Franz Anthony
New research reveals that the largest scorpion ever is the Praearcturus gigaswhich measured more than a meter in length
Fossil fragments found in the UK have been identified as the remains of the largest scorpions ever. The so-called Praearcturus gigas was one of the first large predators on Earth.
A England and Wales they were the habitat, millions of years ago, of the largest scorpion in the world. Although fossils of Praearcturus gigas have been known for more than a century, their identity has been the subject of controversy.
With tongs 16 centimeters long and a body length estimated at more than one meter, this scorpion will have dominated the alluvial plains 415 million years ago, details a new report, published this Tuesday in Palaeontology.
According to , life on land was still relatively new during the early Devonian period, meaning that few other animals would have reached such large sizes.
When Praearcturus was first named in 1871, it was thought to be a giant crustaceanrather than another arthropod. In the 1980s, researchers began to suspect that Praearcturus might actually be a scorpion. However, it was difficult to prove.
Only a few fragments of the animal’s body survived as fossils, and they did not include the scorpion’s characteristic tail. This changed when an ancient scorpion named Eramoscorpius it was described in Canada in 2025.
“Praearcturus is similar in age to Eramoscorpius and also has one of these structures. Therefore, this demonstrates beyond doubt that Praearcturus must be a scorpion,” said the study’s first author, Richard Howard.
The identity of this scorpion is important because it provides new details about one of the most important moments in Earth’s history. Fossil sites of Devoniano show that small plants just a few centimeters tall were spreading across the land and beginning to develop adaptations that would later lead to the first forests.
However, the lives of the animals that made the transition to land are less known. According to the researcher, although there was less competition during land hunts, species like Praearcturus needed to sustain themselves through larger aquatic prey.
“Without ecosystems that support Praearcturus on land, these animals likely spent part of their lives in hunt in the water. Some of the fossils found in Wales show that they had fin-like structures, which are similar to those found in lobsters and crabs,” Howard concluded.
