| Tofangoceras Temporal range: middle Ordovician | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Order: | † Orthocerida |
| Family: | † Stereoplasmoceratidae |
| Genus: | † Tofangoceras Kobayashi, 1927 |
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.
