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|status = fossil |image = Stephanoceratidae - Normannites braikenridgei.JPG |image_caption = Fossil specimen of ''Normannites braikenridgei'' from Mid Jurassic - Germany |regnum = Animalia |phylum = Mollusca |classis = Cephalopoda |subclassis = Ammonoidea |ordo = Ammonitida |familia = Stephanoceratidae |genus = ''Normannites'' |genus_authority = Munier-Chalmas 1892 }} ''Normannites'' is a strongly ribbed evolute Middle Jurassic〔 ammonite included in the stephanoceratoid family Stephanoceratidae. ''Normanites'' was previously included in the Otoitidae by Arkell et al. 1957. More recent classifications show it to belong to the family Stephanoceratidae, along with genera like ''Stephanoceras'' and ''Stemmatoceras''. ==Description== ''Normannites'' has shells reaching a diameter of . These shells have large lappets, curved plate-like structures that project forward on either side of the aperture. Primary ribs on the inner side of each whorl are large and close spaced, bifurcate about mid flank before continuing over the venter. Secondary ribs, when present, appear about mid flank between primary pairs. ''Stephanoceras'' differs in its tendency to develop tubercles at the point of furcation in the primary ribs. Primary ribs, low on the whorls, in ''Stemmatoceras'' tend to be narrower and sharper. 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「Normannites」の詳細全文を読む スポンサード リンク
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