Kentlandoceras

Kentlandoceras is a genus of middle Ordovician Oncocerids (family Oncoceratidae). Its shell is curved exogastrically, such that the ventral margin is longitudianally convex, but less so than in Loganoceras, and with a submarginal ventral siphuncle instead. The siphuncle in Loganoceras is subcentral. The related Romingoceras is more curved, also with a ventral siphuncle.

All three genera are from the Middle Ordovician of North America.