''Erhaia'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of small to minute

freshwater snail Freshwater snails are gastropod mollusks which live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs ...

s with a

gill A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

and an operculum, aquatic

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

s in the family

Amnicolidae Amnicolidae is a family of small freshwater snails with a gill and an operculum, aquatic gastropod mollusks in the superfamily Rissooidea. This family is in the clade Littorinimorpha (according to the taxonomy of the Gastropoda by Bouchet & R ...

. ''Erhaia'' is the

type genus In biological taxonomy, the type genus is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearing type of a nominal f ...

of the tribe Erhaiini, which is now a synonym of the subfamily Amnicolinae. ''Erhaia'' (also within the tribe Erhaiini) was originally described as a genus within the

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 ...

in 1985, but Wilke et al. (2000, 2001) moved it to the Amnicolidae.Wilke T., Davis G. M., Gong X. & Liu H.-X. (2000). "''Erhaia'' (Gastropoda: Rissooidea): phylogenetic relationships and the question of ''Paragonimus'' coevolution in Asia". ''

American Journal of Tropical Medicine and Hygiene The American Society of Tropical Medicine and Hygiene (ASTMH) is an Arlington, Virginia-based non-profit organization of scientists, clinicians, students and program professionals whose longstanding mission is to promote global health through the ...

'' 62(4): 453-459
abstractPDF
Wilke T., Davis G. M., Falniowski A., Giusti F., Bodon M. & Szarowska M. (2001). "Molecular systematics of Hydrobiidae (Mollusca: Gastropoda: Rissooidea): testing monophyly and phylogenetic relationships". ''

Proceedings of the Academy of Natural Sciences of Philadelphia The ''Proceedings of the Academy of Natural Sciences of Philadelphia'' is a peer-reviewed scientific journal published by Academy of Natural Sciences of Drexel University The Academy of Natural Sciences of Drexel University, formerly the Academ ...

'' 151: 1-2
JSTOR

Distribution

The distribution of ''Erhaia'' includes southern

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...

and

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

. The center of biodiversity of ''Erhaia'' in China is located in the provinces of

Hunan Hunan (, ; ) is a landlocked province of the People's Republic of China, part of the South Central China region. Located in the middle reaches of the Yangtze watershed, it borders the province-level divisions of Hubei to the north, Jiangxi to ...

Hubei Hubei (; ; alternately Hupeh) is a landlocked province of the People's Republic of China, and is part of the Central China region. The name of the province means "north of the lake", referring to its position north of Dongting Lake. The prov ...

and

Sichuan Sichuan (; zh, c=, labels=no, ; zh, p=Sìchuān; alternatively romanized as Szechuan or Szechwan; formerly also referred to as "West China" or "Western China" by Protestant missions) is a province in Southwest China occupying most of the ...

. Distribution also includes Fujian Province. There is also scattered occurrences of ''Erhaia'' in

Yunnan Yunnan , () is a landlocked Provinces of China, province in Southwest China, the southwest of the People's Republic of China. The province spans approximately and has a population of 48.3 million (as of 2018). The capital of the province is ...

Province. These snails live in the

Yangtze River The Yangtze or Yangzi ( or ; ) is the longest list of rivers of Asia, river in Asia, the list of rivers by length, third-longest in the world, and the longest in the world to flow entirely within one country. It rises at Jari Hill in th ...

drainage and in the

Mekong River The Mekong or Mekong River is a trans-boundary river in East Asia and Southeast Asia. It is the world's twelfth longest river and the third longest in Asia. Its estimated length is , and it drains an area of , discharging of water annuall ...

drainage (1 species).

Description

The length of the

shell Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses ** Thin-shell structure Science Biology * Seashell, a hard ou ...

of this species is up to 3.9 mm.

Species

Species within the genus ''Erhaia'' include: * ''

Erhaia daliensis ''Erhaia'' is a genus of small to minute freshwater snails with a gill and an operculum, aquatic gastropod mollusks in the family Amnicolidae. ''Erhaia'' is the type genus of the tribe Erhaiini, which is now a synonym of the subfamily Amnic ...

'' Davis & Kuo, 1985 * ''

Erhaia gongjianguoi ''Erhaia'' is a genus of small to minute freshwater snails with a gill and an operculum, aquatic gastropod mollusks in the family Amnicolidae. ''Erhaia'' is the type genus of the tribe Erhaiini, which is now a synonym of the subfamily Amnic ...

'' (Kang, 1983) * '' Erhaia hubiensis'' (Liu, Zhang & Wang, 1983) * '' Erhaia jianouensis'' (Liu & Zhang, 1979) * '' Erhaia kunmingensis'' Davis & Kuo, 1985 * ''

Erhaia lii ''Erhaia'' is a genus of small to minute freshwater snails with a gill and an operculum, aquatic gastropod mollusks in the family Amnicolidae. ''Erhaia'' is the type genus of the tribe Erhaiini, which is now a synonym of the subfamily Amnic ...

'' (Kang) * '' Erhaia nainitalensis'' Davis & Rao, 1997Davis G. M. & Rao S. (1997). "Discovery of ''Erhaia'' (Gastropoda: Pomatiopsidae) in northern India with description of a new genus of Erhaiini from China". ''

'' 48: 273-299
JSTOR
* '' Erhaia robusta'' (Kang, 1986) * '' Erhaia sheminensis'' * '' Erhaia wangchuki'' Gittenberger, Sherub & Stelbrink, 2017 * ''

Erhaia wantanensis ''Erhaia'' is a genus of small to minute freshwater snails with a gill and an operculum, aquatic gastropod mollusks in the family Amnicolidae. ''Erhaia'' is the type genus of the tribe Erhaiini, which is now a synonym of the subfamily Amnic ...

'' * '' Erhaia wufengensis'' Synonyms: * ''Erhaia chinensis'' Davis et al. 1985 and ''Erhaia chinensis'' Davis & Kang, 1995Davis G. M. & Kang Z. B. (1995). "Advances in the Systematics of ''Erhaia'' (Gastropoda: Pomatiopsidae) from the People's Republic of China". ''

'' 146: 391-427
JSTOR
are synonyms of '' Chencuia chinensis'' Liu & Zhang, 1979

Ecology

''Erhaia'' lives in streams in mountainous areas.

References

{{Taxonbar, from=Q5385852 Amnicolidae