Anoploceras

Anoploceras
Temporal range: Middle Triassic– Upper Triassic
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order: Nautilida
Family: Tainoceratidae
Genus: Anoploceras
Hyatt in Zittel, 1900

Anoploceras is a Middle and Upper Triassic nautiloid included in the Tainoceratidae, known from eastern Europe. The shell is evolute with only a slight overlap of previous whorls. Whorl section is subquadrate, like Pleuronautilus, only depressed. Flanks have conspicuous ribs that may be somewhat sinuous.

Holconautilus has a more rounded venter, and flanks, and is more evolute. Enoploceras has weaker ribs that expand into nodes on the umbilical and ventro-lateral shoulders, and a small umbilical perforation. Encoiloceras has strong ribbing, a large umbilical perforation, and a shallow groove along the venter.

References


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