Pachychilidae, common name pachychilids, is a

taxonomic Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

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 ...

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 ...

mollusc 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 esti ...

s in the

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

Sorbeoconcha Sorbeoconcha is a taxonomic clade of snails, i.e. gastropods, mainly marine species with gills and opercula, within the clade Caenogastropoda. The taxon Sorbeoconcha was named by Winston Ponder and David R. Lindberg in 1997. Taxonomy 1 ...

.Gofas, S. (2014). Pachychilidae. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=411651 on 2014-11-20

Distribution

Pachychilids are

s with a worldwide distribution in the tropics. Representatives are found in

South South is one of the cardinal directions or Points of the compass, compass points. The direction is the opposite of north and is perpendicular to both east and west. Etymology The word ''south'' comes from Old English ''sūþ'', from earlier Pro ...

and

Central America Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

, South and South-east

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...

and tropical

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

(

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

Torres Strait Islands The Torres Strait Islands are a group of at least 274 small islands in the Torres Strait, a waterway separating far northern continental Australia's Cape York Peninsula and the island of New Guinea. They span an area of , but their total land ...

Description

Pachychilids have an operculum, which is concentric and multispiral.

Ecology

All species in the family inhabit freshwater except '' Faunus ater'', which is a

brackish water Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estua ...

snail found in estuaries and other coastal habitats. Pachychilids are either

oviparous Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and ...

(lay eggs),

ovoviviparous Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a term used as a "bridging" form of reproduction between egg-laying oviparous and live-bearing viviparous reproduction. Ovoviviparous animals possess embryos that develop insi ...

viviparous Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the m ...

(retain developing eggs and youngs in special incubatory structures).

Notes on the taxonomy

The name is derived from a combination of the words 'pachy' (Greek = thick) and the suffix '-chilus' (Greek = Lip), meaning 'thick lipped' - with respect to the thickened aperture of the shell in some species. Most 20th-century authors did not recognize Pachychilidae as an independent family, but affiliated species under different groups, such as

Thiaridae Thiaridae, common name thiarids or trumpet snails, is a family of tropical freshwater snails with an operculum, aquatic gastropod mollusks in the superfamily Cerithioidea. MolluscaBase eds. (2021). MolluscaBase. Thiaridae Gill, 1871 (1823). A ...

and

Pleuroceridae Pleuroceridae, common name pleurocerids, is a family of small to medium-sized freshwater snails, aquatic gilled gastropod mollusks in the superfamily Cerithioidea.These snails have an operculum and typically a robust high-spired shell. Reprodu ...

. However, recent revisions based on molecular and morphological evidence have proven their independent and distinct status from the former. This family has no subfamilies (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).

Genera

Genera within the family Pachychilidae include: * † '' Bellatara'' Strand, 1928 - with only one species '' Bellatara janus'' (Mayer, 1870)Gofas, S. (2015). Pachychilidae P. Fischer & Crosse, 1892. In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=411651 on 2015-10-09 * '' Brotia'' H. Adams, 1866 * '' Doryssa'' Swainson, 1840 * † '' Eginea'' Pacaud & Harzhauser, 2012 * ''Faunus'' de Montfort, 1810 with the only species '' Faunus ater'' (

Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

1758 Events January–March * January 1 – Swedish biologist Carl Linnaeus (Carl von Linné) publishes in Stockholm the first volume (''Animalia'') of the 10th edition of Systema Naturae, 10th edition of ''Systema Naturae'', the sta ...

) * ''

Jagora ''Jagora'' is a genus of freshwater snails which have an operculum, aquatic gastropod mollusks in the family Pachychilidae. Distribution This genus is endemic to the Philippines. Species Species within the genus ''Jagora'' include: * '' ...

'' Köhler & Glaubrecht, 2003 * † '' Jponsia'' Pacaud & Harzhauser, 2012 * '' Madagasikara'' Köhler & Glaubrecht, 2010 - synonym: ''

Melanatria ''Madagasikara'' is a genus of tropical freshwater snails with an operculum (gastropod), operculum, aquatic animal, aquatic gastropod molluscs in the family (biology), family Pachychilidae. The Genus, generic name ''Madagasikara'' is from the M ...

