Temporal range: middle Ordovician
Tofangoceras is a genus of pseudorthoceroid cephalopods from the Middle Ordovician of the USA (NY) and Asia (S. Manchuria, Korea, and Siberia) belonging to the Stereoplasmoceratidae and similar to Stereoplansmoceras .
The shell of Tofangoceras is long, straight, and faintly annulated, less strongly than for Stereoplasmoceras. The siphuncle is central with moderately expanded, spindle-like segments. Aperture unknown.