YANGCHUANOSAURUS (yang-choo-AHN-oh-SORE-us)
Period: Late Jurassic
Order, Suborder, Family: Saurischia, Theropoda, Allosauridae
Location: Asia (People's Republic of China)
Length: Estimated 30 feet (9 meters)
Until 1976, we only knew the predatory dinosaurs of China from teeth and pieces of fossil bones. Then a construction worker in Yangchuan County found the first nearly complete skeleton of an Allosaurus-size meat-eater while digging the foundation for the Shangyou dam.
When scientists studied the skeleton, only its small forelimbs and the back half of its tail were missing. In 1978, a group of Chinese paleontologists named the dinosaur Yangchuanosaurus shangyouensis. Museum workers prepared and mounted its skeleton at the Chongqing Municipal Museum.
Since the first find, workers have discovered a much larger Yangchuanosaurus skeleton nearby. It has been described as a second species, Y. magnus. With a skull over three feet long, it is the largest Late Jurassic theropod known from China. Many paleontologists think it is a fully grown Y. shangyouensis, because it was in rocks of the same age. It differs from the original species because it is larger and has more fully developed bones. Yangchuanosaurus seems closely related but is more primitive than Allosaurus from North America; scientists classify it in the family Allosauridae.
Like many predatory dinosaurs, Yangchuanosaurus had a low crest that ran along the front of its snout, from the nose to slightly in front of the eyes. In life, the crest probably had a horny covering. It may have been brightly colored to attract a mate. Yangchuanosaurus almost certainly hunted the plant-eaters of its day, including the stegosaur Chungkingosaurus.
