Trigonocerataceae

The Trigonocerataceae, perhaps now better known as the Trigonoceratoidea, is a superfamily of nautiloid cephalopods that makes up part of the Nautilida, and known from the Devonian to the Triassic. Shells vary from broadly curved exogastric cyrtocones to coiled evolute, often with a large open umbilicus.

Families within include the Trigonceratidae, Centroceratidae, Grypoceratidae, Permoceratidae, and Syringonautilidae