Szechuanosaurus

*Szechuanosaurus campi*

***Szechuanosaurus campi*** (Greek for "Szechuan lizard") is a dubious genus of carnivorous theropod dinosaur from the Late Jurassic. Fossils referred to the genus have been found in Asia in the Oxfordian and early Kimmeridgian. It resembled a small *Allosaurus*, with a weight of 100 - 150 kilograms (220 - 330 lb) and a length of 8 meters (27 ft).

## Discovery and species

Three species have been assigned to this genus over the years. The type species is *Szechuanosaurus campi*, named by Yang Zhongjian ("Chung Chien Young") in 1942 for four isolated tooth specimens: IVPP V235, two partial teeth; IVPP V236, a partial tooth; IVPP V238, several tooth fragments; and IVPP V239, a single tooth. The teeth form a syntype series and were not found together. Also a very fragmentary skeleton, specimen UCMP 32102, was referred to the genus by Yang. Some of the teeth indicate a large body-size. These fossils, although possibly sinraptorid, are now considered to be non-diagnostic, making *S. campi* a *nomen dubium*. The generic name refers to Szechuan. The specific name honours the American paleontologist Charles Lewis Camp who had discovered UCMP 32102.

A partial skeleton, CV 00214, was initially listed by Dong *et al.* (1978) in a faunal list as a new species of *Szechuanosaurus*, *Szechuanosaurus yandonensis*. At first, there was no description or illustration of it, making *S. yandonensis* at the time a *nomen nudum*. Later, Dong Zhiming *et alii* (1983) described it, and assigned it to *Szechuanosaurus campi* The affinities of this skeleton are uncertain, and it has only been briefly described. Holtz *et al*. (2004) included it in their phylogenetic analysis and found it to be the most basal tetanuran. This individual was a medium-sized theropod, with an ischium (a pelvic bone) of 420 millimetres (17 in); for comparison, an ischium of *Piatnitzkysaurus* estimated to weigh 504 kilograms (1,111 lb) is 423 millimetres (16.7 in) long. In 2000, Daniel Chure referred the specimen to "Szechuanoraptor dongi", itself an invalid *nomen ex dissertatione*. Carrano, Benson & Sampson (2012) synonymized it with *Yangchuanosaurus shangyouensis* from the same formation.

The third species is *Szechuanosaurus zigongensis*, named by Gao Yuhui in 1993 for an almost complete skeleton, specimen ZDM 9011. It is an older species, from the Middle Jurassic, appearing to be distinct from the type species and therefore requires its own genus name. It was reassigned to *Yangchuanosaurus*, as a *Yangchuanosaurus zigongensis*, by Matthew Carrano, Roger Benson & Scott Sampson in 2012.

## JPInstitute.com Description

Szechuanosaurus was a medium-sized meat-eater that lived in China and was related to Allosaurus. Since the only parts of its head that have been found are a few teeth, scientists aren't exactly sure what it looked like. Fortunately, most of its body has been discovered so its size and family relationship can be determined. This dinosaur would have been one of the top predators of its time in the late Jurassic.

Originally founded on just a few teeth discovered in 1915, this dinosaur has been debated within China for some years. The current skull restoration is not considered accurate by many researchers.

## Links

http://web.archive.org/web/20040214170207fw\_/http://www.jpinstitute.com/dinopedia/dinocards/dc\_szechuanosaurus.html

## References

1. https://web.archive.org/web/20130929081120/http://archosaur.us/theropoddatabase/Neotheropoda.htm#Szechuanosauruscampi