A fearsome giant sea scorpion fossil discovered in Germany belonged to the biggest bug ever known.
The size of a large crocodile, the 390-million-year-old sea scorpion was the top predator of its day, slicing up fish and cannibalizing its own kind in coastal swamp waters, fossil experts say.
Jaekelopterus rhenaniae measured some 8.2 feet long, scientists estimate, based on the length of its 18-inch, spiked claw.
The archeology discovery shows that arthropods—animals such as insects, spiders, and crabs, which have hard external skeletons, jointed limbs, and segmented bodies—once grew much larger than previously thought, said paleobiologist Simon Braddy of the University of Bristol in the United Kingdom.
The newfound fossil creature is estimated to be at least one and a half feet longer than any previously known prehistoric sea scorpion, a group called eurypterids.
Braddy and co-author Markus Poschmann of the Mainz Museum in Germany report the find in the latest issue of the journal Biology Letters.
Poschmann uncovered the fossilized claw in a quarry near Prum in Germany. Rock layers encasing it suggests the creature lived in a brackish coastal swamp or river delta, the researchers said.
Smaller sea scorpions are known to have crawled ashore to mate or shed their outer skins. However, there’s no way this monster bug would have been able to do that because it was just too big.
Some researchers believe that some primitive jawless fish evolved protective bony shields due to predatory pressure from sea scorpions.
The animal’s claws were armed with long sharp teeth that would have grasped even a slippery fish. Held at the ready on two long, folding arms, those claws would have been used to ambush prey.