''Pseudohaploceras'' is a genus of desmosceratid

ammonite Ammonoids are extinct, (typically) coiled-shelled cephalopods comprising the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which comprise the clade Coleoidea) than they are to nautiluses (family N ...

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Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...

;

Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 137.05 ± 0.2 Ma and 132.6 ± 0.2 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretac ...

Albian The Albian is both an age (geology), age of the geologic timescale and a stage (stratigraphy), stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early Cretaceous, Early/Lower Cretaceous epoch (geology), Epoch/s ...

epochs. with and (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.

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 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 ( Tibasosa Formation, Santa Rosa de Viterbo and Yuruma and Apón Formations,

La Guajira La Guajira () is a departments of Colombia, department of Colombia. It occupies most of the Guajira Peninsula in the northeast region of the country, on the Caribbean Sea and bordering Venezuela, at the northernmost tip of South America. The ca ...

), Egypt, Italy, Japan, Mexico, Serbia and Montenegro, Spain, Tanzania, and the former USSR.''Pseudohaploceras''
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Fossilworks Fossilworks was a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database, a large relational database assembled by hundreds of paleontologists from around the world. History Fossilworks was cr ...

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Description

Distribution

References

Further reading