Melarhaphe neritoides
Introduction '''''Melarhaphe neritoides''''', common name : the '''small periwinkle''',  is a species of small sea snail, a marine gastropod mollusc in the family Littorinidae, the winkles or periwinkles.This species was previously known as ''Littorina neritoides''. '''''Melarhaphe''''' is a monotypic genus, in other words, this is the only species in that genus.
Description and habitat This is a tiny species with the size of an adult shell varying between 4 mm and 9 mm. It has a high pointed spire. The dark aperture is oval. The purple-brown spiral band can be clearly seen on the body whorl.The small periwinkle breeds in late winter. Its pelagic egg capsules release planktonic larvae.This small gastropod lives in the upper levels of natural or artificial rocky shores, up to the limit of the highest tides, where it can be abundant and is often the only marine gastropod. It feeds on detritus and on black lichen of the genus ''Lichina''''.''
Distribution This species is found in European waters from Norway down south, in the Atlantic Ocean along the Azores, Canary Islands, Cape Verde, Morocco, Mauritania; in the Mediterranean Sea and the Black Sea.
References *  WoRMS info
Further reading * Backeljau, T. (1986). ''Lijst van de recente mariene mollusken van België List of the recent marine molluscs of Belgium''. Koninklijk Belgisch Instituut voor Natuurwetenschappen: Brussels, Belgium. 106 pp* Reid, D.G. (1989) ''The comparative morphology, phylogeny and evolution of the gastropod family Littorinidae''. Philosophical Transactions of the Royal Society of London, Series B 324: 1-110. * Britton J. C. (1995) "The relationship between position on shore and shell ornamentation in 2 size-dependent morphotypes of ''Littorina striata'', with an estimate of evaporative water-loss in these morphotypes and in ''Melarhaphe neritoides''". ''Hydrobiologia'' '''309''': 129-142.abstract. * Howson, C.M. ; Picton, B.E. (Ed.) (1997). ''The species directory of the marine fauna and flora of the British Isles and surrounding seas''. Ulster Museum Publication, 276.The Ulster Museum: Belfast, UK. . vi, 508* de Kluijver, M.J.; Ingalsuo, S.S.; de Bruyne, R.H. (2000). ''Macrobenthos of the North Sea'' CD-ROM: 1.Keys to Mollusca and Brachiopoda. World Biodiversity Database CD-ROM Series. Expert Center for Taxonomic Identification (ETI): Amsterdam, the Netherlands. . 1 cd-rom pp* Kantor Yu.I. & Sysoev A.V. (2006) ''Marine and brackish water Gastropoda of Russia and adjacent countries: an illustrated catalogue''. Moscow: KMK Scientific Press. 372 pp. + 140 pls. * Cabral-Oliveira J., Maranhão P. & Pardal M. Â. (June 2009) "The effect of sewage discharge on ''Melarhaphe neritoides'' (Gastropoda: Littorinidae) population dynamics". ''Scientia Marina'' '''73'''(2): 259-267. * Reid D.G. (2011) ''The genus Echinolittorina Habe, 1956 (Gastropoda: Littorinidae) in the eastern Atlantic Ocean and Mediterranean Sea.'' Zootaxa 2974: 1–65. * Kadolsky D. (2012) ''Nomenclatural comments on non-marine molluscs occurring in the British Isles.'' Journal of Conchology 41(1): 65-90. * Fourdrilis S., Mardulyn P., Hardy O. J., Jordaens K., de Frias Martins A. M., Backeljau T. (2016) "Mitochondrial DNA hyperdiversity and its potential causes in the marine periwinkle ''Melarhaphe neritoides'' (Mollusca: Gastropoda)". ''PeerJ'' '''4:e2549'''.