''Cassis cornuta'', common name the horned helmet, is a

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

of extremely large sea snail, a

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

gastropod mollusc 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 ...

Cassidae The Cassidae are a taxonomic family of medium-sized, large, and sometimes very large sea snails commonly called helmet snails or bonnet snails. These are marine gastropod mollusks in the superfamily Tonnoidea and the clade Littorinimorpha.Gofas ...

, the helmet shells and their allies.Rosenberg, G. (2012). Cassis cornuta (Linnaeus, 1758). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=208963 on 2012-11-25

Description

The length of the shell varies between 50 mm and 410 mm. It is the largest of all helmet shells. It has a very solid, heavy, rotund shell with large, horn-like knobs and a wide, flat base. The shell has a dorsally pale orange colour, its base vivid orange, faintly marked with white and brown.

Habitat

This large sea snail is found on sand and coral rubble, often around reefs.

Distribution

This species occurs in the

Red Sea The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; ...

, 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 ...

, off the southern African coast from northern KwaZulu-Natal and from Mozambique,Steyn, D.G. & Lussi, M. 2005. ''Offshore Shells of Southern Africa'' as well as in the

Pacific Ocean 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 ...

Relevance to humans

The shell of ''Cassis cornuta'' is a very popular collector's item. In some places the snail is hunted for meat and is traditionally roasted in the shell over fire. Because of both of these factors, humans are a major enemy, and the species is now at risk in many places. However, worldwide it is not listed in the

Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biolog ...

. Because this snail hunts the

crown-of-thorns starfish The crown-of-thorns starfish (frequently abbreviated to COTS), ''Acanthaster planci'', is a large starfish that preys upon hard, or stony, coral polyps (Scleractinia). The crown-of-thorns starfish receives its name from venomous thorn-like spine ...

, which feed on corals, ''Cassis cornuta'' has been put under strict protection in

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 , established_ ...

References

* Rippingale, O.H. & McMichael, D.F., 1961. ''Queensland and Great Barrier Reef Shells''. Jacaranda Press, Brisbane. 210 pp. * Abbott, R.T., 1968 1/Dec/1968 ''The helmet shells of the world (Cassidae)''. Part 1. Indo-Pacific Mollusca, 2(9):7-198. * Wilson, B. R. & Gillet, K., 1971. ''Australian Shells''. A. H. & A. W. Reed, Sydney * Salvat, B. & Rives, C., 1975. ''Coquillages de Polynésie''. les editions du pacifique, Papeete - Tahiti. 1-391. * Kay, E.A., 1979. ''Hawaiian marine shells. eef and shore fauna of Hawaii, Section 4: Mollusca.'' Bernice P. Bishop Museum Special Publication 64(4) Bishop Museum Press, Honolulu. xvii + 653 pp. * Wilson, B., 1993. ''Australian Marine Shells. Prosobranch Gastropods''. Odyssey Publishing, Kallaroo, WA. * Kreipl, K., 1997. ''Recent Cassidae''. Verlag Christa Hemman, Weisbaden. 1-151, pls 1-24.

External links

* * {{Taxonbar, from=Q948739 Cassidae Gastropods described in 1758 Taxa named by Carl Linnaeus