The skeleton of what could be a new dinosaur species — a giant Patagonian plant-eater — has been uncovered in Argentina.

At more than 32 metres, it is among the largest ever found, scientists said Monday.

Scientists from Argentina and Brazil said the Patagonian dinosaur appears to represent a previously unknown species because of the unique structure of its neck.

They named it Futalognkosaurus dukei after the Mapuche Indian words for "giant" and "chief," and for Duke Energy Argentina, which helped fund the skeleton's excavation.

"This is one of the biggest in the world and one of the most complete of these giants that exist," said Jorge Calvo, director of the paleontology centre of National University of Comahue, Argentina, lead author of a study on the dinosaur published in the peer-reviewed Annals of the Brazilian Academy of Sciences.

Scientists said the giant herbivore walked the Earth 88 million years ago.

Since the first bones were found on the banks of Lake Barreales in the Argentine province of Neuquen in 2000, paleontologists have dug up the dinosaur's neck, back region, hips and the first vertebra of its tail.

"I'm pretty certain it's a new species," agreed Peter Mackovicky, associate curator for dinosaurs at Chicago's Field Museum, who was not involved with the discovery. "I've seen some of the remains of Futalognkosaurus and it is truly gigantic."

Patagonia also was home to the other two largest dinosaur skeletons found to date — Argentinasaurus, at around 35 metres long, and Puertasaurus reuili, between 35 and 40 metres long.

The site where Futalognkosaurus was found has been a bonanza for paleontologists, yielding more than 1,000 specimens, including 240 fossil plants, 300 teeth and the remains of several other dinosaurs.