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The Cravenoceratidae is one of six families included in the ammonoid superfamily Neoglyphiocerataceae, which lived during the latter part of the Paleozoic era. Cravenoceratid genera have moderately evolute to involute, broad or thickly discoidal shells with a moderately narrow umbilicus. The surface is generally smooth, dominated by growth striae. Spiral ornamentation may be present, but reticulate ornament is absent. The ventral lobe is double pronged and relatively narrow, with the median saddle in most forms less than half of height of entire lobe itself. ==References== * (The Paleobiology Database ) 10/01/07 * ( GONIAT online ) 10/15/11 * Saunders, Work, and Nikolaeva, 1999. Evolution of Complexity in Paleozoic Ammonoid Sutures, Supplementary Material. () 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「Cravenoceratidae」の詳細全文を読む スポンサード リンク
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