum and Brachyplatystoma capapretum) were sampled from fish landings in nine white-water river channel regions of the Brazilian Amazon. We genetically characterized these specimens, through sequencing of the mitochondrial DNA control region. Of the 337 samples collected, 66.77% belonged to B. filamentosum, while the remaining 33.23% belonged to B. capapretum. For both species, the haplotype diversity (Hd) values were high (>0.95). However, the nucleotide diversity (π) was higher in B. filamentosum (0.0118) than in B. capapretum (0.0041). We compared these values with the nucleotide diversity values of the control regions of other Amazonian fish species being overexploited or at risk of overexploitation.