Canowindridae
| Canowindridae | ||||||||||||
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Fossil of Gyroptychius agassizi |
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| Temporal occurrence | ||||||||||||
| Middle of Devon ? to Famennium (Upper Devonian) | ||||||||||||
| ? up to 358.9 million years | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Canowindridae | ||||||||||||
| Young , Long & Ritchie , 1992 |
The Canowindridae are an extinct fish family of the meat fin fish (Sarcopterygii), which occurred from the Middle Devon to the Upper Devon . Fossils of the family have been found in southeastern Australia (states of New South Wales and Victoria ) and in one of the Antarctic dry valleys in Victoria Land in East Antarctica . The assignment of Gyroptychius from Europe and Greenland is uncertain.
features
The Canowindridae had very wide and flat heads, parietal bones , intertemporal and supratemporal (temporal = temple bones ) could have grown together. The extrascapulare, another cranial bone, had a wide rear and a narrow front end. The cheekbone was twice as long as it was high. The main postorbital bone was short, out of contact with the edge of the orbit and separated from it by several small bones. The eyes, which are very small in all Canowindridae, are probably a symplesiomorphic feature and also occurred in the Porolepiformes . The gill covers were large. In the family there were both original, rhombic-shaped cosmoid scales and, in Canowindra , round scales with a central protrusion on the inside and without cosmin , as in the Tristichopteridae .
Genera
- Beelarongia , Long, 1987 (Victoria, Australia)
- Canowindra M'Coy, 1848 (New South Wales, Australia)
- Gyroptychius , Smith, 1939 (Europe, Greenland), (assignment uncertain)
- Koharolepis , Young, Lo & Ritch, 1992 (Antarctica)
- Marsdenichthys , Long, 1985 (Victoria)
Systematics
The Canowindridae are assigned to the Osteolepiformes , a meat-finisher group that is now considered paraphyletic .
The systematic position shows the following cladogram:
| Tetrapodomorpha |
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literature
- Gavin C. Young, John A. Long & A. Ritchie, 1992: Crossopterygian fishes from the Devonian of Antarctica: systematics, relationships and biogeographic significance. Records of the Australian Museum, doi : 10.3853 / j.0812-7387.14.1992.90
Individual evidence
- ^ Brian Swartz: A Marine Stem-Tetrapod from the Devonian of Western North America. PLoS doi : 10.1371 / journal.pone.0033683
Web links
- Palaeos: Canowindridae