Dome-headed dinosaur fossil is oldest of its type ever discovered

The name of the new species, Zavacephale rinpoche, literally translates as 'head origin precious one' in English.

Experts have uncovered a fossil which shows a new species of dome-headed dinosaur - the oldest of its type ever discovered.

The Zavacephale rinpoche, is a member of a group known as pachycephalosaurs.

They are between 108 million and 115 million years old, which means this kind of dinosaur was on Earth 15 million years earlier than anyone had previously thought.

The fossil, discovered in the Gobi Desert in Mongolia, is one of the most complete dome-headed dinosaur fossils ever seen by palaeontologists.

The fossil skull was found sticking out of a rock, with more than half of its skeleton later uncovered.

It still had features such as a hand and full tail, neither of which have never been found in pachycephalosaurs before.

It had a near-complete skull and limb bones and most its backbone and hips.

The team also recovered stomach stones, which could have been used to grind its food.

The new species was discovered in the rocks of the Khuren Dukh Formation in Mongolia.

They think this particular dinosaur would likely have been one metre long (3.3 ft) and weighed around 5.85 kg (about 12.9 pounds) - but it's been described as a "teenager", so a fully grown one would have been much larger.

Although the researchers can't be sure, other pachycephalosaur species reached lengths of more than four metres and 400kg, which could suggest this one would also have grown to be much bigger.

These dinosaurs had rounded heads made of solid-bone, which they may have used to defend themselves or to help attract a mate.

The fossil also shows the skull covered in dimples, which could show it also had other unknown features on its head.

Experts think it could have been a fearsome sight, with a mouth full of sharp teeth and giant eye sockets.

The skull of Zavacephale suggests that the domes of pachycephalosaurs grow more quickly than the rest of their body

Lindsay Zanno, a palaeontologist at North Carolina State University, who is a co-author of the study, said: "Pachycephalosaurs are iconic dinosaurs, but they're also rare and mysterious.

"Before Zavacephale, our record of pachycephalosaurs was almost exclusively limited to their indestructible domes," Lindsay explains.

But she added: "The well-preserved skeleton of Zavacephale is helping us fill in the blanks with its reduced forelimbs, tiny hands and stomach stones for grinding food."