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''Shouchangoceras'' is pseudohaloritid and type genus for the Shouchangocerinae, characterized by a compressed shell as much as 5 cm in diameter, with a strongly constricted mature peristome that has shallow dorsolateral sinus, a moderately deep rounded ventral sinus, but without conspicuous lappets, and ornamented by moderately strong transverse ribs and numerous stronger longitudinal lirae, producing a weakly reticulate pattern. Lobes are attenuate. The siphuncle is within the dorsal septal flecture. ''Shouchangoceras'' is known from the Upper Permian of Texas and south China. It is the only genus named and described by Zhao & Zheng known also from North America. ''Shouchangoceras'' resembles both ''Shangraoceras'' and ''Sangzhites'' in ornament, all three of which possess transverse ribs and longitudinal lirae. In ''Shouchangoceras'' both are moderately developed. In Shangraoceras lirae are fine, if found at all, while ribs are course. In ''Sangzhites'' both ribs and lirae and strongly developed . ==References== *Frest, T.J, B.F Glenister and W.M Furnish; 1981. Pennsylvanian-Permian Cheiloceratacean Ammonoid Families Maximitidae and Pseudohaloritidae. Memoir 11, the Paleontological Society; Jour Paleo V. 55, May 1981, supplement. *Zhao, J. K. and Zheng, Z. G.. 1977. The Permian ammonoids from Zhejiang and Jiangxi. Acta Palaeontologica Sinica 16:217-252. *(''Shouchangoceras'' ) in Paleobiology db. 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「Shouchangoceras」の詳細全文を読む スポンサード リンク
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