''Rhaeboceras'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of ammonite belonging to the subfamily Scaphitinae. Species belonging to the genus lived during the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

and have been found in the

Pierre Shale The Pierre Shale is a geologic formation or series in the Upper Cretaceous which occurs east of the Rocky Mountains in the Great Plains, from Pembina Valley in Canada to New Mexico. The Pierre Shale was described by Meek and Hayden in 1862 in th ...

of North America.

Taxonomy

The genus ''Ponteixites'' is currently deemed a junior synonym of ''Rhaeboceras'', with most specimens formerly assigned to ''Ponteixites'' appearing to be juveniles. The finding of a larger fossil specimen assigned to ''P. robustus'' similar to these juvenile remains provides evidence supporting this lumping.

References

Cretaceous ammonites Scaphitidae {{Ammonite-stub