Yangchuanosaurus by Moondawg

Yangchuanosaurus was a theropod dinosaur that lived in China during the Late Jurassic period, and was similar in size and appearance to its North American contemporary, Allosaurus.

It hails from the Upper Shaximiao Formation and was the largest predator in a landscape which included the sauropods Mamenchisaurus and Omeisaurus as well as the Stegosaurs Chialingosaurus, Tuojiangosaurus and Chungkingosaurus

In 1976, an almost complete skeleton of what was to be named Yangchuanosaurus shangyouensis was uncovered by a construction worker during the construction of the Shangyou Reservoir Dam in Yangshuan County in Sichuan Province. Since then further skeletons have been recovered.

Yangchuanosaurus shangyouensis reached about 7 metres long (23 ft) and had a skull around 80 cm long (32 in). Its relative Y. magnus grew larger still; up to 10 metres long (33 ft), with a skull up to 1 metre (3 ft) in length. There was a bony knob on its nose and multiple hornlets and ridges, similar to Ceratosaurus. It had a massive tail that was about half its length.

The original skeleton of Yangchuanosaurus shangyouensis is on display at the Municipal Museum of Chongqing, as is some material of Y. magnus. Another, recovered from Xuanhan County in Sichuan, is on display in the Beijing Museum of Natural History.