Gryponautilus

Extinct genus of molluscs

Gryponautilus is a genus of Upper Triassic nautilids 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.

This keyword could refer to multiple things. Here are some suggestions: