Uranoceratidae
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]
| Uranoceratidae | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | Nautiloidea |
| Order: | †Tarphycerida |
| Suborder: | †Barrandeocerina |
| Family: | †Uranoceratidae Hyatt in Zittel, 1900 |
| Genera | |
|
See text | |
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:
References
- Flower, R.H. & Kummel, B. 1950. A Classification of the Nautiloidea. Journal of Paleontology vol 24, no.5, pp604–616, Sept 1950.
- Sweet, Walter C, 1964. Nautiloidea - Barrandeocerida, in Treatise on Invertebrate Paleontology, Part K, Geol Soc of America, Teichert & Moore(eds).
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