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|regnum = Animalia |phylum = Mollusca |classis = Cephalopoda |subclassis = Ammonoidea |ordo = Ammonitida |familia = Nostoceratidae |genus = ''Axonoceras'' |genus_authority = Stephenson, 1941 |subdivision_ranks = species |subdivision = *see text}} ''Axonoceras'' is a genus in the ammonitid family Nostoceratidae proposed by Stephenson in 1941, for "slender shells coiled in a plane with numerous closely spaced ribs and two rows of ventral nodes'...The shells may be closely coiled, though not involute, but most... are more or less loosely and irregularly coiled''. Shells may be coplanar or coiled in a low flat spiral with the early whorls in contact, later whorls free. ''Axonoceras'' comes from the Campanian of Texas and New Jersey in the US and Angola in west Aftrica. The type species is ''Axonoceras compressum'' Stephenson 1941. ''Axonoceras'' and ''Exiteloceras'' are similar with Axonoceras sometimes considered a subjective synonym of ''Exiteloceras''. The adult of ''Axonoceras'' however is very small. ''Exiteloceras'' is much larger ==References== ;Notes ;Bibliography * Ammonites from the Navesink Formation at Atlantic Highlands, New Jersey; by William A Cobban 1974, USGS Prof Paper 845. * 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「Axonoceras」の詳細全文を読む スポンサード リンク
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