Ancylus is a genus of very small, freshwater, air-breathing limpets. They are aquatic pulmonate gastropod mollusks in the tribe Ancylini within the family Planorbidae, the ram's horn snails and their allies.
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.
Planorbis is a genus of air-breathing freshwater snails, aquatic pulmonate gastropod mollusks in the family Planorbidae, the ram's horn snails, or planorbids. All species in this genus have sinistral or left-coiling shells.
Bithyniidae is a family of small freshwater snails with an operculum, aquatic gastropod molluscs in the clade Littorinimorpha.
Valvatidae, the valve snails, is a taxonomic family of very small freshwater snails with an operculum, aquatic gastropod mollusks.
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 mollusks.
Gyraulus is a genus of small, mostly air-breathing, freshwater snails, aquatic pulmonate gastropod mollusks in the family Planorbidae, the ram's horn snails.
Radix is a genus of air-breathing freshwater snails, aquatic pulmonate gastropods in the family Lymnaeidae, the pond snails.
Bythinella is a genus of very small freshwater snails, an aquatic gastropod mollusk in the family Bythinellidae.
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.
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.
Segmentina is a genus of very small, air-breathing, freshwater snails, aquatic gastropod mollusks or micromollusks in the family Planorbidae, the ramshorn snails.
Tanousia is an extinct genus of freshwater snails with gills and an operculum, a gastropod mollusk in the family Lithoglyphidae.
Pyrgula is a genus of freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Hydrobiidae.
