Genetic Variability of Manila Clam Venerupis philippinarum and its hybridization with native clam Venerupis decussata

Manila clam Venerupis philippinarum – synonym Ruditapes philippinarum (Adams and Reeve, 1850), family Veneridae – is a successful marine invader, being introduced worldwide for bivalve aquaculture and fisheries activities. In Europe, it has been introduced in the early ’70, nowadays representing one of the most important economic resource within European seafood products. Genetic diversity of introduced populations is poorly known, despite its economic value. Biogeography and population genetics of Manila clam has been investigated in 12 introduced Manila clam populations in Italy, Spain, and Portugal from Mediterranean and Atlantic sampling sites, by both 16SrDNA sequencing and microsatellite genotyping. Moreover, hybridization between alien clam and native clam Venerupis decussata – synonym Ruditapes decussata (Linnaeus, 1758) family Veneridae – has been investigated in Portuguese sympatric populations by nuclear genes genotyping (ITS1, ITS2, 5S).