an international team of scientists for the first time systematized the numerous disparate data on arthropods that lived before the great extinction events in the period from 541 to 252 million years ago. It was found that their sizes ranged from quite tiny to really huge.

the First of its kind large-scale study published in the journal Gondwana Research, and the brief version of the authors posted at the portal of The Conversation.

the Study confirmed that in the Paleozoic era in earth’s oceans inhabited by a number of arthropods, including treated and prehistoric sea Scorpions. Many fossils have been discovered in Australia, which in ancient times was part of the supercontinent Gondwana.

the First documented fossilized fragment of the exoskeleton were found in 1899 in Melbourne. But still was made only one attempt to integrate knowledge about these arthropods. In this case, the researchers re-examined fossils stored in museums. By the way, this helped to open previously unknown to science.

as a result, researchers have catalogued these ancient creatures. They took sea Scorpions six main groups. Apparently these creatures were very similar to modern Scorpions, but in their internal structure they were, rather, their cousins.

most scientists struck by the difference in the size of prehistoric creatures. Some of them were very tiny. For example, the only completely preserved specimen of a sea Scorpion belongs to specimen of Adelophthalmus waterstoni, the length of which was only 5.7 cm

But the worst was a sea Scorpion Jaekelopterus rhenaniae, the length of which, presumably, exceed 2.5 metres. This is one of the largest marine predators ever found fossilized in the rocks of Australia. Scientists say that these giants actually occupied the same place in the food chain that modern great white shark.

Despite the huge size, it was very agile swimmers. For hunting they used their large forelimbs resembling claws. To capture their prey, they are then crushed it with subphotonic spikes, which were armed with their paws.