Science, Tech, Math › Animals & Nature Tuojiangosaurus Share Flipboard Email Print The spiked tail of Tuojiangosaurus (American Museum of Natural History). Animals & Nature Dinosaurs Herbivores Basics Paleontologists Carnivores Dinosaurs & Birds Marine Reptiles Prehistoric Mammals Amphibians Birds Habitat Profiles Mammals Reptiles Wildlife Conservation Insects Marine Life Forestry Evolution View More By Bob Strauss Science Writer B.S., Cornell University Bob Strauss is a science writer and the author of several books, including "The Big Book of What, How and Why" and "A Field Guide to the Dinosaurs of North America." our editorial process Bob Strauss Updated March 17, 2017 Name: Tuojiangosaurus (Greek for "Tuo river lizard"); pronounced TOO-oh-jee-ANG-oh-SORE-us Habitat: Woodlands of Asia Historical Period: Late Jurassic (160-150 million years ago) Size and Weight: About 25 feet long and four tons Diet: Plants Distinguishing Characteristics: Long, low skull; four spikes on tail About Tuojiangosaurus Paleontologists believe stegosaurs--the spiked, plated, elephant-sized herbivorous dinosaurs--originated in Asia, then crossed over to North America during the late Jurassic period. Tuojiangosaurus, a near-complete fossil of which was found in China in 1973, appears to be one of the most primitive stegosaurs yet known, with anatomical features (lack of tall vertebral spines toward its rear end, teeth in the front of its mouth) not seen in later members of this breed. However, Tuojiangosaurus did retain one very characteristic stegosaur feature: the four paired spines at the end its tail, which it presumably used to inflict damage on the hungry tyrannosaurs and large theropods of its Asian habitat.