The largest dinosaur to ever walk the Earth has been found in Argentina in 2013. Today, scientists have officially named the 70-ton, 120-foot-long creature Patagotitan mayorum.

Discovered on the Argentinian desert by a shepherd, the species is believed to have belonged to extra-huge titanosaurs that lived about 100 million years earlier.

Fateful Discovery

In 2013, Aureliano Hernandez saw a fossilized bone jutting out of a rock at the farm where he worked. The farm owners got in touch with local paleontologists for the rare find; Hernandez had unfortunately already passed away when the team arrived.

It was a massive fossil all right: it took two weeks for the thigh bone to be unearthed. It was part of the titanosaurs, or the last-surviving group of sauropods or long-necked dinosaurs, and apparently the biggest of them all.

News spread quickly, and a cast of the dinosaur was finally displayed at the American Museum of Natural History last January. Renowned naturalist Sir David Attenborough also released a documentary on the awe-inducing discovery.

Now the team of Luis Carballido and Diego Pol from the Museum of Paleontology Egidio Feruglio in Argentina have officially described the species and given it the name P. mayorum, in honor of the Patagonian region where it was first detected. The second part of the name remembers the Mayo family, which owned the land and welcomes the scientists studying the fossil.

Meet The P. Mayorum

While it’s slightly smaller than formerly thought, the Patagotitan is still twice as heavy as more familiar dinosaur species, and is 10 percent larger than the Argentinosaurus, which previously held the record for size.

“Even taking into account the uncertainty of those methods [for estimating body mass], Patagotitan comes out as a 60- to 80-ton behemoth. And nothing else we know of yet comes very close,” said John Hutchinson from the Royal Veterinary College.

The dinosaur lived about 101 million years earlier, during the Cretaceous period. The team used two different methods to estimate the Paragotitan’s heaviness: an equation approximating mass based on the circumference of the femur and humerus, and a calculation of the volume based on a 3D model of the skeleton.

The researchers believed that there was probably a “major event” that led the dinosaurs to be of such ferocious size.

“As far as we know and for some reason, giant titanosaurs were present only in Patagonia. This means that in Patagonia they had the resources and weather for their subsistence,” explained Carballido to Newsweek.

Other factors, however, may have caused for this outstanding body mass to not have developed in dinosaurs in other parts of the world. Titanosaurs, for instance, likely grew to be so big to better dodge predation.

The dinosaurs were also herbivores, and flowering plants at that time became highly diverse while the climate turned warmer. Scientists could only speculate if their skeleton shape changed, their metabolism changed, or they altered their behavior.

The findings were detailed in the journal Proceedings of the Royal Society B: Biological Sciences.