''Ochetoceras'' is a genus of ammonites, belonging to the

Oppeliidae Oppeliidae are compressed to oxyconic, sculptured Haploceratoidea, either unkeeled, unicarinate, bicarinate, or tricarinate; with sutures in great variety, but ribbing usually more or less falcoid or falcate. The Oppeliidae is the principal famil ...

, that lived during the Late

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...

from the early Oxfordian to the early

Tithonian In the geological timescale, the Tithonian is the latest age of the Late Jurassic Epoch and the uppermost stage of the Upper Jurassic Series. It spans the time between 152.1 ± 4 Ma and 145.0 ± 4 Ma (million years ago). It is preceded by the K ...

, and type for the subfamily

Ochetoceratinae The Ochetoceratinae is a subfamily within the Oppeliidae from the Upper Jurassic, shells of which are typically oxycones with a tricarinate venter and falcoid ribbing, commonly divided by a median lateral groove or fillet. The median (middle) ke ...

. The shell of ''Ochetoceras'' is rather involute and strongly ribbed. The whorl section is compressed, higher than wide, and deeply impressed by the previous whorl. Flanks are broadly convex and converge to a narrowly rounded venter. Flanks are in two parts, inner and outer, separated by a lateral groove found also in ''

Glochiceras ''Glochiceras'' is a haploceratid ammonite characterized by a small, smooth, compressed, evolute shells with large lappets and a median lateral groove. Its geographic distribution is fairly cosmopolitan, but it is limited stratigraphically to t ...

'' and less pronounced in '' (Chanasia)''. Inner ribs slant strongly forward going radially outward and a fairly wide spaced. Outer ribs are fairly radial but curve slightly forward at the ventro-lateral shoulder; are more numerous and closer spaced. The narrow venter is smooth with a pronounced median keel. ''Ochetoceras'' has been found in Europe, North Africa, Russia, Iran, Mexico, Cuba, and Chili. The type, ''O. canaliculatum'' (Buch) is from the Oxfordian of Germany.

References

;Notes ;Bibliography * W.J. Arkell, et al. 1957 Mesozoic Ammonoidea. Treatise on Invertebrate Paleontology, Part L. Geological Society of America and University of Kansas Press.

External links

Genus Ochetoceras
Ammonitida genera Late Jurassic ammonites Ammonites of North America Ammonites of Europe {{ammonite-stub