Abstract
A molecular genetic analysis of freshwater unionid mussels collected in the Sagamigawa River (near Lake Sagami in northern Kanagawa Prefecture in central Japan) revealed that four of the mussels were Beringiana fukuharai. This is the first record of this species in this river basin. Morphological analyses were performed on the four adult specimens and the larvae they produced, and the results were compared with those of other congeneric species reported previously.