In this undated image released by Mexico's National Anthropology and History Institute (INAH) on Monday July 22, 2013, investigators work on uncovering the tail of a dinosaur at a paleontological dig site near the town of General Cepeda in northern Mexico. Paleontologists say they have uncovered 50 vertebrae believed to be a full dinosaur tail that they say resembles the remains of a hadrosaur or crested duckbill dinosaur. Paleontologist Felisa Aguilar said they uncovered roughly half of the dinosaur which was 36 feet (12 meters) long and lived 72 million years ago. (AP Photo/INAH-Mauricio Marat)

(AP)—Mexican paleontologists say they have uncovered 50 vertebrae believed to be a full dinosaur tail in the northern desert of Coahuila state.

The National Institute of Anthropology and History says the tail is about 15 feet (5 meters) long and resembles that of a hadrosaur or crested duckbill dinosaur.

An institute Monday says it's not yet possible to confirm the species, but it would be the first full tail of that kind in Mexico.

Paleontologist Felisa Aguilar says they uncovered roughly half of the dinosaur, which was 36 feet (12 meters) long and lived about 72 million years ago.

The took 20 days in the municipality of General Cepeda in the northern state that borders Texas.

In this undated image released by Mexico's National Anthropology and History Institute (INAH) on Monday, July 22, 2013, the tail of a dinosaur is uncovered at a paleontological dig site near the town of General Cepeda in northern Mexico. Paleontologists say they have uncovered 50 vertebrae believed to be a full dinosaur tail that they say resembles the remains of a hadrosaur or crested duckbill dinosaur. Paleontologist Felisa Aguilar said they uncovered roughly half of the dinosaur which was 36 feet (12 meters) long and lived 72 million years ago. (AP Photo/INAH-Mauricio Marat)

The , working with Mexico's National Autonomous University, also found hip bones.