Siberionautilidae is a family in the nautilid superfamily Clydonautiloidea that contains only the genus ''Siberionautilus'', which comes from the Upper Triassic ( Carnian) of Siberia, Russia. The family, and genus, are characterized by an involute, globular shell covered by fine radial ribs, with flattened flanks that converge toward a rounded venter, distinct umbilicus with rounded shoulders, differentiated suture, and central siphuncle. The suture is goniatitic with the ventral or median saddle of the Clydonautilidae, subdivided so as to have a deep finger-like median ventral lobe bracketed by finder-like secondary lobes and saddles, and on either side, a large claw-like asymmetric lateral lobe. Like '' Gonionautilus'', ''Siberionautilus'' is derived from the Clydonautilidae, only the genus is unspecified. As with ''Gonionautilus'' and more advanced Clydonautilidae, ''Siberionautilus'' is one of a handful of nautilids that have goniatitic sutures as found in primitive ammonoids.

References

* Bernhard Kummel, 1964. Nautiloidea -Nautilida; Treatise on Invertebrate Paleontology, Part K. Geol Soc of America and Univ of Kansas press, R.C. Moore (ed) {{Taxonbar, from=Q7507032 Nautiloids