Anoploceras
Anoploceras is a genus of Middle and Upper Triassic nautiloids 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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