Giant sea scorpion fossil discovered
YOU WOULDN’T WANT to bump into this guy when you were out for a leisurely swim! Palaeontologists at Yale University have discovered fossils belonging to a giant predatory sea scorpion.
Dubbed Pentecopterus decorahensis, thanks to its resemblance in shape to the ancient Greek warship known as a penteconter, the animal could grow to almost two metres in length and had a heavily armoured head and large, grasping limbs for trapping prey.
The creature lived around 467 million years ago, making it the oldest eurypterid – a group of aquatic arthropods that were the ancestors of modern spiders, lobsters and ticks – discovered to date. Researchers say that it is likely to have lived in shallow, brackish water with a low salt content that would have been inhospitable to more typical marine animals.
“This discovery shows that eurypterids evolved some 10 million years earlier than we thought, and the relationship of the new animal to other eurypterids shows that they must have been very diverse during this early time of their evolution, even though they are very rare in the fossil record,” said James Lamsdell, a postdoctoral geologist who was lead author of the study, which was published in the journal BMC Evolutionary Biology.
The fossils were unearthed in a flooded meteorite crater near to the Upper Iowa River in northeastern Iowa, USA. Both adult and juvenile Pentecopterus decorahensis specimens were found, giving the researchers a wealth of information about the animal’s physiology and development. The lack of oxygen in the crater has also meant that the fossils are incredibly well preserved.