| Ascocerida Temporal range:
| |
|---|---|
| |
| The ontogeny of Ascoceras, an Ascoceridian | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | †Orthoceratoidea |
| Order: | †Ascocerida Kuhn, 1949 |
The Ascocerida are comparatively small, bizarre Orthoceratoids known only from Ordovician and Silurian sediments in Europe and North America, uniquely characterized by a deciduous conch consisting of a longer juvenile portion and an inflated short adult portion that separate sometime in maturity.[1]
- ^ W.M . Furnish and Brian F Glenister; Nautiloidea-Ascocerida, K261-K277; Treatise on Invertebrate Paleontology, part K, Nautiloidea; Geological Society of America and the University of Kansas Press, 1964