Species
Orthoceras excentricum Sowerby, 1839
Classification
| Organism group | Biota |
| Kingdom | Animalia |
| Phylum | Mollusca |
| Class | Cephalopoda |
| Subclass | Orthoceratia |
| Order | Orthocerida |
| Suborder | Orthoceratina |
| Family | Orthoceratidae |
| Subfamily | Orthoceratinae |
| Genus | Orthoceras |
| Species | arcuolyratum |
| bifoveatum | |
| calamiteum | |
| compressum | |
| excentricum | |
| hoernesi | |
| luhai | |
| regulare | |
| revalense | |
| scabridum |