''Turbo marmoratus'', known as the green turban, the marbled turban or great green turban, is a large species of marine gastropod with a thick

calcareous Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines. In zoology ''Calcareous'' is used as an ad ...

operculum in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Turbinidae Turbinidae, the turban snails, are a family of small to large marine gastropod molluscs in the superfamily Trochoidea.Bouchet, P. (2014). Turbinidae Rafinesque, 1815. Accessed through: World Register of Marine Species at http://www.marinespecies ...

, the turban snails.WoRMS (2012). ''Turbo marmoratus'' Linnaeus, 1758. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=216369 on 2012-10-01 The shells of these large sea snails have a very thick layer of nacre; this species has been commercially fished as a source of mother of pearl.

Distribution

These large snails live in tropical reefs in the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by t ...

(off

Tanzania Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa within the African Great Lakes region. It borders Uganda to the north; Kenya to the northeast; Comoro Islands ...

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

, Aldabra and the

Mascarene The Mascarene Islands (, ) or Mascarenes or Mascarenhas Archipelago is a group of islands in the Indian Ocean east of Madagascar consisting of the islands belonging to the Republic of Mauritius as well as the French department of Réunion. Thei ...

Basin) and tropical western

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contine ...

oceans; also off

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , establishe ...

, Australia. They are nocturnal and feed on algae.

Description

The distinctive shell grows to a length of 18 cm. The large, imperforate, solid shell is ventricose, as broad as long. Its color pattern is green, marbled with white and rich brown. The 6-7 whorls are flattened or concave above, rounded and bearing two nodose keels below, and a stronger nodose carina above. It bears blunt tubercles, especially strong on the shoulders. Its large, circular

aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An ...

has a golden, pearly shine. The base of the shell is produced. The columellar region is more or less excavated. The subcircular operculum is somewhat concave within. Its outer surface is closely tuberculate and whitish. ''Turbo marmoratus'' is the host of the

ectoparasitic Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson ha ...

copepod '' Anthessius isamusi'' Uyeno & Nagasawa, 2012 The shell of marbled turbans is used as a source of nacre. The large opercula of ''Turbo marmoratus'' have been sold as paperweights or door stops.Man and mollusc
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References

* Oostingh, C.H., 1925. ''Report on a collection of recent shells from Obi and Halmahera, Molluccas''. Mededeelingen van de Landbouwhoogeschool Wageningen, 29(1):1-362. * Allan, J., 1950. ''Australian Shells: with related animals living in the sea, in freshwater and on the land.'' Georgian House, Melbourne. xix 470 pp.. * Drivas, J. & M. Jay (1988). ''Coquillages de La Réunion et de l'île Maurice'' * Wilson, B., 1993. ''Australian Marine Shells. Prosobranch Gastropods''. Odyssey Publishing, Kallaroo, WA * Alf A. & Kreipl K. (2003). ''A Conchological Iconography: The Family Turbinidae, Subfamily Turbininae, Genus Turbo''. Conchbooks, Hackenheim Germany.

External links

* {{Taxonbar, from=Q7853864 marmoratus Gastropods described in 1758 Taxa named by Carl Linnaeus Marine gastropods