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".