The first Gobi sauropod Opisthocoelicaudia
The first Gobi sauropod Opisthocoelicaudia was collected from Nemegt in 1965.The specimen represents an almost complete skeleton, animatronic dinosaur except for the skull. The caudal vertebrae of Opisthocoelicaudia were hollow on the posterior. So that it why this sauropod was named Opisthocoelicaudia ( opistho- means at the back; and coelio- means literally a cavity of the body ) .The neck of Opisthocoelicaudia was relatively short in comparison with a large body.Its locomotion might be similar- to that of — current elephants. Some scholars referred it to titanosaurians other to camarasaurids.
Nemegtosaurus mongoliensis was the second sauropod described from the Nemegt Basin. The specimen of Nemegtosaurus includes a well- preserved 55cm-long skull that was lightly constructed and had large orbits. The cranial and dental characters most closely resemble those of Diciaeosaurus from East Africa, as well as those of Diplodocus from North America. The skull was found in the same formation and area as was the skeleton of Opisthocoelicaudia.Therefore some paleontologists think the both sauropod species belong to the first described genus.
More than 24 genera of dinosaurs, 15 of which were new taxa, were described based on discoveries made by the Polish- Mongolian Paleontological Expedition in Mongolian Gobi ( Osm o lska, 1997 ) .