Cremnoconchus is a genus of small freshwater snails, gastropod mollusks in the otherwise marine family Littorinidae, the winkles or periwinkles.[3][5]
| Cremnoconchus | |
|---|---|
| A drawing of Cremnoconchus syhadrensis | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Gastropoda |
| Subclass: | Caenogastropoda |
| Order: | Littorinimorpha |
| Family: | Littorinidae |
| Subfamily: | Lacuninae |
| Genus: | Cremnoconchus Blanford, 1869[1] |
| Diversity[2] | |
| 9 freshwater species | |
| Synonyms[3] | |
| |
The generic name Cremnoconchus is from the Greek word κρημνός which means precipice and from the Ancient Greek word κόγχος which means shell.[1]
This is the only freshwater genus within the Littorinidae; all other genera belonging to the family are marine.[6][5] Molecular dating based on fossil records showed that Cremnoconchus separated from their last marine ancestor around 90 million years ago[7] 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 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.
| violet - Cremnoconchus conicus | |
| green - Cremnoconchus carinatus | |
| dark red - Cremnoconchus syhadrensis. |
The genus Cremnoconchus is endemic to the Western Ghats of India.[7] All Cremnoconchus species live in spray zones of waterfalls[2] 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.[8] These factors along with their extremely limited distribution make them highly vulnerable to extinction.
Species
editThere were recognized 2-3 species by Strong et al. in 2008,[5] but Reid et al. described 6 new species of Cremnoconchus in 2013.[2]
Species within the genus Cremnoconchus include:
- Cremnoconchus agumbensis Reid, Aravind & Madhyastha, 2013[2]
- Cremnoconchus canaliculatus W. T. Blanford, 1870 - synonym: Cremnoconchus fairbanki Hanley & Theobald, 1876[2]
- Cremnoconchus castanea Reid, Aravind & Madhyastha, 2013[2]
- Cremnoconchus cingulatus Reid, Aravind & Madhyastha, 2013[2]
- Cremnoconchus conicus Blanford, 1870[9] - synonym: Cremnoconchus carinatus (Layard, 1854)[9][2][10]
- Cremnoconchus dwarakii Reid, Aravind & Madhyastha, 2013[2]
- Cremnoconchus globulus Reid, Aravind & Madhyastha, 2013[2]
- Cremnoconchus hanumani Reid, Aravind & Madhyastha, 2013[2]
- Cremnoconchus syhadrensis (Blanford, 1863)[9][11] - type species[1][2]
- Synonyms
- Cremnochonchus messageri Bavay & Dautzenberg, 1900 is a synonym for Paludomus messageri (Bavay & Dautzenberg, 1900)[2]
References
edit- ^ a b c Blanford W. T. (1869). "Notes on some Indian and Mascarene Land-Shells". Annals and Magazine of Natural History (4)3: 340-344. page 343.
- ^ a b c d e f g h i j k l m Reid 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 167(1): 93-135. doi:10.1111/j.1096-3642.2012.00875.x.
- ^ a b Bouchet, P.; Reid, David G. (2011). Cremnoconchus Blanford, 1869. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=446361 on 2011-09-05
- ^ Blanford W. T. (1863). "Descriptions of Cremnobates Syhadrensis and Lithotis rupicola, two new Generic Forms of Mollsca inhabiting Cliffs in the Western Ghats of India." Annals and Magazine of Natural History (3)12: 184-187. plate 4, figure 1-7.
- ^ a b c 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 doi:10.1007/s10750-007-9012-6.
- ^ Williams, S. T.; Reid, D. G.; Littlewood, D. T. J. (2003-07-01). "A molecular phylogeny of the Littorininae (Gastropoda: Littorinidae): unequal evolutionary rates, morphological parallelism, and biogeography of the Southern Ocean". Molecular Phylogenetics and Evolution. 28 (1): 60–86. doi:10.1016/S1055-7903(03)00038-1. ISSN 1055-7903.
- ^ a b Saha, Anwesha; Chakraborty, Sudeshna; Ravikanth, G.; Praveen Karanth, K.; Aravind, N. A. (2022-09-01). "Endemicity and radiation in waterfalls of the Western Ghats: The genus Cremnoconchus (Gastropoda: Littorinidae)". Molecular Phylogenetics and Evolution. 174: 107547. doi:10.1016/j.ympev.2022.107547. ISSN 1055-7903.
- ^ Aravind, N. A.; Sarma, Roshmi Rekha; Madhyastha, N. A. (2016). "Conservation of Cremnoconchus Blanford 1869, an iconic freshwater gastropod genus from the Western Ghats, India". Current Science. 111 (6): 1097–1103. ISSN 0011-3891.
- ^ a b c (file created 29 July 2010) "FRESH WATER MOLLUSCAN SPECIES IN INDIA". accessed 5 September 2011. 11 pp. PDF Archived 2012-03-20 at the Wayback Machine.
- ^ Reid, David G. (2010). Cremnoconchus conicus Blanford, 1870. 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=446844 on 2011-09-05
- ^ 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