 Two of the most common species are "Benedictia baicalensis" and "Megalovalvata baicalensis".Bivalve diversity is lower with more than 30 species; about half of these, all in the families Euglesidae, Pisidiidae, and Sphaeriidae, are endemic (the only other family in the lake is the Unionidae with a single nonendemic species).The endemic bivalves are mainly found in shallows, with few species from deep water.