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''Teichertoceras'' is a discosorid genus in the family Westonoceratidae characterized by an endogastric curvature to the early portion of the phragmocone. The shell of ''Teichertoceras'' is moderately compressed; the early portion a narrow expanding cyrtocone that in the adult become more swollen, taking on an exogastric aspect. The body chamber in the adult is contracted toward the aperture. The siphuncle is ventral. Bullettes at the adapical ends of the connecting rings are small. ''Teichertoceras'' is thought to have given rise to ''Westonoceras'' and ''Faberoceras'' and to be derived from ''Ulrichoceras''. It is found in geological formations of Middle Ordovician age in North America. ==References== * Teichert, C. 1964. ''Nautiloidea -Discosorida. Treatise on Invertebrate Paleontology, Part K''. Geological Society of America and Univ Kansas Press. * Flower, R.H. and Teichert, C. 1957. ''The Cephalopod Order Discosorida''. University of Kansas Paleontological Contributions. See List of nautiloids 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「Teichertoceras」の詳細全文を読む スポンサード リンク
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