''Stearoceras'' is an extinct genus of prehistoric
nautiloids from the Lower
Pennsylvanian Pennsylvanian may refer to:
* A person or thing from Pennsylvania
* Pennsylvanian (geology)
The Pennsylvanian ( , also known as Upper Carboniferous or Late Carboniferous) is, in the International Commission on Stratigraphy, ICS geologic timesca ...
(Upper Carboniferous) - Lower
Permian with a fair worldwide distribution.(Kümmel 1964)
''Stearoceras'' is recognized by its involute shell with a depressed subtrapizoidal whorl section and slight ventral and lateral lobes. In contrast Stenoporceras is subdiscoidal and has a
suture with broad lateral lobes and a deep ventral saddle as found in
syringonautilids.(ibid)
Nautiloids are a subclass of shelled
cephalopods
A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, an ...
that were once diverse and numerous but are now represented by only a handful of species.
See also
*
Nautiloid
**
List of nautiloids
References
* Kümmel, B. 1964. Nautiloidea -Nautilida;
Treatise on Invertebrate PaleontologyPart K, Curt Teichert & R.C Moore,(eds) Geological Society of America & Univ. Kansas Press.
* Sepkoski, J.J. Jr. 2002. A compendium of fossil marine animal genera. D.J. Jablonski & M.L. Foote (eds.). ''Bulletins of American Paleontology'' 363: 1–560
Sepkoski's Online Genus Database (CEPHALOPODA)
Prehistoric nautiloid genera
Pennsylvanian first appearances
Cisuralian genus extinctions
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