Yangchuanosaurus

Yangchuanosaurus was a genus of theropod dinosaur from the Jurassic of China. It was a fairly typical carnosaur, with a large head, sharp, serrated teeth, and relatively short arms (though not as short as those of "Tyrannosaurus"). It was the largest predator in its part of the world. "Yangchuanosaurus" probably preyed on sauropods, such as "Mamenchisaurus", or stegosaurs, such as "Tuojiangosaurus".
There are two species. "Y. zigongensis" is from the Middle Jurassic, and "Y. shangyouensis" is from the Upper Jurassic. Specimens were collected from the Dashanpu Dinosaur Quarry of Zigong, Sichuan.
The Middle Jurassic "Y. zigongensis" is known from four incomplete specimens. There are two specimens of the Upper Jurassic "Y. shangyouensis", which were at first put into separate species. Later analysis showed they were probably different ages or variations of the same species.
The first skull is 82 cm (2.7 ft) long, and its total body length about 8 m (26 ft). The other specimen was even larger. It had a skull length of 1.11 m (3.6 ft). It may have been up to 10.8 m (35.4 ft) long, and weighed as much as 3.4 metric tons (3.7 short tons). 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.