''Margarya'' 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 large

operculate The operculum (; ) is a corneous or calcareous anatomical structure like a trapdoor that exists in many (but not all) groups of sea snails and freshwater snails, and also in a few groups of land snails; the structure is found in some marine and ...

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, 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

Viviparidae Viviparidae, sometimes known as the river snails or mystery snails, are a family of large operculate freshwater snails, aquatic gastropod mollusks. This family is classified in the informal group Architaenioglossa according to the taxonomy of ...

.Bouchet, P. (2014). Margarya G. Nevill, 1877. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=758767 on 2014-12-10

Taxonomy

The genus ''Margarya'' was described by Nevill (1877) based on shells of the type species collected by A.R. Margary from Lake Erhai, the type locality of ''

Margarya melanioides ''Margarya melanioides'' is a species of large operculate freshwater snail, an aquatic gastropod mollusk in the family Viviparidae, the river snails. ''Margarya melanioides'' is the type species of the genus ''Margarya''. Distribution The di ...

''. Based on shell and radular morphology, Tchang & Tsi (1949) revised this genus for the first time and recognized seven distinct species. He created two subgenera of ''Margarya'' , viz ''

Tchangmargarya ''Tchangmargarya'' is a genus of large operculate freshwater snails, aquatic gastropod mollusks in the family Viviparidae. Taxonomy ''Tchangmargarya'' originally was a subgenus of ''Margarya'', and is elevated to a full genus based on molecu ...

'' and ''Mabillemargarya''. The first molecular phylogeny showed that the genus ''Margarya'' is

polyphyletic A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of converg ...

and divided into three distinct clades. Combining study of comparative morphology and molecular phylogeny, Zhang ''et al''. revised the systematics of ''Margarya'' and recognized eight genuine extant species. However, only four species were found belonging to ''Margarya'' s. str., the rest species belonging to distinct genus ''

'' or ''

Anularya ''Anularya'' is a genus of large operculate freshwater snails, aquatic gastropod mollusks in the family Viviparidae. Distribution The extant species of this genus appear to be endemic to Fuxian Lake, Xingyun Lake, Qilu Lake, Datun Lake and ...

''.

Distribution

This genus appear to be endemic to

Dian Lake Dianchi Lake (), also known as Lake Dian and Kunming Lake (), is a large lake located on the Yunnan-Guizhou Plateau close to Kunming, Yunnan, China. Its nickname is the "Sparkling Pearl Embedded in a Highland" () and it was the model for the Kun ...

Erhai Lake Erhai or Er Lake (), is an alpine fault lake in Yunnan province, China. Erhai was also known as Yeyuze () or Kunming Lake () in ancient times. Etymology The character "洱" (er) does not have the same meaning as ear (耳). During the Han to Tang ...

Cibi Lake Cibi Lake () is a lake in Eryuan County, northwestern Yunnan Province, China. It lies about 73 km north of Dali City. It is fed by the Fengyu River and drains southward into the Erhai Lake via the Miju River Miju may refer to: * Miju langu ...

Jianhu Lake Jianhu County () is under the administration of Yancheng, Jiangsu province, China. It borders the prefecture-level cities of Huai'an and Yangzhou to the west. The main town in Jianhu is commonly just called Jianhu, and sometimes Huduo () or “Hu ...

Xihu Lake Xihu may refer to: Mainland China *West Lake (), Hangzhou, Zhejiang *Xihu District, Benxi (), Liaoning *Xihu District, Hangzhou (), Zhejiang *Xihu District, Nanchang (), Jiangxi * Xihu Township, Jiangxi ( zh; ), subdivision of Fuliang County, Jiang ...

, and

Lugu Lake Lugu Lake () is located in the northwest of the Yunnan plateau, with the middle of the lake forming the border between the Ninglang County of Yunnan Province and the Yanyuan County of Sichuan Province. The formation of the lake is thought to have ...

Yunnan Province Yunnan , () is a landlocked province in 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 Kunming. The province borders the C ...

in the

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 ...

