''Olenekoceras'' is an

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) ...

cephalopod from the Lower

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...

included in the

ceratitid Ceratitida is an order that contains almost all ammonoid cephalopod genera from the Triassic as well as ancestral forms from the Upper Permian, the exception being the phylloceratids which gave rise to the great diversity of post Triassic ammoni ...

family

Sibiritidae Sibiritidae constitutes a family of ceratitid ammonites described in the Treatise, Part L, 1957, as ribbed or teberculate derivatives of Meekoceritidae with modification of the venter from mere widening and transverse ribbing to sulcation (bein ...

, once included in the

Noritaceae Noritoidea, formerly Noritaceae, is an extinct superfamily of cephalopods belonging to the Ammonite order Ceratitida. Noritoidea, defined by Karpinsky in 1889, combines ceratitids with "typically smooth, more or less discoidal shells with rounde ...

but now in the

Ceratitaceae Ceratitoidea, formerly Ceratitaceae, is an ammonite superfamily in order Ceratitida characterized in general by highly ornamented or tuberculate shells with ceratitic sutures that may become goniatitic or ammonitic in some offshoots. (Arkell ' ...

Distribution

Japan and the Russian Federation.

References

;Notes ;Bibliography * W.J. Arkell, et al., 1957. Mesozoic Ammonoidea; Treatise on Invertebrate Paleontology, Part L. Geological Society of America and University of Kansas Press. Triassic ammonites Fossils of Russia Olenekian life Ceratitida genera Ceratitoidea {{ceratitida-stub