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.
Belgrandiella is a genus of minute freshwater snails with a gill and an operculum, aquatic gastropod mollusks in the family Hydrobiidae.
Alzoniella pyrenaica is a species of minute freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Hydrobiidae. This species is endemic to France.
Bythinella is a genus of very small freshwater snails, an aquatic gastropod mollusk in the family Bythinellidae.
Moitessieria is a genus of minute freshwater snails with an operculum, aquatic gastropod molluscs or micromolluscs in the family Moitessieriidae.
Platyla is a genus of very small land snails with an operculum, terrestrial gastropod mollusks or micromollusks in the family Aciculidae.
Mercuria similis is a species of small freshwater snail with an operculum, an aquatic gastropod mollusk in the family Hydrobiidae.
Moitessieriidae is a family of small freshwater snails, aquatic gastropod molluscs in the superfamily Truncatelloidea.
Islamia is a genus of small freshwater snails with a gill and an operculum, aquatic gastropod mollusks in the family Hydrobiidae.
Alzoniella iberopyrenaica is a species of very small aquatic snail, a spring snail, an operculate gastropod mollusc in the family Hydrobiidae.
Alzoniella marianae is a species of very small aquatic snail, a spring snail, an operculate gastropod mollusc in the family Hydrobiidae.
Alzoniella pellitica is a species of very small aquatic snail, a spring snail, an operculate gastropod mollusc in the family Hydrobiidae.
Sardopaladilhia is a genus of very small aquatic snails, operculate gastropod mollusks in the family Moitessieriidae.
Terraconia is a genus of very small freshwater snails with an operculum, aquatic gastropod mollusks in the family Hydrobiidae.
Palaospeum is a genus of minute freshwater snails with an operculum, aquatic gastropod molluscs or micromolluscs in the family Moitessieriidae.
