A labrador-sized dinosaur was wrongly categorised when it was found and is actually a new species, scientists have discovered.

Its new name is Enigmacursor - meaning puzzling runner - and it lived about 150 million years ago, running around the feet of famous giants like the Stegosaurus.

It was originally classified as a Nanosaurus but scientists now conclude it is a different animal.

Enigmacursor is tiny by comparison. At 64 cm tall and 180 cm long it is about the height of a labrador, but with much bigger feet and a tail that was “probably longer than the rest of the dinosaur,” says Professor Susannah Maidment.