Onychodontiformes
| Onychodontiformes | ||||||||||||
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Artistic reconstruction of the life of Onychodus |
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| Temporal occurrence | ||||||||||||
| Devon | ||||||||||||
| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Onychodontiformes | ||||||||||||
| Andrews , 1973 |
The Onychodontiformes (= Onychodontida, = Onychodontidae, = Struniiformes) are a little-researched, extinct group of bony fish from the class of the meat fins (Sarcopterygii). They lived in the Middle and Upper Devonian . It is possible that these animals are not a systematic group ( taxon ), but a paraphyletic group of basal meat fins.
The Onychodontiformes were first known from small forms such as Strunius from Germany, as well as from skull fragments, jaws and single bones belonging to Onychodus . Fully preserved specimens of Onychodus up to two meters long were later discovered in the Gogo Formation in Western Australia.
Characteristic of the Onychodontiformes were large "fangs" in the front part of the lower jaw, as well as a very flexible skull , which probably made it possible for the fish to swallow very large prey whole. A partially preserved skull of Onychodus from the Gogo formation contains the bones of a small placoderma approximately 30 centimeters long in the throat region, which was swallowed tail first.
The upper jaw ( maxilla ) of the Onychodontiformes resembles that of the ray fins .
Genera
- Psarolepis
- Bukkanodus
- Onychodus
- Strunius
Psarolepis romeri from the lowest Devonian is probably the primitive sister group of all other Onychodontiformes.
literature
- Joseph S. Nelson : Fishes of the World. John Wiley & Sons, 2006, ISBN 0-471-25031-7 .
- John A. Long: The Rise of Fishes . Johns Hopkins University Press , 1995, ISBN 0-8018-4992-6 .
Web links
- Palæos Onychodontiformes