Stearoceras
Encyclopedia
Stearoceras is an extinct prehistoric nautiloid genus from the Lower Pennsylvanian
(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 that were once diverse and numerous but are now represented by only a handful of species.
Pennsylvanian
The Pennsylvanian is, in the ICS geologic timescale, the younger of two subperiods of the Carboniferous Period. It lasted from roughly . As with most other geochronologic units, the rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain...
(Upper Carboniferous) - Lower Permian
Permian
The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "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
Suture
Surgical suture is a medical device used to hold body tissues together after an injury or surgery. It generally consists of a needle with an attached length of thread. A number of different shapes, sizes, and thread materials have been developed over its millennia of history.-History:Through many...
with broad lateral lobes and a deep ventral saddle as found in syringonautilids
Syringonautilidae
The Syringonautilidae comprise the last of the Trigonocerataceae and are the source for the Nautilaceae which continued the Nautiloidea through the Mesozoic and into the Cenozoic right down to the recent. The Syringonautilidae, itself, is a strictly Triassic family, derived early in the Triassic...
.(ibid)
Nautiloids are a subclass of shelled cephalopods that were once diverse and numerous but are now represented by only a handful of species.
References
- Kümmel, B. 1964. Nautiloidea -Nautilida; Treatise on Invertebrate PaleontologyTreatise on Invertebrate PaleontologyThe Treatise on Invertebrate Paleontology published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and covering every phylum, class, order, family, and genus of fossil and...
Part 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)
See also
- NautiloidNautiloidNautiloids are a large and diverse group of marine cephalopods belonging to the subclass Nautiloidea that began in the Late Cambrian and are represented today by the living Nautilus. Nautiloids flourished during the early Paleozoic era, where they constituted the main predatory animals, and...