Fossil Study Identifies Giant Scorpion Species From Early Devonian Wales

A fossil study has identified a metre-long scorpion species with pincers exceeding 16 centimetres that lived on the floodplains of what is now England and Wales. The species, named Praearcturus gigas, is described as the largest scorpion of its kind on record.

The animal existed during the Early Devonian period, roughly 415 million years ago, when small plants and fungi had begun to appear on land but trees and complex forests had not yet evolved. Researchers examined a specimen from the St Maughan’s sandstone formation in Wales that had been stored at the Natural History Museum for more than 150 years.

For over a century the fragmentary fossils were thought to belong to a giant crustacean similar to a woodlouse because key features such as a tail were missing. Recent discoveries of better-preserved specimens and advanced imaging techniques allowed researchers to determine the fossils represent a distinct scorpion species.

“Confirming that this animal is a scorpion fundamentally changes our understanding of how and when these creatures evolved to such extraordinary sizes,” said the lead author of the study published in the journal Palaeontology.

The scorpion lived when most terrestrial life remained small. Researchers suggest it may have spent part of its life in water, aided by flap-like abdominal structures similar to those in modern crustaceans such as lobsters. “The boundary between land and sea was much less defined at this time,” said a study co-author from the Natural History Museum.

Specimens collected more than a century ago continue to yield new information when examined with current analytical methods.