Chondrosteidae
| Chondrosteidae | ||||||||||||
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Chondrosteus acipenseroides , fossil in the Teylers Museum, Haarlem . |
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| Temporal occurrence | ||||||||||||
| Lower Jurassic to Lower Cretaceous | ||||||||||||
| Locations | ||||||||||||
| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Chondrosteidae | ||||||||||||
| Egerton , 1858 |
The Chondrosteidae are a family of extinct primitive bony fish from the order of the sturgeon-like (Acipenseriformes). Only two safe genera are known, Chondrosteus from the Lower Jurassic of Europe and Strongylosteus from the Lower Cretaceous of Central Asia . Another genus, the 5 meter long Gyrosteus from the Jura of England, could also be a Chondrosteid.
features
The Chondrosteidae were medium-sized to very large fish (0.5 to 3 meters) that had a plump, stocky body than today's sturgeon species. Except for the caudal peduncle and the upper lobe of the heteroccal caudal fin, her body was bare. The lower caudal fin lobe was relatively large and wider than the upper one. The head was broad, the rostrum somewhat elongated and pointed. The mouth was submissive . The dorsal, ventral and anal fins were located in the rear half of the body, the anal fin still at an angle behind the dorsal fin.
Systematics
The Chondrosteidae are the more primitive fossil sister group of all recent sturgeon species.
literature
- Joseph S. Nelson : Fishes of the World. John Wiley & Sons, 2006, ISBN 0-471-25031-7 .
- Karl Albert Frickhinger: Fossils Atlas Fish , Mergus-Verlag, Melle, 1999, ISBN 3-88244-018-X .
Individual evidence
- ↑ Michael J. Benton : Paleontology of the vertebrates. Page 187, 2007, ISBN 3-89937-072-4