B. lentus (type)
B. africanus

Barosaurus ("heavy lizard") was a giant, long-tailed, long-necked, plant-eating dinosaur closely related to the more familiar Diplodocus.

Characteristics

Barosaurus was a large but fairly typical diplodocid that lived during the Late Jurassic period, around 150 million years ago. In fact, in many respects Barosaurus was very similar to Diplodocus itself, but with slight differences: much longer backbones (vertebrae) a shorter tail, and a much longer neck. Although its neck bones (cervical vertebrae) numbered 15 in total, just as in Diplodocus, some of them were more than 1 m (39 in) long. The scoops and hollows in their structure mean that the neck as a whole was probably light. Probably more than four-fifths of this plant-eater's total length of perhaps 27 m (90 ft) was neck and tail. Presumably it had a small head, although no specimen of its skull has been recovered.

The American Museum of Natural History in New York City shows the skeleton of a "mother" Barosaurus rearing on her hind legs to an enormous height to protect her offspring from a small Allosaurus. Her head would be level with the fifth story of a building.

Discovery

Barosaurus is one of the many sauropods discovered in North America during the "Wild West Dinosaur Hunts" (the "Bone Wars") of the late 19th century. Othniel Charles Marsh named it in 1890. The name is also applied to specimens once classified in the genus Tornieria.

Starting in 1922, three fairly complete Barosaurus skeletons were dug out of Carnegie Quarry, Utah, by a team lead by Earl Douglas of the Carnegie Museum of Natural History, in Pittsburgh, Pennsylvania. Earlier, he had excavated Apatosaurus from the same site, and had been involved in setting up the Dinosaur National Monument there in 1915.

More Barosaurus remains were uncovered in South Dakota and, more recently, pieces of skull, limbs and other fragments of a specimen from Tanzania in East Africa have also been assigned to Barosaurus.

External Links

• Barosaurus fact sheet, from Enchanted Learning.

• Barosaurus "heavy lizard", by T. Mike Keesey at The Dinosauricon.