| Discosorus Temporal range: MiddleSilurian | |
|---|---|
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | Nautiloidea |
| Order: | †Discosorida |
| Family: | †Discosoridae |
| Genus: | †Discosorus Hall, 1852 |
Discosorus, a genus of theDiscosorida and member of the familyDiscosoridae. Not to be confused withDiscoceras.Discosorus consists of rapidly expandingendogastric brevicones, mostly known from isolatedsiphuncles composed of broadly expanded segments that increase rapidly in size. Septal necks are recumbent, connecting rings thin, bullettes small. The siphuncle interior is occupied by endocones produced by layered annular deposits expanded back toward the apex, leaving a central tube running down the middle. The shortphragmocone is poorly known.
Discosorus is found in the MiddleSilurian of eastern and arctic North America and as part of the Discosoratidae is derived from theLowoceratidae which forms a link in theEarly Silurian from the LateOrdovician exogastricFaberoceras of theWestonoceratidae.