Туоцзянгозавр: китайский стегозавр юрского периода

Extinct genus of dinosaurs

Tuojiangosaurus (meaning "Tuo River lizard") is a genus of herbivorous stegosaurian dinosaur from the Late Jurassic Period, recovered from the Upper Shaximiao Formation of what is now Sichuan Province in China.

Tuojiangosaurus was a large stegosaur, reaching in length and in body mass. Physically similar to the North American Stegosaurus, Tuojiangosaurus is the best understood of the Chinese stegosaurs. In 1977, Dong provided a diagnosis but this largely consisted of traits shared with other stegosaurus. In 1990, Peter Malcolm Galton pointed out an autapomorphy: the spines of the vertebrae of the tail base possess spines with bony skirts running from their front to the sides. Tuojiangosaurus has the typical narrow and low head, bulky body, and low teeth of other stegosaurids. The limbs, especially the arms, are rather short. There are at least twenty five dentary teeth. The teeth have a thick base, cingulum, merging at the inside into a triangular vertical median ridge. The dorsal vertebrae have tall neural arches. The shoulder blade has a rectangular acromion. Like Kentrosaurus, Tuojiangosaurus had two rows of plates along the spine, which became taller over the hip region. Those at the neck and front trunk were rounded or pear shaped; the plates at the rear back became more triangular and pointed. All plates have a thickened central section, as if they were modified spikes. The holotype, CV 209, was found in a layer of the Upper Shaximiao Formation, dating from the Oxfordian Kimmeridgian. It consists of a rather complete skeleton that however lacks parts of the skull, lower jaws, tail and limbs. In 1977, it represented the most complete stegosaurian skeleton found in Asia. The paratype was specimen CV 210, a sacrum. A more comprehensive analysis by Raven and Maidment in 2017 found that it grouped with Huayangosaurus and its relatives.

Tuojiangosaurus ate low lying, ground vegetation. Paul suggested that Chialingosaurus and Chungkingosaurus were in fact the juveniles of Tuojiangosaurus.