Alamosaurus

Alamosaurus was a titanosaur, a gigantic plant-eating dinosaur from the Upper Cretaceous period, about 73 million to 65 million years ago. 
"Alamosaurus" was a long-necked, whip-tailed dinosaur. It was about 69 feet (21 m) long and weighed perhaps 33 tons (30000 kg). Fossils have been found in New Mexico, Texas, and Utah. Fossils include fragmentary skeletons (and no skulls).
Skeletal elements of "Alamosaurus" are among the most common Late Cretaceous dinosaur fossils found in the American Southwest and are now used to define the fauna of that time and place. There was a climate change in this area, it became drier, and this caused changes in the fauna. Thomas M. Lehman describes it as "the abrupt reemergence of a fauna with a superficially 'Jurassic' aspect". These faunas are dominated by "Alamosaurus" and feature abundant "Quetzalcoatlus" in Texas. The "Alamosaurus" "Quetzalcoatlus" association probably represent semi-arid inland plains.p201