Genetic structure and demographic history of the endemic Mediterranean scallop Pecten jacobaeus inferred from mitochondrial 16s DNA sequence analysis

Understanding the genetic population structure of species going through population decline is primordial in implementing a management plan. In the case of Pecten jacobaeus, previous genetic studies have been limited to populations in the western Mediterranean (Spain) and the Adriatic Sea (Italy). To check the presence of phylogeographic breaks between the two Mediterranean basins, we scored the variability of the mitochondrial 16S rRNA gene in two populations from the eastern basin (Tunisia and Greece) and pooled them with those cited above. The two newly analyzed populations shared the most frequent haplotypes with the other populations and showed no evidence of phylogeographic breaks. We found lower levels of genetic variability in the Adriatic and the Aegean populations, but not in Tunisia, with respect to the Western Mediterranean. Significant differences in pooled haplotype frequencies indicated some genetic differentiation between the pooled Chioggia and Vouliagmeni populations and the other pooled populations.