Kingdom Animalia Class Cephalopoda Order Nautilida Rank Genus | Phylum Mollusca Subclass Nautiloidea Superfamily Trigonocerataceae | |
Similar Cymatoceras, Nautilida, Nautiloid | ||
Gryponautilus is a genus of Upper Triassic nautilids (generally coiled nautiloid cephalopods) belonging to the trigonoceratacean family Grypoceratidae, characterized by involute, inflated shells, which at maturity develop narrowly rounded keel-like venters. Venters on inner whorls are truncated and broadly convex to concave.
Immature forms bear a resemblance to Grypoceras.
References
Gryponautilus Wikipedia(Text) CC BY-SA