Yangchuanosaurus (Greek for "Yangchuan lizard"); pronounced yang-chwan-oh-SORE-us
Woodlands of Asia
Late Jurassic (155-145 million years ago)
Size and Weight:
About 25 feet long and 2-3 tons
Large size; long tail; bony ridges on face
For all intents and purposes, Yangchuanosaurus filled the same niche in late Jurassic Asia as its fellow large theropod, Allosaurus, did in North America: an apex predator that harassed the numerous sauropods and stegosaurs of its lush ecosystem. The 25-foot-long, two- to three-ton Yangchuanosaurus possessed an especially long, muscular tail, as well as distinctive ridges and decorations on its face (which were similar to those of a smaller theropod, Ceratosaurus, and may have been brightly colored during mating season). One prominent paleontologist has suggested that Yangchuanosaurus may be the same dinosaur as Metriacanthosaurus, but not everyone is convinced.