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| image = Arcticoceras.jpg | image_width = 250px | image_caption = ''Arcticoceras cranocephaloides'' fossils at the Geological Museum in Copenhagen |regnum = Animalia |phylum = Mollusca |classis = Cephalopoda |subclassis = Ammonoidea |ordo = Ammonitida |superfamilia = Stephanocerataceae |familia = Cardioceratidae |genus = ''Arcticoceras'' | genus_authority = Spath,(1924) |subdivision_ranks = |subdivision = }} ''Arcticoceras'' is an extinct ammonoid cephalopod genus from the late Middle Jurassic belonging to the ammonite family Cardioceratidae, more commonly found to high northern latitudes. The ''Arcticoceras'' shell is involute, inner whorls sharply ribbed, outer ones becoming smooth.〔Arkell et al,1957, Mesozoic Ammonoidea, Treatise on Invertebrate Paleontology, Part L, Mollusca 4, R.C. Moore, ed. p.L301 -L303〕 The suture, following the description of the Sephanocerataceae, is complex, ammonitic, with a dominant 1st lateral lobe and well-developed umbilical lobe. May be derived from ''Arctocephalites''. ''Arcticoceras'' is found in northern Alaska, arctic Canada, Greenland, northern and central Russia, as well as in Wyoming, North Dakota, and Utah.〔 Part of the fauna that lived in high latitude (arctic and subarctic) marine waters during the second half of the Middle Jurassic. ''Arcticoceras kochi'' and ''A ishmanae'' have been found in the boreal Bathonian stage of central East Greenland.〔()〕 ''Arcticoceras'' and ''Arctocephalites'' are found the Volga River Basin, Sartov Region, and ''Arctocephalites'' in the Pechora River Basin indicating an earlier and deeper penetration of arctic water into European Russia than previously thought.〔( Correlation of Upper Bajocian-Bathonian Zones in Siberia )...S.V. Meledina et al 2009〕 ==References== 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「Arcticoceras」の詳細全文を読む スポンサード リンク
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