Brevicoceratidae Temporal range:
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | Nautiloidea |
Order: | †Oncocerida |
Family: | †Brevicoceratidae Flower, 1941 |
The Brevicoceratidae is a family of oncocerids that contains genera characterized by exogastric (or rarely endogastric) gyrocones, brevicones, and torticones.[1][2] that tend to develop vestigial actinosiphonate deposits and subtriangular transverse sections. The Brevicoceratidae are derived from Oonoceras (Oncoceratidae) and range from the mid-Silurian to the Upper Devonian.[2]
Brevicoceratidae is named for the Middle Devonian genus, Brevicoceras, from North America.[2] All told there are some 17 named genera. The family begins with Oxygonioceras in the Middle Silurian,[2] sole recognized representative of that time, and reaches its greatest diversity with 12 genera in the Middle Devonian.[2] The Brevicoceratidae are reduced to four genera in the Upper Devonian, when they become extinct.