Hemisinidae

species of mollusc

species of mollusc

species of mollusc

Aylacostoma is a genus of tropical freshwater snails with an operculum. They are part of the family Hemisinidae, a group of aquatic gastropod molluscs. They are found in South and Central America. As a consequence of the Yacyretá Dam, two species are entirely extinct and another is extinct in the wild.

Hemisinidae is a family of snails in the superfamily Cerithioidea. They occur in freshwater and brackish environments on all continents except Australia and Antarctica.