Oxygonioceras
| Oxygonioceras Temporal range: M Silurian | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | Nautiloidea |
| Order: | Oncocerida |
| Family: | Brevicoceratidae |
| Genus: | Oxygonioceras |
Oxygonioceras is a genus in the Oncocerid family, Brevicoceratidae, from the Middle Silurian of North America and Europe.
Oxygonioceras, named by Foeste, 1925, has a loosely coiled, dextrally torticonic shell with a rounded dorsum on the inside of the spiral and an angular or subangular venter on the outside; suture with broad lateral lobes and ventral siphuncle with expanded, nummuloidal segments.
Although also torticonically gyroconic -- having an out of plane open spiral - Oxygonioceras differs from Naedyceras and closely related genera in that the siphuncle segments are empty, rather than being actinosiphonate.
See also
References
- Sweet. W. C. 1964. Nautiloidea-Oncocerida; Treatise on Invertebrate Paleontology, Part K. Geol Soc of America and Univ Kansas press, R.C. Moore (Ed)
This article is issued from Wikipedia - version of the 2/23/2011. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.