Gleviceras
Encyclopedia
Gleviceras is a psiloceratacean ammonite included in the Lower Jurassic Oxynoticeratidae
Oxynoticeratidae
Oxynoticeratidae is a family of true ammonites from the Lower Jurassic. They are part of the superfamily Psilocerataceae, characterized by mostly involute, oxyconic shells with narrow venter and compressed, lanceolate whorl section. Suture is ammonitic. Ribbing is feeble, hardly functional and...

. Gleviceras is evolute, with a deep umbilicus, and strongly ribbed along the flanks.
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