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.
Sphaerium is a genus of very small freshwater clams, aquatic bivalve molluscs in the family Sphaeriidae, known as the fingernail clams. The small clams in this genus are unusual in that many of them, such as Sphaerium corneum, can climb around underwater on aquatic plants, using their long and strong foot.
Neritidae, common name the nerites, is a taxonomic family of small to medium-sized saltwater and freshwater snails which have a gill and a distinctive operculum. The family Neritidae includes marine genera such as Nerita, marine and freshwater genera such as Neritina, and freshwater and brackish water genera such as Theodoxus.
Pisidium is a genus of very small or minute freshwater clams known as pill clams or pea clams, aquatic bivalve molluscs in the family Sphaeriidae, the pea clams and fingernail clams.
Bithynia is a genus of small freshwater snails with an operculum, aquatic prosobranch gastropod mollusks in the family Bithyniidae.
Lymnaea is a genus of small to large-sized air-breathing freshwater snails, aquatic pulmonate gastropod mollusks in the subfamily Lymnaeinae ( of the family Lymnaeidae, the pond snails.
Viviparus, common name 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.
Melanoides is a genus of freshwater snail with an operculum, an aquatic gastropod mollusk in the subfamily Thiarinae of the family Thiaridae.
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.
Melanopsidae, common name melanopsids, is a family of freshwater gastropods in the clade Sorbeoconcha. Species in this family are native to southern and eastern Europe, northern Africa, parts of the Middle East, New Zealand, and freshwater streams of some large South Pacific islands.
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.
Azeca is a European genus of small air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Cochlicopidae.
Segmentina is a genus of very small, air-breathing, freshwater snails, aquatic gastropod mollusks or micromollusks in the family Planorbidae, the ramshorn snails.
Parafossarulus is a genus of freshwater snails with gills and an operculum, an aquatic prosobranch gastropod mollusks in the family Bithyniidae.
Truncatelloidea is a superfamily of snails, gastropod mollusks in the clade Caenogastropoda.
Choanomphalus 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.
Laevicaspia is a genus of gastropods belonging to the family Hydrobiidae.
Horatia is a genus of gastropod molluscs, comprising a small group of minute stygobiont freshwater snails with valvatoid shells, belonging to the subfamily Horatiinae of the family Hydrobiidae.
