Huayangosaurus
| Huayangosaurus | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Skeletal reconstruction of Huayangosaurus |
||||||||||||
| Temporal occurrence | ||||||||||||
| Middle Jurassic ( Bajocium ) | ||||||||||||
| 170.3 to 168.3 million years | ||||||||||||
| Locations | ||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name of the family | ||||||||||||
| Huayangosauridae | ||||||||||||
| Dong, Tang & Zhou, 1982 | ||||||||||||
| Scientific name of the genus | ||||||||||||
| Huayangosaurus | ||||||||||||
| Dong , Tang & Zhou , 1982 | ||||||||||||
| Art | ||||||||||||
|
||||||||||||
Huayangosaurus is a genus of bird's pelvis dinosaur (Ornithischia) from the group of stegosauria . It is one of the oldest known stegosauria and systematically occupiesa special position in this group.
features
Huayangosaurus reached a length of around 4.5 meters and, like all stegosaurs, was characterized by a double row of bone plates along the back and tail, the function of which ( thermoregulation , courtship behavior , defense against enemies or a combination of these tasks) has not finally been clarified. In addition, it had a spike over each shoulder blade, and the tail also had two pairs of long, pointed spikes at the end.
As the only representative of the Stegosauria, it had at least one row of horn scales on each side of the trunk . In contrast to the other stegosauria, the front legs were only slightly shorter than the rear legs.
As with all stegosauria, the teeth were small and designed for plant food. Huayangosaurus was the only stegosaur to wear a small horn over each eye and also had teeth in the front part of the snout - on the premaxillary . In general, the snout of these animals was shorter and taller than that of the other stegosauria.
Discovery and naming
Fossils of Huayangosaurus was in the Shaximiao lineup in the Chinese province of Sichuan discovered and 1982 by Dong Tang and Zhou described . The name is derived from "Hua Yang", an old name of the Sichuan province. A complete skeleton including skull and the partially preserved remains of five other animals were found. The finds were dated to the Middle Jurassic ( Bajocium ).
Systematics
Due to its morphological peculiarities, Huayangosaurus has a special role within the stegosauria and is managed in its own family, Huayangosauridae. Phylogenetically , it is considered to be the sister taxon of the other stegosauria, which are grouped together in the family of the Stegosauridae.
literature
- 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 .
- David E. Fastovsky , David B. Weishampel: The Evolution and Extinction of the Dinosaurs. 2nd edition. Cambridge University Press, Cambridge et al. 2005, ISBN 0-521-81172-4 .