The upstream Yongchuan dragon is a large carnivorous dinosaur that lived in the Late Jurassic 180 million to 150 million years ago, found in the reservoir dam near the upper reaches of Yongchuan in Chongqing, hence the name. The fossil found at that time was an almost complete skeleton containing a skull, which is very precious.
There are many openings in the yongchuan dragon head bone, which can not only reduce the weight of the skull, but also make the muscles on the head shrink into the hole when hunting, which is conducive to opening the mouth. At the same time, the neck becomes short and thick, making it easy to lift the head. The mouth was full of rows of sharp teeth, like a dagger, its forelimbs had sharp claws, and it could firmly grasp its prey, just like the American tyrannosaurus, they were large predators in the Yongchuan region at that time, and the Hechuan Mamenxi dragon that lived in the same period as them was often their meal.