Onychodontida

Artistic reconstruction of live Onychodus

The Onychodontiformes ( = Onychodontida, = Onychodontidae, = Struniiformes ) are a little-known, extinct group of bony fish from the class of meat -finned fishes ( Sarcopterygii ). They lived in the Middle and Upper Devonian. It is possible that in these animals is not a systematic group ( taxon ) but a paraphyletic group of basal -finned meat.

The Onychodontiformes were known initially of small forms such as Strunius from Germany, as well as belonging to Onychodus skull fragments, jaw, and individual bones. Later, up to two meters long specimens of Onychodus were completely preserved, discovered in the Gogo Formation of Western Australia.

Characteristic of the Onychodontiformes were large " fangs " in the front part of the lower jaw, and a very flexible skull, which it probably allowed the fish to swallow very large prey whole. A partially preserved skull of Onychodus from the Gogo Formation in the fillet region contains the bones of a small, about 30 centimeters long Placodermen, which was swallowed up by the tail first.

The upper jaw (maxilla ) of Onychodontiformes similar to the ray-finned fishes.

Genera

  • Psarolepis
  • Bukkanodus
  • Onychodus
  • Strunius

Psarolepis Romeri from the lowest Devon is probably the primitive sister group of all other Onychodontiformes.

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