Omeisaurus (Greek for "Omei Mountain lizard"); pronounced OH-may-SORE-us
Woodlands of eastern Asia
Late Jurassic (165-160 million years ago)
Size and Weight:
About 50 feet long and 5-10 tons
Large size; extremely long neck
Pound for pound, Omeisaurus was probably the most common sauropod of late Jurassic China, at least to judge by its numerous fossil remains. Various species of this unusually long-necked plant-eater have been unearthed over the last few decades, the smallest measuring only about 30 feet long from head to tail and the largest having a neck of about the same size. This dinosaur's closest relative appears to have been the even longer-necked sauropod Mamenchisaurus, which had a whopping 19 neck vertebrae compared to the 17 of Omeisaurus.