Pseudohaploceras
| Pseudohaploceras | |
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| Phylum: | Mollusca |
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| Genus: | Pseudohaploceras Hyatt, 1900
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Pseudohaploceras is a genus of
Description
The genus is distinguished by its moderately involute, slightly to moderately compressed shell with convex sides and regular straight or sinuous constrictions between which are fairly fine, distinct, sharp or rounded branching ribs extending from the umbilical edge and crossing the venter, the outer rim.
Pseudohaploceras is considered[who?] an offshoot of early Valdedorsella, which differ in having a more broadly rounded whorl section and generally straight radial constrictions. It is included in the subfamily Pizosiinae.
Distribution
Fossils of Pseudohaploceras have been found in Austria, Bulgaria, China, Colombia (
La Guajira), Egypt, Italy, Japan, Mexico, Serbia and Montenegro, Spain, Tanzania, and the former USSR.[2]
References
- ^ Wright, C. W. with Callomon, J.H. and Howarth, M.K. (1996), Mollusca 4 Revised , Cretaceous Ammonoidea, vol. 4, in Treatise on Invertebrate Paleontology, Part L (Roger L. Kaesler ed.), Boulder, Colorado: The Geological Society of America & Lawrence, Kansas: University of Kansas Press, pp. 73, 72.
- ^ Pseudohaploceras at Fossilworks.org
Further reading
- W.J. Arkell; et al. (1957). R.C. Moore (ed.). Mesozoic Ammonoidea, Treatise on Invertebrate Paleontology Part L. Geological Society of America, University of Kansas Press.