Omeisaurus

O-may-sore-us.
Published on

Cassidy Wood

Paleoentomologist

Cassidy Wood uncovers the tiny yet significant world of prehistoric insects. Her research on amber-preserved specimens has revealed intricate details about ancient ecosystems.

Cite Feedback Print

Name

Omeisaurus ‭(‬Omei lizard‭ ‬-‭ ‬after Omeishan Mountain‭)‬.

Phonetic

O-may-sore-us.

Named By

C.‭ ‬C.‭ ‬Young‭ ‬-‭ ‬1939.

Classification

Chordata,‭ ‬Reptilia,‭ ‬Dinosauria,‭ ‬Saurischia,‭ ‬Sauropoda,‭ ‬Mamenchisauridae.

Diet

Herbivore.

Species

O.‭ ‬junghsiensis‭

Size

Around‭ ‬10‭ ‬to just over‭ ‬15‭ ‬meters long.‭ ‬Full size depends upon the species.

Known locations

China‭ ‬-‭ ‬Sichuan Province‭ ‬-‭ ‬Dashanpu/Lower Shaximiao Formation.‭ ‬Possibly also the Upper Shaximiao though these remains are widely regarded as being indeterminate.

Time Period

Bathonian/Callovian of the Jurassic.

Fossil representation

Many individuals.

In Depth

       With its incredibly long neck Omeisaurus is both a relative and possible comtempory to the more famous Mamenchisaurus.‭ ‬However previous Upper Shaximiao Formation fossils of Omeisaurus are now considered indeterminate.‭ ‬If Omeisaurus really‭ ‬does‭ ‬only exist in Lower Shaximiao deposits,‭ ‬then it may confirm that Mamenchisaurus replaced Omeisaurus since the former is only known from the later Upper Shaximiao.‭ ‬The large number of individual Omeisaurus recovered indicates that it was a successful design that was well suited to its environment.

       Other sauropod dinosaurs active at the same time and location as Omeisaurus include Abrosaurus,‭ ‬Dashanpusaurus and the clubbed tail Shunosaurus.‭ ‬Other herbivorous dinosaurs in the same time period and general area include the stegosaur Huayangosaurus and the small bipedal ornithischian Agilisaurus.‭ ‬Numerous predatory dinosaurs also roamed the landscapes and these include Chuandongocoelurus,‭ ‬Kaijiangosaurus,‭ ‬Gasosaurus,‭ ‬Leshansaurus,‭ ‬Xuanhanosaurus and Yangchuanosaurus.‭ ‬The last one in particular is important to Omeisaurus since it could attain sizes where it would have been a serious threat to smaller Omeisaurus,‭ ‬and still dangerous enough to worry larger individuals.

Further Reading

– On a new Sauropoda, with notes on other fragmentary reptiles from Szechuan. – Bulletin of the Geological Society of China 19(3):279-315. – C.-C. Young – 1939. – New sauropods from China. – Vertebrata PalAsiatica 2(1):1-28. – C.-C. Young – 1958. – [Dinosaurs from the Jurassic of Sichuan]. Palaeontologica Sinica, New Series C, Whole Number 162(23):1-136. – Z. Dong, S. Zhou & H. Zhang – 1983. – [Omeisaurus tianfuensis—a new species of Omeisaurus from Dashanpu, Zigong, Sichuan]. – Journal of Chengdu College of Geology 1984(suppl. 2):13-32. – X. He, K. Li, K. Cai & Y. Gao – 1984. – Omeisaurus maoianus: a complete Sauropoda from Jingyan, Sichuan 1-128. – F. Tang, X.-S. Jin, X.-M. Kang & G.-J. Zhang – 2001. – [A new species of Omeisaurus from the Middle Jurassic of Zigong, Sichuan]. – Vertebrata PalAsiatica 49(2):185-194. – S. Jiang, F. Li, G.-Z. Peng & Y. Ye – 2011. – A new species of Omeisaurus (Dinosauria: Sauropoda) from the Middle Jurassic of Yunyang, Chongqing, China. – Historical Biology. – C. Tan, M. Xiao, H. Dai, X.-F. Hu, N. Li, Q.-Y. Ma, Z.-Y. Wei, H.-D. Yu, C. Xiong, G.-Z. Peng, S. Jiang, X.-X. Ren & H.-L. You – 2020.

SPECIES SPOTLIGHT