Ancient giant scorpion was 'an extraordinary size'

An enormous scorpion fossil has been identified as the largest known to science.

The discovery was made by experts from the University of Manchester and the Natural History Museum, who rare re-examining it 150 years after it first became part of a museum collection.

The animal, known in Latin as Praearcturus gigas, could have been as big as a dog, with pincers more than 16 centimetres long.

It would have been found on Earth around 415 million years ago, with the fossil coming from the area that is now England and Wales.

Experts think it got so big as there weren't that many predators around that could take it on.

In 1871 when the Praearcturus was first discovered and named, it was described as a giant crustacean - a large group of animals with a hard outer shell, jointed legs, and no backbone.

But the fossils were incomplete which made identifying them much more difficult.

Now researchers have been using modern analytical methods and comparisons with other fossil species, to conclude that it was actually a scorpion and its own separate species.

Experts think the reason the scorpion grew to be so large was because of the time period and conditions it lived in.

Researchers have suggested that it may have been easy for Praearcturus to dominate its environment because there were few other large predators competing for resources at this time.

Some specimens also show flap-like structures on their body similar to lobsters, which suggests they may have been able have moved between land and water.

The ongoing study of the specimen also suggests that giant arthropods like Praearcturus maybe have existed 50 million years earlier than previously thought.

Dr Richard J. Howard, is the Curator of Fossil Arthropods at the Natural History Museum, London and the lead author of the study.

He said: "Confirming that this animal is a scorpion fundamentally changes our understanding of how and when these creatures evolved to such extraordinary sizes."

Dr Russell Garwood, who is a palaeontologist at The University of Manchester, added: "What makes Praearcturus so interesting is that it became enormous at a time when life on land was otherwise very small.

"To reach such extraordinary sizes... perhaps it lived in water, where life was bigger."