Giant Killer Scorpion Once Ruled Seas

[mrmoshe]

Giant killer scorpion once ruled seas

Mark Henderson, London | November 22, 2007

IT WAS one of the most fearsome sea monsters of all time, a vast sea scorpion that lurked below the surface and ambushed its prey with razor-sharp claws.

A newly discovered fossil has revealed that the predator, which lived 390 million years ago, grew to at least 2.5m, making it among the largest arthropods known to science.

Jaekelopterus rhenaniae would have lain in wait in shallow water for passing fish, seizing them with its 46cm claws in a sudden movement.

After slicing its hapless prey into smaller pieces, it would have diced it up, using saw blades on its legs, devouring it with mouth parts in its belly.

While it would normally have fed on smaller prey such as fish, it was capable of taking larger animals, and sometimes turned cannibal, consuming smaller specimens of its own kind, according to the scientists behind the discovery.

"It would certainly have made a meal of anyone going for a swim 390 million years ago," Simon Braddy, of the University of Bristol, said.

"These sea scorpions would have been truly terrifying creatures. They were like the crocodiles of the Devonian period, ambush predators that were very much top of the food chain.

"We have known for some time that the fossil record yields monster millipedes, super-sized scorpions, colossal cockroaches and jumbo dragonflies, but we never realised until now just how big some of these ancient creepy-crawlies were."

J. rhenaniae takes its name from a German scientist who first described the creature in the early 20th century after it was found in the Rhineland. Now a fossilised claw has shown it grew far larger than had been thought.

The giant claw was discovered in a quarry near Prum by Markus Poschmann, of the German Cultural Heritage Directorate in Mainz. Dr Poschmann and Dr Braddy calculated that the sea scorpion grew to at least 2.5m long, some 40cm longer than the previous largest specimen.

Arthropods have an exoskeleton and segmented bodies with appendages on each segment. The ancient sea scorpions, which were arachnids, are ancestors of modern scorpions.

During the Devonian period, from 416 to 359 million years ago, arthropods had yet to be challenged by vertebrates. The supersized sea scorpions lived alongside dragonflies with a wingspan of 75cm, and huge cockroaches.

The Times

And this from The BBC:

Man-sized sea scorpion claw found

The immense fossilised claw of a 2.5m-long (8ft) sea scorpion has been described by European researchers.

The 390-million-year-old specimen was found in a German quarry, the journal Biology Letters reports.

The creature, which has been named Jaekelopterus rhenaniae, would have paddled in a river or swamp.

The size of the beast suggests that spiders, insects, crabs and similar creatures were much larger in the past than previously thought, the team says.

The claw itself measures 46cm - indicating its owner would have been longer even than the average-sized human.

Overall, the estimated size of the animal exceeds the record for any other sea scorpion (eurypterid) find by nearly 50cm.

The eurypterids are believed to be the extinct aquatic ancestors of modern land scorpions and possibly all arachnids (the class of animals that also includes spiders).

"The biggest scorpion today is nearly 30cm so that shows you how big this creature was," said Dr Simon Braddy from the University of Bristol, UK.

It was one of Dr Braddy's co-authors, Markus Poschmann, who made the discovery in the quarry near Prum in western Germany.

"I was loosening pieces of rock with a hammer and chisel when I suddenly realised there was a dark patch of organic matter on a freshly removed slab," he recalled.

"After some cleaning I could identify this as a small part of a large claw. Although I did not know if it was more complete or not, I decided to try and get it out.

"The pieces had to be cleaned separately, dried, and then glued back together. It was then put into a white plaster jacket to stabilise it."

Super-sized meals

The species existed during a period in Earth history when oxygen levels in the atmosphere were much higher than today.

And it was those elevated levels, some palaeo-scientists believe, that may have helped drive the super-sized bodies of many of the invertebrates that existed at that time - monster millipedes, huge cockroaches, and jumbo dragonflies.

But Dr Braddy thinks the large scales may have had a lot to do with the absence early on of vertebrate predators. As they came on the scene, these animals would have eaten all the biggest prey specimens.

"The fact that you are big means you are more likely to be seen and to be taken for a tastier morsel," he told BBC News. "Evolution will not select for large size; you want to be small so you can hide away."

The scorpions are thought to have made their first scuttles on to land about 450 million years ago.

While some would have taken up a fully terrestrial existence, others like Jaekelopterus rhenaniae would have maintained an aquatic or semi-aquatic lifestyle.

How the creature compares for size with a human

[jewgaffer]

Pete that is another very interesting article. I wonder what happened to all these large creatures of old. Perhaps they were growing so big that a change in the atmosphere caused them to disintegrate.

Wouldn't it be interesting if the giant coachroaches and scorpions exploded and we were close by with a camera ay Pete

jewgaffer

[marlin1962]

Glad i didn't go swimming 390 million years ago,

that would have scared the crap out ya.

[Richie]

Pete that is another very interesting article. I wonder what happened to all these large creatures of old. Perhaps they were growing so big that a change in the atmosphere caused them to disintegrate.

Wouldn't it be interesting if the giant coachroaches and scorpions exploded and we were close by with a camera ay Pete

jewgaffer

Oxygen levels were about 30% higher then IIRC, allowing creatures like the brontoscorpio to reach immense sizes.

As the Atmosphere changed, the smaller arthropods were the more successful lifeforms and hence, in an evolutionary sense, they shrunk.

[jewgaffer]

................. in an evolutionary sense, they shrunk.

So this evolutionary sense bit may be still slowly happening and it sounds like Pete's elderly flathead may well have shrunk back to their original fry size over time.

Thanks for the info Richie, the expectation would have been a bit of fizzer on the day and there would have been no implosions of huge scorpions and two hundred pound cockroaches to look at I take it.

Cheers

jewgaffer