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''Zaraiskites'' is an extinct genus of ammonoid cephalopod that lived during the Volgan stage of the Middle Jurassic in what is now the Russian Platform. ''Zaraiskites'' has a ribbed evolute shell without tubercles. Inner whorls are with normal bifurcate or triplicate ribbing; outer whorl is with virgatotome ribbing with as many as seven secondary ribs taking off successively in front of each primary rib. Related genera in the Virgatitinae include ''Acuticostites'' and ''Virgatites'' ==References== *W.J Arkell, et al., Mesozoic Ammonoidea; Treatise on Invertebrate Paleontology, Part L, 1957. Geological Society of America and University of Kansas Press. *V.V. Mitta, 1993. The Systematic Composition of the Middle Volgian Virgatitidae (Ammonoidea) of Central Asia. Paleontological Journal 27(4). () 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「Zaraiskites」の詳細全文を読む スポンサード リンク
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