Period of life:
218-211 million years ago
Argentina (South America)
Riojasaurus was the closest relative of Melanorosaurus, which lived from the late Triassic to the early Jurassic. Riojasaurus had a heavy body, massive legs, a long neck and tail. The bones of its legs were dense and massive. The teeth of Riojasaurus were leaf-shaped and serrated. On the upper jaw there were 5 teeth in front and another 24 behind them in a row all the way to the eyes.
In 2010, scientists estimated its length at almost 7 meters and weight at 800 kilograms, as its vertebrae were lightened by empty cavities. However, research at the University of Bristol has revealed a number of unique traits of this herbivorous giant, such as, for example, long bony vertebrae. This greatly distinguishes the ancient herd animal from other dinosaurs discovered in the Los Colorados Formation in Argentina. Riojasaurus is also the only known Riohasaurid to have lived in South America.