| 词条 | Collignoniceras |
| 释义 |
| fossil_range = {{Fossilrange|Turonian}} | image = Gasteropods - Ammonites - Collignoniceras woolgari.JPG | image_caption = Collignoniceras woolgari, from Bílá Hora, Prague, Czech Republic, at the National Museum (Prague) | taxon = Collignoniceras | authority = Breistroffer, 1947 | subdivision_ranks = Species | subdivision = See text }} Collignociceras is a strongly ribbed and tuberculate, evolute ammonite from the Turonian of the western U.S. and Europe belonging to the ammonitid family Collignoniceratidae. The genus is named after the French paleontologist Maurice Collignon. The type is Collignoniceras woollgari, named by Mantell in 1822 for specimens from Sussex, England. The shell is compressed in early growth stages, with rounded or high and clavate siphonal tubercles tending to form a serrate keel, straight or slightly sinuous ribs and weak umbilical and strong ventrolateral tubercles. later whorls tend to be squarer in section with exaggerated ventrolateral tubercles. Two subspecies are known from the Turonian of western North America, C. woollgari wooolgari and C. woollgari regulari. C. w. woollgari has been found with Mammites depressus at the top of the lower shale tongue and lowermost overlying Tres Hermanos sandstone member of the Mancos Shale in New Mexico, in a shale bed at the top of the Greenhorn Formation in Colorado, and alone in sandstone and shale in the upper Frontier Formation in Wyoming. The slightly younger C. w. regulari is known from the lower Carlile Shale, which overlies the Greenhorn. It has been found in U. S. western interior from as far west as northern Arizona and eastern Utah and from New Mexico to Montana. References
3 : Late Cretaceous ammonites of North America|Ammonitida genera|Collignoniceratidae |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。