Endoceratidae
| Endoceratidae Temporal range: | |
|---|---|
| Fossil of Endoceras in Milan | |
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | Nautiloidea |
| Order: | †Endocerida |
| Family: | †Endoceratidae Hyatt, 1884 |
Endoceratidae, from Ancient Greek ἔνδον (éndon), meaning "inside", and κέρας (kéras), meaning "horn", is a family of large to very large straight-shelled nautiloid cephalopods belonging to the order Endocerida that lived during the Middle and Late Ordovician. They include the largest known Paleozoic invertebrates, represented by Endoceras and Cameroceras.