Temporal range: Upper Jurassic 153 mya
In most respects, Supersaurus is similar in to Apatosaurus, but it is less robustly built. It has elongated cervical vertebrae, resulting in one of the longest known sauropod necks. It was up to 33 to 34 meters (108 to 112 ft) in length, and a weight of 35 to 40 tons.
A new and much more complete specimen of Supersaurus, nicknamed 'Jimbo', WDC DMJ-021, was found in Converse County, Wyoming in 1996. It is currently being prepared and was described in 2007. Its bones are held at the Wyoming Dinosaur Center.
- Foster J. 2007. Appendix, in Jurassic West: the dinosaurs of the Morrison Formation and their world. Indiana University Press, 327-329.
- Amphicoelias was longer.
- Lovelace, David M; Hartman, Scott A. & Wahl, William R. 2007. Morphology of a specimen of Supersaurus (Dinosauria, Sauropoda) from the Morrison Formation of Wyoming, and a re-evaluation of diplodocid phylogeny. Arquivos do Museu Nacional 65 (4): 527–544.