Uranoceratidae
Extinct family of molluscs
Uranoceratidae Temporal range: ?Late Ord - Mid Sil | |
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Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | Nautiloidea |
Order: | †Tarphycerida |
Suborder: | †Barrandeocerina |
Family: | †Uranoceratidae Hyatt in Zittel, 1900 |
Genera | |
See text |
The Uranoceratidae is a family of Silurian barrandeoceroids that tend to become uncoiled with age and in which siphuncle segments tend to be expanded into the camerae.[1]
Description
Shells of uranoceratids are gyroconic. Early stages of a few species are annulated. Later stages of all are smooth or faintly striated or cancellated.[2] In many, septal necks are straight, but in others recumbent on one side or the other. Connecting rings are thin.
Derivation and content
The Uranoceratidae are derived from Bickmorites.[1] Genera include:
- Uranoceras
- Jolietoceras
- Cumingsoceras, and
- Cliftonoceras.[2]
References
- ^ a b Flower, R.H. & Kummel, B. 1950. A Classification of the Nautiloidea. Journal of Paleontology vol 24, no.5, pp604–616, Sept 1950.
- ^ a b Sweet, Walter C, 1964. Nautiloidea - Barrandeocerida, in Treatise on Invertebrate Paleontology, Part K, Geol Soc of America, Teichert & Moore(eds).