Siberionautilidae
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.
| Siberionautilidae | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | Nautiloidea |
| Order: | Nautilida |
| Superfamily: | †Clydonautiloidea |
| Family: | †Siberionautilidae Popov, 1951 |
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)