Modern-day scorpions are small but creepy, and the stingers on their tails pack a painful punch. Some of their ancient relatives were also creepy, but they were big, and their tails may have packed a deadly punch.
Sea scorpions first appeared almost 470 million years ago -- one of the first big predators in the oceans. They stuck around for more than 200 million years. The first of these creepy critters lived in warm, tropical oceans and seas around the world. Later ones inhabited the oceans, marshes along the coast, freshwater lakes, and other wet environments.
Despite the name, sea scorpions weren’t true scorpions. But they’re related to modern-day scorpions, along with spiders and crabs. Most of them were only a few inches long. But a few species grew to lengths of up to six to eight feet. They had a long, tapered body; a set of claws attached to small “arms” at the front of the body for grabbing and tearing prey; and a pair of long “paddles” farther back on the body for moving through the water and digging in the mud.
Sea scorpions also had a long tail with a spike on the end. Some recent research found that the tail probably could be whipped around the body from side to side, perhaps to spear prey the creature had caught in its claws.
The largest species of sea scorpion yet discovered lived about 390 million years ago. It inhabited coastal marshes, and probably ate fish, as well as other members of its own kind -- adding to the “creepy” factor for this giant ocean predator.