''Rineceras'' is an extinct genus from the
nautilid family
Trigonoceratidae
The Trigonoceratidae is a family of coiled nautiloid cephalopods that lived during the period from the Early Carboniferous ( Mississippian) to the Early Permian.
Diagnosis
Trigonoceratidae comprise members of the order Nautilida characterized ...
which is part of the
Trigonocerataceae, that lived during the
Mississippian
Mississippian may refer to:
* Mississippian (geology), a subperiod of the Carboniferous period in the geologic timescale, roughly 360 to 325 million years ago
* Mississippian cultures, a network of precontact cultures across the midwest and Easte ...
Period in the late Paleozoic.
''Rineceras'' is described in the
Treatise
A treatise is a Formality, formal and systematic written discourse on some subject concerned with investigating or exposing the main principles of the subject and its conclusions."mwod:treatise, Treatise." Merriam-Webster Online Dictionary. Acc ...
, in Kummel, 1964, as being evolute with volutions in contact but not deeply impressed at maturity and the whorl section elliptical and depressed; the conch (shell) bearing prominent longitudinal ridges, which may be spinose. ''Rinceras'' is illustrated, fig. 311-4 p. K429, as a closely coiled gyrocone of about two volutions, whorls not in contact. Longitudinal ridges (ribs) are shown. The illustration is designated as ''R. propinquum'' (DeKoninck), the type.
''Rineceras'' is similar to ''
Pararineceras'', ''
Thrincoceras'', ''
Discitoceras'', and ''
Chouteauoceras'' in that all are covered by numerous longitudinal ridges.
''Rineceras'' was named by Hyatt in 1893. It is based on ''Gyroceras propinquum'' DeKoninck, 1880, found in the Lower Carboniferous of Belgium.
References
* Kummel, B, 1964; Nautiloidea- Nautilida; Treatise on Invertebrate Paleontology Part K Nautiloidea; Geological Society of America and University of Kansas Press.
{{Taxonbar, from=Q16989283
Nautiloids