(Yandu lizard - Yandu is the old name for Zigong, a city in
Sichuan Province, China).
Named By: X. He - 1979.
Classification: Chordata, Reptilia, Dinosauria, Ornithischia, Ornithopoda.
Species: Y. hongheensis (type).
Size: At least three meters long for the holotype, possibly as much as somewhere between 3.5 and 4 meters.
Known locations: China, Sichuan Province - Lower Shaximiao Formation.
Time period: Bathonian of the Jurassic.
Fossil representation: Skull and partial post cranial skeleton.
a Chinese construction site in 1973 a dinosaur skeleton was
accidentally processed by a mechanical composter. Unfortunately
by the time the workers had realised what had happened much of the
dinosaur had already been damaged and in some places completely
destroyed by the machinery, but palaeontologists were still able to
reconstruct and identify a new genus of dinosaur.
Yandusaurus was a small bipedal dinosaur that was superficially similar to most of the small ornithischian dinosaurs (such as Hypsilophodon) that were running about during the Mid Jurassic. Despite significant damage to the holotype individual, we know that Yandusaurus had five fingered hands and four toed feet. With a length of at least three meters, Yandusaurus was already quite large for an ornithischian dinosaur of its kind, but still would have relied upon a combination of speed and agility to try and evade the jaws of predators.
In 1983 a second species of Yandusaurus was named as Y. multidens, and represented by the fossil remains of about nine different individuals in varying states of completeness. However these individuals have since been determined to not represent a new species of Yandusaurus. Since this realisation Y. multidens has been re-classified as species of Agilisaurus (Peng, 1992) and Othnielia (Paul, 1996), before finally being described as a distinct genus in 2005 (Barrett et al).
- A newly discovered ornithopod dinosaur Yandusaurus from Zigong, Sichuan, by X. He - In, Contributions to International Exchange of Geology. Part 2. Stratigraphy and paleontology. Geol. publishing House, Beijing: pp. 116-123. - 1979.
- A new species of Yandusaurus (hypsilophodont dinosaur) from the Middle Jurassic of Dashanpu, Zigong, Sichuan. - Journal of Chengdu College of Geology Supplement 1: 5-14. - X. -L. He, K. -J. Cai - 1983.
- The Middle Jurassic dinosaur fauna from Dashanpu, Zigong, Sichuan. Vol. I. The ornithopod dinosaurs. - Sichuan Scientific and Technological Publishing House, Chengdu 1-71.- X. He & K. Cai - 1984.
Small-bodied ornithischian dinosaurs from the Middle Jurassic of Sichuan, China. - Journal of Vertebrate Paleontology 25(4):823-834. - P. M. Barrett, R. J. Butler & F. Knoll - 2005.