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Cone snails, cone shells or cones are common names for a large group of small to large-sized predatory sea snails, marine gastropod molluscs.〔( Puillandre N., Duda T.F., Meyer C., Olivera B.M. & Bouchet P. (2014). ''One, four or 100 genera? A new classification of the cone snails''. Journal of Molluscan Studies. 81: 1-23 )〕 Until recently, over 600 species of cone snails were all classified under one genus, ''Conus'', in one family, the Conidae. However, in recent years it was suggested both that cone snails should occupy only a subfamily, and that cone snails be split into a very large number of genera. A 2014 paper attempted to stabilize a newer classification of the group, significantly reducing the number of new genera, but keeping a fairly large number of subgenera. Although the taxonomy has changed significantly several times during recent years, in the current (2015) version of the taxonomy of these snails and their close relatives, cone snails once again comprise the entire family Conidae. Geologically speaking, fossils of cone snails are known from the Eocene to the Holocene epochs.〔 Pek I., Vašíček Z., Roček Z., Hajn. V. & Mikuláš R. (1996). ''Základy zoopaleontologie''. Olomouc, 264 pp., ISBN 80-7067-599-3.〕 Cone snail species have shells that are shaped more or less like geometric cones. Many species have colorful patterning on the shell surface. Cone snails are almost all tropical in distribution. Because all cone snails are venomous and capable of "stinging" humans, live ones should be handled with great care or preferably not at all. The species most dangerous to humans are the larger cones, which prey on small bottom-dwelling fish; the smaller species mostly hunt and eat marine worms. Cone snails use a hypodermic needle-like modified radula tooth and a venom gland to attack and paralyze their prey before engulfing it. The tooth is sometimes likened to a dart or a harpoon. It is barbed, and can be extended some distance out from the head of the snail, at the end of the proboscis. Cone snail venoms are mainly peptides. The venoms contain many different toxins that vary in their effects; some are extremely toxic. The sting of small cones is no worse than a bee sting, but the sting of a few of the larger species of tropical cone snails can be serious, occasionally even fatal to humans. Cone snail venom is showing great promise as a source of new, medically important substances. ==Distribution and habitat== There are over 800 different species of cone snails.〔Bouchet, P.; Gofas, S. (2015). Conus Linnaeus, 1758. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=137813 on 2015-03-29〕 Cone snails are typically found in warm and tropical seas and oceans worldwide, and they reach their greatest diversity in the Western Indo-Pacific region. However, some species are adapted to temperate environments, such as the Cape coast of South Africa,〔Tenorio, M. J. & Monteiro, A. J. (2008). ''The Family Conidae. The South African species of'' Conus. In: Poppe, G. T. & Groh, K. (eds): ''A Conchological Iconography''. Hackenheim: ConchBooks. 47 pp., 60 pls.〕 the Mediterranean,〔Monteiro, A. J., Tenorio, M. J. & Poppe, G. T. (2004). ''The Family Conidae. The West African and Mediterranean species of'' Conus. In: Poppe, G. T. & Groh, K. (eds): ''A Conchological Iconography''. Hackenheim: ConchBooks. 102 pp., 164 pls.〕 or the cool waters of southern California (''Conus californicus''),〔Tenorio, M. J., Tucker, J. K. & Chaney, H. W. (2012). ''The Families Conilithidae and Conidae. The Cones of the Eastern Pacific''. In: Poppe, G. T. & Groh, K. (eds): ''A Conchological Iconography''. Hackenheim: ConchBooks. 112 pp., 88 pls.〕 and are endemic to these areas. Cone snails are found in all tropical and subtropical seas from the intertidal zone to deeper areas, living on sand or among rocks or coral reefs. When living on sand, these snails bury themselves with only the siphon protruding from the surface. Many tropical cone snails live in or near coral reefs. Some species are found under rocks in the lower intertidal and shallow subtidal zones. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「cone snail」の詳細全文を読む スポンサード リンク
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