Barosaurus
Barosaurus ( BARR-oh-SOR-əs) is an extinct genus of giant, long-tailed, long-necked, plant-eating sauropod dinosaur closely related to the more familiar Diplodocus. Definitive remains have been found in the Morrison Formation from the Upper Jurassic Period of South Dakota, Utah and Montana, with other possible remains also found in Colorado, eastern Wyoming and Oklahoma.