Teichertoceras

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Teichertoceras
Temporal range: M Ordovician
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Nautiloidea
Order: Discosorida
Family: Westonoceratidae
Genus: Teichertoceras
Foeste, 1933

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.

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<span class="mw-page-title-main">Phragmoceratidae</span> Extinct family of molluscs

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Hectoceras is a genus in the nautiloid cephalopod order Discosorida from the Upper Ordovician of Australia (Tasmania), known from a few isolated siphuncle specimens.

Reedsoceras is a genus of large discosorids (Nautiloidea) in the family Westonoceratidae from the middle and upper Ordovician of North America.

Simardoceras is a genus in the discosorid family Westonoceratidae from the Middle Ordovician of Quebec.

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Cyrtogomphoceras is a genus of nautiloid cephalopods, recognized by its large breviconic shell with a notable endogastric curvature. The shell is fusiform in profile, reaching maximum width at or near the base of body chamber, which narrows toward the aperture. The siphuncle is large and slightly removed from the ventral side, that with the concave longitudinal profile. Siphuncle segments are short, as are chambers; septal necks recurved, connecting rings thick, bullettes at the apical end of the rings swollen. Cameral deposits are lacking.

Kiaeroceras is a slender, nearly stright shelled, cyrogomphoceratid (Nautiloidea-Discosorida) from the Upper Ordovician of northern Europe. The cross section of the shell is compressed, height greater than width. The body chamber is slightly contracted so as to narrow toward the aperture, which in some is slightly flared. The venter, narrowly rounded. The siphuncle is close to the venter, septal necks short, connecting rings thick, bullettes prominent.

Parryoceras is a cyrtogomphoceratid similar to Strandoceras but with broadly expanded siphuncle segments and a nearly straight ventral line. The mature shell is thickened on the inside just behind the aperture resulting in a constriction in the internal mold at the adoral end.

Discosoridae comprise a family of endogastric discosorids,, with endocones in the siphuncle, ranging from the Middle Silurian to Middle Devonian.

References