Researchers have uncovered the fossils of one of the largest dinosaurs to ever walk on the Earth – remains which they believe could belong to a previously undiscovered species.

Paleontologists digging near the city of Morella in eastern Spain discovered the remains of a gigantic dinosaur which would have measured a staggering 20-meters (65 ft) from head to tail.

The team unearthed over 80 bones belonging to the same dinosaur, Spanish newspaper El Pais reports. Included in this haul were two femurs, a humerus, other parts of limbs and vertebrae from the tail of a sauropod dinosaur from the Early Cretaceous period.

Sauropods were giant plant-eaters with a distinctive long neck. The largest animal to ever walk the Earth, the brachiosaurus, was a type of Sauropod.

From studying the prehistoric remains, researchers were able to determine that the giant plant eater survived on the tender shoots of trees and also ate stones to aid digestion.

One of the directors of the excavation, Jose Miguel Gasulla, revealed that one of the femurs measures 1.60 meters (5ft 3ins). From this measurement, the team could work out that the total length of the giant beast was more than a 10-storey building.

Gasulla says the remains are important given their excellent condition and, crucially, because they could be those of a previously unknown species of sauropod.

Further investigative work needs to be carried out to fully confirm this hypothesis but, if it is confirmed, it would be the second previously unknown species of dinosaur found in Morella.

In 2015, the partial remains of 20ft-long herbivore were discovered there. The dinosaur, which also dated back to about 125 million years ago, was given the name ‘Morelladon beltrani’.

Despite its enormous size, the new dinosaur bones are still not even the largest to have ever been found in the region – that honor goes to a femur measuring 1.80 meters (5ft 11ins).

The research was funded by the city of Morella and the remains will be taken to a museum in the town after they have been studied by paleontologists.

Gasulla said that the discovery confirms that the region is a key location in palaeontological investigation: “It supposes a definitive accolade to the palaeontological heritage that we have, it does nothing more than confirm it.”