Hydrobiidae, commonly known as mud snails, is a large cosmopolitan family of very small freshwater and brackish water snails with an operculum; they are in the order Littorinimorpha.
Vertigo is a genus of minute, air-breathing land snails, terrestrial pulmonate gastropod molluscs or micromollusks in the family Vertiginidae, the whorl snails.
Oxychilus is a genus of small air-breathing land snails, terrestrial pulmonate gastropods in the subfamily Oxychilinae of the family Oxychilidae, the glass snails.
Bithynia is a genus of small freshwater snails with an operculum, aquatic prosobranch gastropod mollusks in the family Bithyniidae.
Viviparus, commonly known as the river snails, is a genus of large, freshwater snails with an operculum, aquatic gastropod molluscs.
Gyraulus is a genus of small, mostly air-breathing, freshwater snails, aquatic pulmonate gastropod mollusks in the family Planorbidae, the ram's horn snails.
The river limpet is a species of very small, freshwater, air-breathing limpet, an aquatic pulmonate gastropod mollusk in the tribe Ancylini within the family Planorbidae, the ram's horn snails and their allies.
Ferrissia is a genus of small, air-breathing freshwater limpets, aquatic gastropod mollusks in the family Planorbidae, the ram's horn snails and their allies.
Hydrobia is a genus of very small brackish water snails with a gill and an operculum, aquatic gastropod mollusks in the family Hydrobiidae.
Melanopsis is a genus of freshwater snails with a gill and an operculum, aquatic gastropod mollusks in the family Melanopsidae.
Pseudamnicola is a genus of small brackish water snails with an operculum, aquatic gastropod mollusks in the subfamily Pseudamnicolinae of the family Hydrobiidae.
Theodoxus is a genus of nerites, small water snails with an operculum, some of which live in freshwater, and some in both freshwater and brackish water, aquatic gastropod mollusks in the family Neritidae, the nerites.
Valvata is a genus of very small freshwater snails with an operculum, aquatic gastropod mollusks in the family Valvatidae, the valve snails.
Williamia is a genus of small sea snails or false limpets, marine pulmonate gastropod molluscs in the family Siphonariidae, the false (air-breathing) limpets.
Anisus is a genus of small air-breathing freshwater snails, aquatic pulmonate gastropod mollusks in the subfamily Planorbinae of the family Planorbidae, the ramshorn snails and their allies.
Acicula is a genus of very small land snails with an operculum, terrestrial gastropod mollusks in the family Aciculidae.
Truncatelloidea is a superfamily of snails, gastropod mollusks in the clade Caenogastropoda.
Potomida is a genus of bivalves belonging to the subfamily Gonideinae of the family Unionidae.
