Cyrtogomphoceras

Systematic Paleontology

Class Cephalopoda

Subclass Nautiloidea

Order Discosorida

Family Cyrtogomphoceratidae

Genus Cyrtogomphoceras

Cyrtogomphoceras is a discosorid and namesake of the Cyrtogomphoceratidae from the middle and upper Ordovician of the US and Canada. Shells are large, endogastric; dorsal (upper) side convex in profile, ventral (lower) side concave; fusiform overall. Body chamber narrows toward the aperture, hyponomic sinus present. The siphuncle is large, slightly removed from the venter, segments short and broadly expanded; septa necks short, brims strongly re-curved; connecting rings thickened, bullettes swollen

Cyrtogomphoceras has its probable ancestry in Strandoceras, and probably gave rise to Landeroceras.

As with other cyrtogomphoceratids, Cyrtogomphoceras was a benthic carnivore that prowled the sea floor face down in search of its prey.