Viviparus

Viviparus, commonly known as the river snails, is a genus of large, freshwater snails with an operculum, aquatic gastropod molluscs.

[2] They are primitive members of the clade Caenogastropoda.

This genus is palaearctic in distribution,[3] and is known from the Jurassic to the Recent.

[4] Viviparus belongs to the subfamily Viviparinae.

Its taxonomy is currently under development and many of its species are often included in other related genera.