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|image = Aspidoceras 1.JPG |image_width = |image_caption = ''Aspidoceras'' species |color = rgb(211,211,164) |phylum = Mollusca |classis = Cephalopoda |subclassis = Ammonoidea |ordo = Ammonitida |superfamilia = Perisphinctaceae |familia = Aspidoceratidae |genus = ''Aspidoceras'' |genus_authority = Zidttel, 1868 }} ''Aspidoceras'' is an extinct ammonoid cephalopod genus that lived during the Late Jurassic (Kimmeridgian) with a fairly broad distribution. ''Aspidoceras'', named by Zittel, 1868, is the type genus for the persphictacian family Aspidoceratidae and subfamily Aspidoceratinae in which it is included. ''Aspidoceras'' has an evolute shell with quadrate-rounded or depressed whorls that have two rows of tubercles, the outer near the middle of the whorl sides. The outer row soon fades in many species. Some species are also ribbed. The venter, or outer rim, is generally wide and broadly arched. ''Aspidoceras'' is predated by ''Euaspidoceras'', possibly its ancestor, and is considered related to genera like ''Orthaspidoceras'', ''Simaspidoceras'', and ''Intranodites''. ==References== * Arkell, et al.,1957. Mesozoic Ammonoidea; Treatise on Invertebrate Paleontology, Part L (Ammonoidea). Geol Soc of America and Univ Kansas Press. p. L338-339. 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「Aspidoceras」の詳細全文を読む スポンサード リンク
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