Species

There are 4 extant species and 4 fossil species of ''Margarya'' s. str. ''

Margarya bicostata ''Margarya bicostata'' is a species of large operculate freshwater snail, an aquatic gastropod mollusk in the family Viviparidae, the river snails. Distribution The distribution of ''Margarya bicostata'' includes Fuxian Lake in Yunnan Provi ...

'' and '' Margarya mansuyi'' are transferred to ''

''. '' Margarya yangtsunghaiensis'' is transferred to ''

''. Species within the genus ''Margarya'' include 8 species: *(extant) '' Margarya francheti'' (Mabille, 1886) *(extant) ''

'' Nevill, 1877 - type species *(extant) '' Margarya monodi'' (Dautzenberg & Fischer, 1905) *(extant) '' Margarya oxytropoides'' (Heude, 1889)Heude P. M. (1882–1890). Notes sur les mollusques terrestres de la Vallée du Fleuve Bleu. ''Mémoires concernant l′histoire naturelle de l′Empire chinois'' 1: 1–188. *(fossil) '' Margarya spinicostata'' Li, 1987 *(fossil) '' Margarya angulata'' Li, 1987 *(fossil) '' Margarya nana'' Huang, 1986 *(fossil) '' Margarya nanningensis'' Tian, Fuersich & Schneider 2013 Species brought into synonymy: *''Margarya carinata'' (Neumayr, 1887): synonym of ''

'' Nevill, 1877 *''Vivipara delavayi'' (Mabille, 1886): synonym of ''

'' Nevill, 1877 *''Margarya tropidophora'' (Mabille, 1886): synonym of '' Margarya francheti'' (Mabille, 1886) *''Cipangopaludina dianchiensis'' Zhang, 1990: synonym of '' Margarya oxytropoides'' (Heude, 1889) *''Margarya melanioides dianchiensis'' Huang, 2007: synonym of '' Margarya oxytropoides'' (Heude, 1889) *''Margarya elongata'' Tchang & Tsi, 1949: synonym of '' Margarya monodi'' (Dautzenberg & H. Fischer, 1905) *''Margarya tchangsii'' Xia, 1982: synonym of '' Margarya monodi'' (Dautzenberg & H. Fischer, 1905) *''Margarya yangtsunghaiensis'' Tchang & Tsi, 1949: synonym of '' Tchangmargarya yangtsunghaiensis'' (Tchang & Tsi, 1949) *''Margarya yini'' (Tchang & Tsi, 1982): synonym of '' Margarya monodi'' (Dautzenberg & H. Fischer, 1905)

Cladogram

The cladogram 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 ...

and cytochrome-c oxidase I (COI), and nuclear

ITS2 Internal transcribed spacer (ITS) is the spacer DNA situated between the small-subunit ribosomal RNA (rRNA) and large-subunit rRNA genes in the chromosome or the corresponding transcribed region in the polycistronic rRNA precursor transcript. I ...

genes showing the phylogenic relationships of the genus ''Margarya'' indicates that ''Margarya'' is

. Margarya as traditionally delimited decayed into three distinct clades. The sister lineages of two of these clades are representatives from different viviparid genera, which are widely distributed in East and Southeast Asian rivers and lakes. These predominantly riparian viviparids also differ markedly in their shell morphology. Herein only genus-level phylogenic relationship is given, whereas relationship between lower taxonomic units deserve further study.

References

External links

Photo of ''Margarya melanoides'' with background of the lake
* Kobelt W. (1909). "Die Gattung ''Paludina'' Lam. (''Vivipara'' Montfort) (Neue Folge). In Abbildungen nach der Natur mit Beschreibungen". ''Systematisches Conchylien-Cabinet von Martini und Chemnitz'', Nürnberg, 1(21a): pp
97
430, plates 15-77.
page 187
193
table 37
39. * *Yen T. C. (1943). "A preliminary revision of the Recent species of Chinese Viviparidae". '' The Nautilus'' 56
124
130. {{Taxonbar, from=Q6122947 Viviparidae