Alamosaurus

About 26 metres (85 ft) long, 5 metres (16 ft) tall at the shoulder, and weighed up to 30 to 35 tonnes (33 to 39 short tons). Some specimens suggest it could have been even larger, possibly the largest dinosaur found in North America.31

It was an herbivore, meaning it ate plants. It had a long neck to reach high or low vegetation.13

It lived during the Late Cretaceous period, about 70 to 66 million years ago, right up to the end of the Age of Dinosaurs.13

Fossils have been found in the southwestern United States, including New Mexico, Texas, Utah, and Wyoming. The first fossils came from the Ojo Alamo Formation in New Mexico.34

Yes, it is a dinosaur. It belongs to the group called sauropods, which were large, long-necked, plant-eating dinosaurs.13

Yes, much bigger. Alamosaurus was about 26 metres (85 ft) long and weighed up to 35 tonnes, while T. rex was about 12 metres (40 ft) long and weighed around 8 tonnes.3

Yes, its body was partly covered with bony armor called osteoderms, which acted like a protective shield.3

Scientists think it may have migrated from South America or Asia, because no other sauropods lived in North America for about 30 million years before Alamosaurus appeared.34