'' Bowdich, 1822 auctt.Köhler F. & Glaubrecht M. (2010). "Uncovering an overlooked radiation: molecular phylogeny and biogeography of Madagascar’s endemic river snails (Caenogastropoda: Pachychilidae: ''Madagasikara'' gen. nov.). ''

Biological Journal of the Linnean Society The ''Biological Journal of the Linnean Society'' is a direct descendant of the oldest biological journal in the world, the ''Transactions of the Linnean Society''. It succeeded the earlier title in 1969. The journal specializes in evolution, and ...

'' 99: 867-894. . * † '' Nodifaunus'' Olsson, 1944 * ''

Pachychilus ''Pachychilus'', common name the jute snails, is a genus of freshwater snails with an operculum, aquatic gastropod mollusk in the family Pachychilidae. ''Pachychilus'' is the type genus of the family Pachychilidae. Distribution The distri ...

'' I. Lea & H. C. Lea, 1851 - type genus of the family Pachychilidae * '' Paracrostoma'' Cossmann, 1900 * '' Potadoma'' Swainson, 1840 * † '' Pseudobellardia'' Cox, 1931 * ''

Pseudopotamis ''Pseudopotamis'' is a genus of freshwater snails which have an operculum, aquatic gastropod mollusks in the family Pachychilidae. Distribution It occurs on the Torres Strait Islands. A sister group (the closest relative) of ''Pseudopota ...

'' Martens, 1894 * '' Sulcospira'' Troschel, 1858 - synonym: ''Adamietta'' Brandt, 1974 * † '' Tinnyea'' Hantken, 1887 * ''

Tylomelania ''Tylomelania'' is a genus of freshwater snails which have an operculum, aquatic gastropod mollusks in the family Pachychilidae. In the aquarium hobby, snails from this genus are commonly known as "rabbit snails" (not to be confused with sea ...

'' Sarasin & Sarasin, 1897von Rintelen T. & Glaubrecht M. (2005). "Anatomy of an adaptive radiation: a unique reproductive strategy in the endemic freshwater gastropod ''Tylomelania'' (Cerithioidea: Pachychilidae) on Sulawesi, Indonesia and its biogeographical implications." ''

'' 85: 513–542. . * † '' Wingeastonia'' K. Martin, 1906 ;Genera brought into synonymy: * ''Acrostoma'' Brot, 1871: synonym of '' Paracrostoma'' Cossmann, 1900 * ''Antimelania'' P. Fischer & Crosse, 1892: synonym of '' Brotia'' H. Adams, 1866 * ''Brotella'' Rovereto, 1899: synonym of '' Paracrostoma'' Cossmann, 1900 * Fauninae Cossmann, 1909 (subfamily) : synonym of ''Pachychilidae'' P. Fischer & Crosse, 1892 * ''Melanatria'' Bowdich, 1822: synonym of ''

Faunus In ancient Roman religion and myth, Faunus was the rustic god of the forest, plains and fields; when he made cattle fertile he was called Inuus. He came to be equated in literature with the Greek god Pan, after which Romans depicted him as a ...

'' Montfort, 1810 * ''Oxymelania'' Crosse & P. Fischer, 1892: synonym of ''

'' I. Lea & H. C. Lea, 1851 * ''Pirena'' Lamarck, 1822: synonym of ''

'' Montfort, 1810 * ''Sphaeromelania'' Rovereto, 1899: synonym of ''

'' I. Lea & H. C. Lea, 1851 * ''Wanga'' Chen, 1943: synonym of '' Brotia'' H. Adams, 1866

Cladogram

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ...

based on sequences of mitochondrial

16S ribosomal RNA 16 S ribosomal RNA (or 16 S rRNA) is the RNA component of the 30S subunit of a prokaryotic ribosome (SSU rRNA). It binds to the Shine-Dalgarno sequence and provides most of the SSU structure. The genes coding for it are referred to as 16S rRNA ...

sequences showing phylogenic relations of Pachychilidae:

References

External links

* {{Taxonbar, from=Q2045444 Gastropod families