Tuojiangosaurus

Tuojiangosaurus multispinus is one of the most complete Asian stegosaurs and a prominent member of the family in China. The name multispinus, meaning "many spines," refers to its unique dorsal armament. It possessed about 15 pairs of pointed, conical plates that ran from its neck to its tail. These structures were narrower than the kite-shaped plates of Stegosaurus, representing a shape halfway between a true plate and a spike.

This stegosaur was medium-sized, reaching about 7 m in length and weighing around 2.8 tonnes. It featured the characteristic stegosaurian build: high hips, a low-slung head, and a narrow skull with a beak and leaf-shaped teeth. Its hindlimbs were notably longer than its forelimbs. At the end of its tail was a thagomizer consisting of four defensive spikes. While its body plan was similar to that of its North American relatives, it was slightly more gracile.

A second named species, T. junggarensis, was found in the Junggar Basin, though some researchers argue it may belong to a separate genus.

Tuojiangosaurus shared its humid floodplain habitat with the long-necked sauropod Mamenchisaurus and the predator Gasosaurus. The Shaximiao Formation supported a rich environment of ferns, cycads, and horsetails, which sustained low-level browsers. Its pointed plates likely functioned for display, species recognition, and potentially heat regulation, similar to other stegosaurs. The spikes on its tail were used as a weapon for defense.

Biomechanical studies of its skull and analysis of its tooth wear indicate that this dinosaur was a specialist in eating low-growing vegetation. Its diet likely consisted of ferns, cycads, and perhaps low-lying conifer needles.

• CV 209 — holotype, Chongqing Natural History Museum.
• Multiple Zigong specimens — Zigong Dinosaur Museum, Sichuan; impressive mounts.
• Natural History Museum of London cast — common touring/exhibition replica.

Plate function — display + species recognition + thermoregulation, similar to other stegosaurs. Plate-vs-spike intermediate morphology — the pointed-plate condition has been argued to represent either a plesiomorphic state or a derived Asian innovation. Phylogenetic position — well-resolved within Stegosauridae but precise relationship to Stegosaurus and Kentrosaurus contested across analyses.

Tuojiangosaurus features prominently in Chinese dinosaur museum exhibits, particularly Zigong, and in many international dinosaur reference works. It is one of the most-recognised Asian stegosaurs.

• stegosauria
• stegosaurus
• kentrosaurus
• mamenchisaurus

• Dong, Z., Li, X., Zhou, S., & Zhang, Y. (1977). On the dinosaurian remains from Wuerho, Xinjiang. Vertebrata PalAsiatica, 15, 53–60.
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• Galton, P. M., & Upchurch, P. (2004). Stegosauria. In The Dinosauria (2nd ed.).