Bithynia

Bithynia is a genus of small freshwater snails with an operculum, aquatic prosobranch gastropod mollusks in the family Bithyniidae. The diploid chromosome number of Bithynia sp. from Egypt is 2n=32. Distribution Lake Skadar with five species of Bithynia is a biodiversity hotspot of Bithynia evolution. Species Glöer (2002) recognized four subgenera Bithynia, Codiella, Neumayria and Parafossarulus within European species. He reassigned two European extinct species of Parafossarulus into a subgenus of the genus Bithynia, but the genus Parafossarulus is generally accepted for the Asian species. The subgenus Digoniostoma is also recognized for Asian species.