{{Short description|Species of gastropod}} {{Speciesbox | image = Erronea_onyx_01.JPG | image_caption = Five views of a shell of ''Erronea onyx'' | genus = Erronea | species = onyx | authority = (Linnaeus, 1758) | synonyms_ref =<ref name="WoRMS"/> | synonyms = *''Cypraea onyx'' <small>Linnaeus, 1758</small> (basionym) *''Cypraea pulla'' <small>Gmelin, 1791</small> *''Cypraea prunus'' <small>Röding, 1798</small> }}
'''''Erronea onyx''''', common name the '''onyx cowry''', is a species of sea snail, a cowry, a marine gastropod mollusk in the family Cypraeidae, the cowries.<ref name="WoRMS">{{WRMS species|216860|''Erronea onyx'' (Linnaeus)|||WoRMS (2009). Erronea onyx (Linnaeus). Accessed through the World Register of Marine Species at <nowiki>http://www.marinespecies.org/aphia.php?p=taxdetails&id=216860</nowiki> on 21 October 2010}}</ref>
==Description== thumb|''Cypraea onyx'' S2-21 37mm The shells of these quite common cowries reach on average {{convert|32|-|38|mm}} of length, with a minimum size of {{convert|24|mm}} and a maximum size of {{convert|57|mm}}. The dorsum surface of ''Erronea onyx'' is smooth, shiny and generally golden brown, with alternating longitudinal fuzzy bands of translucent bluish and reddish colors (hence the Latin name ''onyx''). The base and the margins are dark brown or black, sometimes the teeth are orange. In the living cowries mantle is dark brown, quite thin, with bluish papillae. thumb|Shell of ''Erronea onyx'' thumb|Dorsal view of three shells of ''Erronea onyx''
==Distribution== This species occurs the Indian Ocean on the coasts of Aldabra, the Comores, Kenya, Madagascar, Mauritius, Mozambique, Réunion, the Seychelles, Tanzania and in the Pacific Ocean along East China, Thailand, northern Australia, Indonesia, Philippines, Palau Islands and Solomon Islands.
==Habitat== ''Erronea onyx'' lives in tropical and subtropical zones, in shallow subtidal water up to {{convert|5|-|25|m}} depth, mainly in muddy areas or sandy sea floor, feeding on algae or coral polyps.
==Subspecies== What used to be called ''Erronea onyx adusta'', <small> Lamarck, 1810 </small> is now accepted as ''Erronea adusta''.<ref name="WoRMS-adusta">{{WRMS species|223986|''Erronea onyx adusta'' (Lamarck, 1810)|||MolluscaBase (2018). Erronea onyx adusta (Lamarck, 1810). Accessed through the World Register of Marine Species at <nowiki>http://www.marinespecies.org/aphia.php?p=taxdetails&id=2223986</nowiki> on 21 June 2018}}</ref>
==References== {{Reflist}} * Verdcourt, B. (1954). ''The cowries of the East African Coast (Kenya, Tanganyika, Zanzibar and Pemba).'' Journal of the East Africa Natural History Society 22(4) 96: 129-144, 17 pls. * Burgess, C.M. (1970). The Living Cowries. AS Barnes and Co, Ltd. Cranbury, New Jersey
==External links== * {{Gastropods.com|key=2|id=82|title=''Erronea onyx''|access-date=17 January 2019}} * [http://www.marinespecies.org/aphia.php?p=taxdetails&id=216750 WoRMS] * [http://www.flmnh.ufl.edu/cowries/onyx.htm Flmnh] * [http://clade.ansp.org/obis/search.php/52793 Clade]
{{Taxonbar|from=Q5395676}}
onyx Category:Gastropods described in 1758 Category:Animal taxa named by Carl Linnaeus {{Cypraeidae-stub}}