Tuojiangosaurus

*Tuojiangosaurus multispinus*

***Tuojiangosaurus*** is a genus of Stegosaurid dinosaur from the Late Jurassic Period, recovered from the Upper Shaximiao Formation of what is now Sichuan Province in China.

## Description

Physically similar to the North American Stegosaurus, Tuojiangosaurus is the best understood of the Chinese stegosaurids. The only known species is ***T. multispinus***, named in 1977. The Tuojiangosaurus, like the Stegosaurus, has plates along its back imbedded in its skin and four spikes on its tail, probably used to defend itself against predators such as the Yangchuanosaurus. But the plates are triangular(Stegosaurus' plates are pentagonal), and the longest plates were on its hip. It also have a small head, a big body and low teeth like other stegosaurids.

## Discovery

The type and only species, *T. multispinus*, was named in 1977 (exactly a hundred years after *Stegosaurus*) on the strength of two specimens, one over half complete. A mounted skeleton of *Tuojiangosaurus multispinus* is on display at the Municipal Museum of Chongqing. In addition, a mounted cast is on display at the Natural History Museum, in London.

## Classification

*Tuojiangosaurus* was by Dong placed in Stegosauridae in 1977, more precisely in the Stegosaurinae. In 2004, a cladistic analysis by Galton recovered *Tuojiangosaurus* in a rather derived position, as a sister species of *Chialingosaurus*. An analysis by Octávio Mateus, Maidment, and Nicolai Christiansen, published in 2009, found that *Tuojiangosaurus* fell outside of Stegosauridae, though its exact position in Stegosauria (either as an early branching member of the group or a later branching species closer to stegosaurids) was uncertain due to the relatively fragmentary nature of the remains. A more comprehensive analysis by Raven and Maidment in 2017 found that it grouped with *Huayangosaurus* and its relatives.

## Paleobiology

While early depictions of stegosaurids saw these plates as being for either defence or thermoregulation,‭ ‬modern analysis has found the plates to‭ ‬not‭ ‬really be suitable for either of these purposes.‭ ‬The plates themselves are too weak and brittle to protect against a powerful bite,‭ ‬and not adapted enough for an efficient thermoregulation purpose.‭ ‬This leaves the explanation of inter species display where stegosaurids could recognise others of their‭ ‬kind by the shape and arrangement of the plates which differed between individual genera and species. Because it lacked the tall spines for muscle attachment found on the vertebrae of Stegosaurus, it was probably unable to rear up on its hind legs like that animal. This suggests that it would have eaten low-lying, ground vegetation.

## JPInstitute.com Description

Tuojiangosaurus is the best known member of the stegosaur family that has been found in China. This plant eater looked a lot like its better known North American relative, Stegosaurus. The most obvious difference is that the plates along its back are smaller that those on Stegosaurus. These dinosaurs were designed to eat plants that grew low to the ground. The long, sharp spikes on its tail would have been a powerful weapon against attackers.

First discovered in 1974 in the fossil-rich Zigong area of China, Tuojiangosaurus is known from two specimens, one of which was more than 50% complete. The plates along its back form two distinct rows and are much smaller and more pointed that those of Stegosaurus. It shares a number of similarities with another African stegosaur, Kentrosaurus , including pointed spike-like plates above its shoulders.

## Appearance in other media

### *Jurassic Park*

* It appears in all of Ludia's Jurassic Park games, Jurassic Park Builder, Jurassic World: Alive, and Jurassic World: The Game.

## Links

https://web.archive.org/web/20080527155631/http://kids.yahoo.com/dinosaurs/426--Tuojiangosaurus

## References

1. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Dong1977`
2. ↑ Cite error: Invalid `<ref>` tag; no text was provided for refs named `Galton2004`
3. ↑ Mateus, Maidment and Christiansen (2009). "A new long-necked ‘sauropod-mimic’ stegosaur and the evolution of the plated dinosaurs", *Proc Biol Sci. 2009 May 22; 276(1663): 1815–1821.*
4. ↑ Template:Cite journal