Clinoceratidae

Systematic Paleontology Order: Orthocerida, Nautiloidea, Cephalopoda Family: Clinoceratidae

The Clinoceratidae is a family of nautiloid cephalopods included in the Orthocerida in which the shells are faintly curved and rather fusiform longiconic cyrtocones with no hyponomic sinus. Siphuncles are variable in position, depending on genus. Segments are slender and free of organic deposts. Apertures are inclined slightly forward from dorsum (upper side) to venter (lower side).

The Clinoceratidae may have its origin in the Sactorthoceratidae, specifically in Centroonoceras and is probably ancestral to the Ascocerida. Stratigraphic range: middle to upper Ordovician.

Genera include Clinoceras, Whiteavesites, and Whitfieldoceras.

References: Walter C. Sweet, 1964. Nautiloidea -Orthocerida Treatise on Invertebrate Paleontology, part K.