''Encoiloceras'' is a genus of Tainoceratids, a

nautiloid Nautiloids are a group of cephalopods (Mollusca) which originated in the Late Cambrian and are represented today by the living ''Nautilus'' and ''Allonautilus''. Fossil nautiloids are diverse and species rich, with over 2,500 recorded species. Th ...

cephalopod in the order

Nautilida The Nautilida constitute a large and diverse order of generally coiled nautiloid cephalopods that began in the mid Paleozoic and continues to the present with a single family, the Nautilidae which includes two genera, ''Nautilus'' and ''Allonauti ...

that has been found in Upper

Triassic The Triassic ( ; sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is t ...

(

Carnian The Carnian (less commonly, Karnian) is the lowermost stage (stratigraphy), stage of the Upper Triassic series (stratigraphy), Series (or earliest age (geology), age of the Late Triassic Epoch (reference date), Epoch). It lasted from 237 to 227.3 ...

) sediments in the

Alps The Alps () are some of the highest and most extensive mountain ranges in Europe, stretching approximately across eight Alpine countries (from west to east): Monaco, France, Switzerland, Italy, Liechtenstein, Germany, Austria and Slovenia. ...

and

Hungary Hungary is a landlocked country in Central Europe. Spanning much of the Pannonian Basin, Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia and ...

. ''Encoiloceras'' has an evolute shell with a wide umbilicus and large umbilical perforation in the middle. The whorl section is subquadrate with a rounded venter. Flanks bear thick, foldlike, ribs that thicken at the ventral shoulders. The suture has shallow lobes on all sides and the supuncle is close to the dorsum, i.e. to the inner rim. ''Encoiloceras'' is similar to '' Anoploceras'' in that both have pronounced ribbing, although stronger in ''Encoiloceras'', but differs in that ''Encoiloceras'' has a wide umbilical perforation, lacking in ''Anoploceras''. It is also similar to '' Enoploceras'' in that ''Enoploceras'' also has an umbilical perforation, although smaller, and lacks the strong ribbing of ''Encoiloceras''.

''References''

* Bernhard Kummel, 1964. Nautiloidea-Nautilida.

Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology,'' published from 1953–2007 by the Geological Society of America and the University of Kansas, then 2009–present by the University of Kansas Paleontological Institute, is a definitive multi-authore ...

, Part K. Geological Soc. of America and University of Kansas press. Teichert and Moore (eds) Prehistoric nautiloid genera {{paleo-Nautiloidea-stub