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.
The Blue Spring aphaostracon or Blue Spring hydrobe, scientific name Aphaostracon asthenes, is a species of minute freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Cochliopidae.
Cochliopa is a genus of freshwater snails, specifically cave snails, aquatic gastropod mollusks in the family Cochliopidae.
The Harney Basin duskysnail, scientific name Colligyrus depressus, is a species of freshwater snail, an aquatic gastropod mollusk in the family Hydrobiidae.
Colligyrus is a genus of small freshwater snails that have an operculum, aquatic gastropod mollusks in the family Hydrobiidae.
Fluminicola is a genus of minute freshwater snails with an operculum, aquatic gastropod molluscs or micromolluscs in the family Lithoglyphidae.
Pyrgulopsis is a genus of freshwater snails with a gill and an operculum, aquatic gastropod mollusks in the family Hydrobiidae.
The Crystal Spring springsnail, scientific name Pyrgulopsis crystalis, is a species of small freshwater snail, an aquatic gastropod mollusk in the family Hydrobiidae.
The sportingoods tryonia, scientific name Tryonia angulata, is a species of small freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Hydrobiidae. This species is endemic to the United States.
Brune's tryonia, scientific name Tryonia brunei, is a species of very small freshwater snail that has a gill and an operculum, an aquatic gastropod mollusks in the family Hydrobiidae. This species is endemic to the United States (Texas). It was formerly listed as Threatened in 1993/1994 and Data Deficient since 1996 until it was changed to Critically Endangered and possibly extinct in 2012; this is because it is found only in Phantom Lake, Balmorhea Lake, has range of less than 100 km², and was last observed in 1993. A 1991 report by the United States Fish and Wildlife Service also listed it as Endangered and they also later noted the unknown population. It is found in firm substratum and on mud before modification.
Cochliopidae is a family of small freshwater snails with gills and an operculum, aquatic gastropod mollusks.
Lithoglyphidae is a family of small freshwater snails with gills and an operculum, aquatic gastropod mollusks.
Heleobia is a genus of small freshwater and brackish water snails with a gill and an operculum, aquatic gastropod mollusks in the family Cochliopidae and the superfamily Truncatelloidea.
The Socorro springsnail, scientific name Pyrgulopsis neomexicana, is an endangered species of minute freshwater snail with a gill and an operculum, an aquatic gastropod mollusk or micromollusk in the family Hydrobiidae, the mud snails.
Stenothyridae is a family of small freshwater snails, snails with gills and an operculum, aquatic gastropod mollusks in the superfamily Truncatelloidea.
Eremopyprgus is a genus of very small freshwater snails, aquatic gastropod mollusks in the family Cochliopidae.
Pyrgulopsis aardahli, commonly known as the Benton Valley springsnail, is a species of freshwater snails in the family Hydrobiidae.
Minckleyella is a monotypic genus of gastropods belonging to the family Cochliopidae. The only species is Minckleyella balnearis.
