a b s t r a c t Pristis perotteti, the largetooth sawsh, is one of most endangered elasmobranchs because of sheries and habitat degradation. Its commercialization in Brazil is prohibited, but fresh or salted llets of this sh can be found in markets, labeled as "sharks". In this study we performed genetic analyses on "shark" samples from two important shery-trading ports in northern Brazil (Vigia and Bragança). Based on partial DNA sequences of the mitochondrial 16S and Cyt b genes, 24 (55%) out of 44 samples were un-equivocally identied as P. perotteti while the others comprised eight species of the families Carch-arhinidae and Ginglymostomatidae. These results show that shing surveillance and monitoring have not been effective to prohibit the commercialization of this highly endangered species. Published by Elsevier Ltd.