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Alamosaurus sanjuanensis

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"Alamo Mountains Lizard"

Describer Gilmore, 1922
Also Known As --
Type of Species sanjuanensis
Order Saurischia
SubOrder Sauropoda
InfraOrder --
Micro-Order --
Family Titanosauridae
Size 69 feet (21 meters) long
Period Late Cretaceous, 73-65 million years ago
Fossilsite New Mexico, Texas, Utah, USA
Diet Herbivore

Alamosaurus sanjuanensisAlamosaurus sanjuanensis lived during the Late Cretaceous Period about 73-65 million years ago in what is now North America. This large sauropod was perhaps the last giant herbivore to live in the North American West. Giant sauropods dominated the American West at the end of the Jurassic Period, 145 million years ago. They seem to be absent from North America for at least 25 million years ago.

Alamosaurus's body was as large as that of Apatosaurus, its tail, however, seems to have been a few yards shorter than the famous Apatosaurus whip like tail. It weighed about 30 tons, as much as 6 elephants. Alamosaurus was descended from the South American dinosaurs that moved northward once the landmasses of the Americas were reunited near the end of the dinosaurs about 65 million years ago. Some relatives had armor on their bodies, but it is not known if Alamosaurus shared that trait.