''Cremnoconchus'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of small

freshwater snail Freshwater snails are gastropod mollusks that 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 t ...

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

s in the otherwise marine

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Littorinidae The Littorinidae are a taxonomic family of over 200 species of sea snails, marine gastropod molluscs in the clade Littorinimorpha, commonly known as periwinkles and found worldwide. Names In English-speaking countries, gastropod molluscs from ...

, the winkles or periwinkles.Strong E. E., Gargominy O., Ponder W. F. & Bouchet P. (2008). "Global Diversity of Gastropods (Gastropoda; Mollusca) in Freshwater". '' Hydrobiologia'' 595: 149-166
hdl.handle.net
. The generic name ''Cremnoconchus'' is from the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

word κρημνός which means

precipice In geography and geology, a cliff or rock face is an area of rock which has a general angle defined by the vertical, or nearly vertical. Cliffs are formed by the processes of weathering and erosion, with the effect of gravity. Cliffs are co ...

and from the

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

word κόγχος which means shell. This is the only freshwater genus within the Littorinidae; all other genera belonging to the family are marine. Molecular dating based on fossil records showed that ''Cremnoconchus'' separated from their last marine ancestor around 90 million years ago and have since diversified within the Indian sub-continent. Based on this time of split, it has been postulated that either break-up of

Gondwana Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zea ...

or fluctuating sea levels might have facilitated their diversification. Based on the current distribution of the closest relatives of ''Cremnoconchus,'' a Gondwanan origin is highly likely. Cremnoconchus map

The genus ''Cremnoconchus'' is endemic to the Western Ghats of

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

. All ''Cremnoconchus'' species live in spray zones of

waterfall A waterfall is any point in a river or stream where water flows over a vertical drop or a series of steep drops. Waterfalls also occur where meltwater drops over the edge of a tabular iceberg or ice shelf. Waterfalls can be formed in seve ...

s i.e., not directly under the heavy flow of the water. Most species are restricted to one waterfall, earning them the title of ''point endemic''. Very high footfall of tourists in the waterfalls of the Western ghats, accumulated waste, upstream pollution are all concerns for their habitat disturbance and degradation. These factors along with their extremely limited distribution make them highly vulnerable to extinction.

Species

There were recognized 2-3 species by Strong et al. in 2008, but Reid et al. described 6 new species of ''Cremnoconchus'' in 2013. Species within the genus ''Cremnoconchus'' include: * '' Cremnoconchus agumbensis'' Reid, Aravind & Madhyastha, 2013Reid D. G., Aravind N. A., & Madhyastha N. A. (2013). "A unique radiation of marine littorinid snails in the freshwater streams of the Western Ghats of India: the genus ''Cremnoconchus'' W.T. Blanford, 1869 (Gastropoda: Littorinidae)". ''

Zoological Journal of the Linnean Society The ''Zoological Journal of the Linnean Society'' is a monthly peer-reviewed scientific journal covering zoology published by Oxford University Press on behalf of the Linnean Society. The editor-in-chief is Maarten Christenhusz (Linnean Society) ...

'' 167(1): 93-135. . * '' Cremnoconchus canaliculatus'' W. T. Blanford, 1870 - synonym: ''Cremnoconchus fairbanki'' Hanley & Theobald, 1876 * '' Cremnoconchus castanea'' Reid, Aravind & Madhyastha, 2013 * '' Cremnoconchus cingulatus'' Reid, Aravind & Madhyastha, 2013 * '' Cremnoconchus conicus'' Blanford, 1870 - synonym: '' Cremnoconchus carinatus'' (Layard, 1854) * '' Cremnoconchus dwarakii'' Reid, Aravind & Madhyastha, 2013 * '' Cremnoconchus globulus'' Reid, Aravind & Madhyastha, 2013 * '' Cremnoconchus hanumani'' Reid, Aravind & Madhyastha, 2013 * '' Cremnoconchus syhadrensis'' (Blanford, 1863)Reid, David G. (2010). ''Cremnoconchus syhadrensis'' (Blanford, 1863). In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=446845 on 2011-09-05 - type species ;Synonyms: * ''Cremnochonchus messageri'' Bavay & Dautzenberg, 1900 is a synonym for '' Paludomus messageri'' (Bavay & Dautzenberg, 1900)

References

{{Taxonbar, from=Q5184093 Littorinidae