''Carinonautilus'' is a genus of extinct, Middle

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

nautilid with a very involute, compressed shell in which the whorl section is higher than wide, umbilicus is small and shallow, or flanks converge on a narrow venter that has a rounded keel. A furrow on either side marks the ventro-lateral shoulder. The genus was erected by Spengler in 1910 on the basis of the holotype, found in Middle Cretaceous strata from India.

References

* Bernard Kummel, 1964. Nautiloidea -Nautilida.Treatise on Invertebrate Paleontology, Part K. Geological Society of America and University of Kansas Press. {{Taxonbar, from=Q5039641 Prehistoric nautiloid genera Aptian genus first appearances Santonian genus extinctions