Tuojiangosaurus

Tuojiangosaurus

Tuojiangosaurus (meaning "Tuo River lizard") was a plant-eating dinosaur that lived a very long time ago during the Late Jurassic Period. It was part of a group of dinosaurs called stegosaurians. These dinosaurs had bony plates on their backs and spikes on their tails. Fossils of Tuojiangosaurus were found in Sichuan Province in China, in rocks called the Upper Shaximiao Formation. Learning about this dinosaur helps scientists understand more about the amazing creatures that lived millions of years ago.

Description

Tuojiangosaurus was a large stegosaur that grew to be about 6.5 metres (21 feet) long and weighed around 2.8 metric tons (3.1 short tons). It looked very similar to the North American Stegosaurus, and it is one of the best-known stegosaurs from China.

Tuojiangosaurus had a narrow head, strong body, and low teeth like other stegosaurs. Its legs, especially the front ones, were shorter. It had at least twenty-five teeth in its lower jaw, and these teeth had thick bases. Like Kentrosaurus, Tuojiangosaurus had two rows of plates along its back. These plates became taller near the hips. The plates on the neck and front part of the body were rounded or pear-shaped, while those on the back were more triangular and pointed. Unlike Stegosaurus, the plates of Tuojiangosaurus stood straight up next to each other. Each end of its tail had at least two strong spikes pointing outward at about a 45-degree angle. In stegosaur families, this arrangement of spikes is playfully called the "thagomizer".

Discovery

In 1974, workers building a dam in Zigong, Sichuan, found the bones of a stegosaurian dinosaur.

The dinosaur, named Tuojiangosaurus multispinus, was described in 1977 by scientists Dong Zhiming, Zhou Shiwu, Li Xuanmin, and Chang Yijong. The name comes from the Tuo River, where the dinosaur's bones were found. The fossil is one of the most complete stegosaurian skeletons found in Asia. It is missing some parts like the skull and tail. A model of this dinosaur can be seen at museums in Chongqing, London, and Beijing.

Classification

Tuojiangosaurus was a member of the Stegosauridae family. In 2004, scientists found it was closely related to Chialingosaurus. A study in 2009 could not say exactly where it fit in the group because the fossils were incomplete. A study in 2017 showed it was related to Huayangosaurus and similar dinosaurs.

Paleobiology

Tuojiangosaurus was a plant-eater. It ate low plants and grass on the ground. Some scientists, like Paul, think that two other dinosaurs, Chialingosaurus and Chungkingosaurus, might have been young Tuojiangosaurus.