Wannanosaurus
| Wannanosaurus | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Temporal occurrence | ||||||||||||
| Upper Cretaceous (early Maastrichtian ) | ||||||||||||
| 72 to 69.9 million years | ||||||||||||
| Locations | ||||||||||||
| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Wannanosaurus | ||||||||||||
| Hou , 1977 |
Wannanosaurus is a genus of the bird pelvic dinosaur (Ornithischia) from the group of the Pachycephalosauria . The only species described is W. yansiensis .
features
From Wannanosaurus the remains were found so far of two animals, known parts of the skull, the lower jaw, parts of the basin as well as individual limb bones. The roof of the skull was flat and the fenestra supratemporalis (the upper cranial window of the temporal region ) strongly pronounced, making this dinosaur resemble other flat-headed pachycephalosaurs such as Homalocephale . Wannanosaurus are characterized by the low, fan-shaped tooth crowns and the strong curvature of the thigh bone. The findings suggest a very small animal, probably only around 0.6 meters in length, but it may have been young animals. Like all pachycephalosaurs , Wannanosaurus was probably a two-legged, probably more herbivorous dinosaur. For the function of the thickened skullcap, see Function of the skullcap in the Pachycephalosauria .
Discovery and systematics
The fossil remains of Wannanosaurus were in Xiaoyan lineup in the Chinese province of Anhui found and first described in 1977th The genus name is derived from the place where it was found, the only known species and thus type species is W. yansiensis . The 72 to 69 million years dated.
Wannanosaurus is considered to be the original representative of the Pachycephalosauria. A cladistic study by T. Maryańska et al. saw in him the sister group of all the other Pachycephalosauria grouped together as Goyocephala. However, due to the scarce remains, such results are controversial.
literature
- Teresa Maryańska , Ralph E. Chapman, David B. Weishampel : Pachycephalosauria. In: David B. Weishampel, Peter Dodson , Halszka Osmólska (eds.): The Dinosauria . 2nd edition. University of California Press, Berkeley CA et al. 2004, ISBN 0-520-24209-2 , pp. 464-477.
- Robert M. Sullivan: A taxonomic review of the Pachycephalosauridae (Dinosauria: Ornithischia). In: Spencer G. Lucas, Robert M. Sullivan (Eds.): Late Cretaceous Vertebrates from the Western Interior (= New Mexico Museum of Natural History and Science. Bulletin. 35, ISSN 1524-4156 ). New Mexico Museum of Natural History and Science, Albuquerque NM 2006, pp. 347–365, digital version (PDF; 4.79 MB) .