Hercocyrtoceras is a middle Silurian oncocerid found in Nova Scotia and Quebec. Shells are depressed, irregularly annulated cyrtocones with V-shaped hyponomic sinuses, ornamented by longitudinal and transverse ridges. Position and structure of the siphuncle were unknown as of 1964.
| Hercocyrtoceras Temporal range: Middle Silurian | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | Nautiloidea |
| Order: | †Oncocerida |
| Family: | †Acleistoceratidae |
| Genus: | †Hercocyrtoceras Foeste, 1927 |
Hercocyrtoceras is related to other acleisoceratid genera such as Acleistoceras, Amphycyrtoceras, and Ectocyrtoceras.
References
edit- Walter C Sweet, 1964. Nautiloidea - Oncocerida. Treatise on Invertebrate Paleontology. Part K Geological Society of America and University of Kansas Press.