''Aristoceratoides'' is an extinct

ammonoid 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) ...

genus belonging to the goniatitid family

Thalassoceratidae Thalassoceratidae a family of late Paleozoic ammonites included in the goniatitid superfamily Thalassoceratoidea along with the Bisatoceratidae. Some eight genera are included, although the specific number and exactly which depends on the part ...

that lived during the

Middle Permian The Guadalupian is the second and middle series/epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico and Texas, and dates between 272.95 ± 0. ...

. Named by Ruzhentsev, 1960, the type species is ''"Thalassoceras" varicosum'' Gemmellaro, 1887. The shell of ''Aristoceratoides'' is globose, with ventrolateral furrows; whorls wider than high. The suture is simpler than that of its likely ancestor ''

Aristoceras ''Aristoceras'' is a Late Paleozoic goniatitid genus included in the Goniatitina suborder in which the lobes of the external suture are irregularly serrate. ''Aristoceras'', named by Ruzencev, 1950, may be a synonym for '' Euthalassoceras'' Mil ...

''. Suture elements are simply digitate with digits restricted to the lower half of lobes.

References

* ''Aristoceratoides'' i
GONIAT Online
6/5/12 * W. B. Saunders, D. M. Work, and S. V. Nikolaeva, 1999. Evolution of Complexity in Paleozoic Ammonoid Sutures, Supplementary Material. Science Magazine * Fossils of Italy Goniatitida genera Thalassoceratoidea Permian ammonites Wordian life {{Goniatitida-stub