Scientists have announced the discovery of a new species of gigantic dinosaur believed to have weighed more than seven T-Rexes.

The massive plant eater, known as the Dreadnoughtus schrani, has been unearthed in an Argentinian desert.

Believed to have died between 83 and 66 million years ago, the Dreadnoughtus weighed more than 59 tonnes and was 26 metres long from head to tail.

The team that discovered the dinosaur’s remains in southern Patagonia was lead by American palaeontologist Kenneth J. Lacovara.

“What we can say with certainty is this is the biggest land animal that we can actually put a number on,” Dr. Lacovara told The Age.

“We’ve got 16 tons of bone in my lab right now.”

The name of the animal means “fear nothing”, an apt descriptor for a creature that had “the body of a house, the weight of a herd of elephants and a weaponised tail,” Dr Lacovara said.