Diplodocidae

Diplodocidae is a family of sauropod dinosaurs that includes some of the longest animals ever to walk the Earth, among them Diplodocus, Apatosaurus, Barosaurus, and the enormous Supersaurus, which may have exceeded 30 meters in length. Even by sauropod standards these were large animals, with exceptionally long necks and tapering tails, small heads set with the bony nasal openings high on the skull, and slender teeth clustered at the front of the jaws that were likely used to strip foliage from branches. Not all members were giants; the South American Leinkupal, at roughly 9 meters, was one of the smallest. The family divides into two subfamilies, the robust apatosaurines and the more slender diplodocines, the latter grouping Diplodocus with close relatives such as Barosaurus. Diplodocids probably originated in North America, where most of their fossils are found, but they ranged across most continents, occurring also in South America, Europe, and Africa. They flourished during the Late Jurassic and persisted into the Early Cretaceous in Africa and South America.