A group of Mexican paleontologists discovered a full dinosaur tail in the northern desert of Coahuila state, which lies on the border with the United States, across the Rio Grande River from Texas.

Officials from the National Institute of Anthropology and History confirmed that the newly discovered tail with about 50 vertebrae, measures an estimated 15 feet and resembled that of a hadrosaur, or crested duckbill dinosaur. Researchers said these dinosaurs once roamed the regions now known as the North American continent, Europe and Asia.

Hadrosaurs first appeared during the Cretaceous period near the end of the Age of Dinosaurs. Based on their teeth shape and size, which were leaf-shaped and small, paleontologists believe they were plant eaters. Their size ranged from 10 feet to 40 feet and they weighed up to 3.5 tons. The dinosaurs used their large muscular hind legs for walking, they used all four legs very rarely.

According to a Reuters report, Francisco Aguilar, INAH's director in the border state of Coahuila, said that the tail was unusually well preserved and the first time a full tail of its kind has been discovered in Mexico, though it is still too early to confirm the species.

NY Times notes that the tail belonged to a dinosaur that was approximately 36 feet (12 meters) long and lived about 72 million years ago.

The excavation in the municipality of General Cepeda took nearly three weeks.