Here are some new exciting findings in fossil treasure, the Dinosaur Fauna in Yunyang County, Chongqing. A new genus and species of plant-eating dinosaur, Bashanosaurus primitivus, was discovered in Chongqing, announced Chongqing Municipal Bureau of Planning and Natural Resources on March 7. According to the results of stratigraphic research, Bashanosaurus primitivus lived 169 million years ago, which makes it currently the oldest stegosaurus fossil in Asia. "Bashanosaurus primitivus is the earliest record of Stegosauria in Asia and represents one of the earliest records of this dinosaur group from anywhere in the world." Sci-News reported it on March 3.

The restored figure of Bashanosaurus primitivus. (Photo/ Chongqing Municipal Bureau of Planning and Natural Resources)

Judging from the restored image, the Bashanosaurus primitivus was big and imposing. This tallies with the fossil found, which supports the speculation that the new species was about three meters long and about two meters high and had two columns of armored plates that ran along its back from front neck to tail and two pairs of big bone spurs at the end of its tail.

Despite an "imposing" appearance, Bashanosaurus primitivus was gentle and ate plants mostly. And the big bone spurs at the end of its tail were for self-defense.

Bashanosaurus primitivus fossil materials have been excavated from the Dinosaur Fossil Wall of the Lower Shaximiao Formation at the Dinosaur Fauna in Yunyang County. They include the shoulder blade rostral bone. Dorsal vertebra, caudal vertebra, thigh bone, shin bone, splinter bone, metatarsus, armored plates, and bone spurs at the end of the tail.

A specimen of Bashanosaurus primitivus was preserved on the Dinosaur Fossil Wall. (Photo/ Chongqing Municipal Bureau of Planning and Natural Resources)

These fossil "clues" have attracted much attention from experts at home and abroad. Senior engineer Dai Hui and research fellow, Li Ning from 208 Institute of Geological Relics Protection under Chongqing Bureau of Geology and Minerals Exploration, research librarian Susannah C. R. Maidment from the Natural History Museum of the UK, research fellow Wei Guangbiao from Chongqing Institute of Geological Survey, research librarian Peng Guangzhao from Zigong Dinosaur Museum, and other experts, have conducted a joint study on Bashanosaurus primitivus.

The dinosaur fossils. (Photo/ Chongqing Municipal Bureau of Planning and Natural Resources)

According to Dai Hui, the new species was "older" than Huayangosaurus taibaii, which was discovered in Sichuan's Zigong City, and "of the same age" as another stegosaurus species found in Argentina.

"Currently, only one in Morocco, among all the known stegosaurus is 'older' than Bashanosaurus primitivus. Judging from this, Bashanosaurus primitivus is currently the oldest stegosaurus in Asia, and also one of the oldest stegosauruses in the world." This means half of the world's four oldest stegosauruses originated in China.

According to Dai Hui, China's stegosaurus can be divided into diverse genera and species and account for about 40% of the world's total. In China, stegosaurus fossils are mainly distributed in Sichuan, Chongqing, Xinjiang, Inner Mongolia, Xizang, and other places. Though another famous stegosaurus, Chungkingosaurus Jiangbeiensis, was also found in Chongqing in history, it is the first time that a stegosaurus fossil has been discovered in Yunyang County's Dinosaur Fauna.

Moreover, the result of the joint study has been recognized by the international academic community. On March 4, Journal of Vertebrate Paleontology, a well-known SCI journal in the United States, published the research paper written by the team, New Stegosaurus from the Middle Jurassic Lower Member of the Shaximiao Formation of Chongqing, China.

Next, Chongqing will continue to focus on the protection, exploration, research, and utilization of the Dinosaur Fauna in Yunyang County to let the public experience the charm of the "museum" of dinosaur fossils as soon as possible, according to a relevant head from Chongqing Municipal Bureau of Planning and Natural Resources.