 Ammonoceratites

Ammonoceratites is an extinct genus of ammonoid cephalopod known from the Albian (upper Lower Cretaceous) of British Columbia, Madagascar, New Zealand, and Japan, included in the Lytoceratidae.The shell of "Ammonoceratites" is evolute, smooth, moderately expanded; the inner rim (dorsum) only slightly impressed; whorl section subcircular.