# Pomatiopsidae

Pomatiopsidae is a family of small, mainly freshwater snails, (some also occur in other habitats) that have gills and an operculum, aquatic gastropod mollusks in the superfamily Truncatelloidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).
Pomatiopsidae are well known as intermediate hosts of Asian schistosomes.

## Distribution

Species in the family Pomatiopsidae occur worldwide. The generic diversity of Pomatiopsinae is particularly high in the Japanese Archipelago, where four of the eight genera, including two endemics, are recorded. The subfamily Triculinae radiated as aquatic snails in freshwater habitats in Southeast Asia.

## Description

The American malacologist William Stimpson first defined this taxon as Pomatiopsinae in 1865. Stimpson's diagnosis reads as follows:
   Pomatiopsinae, with the shell and operculum as in the Rissoinae. Foot with lateral sinuses. Size small. Amphibious. Genus Pomatiopsis, Tryon.

## Subfamilies

The family Pomatiopsidae consists of 2 subfamilies (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005) that follows classification by Davis (1979):
* Subfamily Pomatiopsinae Stimpson, 1865 - synonyms: Hemibiinae Heude, 1890; Tomichiinae Wenz, 1938; Coxiellidae Iredale, 1943; Oncomelaniidae Salisbury & Edwards, 1961; Cecininae Starobogatov, 1983
* Subfamily Triculinae Annandale, 1924
** tribe Triculuni Annandale, 1924 - synonym: Delavayidae Annandale, 1924
** tribe Jullieniini Davis, 1979
** tribe Lacunopsini Davis, 1979
** tribe Pachydrobiini Davis & Kang, 1990
Family-group name Rehderiellinae Brandt, 1974 is also in Pomatiopsidae, but it is not allocated in detail.

## Genera

Genera within the family Pomatiopsidae include:
* Spiripockia Simone, 2012 (not allocated to a subfamily)
Subfamily Pomatiopsinae
* Blanfordia Adams, 1863
* Cecina A. Adams, 1861
* Coxiella E. A. Smith, 1894: belongs in the family Tomichiidae
* Floridiscrobs Pilsbry and McGinty, 1949
* Fukuia Abbott & Hunter, 1949
* Hemibia Heude, 1890 (species type: Oncomelania hupensis Gredler, 1881
* Idiopyrgus Pilsbry, 1911 - synonym: Aquidauania Davis, 1979: belongs in the family Tomichiidae
* Oncomelania Gredler, 1881
* Pomatiopsis Tryon, 1862 - the type genus of the family Pomatiopsidae
* Tomichia Benson, 1851: belongs in the family Tomichiidae
Subfamily Triculinae - there are over 20 genera in Triculinae
tribe Triculuni
* Delavaya Heude, 1889
* Fenouilia Heude, 1889
* Lithoglyphopsis Thiele, 1928
* Tricula Benson, 1843 - type genus of the tribe Triculuni
tribe Jullieniini
* Hubendickia Brandt, 1968
* Hydrorissoia Bavay, 1895
* Jullienia Crosse & P. Fischer, 1876 - type genus of the tribe Jullieniini
* Karelainia Davis, 1979
* Kunmingia Davis & Kuo in Davis, 1981
* Neoprososthenia Davis & Kuo in Davis, Kuo, Hoagland, Chen, Yang & Chen, 1984
* Pachydrobiella Thiele, 1928 - with the only species Pachydrobiella brevis (Bavay, 1895)
* † Paraprososthenia Annandale, 1919
* Saduniella Brandt, 1970 - with the only species Saduniella planispira Brandt, 1970
tribe Lacunopsini
* Lacunopsis Deshayes, 1876 - type genus of the tribe Lacunopsini
tribe Pachydrobiini
* Gammatricula Davis & Liu in Davis, Liu & Chen, 1990
* Halewisia Davis, 1979 - with the only species Halewisia expansa (Brandt, 1970)
* Jinghongia Davis in Davis & Kang, 1990
* Neotricula Davis in Davis, Subba Rao & Hoagland, 1986
* Pachydrobia Crosse & P. Fischer, 1876 - type genus of the tribe Pachydrobiini
* Robertsiella Davis & Greer, 1980
* Wuconchona Kang, 1983
Rehderiellinae is not allocated to a subfamily
* Rehderiella Brandt, 1974 - type genus of the taxon Rehderiellinae

## Ecology

The Pomatiopsidae have various life habits: aquatic, amphibious, littoral, halophilic, cavernicolous and even terrestrial. Terrestrial taxa occur only on the Japanese Archipelago located in East Asia (Blanfordia). Tomichia and Coxiella include several halophilic species occurring on saline lakes.
Pomatiopsidae invaded freshwater habitats from marine ones in one or in two independent lineages. They also invaded terrestrial habitats from freshwater habitats in two independent lineages.
Overview of diversity and habitat of genera in Pomatiopsidae: :
| Genus | Number of species | Habitat |
| Blanfordia | 3 | terrestrial |
| Cecina | 8 | littoral of the sea |
| Coxiella | 10 (one of them extinct) | saline lakes |
| Fukuia | 3 | terrestrial and freshwater, amphibious, often arboreal |
| "Fukuia" ooyagii - unassigned to genus | 1 | freshwater |
| Hemibia | ?? | ?? |
| Idiopyrgus | 1-3 species | freshwater |
| Oncomelania | 2 | freshwater, marshy ground, seasonally amphibious |
| Pomatiopsis | 4 | marshy ground, amphibious |
| Tomichia | 11 | freshwater, brackish, saline lakes |
| Delavaya | ? | ? |
| Fenouilia | ? | freshwater |
| Lithoglyphopsis | ? | ? |
| Tricula | 15-20+ | freshwater |
| Hubendickia | 16 | ? |
| Hydrorissoia | 7 | ? |
| Jullienia | 10 | ? |
| Karelainia | 4 | ? |
| Kunmingia | ? | ? |
| Neoprososthenia | ? | ? |
| Pachydrobiella | 1 | ? |
| † Paraprososthenia | | fossil, freshwater lake beds |
| Saduniella | 1 | ? |
| Lacunopsis | 12 | ? |
| Gammatricula | 4 | ? |
| Halewisia | 1 | ? |
| Jinghongia | ? | ? |
| Neotricula | 2 (at least) | freshwater |
| Pachydrobia | 10 | ? |
| Robertsiella | 3 | freshwater, streams |
| Wuconchona | ? | ? |
| Rehderiella | ? | ? |
| Spiripockia | 1 | cavernicolous |