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''Gradiconus'' is a subgenus of sea snails, marine gastropod mollusks in the genus ''Conus'', family Conidae, the cone snails and their allies. T In the new classification of the family Conidae by Puillandre N., Duda T.F., Meyer C., Olivera B.M. & Bouchet P. (2015), ''Africonus'' has become a subgenus of ''Conus'': ''Conus (Dauciconus)'' Cotton, 1945 (type species: ''Conus gradatus'' W. Wood, 1828) represented as ''Conus'' Thiele, 1929 〔( Puillandre N., Duda T.F., Meyer C., Olivera B.M. & Bouchet P. (2015). ''One, four or 100 genera? A new classification of the cone snails''. Journal of Molluscan Studies. 81: 1-23 )〕 ==Distinguishing characteristics== The Tucker & Tenorio 2009 taxonomy distinguishes ''Gradiconus'' from ''Conus'' in the following ways:〔Tucker J.K. & Tenorio M.J. (2009), Systematic Classification of Recent and Fossil Conoidean Gastropods, ConchBooks, Hankenheim, Germany, 295 pp.〕 * Genus ''Conus'' ''sensu stricto'' Linnaeus, 1758 :: Shell characters (living and fossil species) :::The basic shell shape is conical to elongated conical, has a deep anal notch on the shoulder, a smooth periostracum and a small operculum. The shoulder of the shell is usually nodulose and the protoconch is usually multispiral. Markings often include the presence of tents except for black or white color variants, with the absence of spiral lines of minute tents and textile bars. ::Radular tooth (not known for fossil species) :::The radula has an elongated anterior section with serrations and a large exposed terminating cusp, a non-obvious waist, blade is either small or absent and has a short barb, and lacks a basal spur. ::Geographical distribution :::These species are found in the Indo-Pacific region. ::Feeding habits :::These species eat other gastropods including cones.〔 * Subgenus ''Gradiconus'' da Motta, 1991 ::Shell characters (living and fossil species) :::The shell is turbinate in shape. The protoconch is paucispiral, cords are either absent or disappear in the early postnuclear whorls. The anal notch is deep. The shell may be ornamented with hemispherical nodules undulating along the shoulder angle in the early postnuclear whorls, and ridges may persist or die out on the body whorl. The color pattern consists of dots or dashes in spiral lines and/or longitudinal markings. The periostracum is tufted or has a fringe along the shoulder angle, and the operculum is small to minute. ::Radular tooth (not known for fossil species) :::The anterior section of the radular tooth is roughly equal to the length of the posterior section, and the blade is more than half the length of the anterior section. A basal spur is present, the barb is short, and there is an internal terminating cusp. The radular tooth is serrated. ::Geographical distribution :::The species in this genus occur in the West Atlantic and Eastern Pacific regions. ::Feeding habits :::These cone snails are vermivorous, meaning that the cones prey on polychaete worms.〔 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「Gradiconus」の詳細全文を読む スポンサード リンク
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