Supersaurus

Supersaurus is a genus of diplodocid sauropod dinosaur first discovered by Vivian Jones of Delta, Colorado, in late Jurassic period rocks of the middle Morrison Formation of Colorado in 1972, and later in Portugal under the name S. lourinhanensis. The fossil remains came from the Brushy Basin Member of the formation, dating to about 153 million years ago.

It is among the largest dinosaurs known from good remains, possibly reaching 33 to 34 meters in length, and a weight of 35 to 40 tons.

In most respects, Supersaurus is very similar in anatomy to Apatosaurus, but it is less robustly built with especially elongated cervical vertebrae, resulting in one of the longest known sauropod necks.