''Tainonautilus'' is an extinct coiled cephalopod that lived during the Permian and Early Triassic which is included in the

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 ...

family

Tainoceratidae Tainoceratidae is a family of late Paleozoic and Triassic nautiloids that are a part of the order Nautilida, characterized by large, generally evolute shells with quadrate to rectangular whorl sections. Shells may bear ribs or nodes, or both. ...

. ''Tainonautilus'' has an evolute shell with a subquadrate whorl section. Flanks and outer rim (venter) are flat. The umbilicus is wide and deep; umbilical shoulders have a prominent keel. The sides bear curved retrograde ribs or folds that slant to the rear going from the inner (umbilical) rim to the outer (ventral). The venter, which forms the outer rim has a smooth median sulcus. The siphuncle is subventral, lying near but not on the outer margin. ''Tainonautilus'' has been found 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. ...

in Europe and in the

Salt Range The Salt Range ( and Namkistan نمکستان) is a mountain range in the north of Punjab province of Pakistan, deriving its name from its extensive deposits of rock salt. The range extends along the south of the Potohar Plateau and the north ...

Pakistan Pakistan, officially the Islamic Republic of Pakistan, is a country in South Asia. It is the List of countries and dependencies by population, fifth-most populous country, with a population of over 241.5 million, having the Islam by country# ...

References

* 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 Mollusca 3. Geol Soc of America and Univ Kansas Press; Teichert and Moore (eds) {{Taxonbar, from=Q7676211 Nautiloids Permian first appearances Early Triassic extinctions Prehistoric nautiloid genera