Pseudohaploceras

Pseudohaploceras is a genus of desmosceratid ammonites from the Early Cretaceous; Valanginian to Albian epochs. 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 Temporal range: Early Cretaceous ~145–109 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Order:	Ammonitida
Family:	Desmoceratidae
Subfamily:	Pizosiinae
Genus:	Pseudohaploceras Hyatt, 1900
Species
P. liptoviense P. matheroni P. portaeferreae P. reesidei P. tachthaliae

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, China, Colombia (Tibasosa Formation, Santa Rosa de Viterbo and Yuruma and Apón Formations, La Guajira), Egypt, Italy, Japan, Mexico, Serbia and Montenegro, Spain, Tanzania, and the former USSR.[1]

References

1. 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.