Brachiosaurus [2] (Latin Brachiosaurus - broad-shouldered lizard, from ancient Greek βραχίων [brachion] - shoulder and other Greek σαῦρος [sauros] - lizard, lizard) - genus of sauropod dinosaurs living in the territory of modern North America at the end of the Jurassic period, about 154-153 million years ago. Includes a single view.Brachiosaurus altithorax (Latin altithorax - deep-chested), described together with the genus by the American paleontologist Elmer Riggs in 1903 from fossils that were found in the Colorado River Valley in western Colorado, USA.