''Teichertoceras'' is a discosorid genus in the family

Westonoceratidae Westonoceratidae are exogastric, mostly compressed, Discosorida of moderate size from the Middle Ordovician to the Lower Silurian. The siphuncle is typically close to the convexly curved outer margin of the phragmocone – the chambered part o ...

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 The siphuncle is a strand of tissue passing longitudinally through the shell of a cephalopod mollusk. Only cephalopods with chambered shells have siphuncles, such as the extinct ammonites and belemnites, and the living nautiluses, cuttlefish, and ...

is ventral. Bullettes at the adapical ends of the connecting rings are small. ''Teichertoceras'' is thought to have given rise to '' Westonoceras'' and ''

Faberoceras ''Faberoceras'' is an extinct genus of prehistoric nautiloid Nautiloids are a group of marine cephalopods (Mollusca) which originated in the Late Cambrian and are represented today by the living ''Nautilus'' and '' Allonautilus''. Fossil naut ...

'' and to be derived from ''

Ulrichoceras ''Ulrichoceras'' is recognised as the basal cyrtogomphoceratid genus, which is the source for the rest of the Cyrtogomphoceratidae as well as for the Westonoceratidae. The Cyrtogomphoceratidae are endogastric, the Westonoceratidae, exogastric. ' ...

''. 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. {{Taxonbar, from=Q7694955 Discosorida Paleozoic life of Nunavut Prehistoric nautiloid genera