Supersaurus (meaning "super lizard") is a genus of diplodocid sauropod dinosaurdiscovered by Vivian Jones of Delta, Colorado, in the Upper Jurassic Morrison Formationof Colorado in 1972. The fossil remains came from the Brushy Basin Member of the formation, dating to about 153 million years ago.[1] It is among the largest dinosaursknown from good remains, possibly reaching 33 to 34 meters (108 to 112 ft) in length, and a weight of 35 to 40 tons.[2]
Most studies of diplodocid relationships have found it to contain two primary subgroups:Diplodocinae (containing those diplodocids more closely related to Diplodocus than toApatosaurus) and Apatosaurinae(diplodocids more closely related toApatosaurus than to Diplodocus). Originally, it was thought that Supersaurus was related to the long-necked diplodocid Barosaurus, and therefore a member of the subfamily Diplodocinae, though most later studies foundSupersaurus to be a close relative of the familiar Apatosaurus in the group Apatosaurinae.[2] However, some later studies cast doubt on this paradigm. One comprehensive study of diplodocoid relationships published by Whitlock in 2011 foundApatosaurus itself to lie at the base of the diplodocid family tree, and other "apatosaurines", including Supersaurus, to be progressively more closely related toDiplodocus (making them diplodocines).[4]In most respects, Supersaurus is very similar in anatomy to Apatosaurus, but it is less robustly built with especially elongated cervical vertebrae, resulting into one of the longest known sauropod necks.[2] Supersaurus is present in stratigraphic zone 5 of the Morrison, dating from the Tithonian.[3]