Uranoceratidae
Uranoceratidae | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
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:
References
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