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.
Alzoniella is a genus of minute freshwater spring snails, aquatic gastropod mollusks or micromollusks in the subfamily Islamiinae of 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.
Pseudamnicola is a genus of small brackish water snails with an operculum, aquatic gastropod mollusks in the subfamily Pseudamnicolinae of the family Hydrobiidae.
Alzoniella slovenica is a species of very small or minute freshwater snail with an operculum, an aquatic gastropod mollusk in the family Hydrobiidae, which are sometimes known as the snouted water snails.
Cochliopidae is a family of small freshwater snails with gills and an operculum, aquatic gastropod mollusks.
Mercuria is a genus of small brackish water snails or freshwater snails with a gill and an operculum, aquatic gastropod mollusks in the family Hydrobiidae.
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.
Navarriella elliptica is a species of very small aquatic snail, a spring snail, an operculate gastropod mollusc in the family Hydrobiidae.
Corrosella is a genus of minute freshwater snails with an operculum, aquatic gastropod molluscs or micromolluscs in the subfamily Pseudamnicolinae of the family Hydrobiidae.
Spiralix is a genus of very small aquatic snails, operculate gastropod mollusks in the family Moitessieriidae.
Alzoniella edmundi is a species of spring snail, an aquatic gastropod in the family Hydrobiidae.
Alzoniella junqua is a species of very small aquatic snail, a spring snail, an operculate gastropod mollusc in the family Hydrobiidae.
Alzoniella perrisii is a species of very small aquatic snail, a spring snail, an operculate gastropod mollusc in the family Hydrobiidae.
