Anatomy: Supersaurus was a long-necked, whip-tailed giant that had a tiny brain. Supersaurus held its neck more or less horizontally (parallel to the ground). This dinosaur was about 138 feet (42 m) long and 54 feet (16.5 m) tall, with a 39 foot (12 m) long neck. Supersaurus may have weighed about 55 tons. The nostrils were at the top of the head. It had peg-like teeth, but only towards the front of the jaws - there were no teeth in the back of the jaws. Its front legs were shorter than its back legs, and all the legs had elephant-like, five-toed feet. One toe on each foot had a thumb claw, probably for protection.

When Supersaurus Lived: Supersaurus lived during the Jurassic period, about 155-145 million years ago. There were many huge dinosaurs during this period.

Diet: Supersaurus was an herbivore (a plant-eater). It ate plants using its peg-like teeth. Its main food was probably conifers, which were the dominant plants when the large sauropods lived. Secondary food sources may have included gingkos, seed ferns, cycads, bennettitaleans, ferns, club mosses, and horsetails. It must have eaten a tremendous amount of plant material each day to sustain itself.

Fossils and Name: The first Supersaurus fossil was found in western Colorado, USA, by paleontologist James A. Jensen in 1972, and was named in 1985. It is only known from an incomplete fossil which includes two shoulder blades 8 feet (2.4 m) long, ribs 10 feet (3 m) long, neck vertebrae 4.5 feet (1.4 m) long, and a pelvis 6 feet (1.8 m ) wide.

Supersaurus means "super lizard;" it was given this name because it is so big.