Giant millipedes as big as cars once roamed the earth

By Mark Waghorn via SWNS

A giant millipede as big as a car once roamed the earth.

The armored creepy-crawly reached nine feet long - and weighed up to 112 pounds.

It was the largest invertebrate in history - bigger than ancient sea scorpions that were the previous record holders.

Named Arthropleura, the 'king of the forest' lived 326 million years ago - long before the Age of Dinosaurs.

Its skeleton was found on a beach 40 miles north of Newcastle in England.

The discovery was made purely by chance after a large block of sandstone fell from a cliff at Howick Bay.

Lead author Dr. Neil Davies, of Cambridge University, said: "It was a complete fluke.

"The way the boulder had fallen, it had cracked open and perfectly exposed the fossil, which one of our former Ph.D. students happened to spot when walking by.

"It was an incredibly exciting find - but the fossil is so large it took four of us to carry it up the cliff face."

The creature's perfectly preserved grave dates back to the Carboniferous - a period that saw complex and varied plant life flourish.

It saw the evolution and spread of trees - stabilizing river banks and allowing primitive arthropods like Arthropleura to thrive.

The specimen is made up of multiple articulated exoskeleton segments - broadly similar in form to modern millipedes.

It's only the third such fossil ever found - as well as being the oldest and mightiest.

The fossil measured 2ft 6 inches but enabled a full reconstruction of the original animal.

Dr. Davies said: "It's estimated to have measured around 2.7 meters long (9ft) and weighed around 50 kilograms (8st)."

Unlike the cool and wet weather associated with the region today, Northumberland had a more tropical climate during the Carboniferous.

Great Britain lay near the Equator and invertebrates and early amphibians lived off the scattered vegetation around a series of creeks and rivers.

Arthropleura - described in the Journal of the Geological Society - was unearthed in a fossilized river channel.

It was likely a molted segment of shell that filled with sand - entombing it in perfect condition for hundreds of millions of years.

The fossil was extracted in May 2018 with permission from Natural England and the landowners, the Howick Estate.

It was brought back to Cambridge so it could be examined in detail. Analysis revealed new information about Arthropleura's habitat and evolution.

The animal can be seen to have only existed in places that were once located at the Equator.

Previous reconstructions have suggested it lived in coal swamps. But the new specimen showed Arthropleura preferred open woodland near the coast.

There are only two other known Arthropleura fossils - both from Germany and much smaller. There is still much to learn, said Dr. Davies.

He explained: "Finding these giant millipede fossils is rare. Once they died, their bodies tend to disarticulate.

"So it’s likely the fossil is a molted carapace the animal shed as it grew.

"We have not yet found a fossilized head - so it's difficult to know everything about them."

Arthropleura's dimensions have previously been attributed to a peak in atmospheric oxygen during the late Carboniferous and Permian periods.

But because the new fossil comes from rocks deposited before this peak, it shows that oxygen cannot be the only explanation.

To get such a great size, Arthropleura must have had a high-nutrient diet.

Dr Davies said: "While we can’t know for sure what they ate, there were plenty of nutritious nuts and seeds available in the leaf litter at the time.

"They may even have been predators that fed off other invertebrates and even small vertebrates such as amphibians."

Arthropleura animals crawled around Earth's equatorial region for around 45 million years, before going extinct during the Permian period.

The cause of their extinction is uncertain but could be due to global warming that made the climate too dry for them to survive, or to the rise of reptiles, who out-competed them for food and soon dominated the same habitats.

The fossil will go on public display at Cambridge's Sedgwick Museum in the New Year.

Millipedes are cylindrical or slightly flattened invertebrates that have inhabited the planet for more than 400 million years.

They are among the earliest animals to breathe air - and are closely related to lobsters, shrimp and crayfish.

The word 'millipede' translates to 'a thousand feet' - even though most species tend to have a few hundred legs or less.

Only one millipede species has 1,000 legs - Eumillipes Persephone, reported in 2021 and uncovered in a Western Australian mine.

Millipede bodies are split into a number of segments, and each segment has two sets of legs that attach to the body's underside.

There are 7,000 species of millipede in the world, and 1,400 of these occur in the US and Canada.

The smaller ones are less than an inch in length, but the common spirobolid millipede can grow to more than five inches.