''Pseudohaploceras'' is a genus of desmosceratid

ammonite Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) ...

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Early Cretaceous The Early Cretaceous ( geochronological name) or the Lower Cretaceous (chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma. Geology Pro ...

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Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 139.8 ± 3.0 Ma and 132.9 ± 2.0 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretaceou ...

to Albian 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 Formation The Apón Formation is a geological formation in northwestern Venezuela (Maracaibo Basin) and northern Colombia (La Guajira),García González et al., 2010 whose thick-bedded limestone interbedded with subordinate amounts of dark gray calcareous s ...

s, La Guajira), Egypt, Italy, Japan, Mexico, Serbia and Montenegro, Spain, Tanzania, and the former USSR.''Pseudohaploceras''
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Fossilworks Fossilworks is a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals ...

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Description

Distribution

References

Further reading