Cooperoceras

Cooperoceras is a genus of Tainoceratid nautiloid cephalopod mollusk within the superfamily Tainocerataceae, characterized by and evolute shell with an open, perforate, umbilicus, sinuous ribs at maturity, and recurved hollow spines along the ventro-lateral shoulders. The flanks and venter are flattened, the flanks converge on the dorsum, the venter has a shallow median groove. The suture is with rounded ventral and lateral lobes. The siphuncle is small, tubular, and subcentral. (Kummel 1964, K413) The phylogenetic relationships of Cooperoceras are unclear.

Cooperoceras

Cooperoceras is a genus of Tainoceratid nautiloid cephalopod mollusk within the superfamily Tainocerataceae, characterized by and evolute shell with an open, perforate, umbilicus, sinuous ribs at maturity, and recurved hollow spines along the ventro-lateral shoulders. The flanks and venter are flattened, the flanks converge on the dorsum, the venter has a shallow median groove. The suture is with rounded ventral and lateral lobes. The siphuncle is small, tubular, and subcentral. (Kummel 1964, K413) The phylogenetic relationships of Cooperoceras are unclear.