(Omei lizard - after Omeishan Mountain).
Named By: C. C. Young - 1939.
Classification: Chordata, Reptilia, Dinosauria, Saurischia, Sauropoda, Mamenchisauridae.
Species: O. junghsiensis (type), O. changshouensis, O. fuxiensis, O. jiaoi, O. luoquanensis, O. maoianus, O. tianfuensis.
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.
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
indeterminate. If Omeisaurus really does only
exist in Lower
Shaximiao deposits, then it may confirm that Mamenchisaurus
Omeisaurus since the former is only known from the
Shaximiao. The large number of individual Omeisaurus
indicates that it was a successful design that was well suited to its
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.