Arthropleura, An Extinct Giant Millipede

Arthropleura is an extinct giant millipede that lived around 315 to 299 million years ago during the late Carboniferous period (before the dinosaurs).  Its name translates to "Jointed rib" which refers to its segmented body. Arthropleura's flattened body is composed of approximately 30 jointed segments each of which is covered by two side plates and one center plate. The ratio of legs to the body segments is approximately 8:6, similar to some modern day millipedes.

Arthropleura grew up to at least 2.6 meters or 8.5 feet long and is the largest land dwelling arthropod (invertebrate) to ever walk the earth.

Arthropluera lived close to the equator in what is now northeastern North America and Scotland.

During the Carboniferous period (359.2 to 299 million years ago) , the growth of vast lowland swamp forests removed huge amounts of carbon dioxide from the atmosphere leading to a greater abundance of oxygen and allowing creepy crawlies to grow immense in size. The atmospheric oxygen levels peaked around 35 percent, compared with 21 percent today.

Swamp forests dominated most of the landscape during this time.

Other bugs also lived in these forests alongside Arthropleura such as Meganeura, a dragonfly the size of a hawk, and large scorpions like Pulmonoscorpius.

Amphibians in the Carboniferous also grew in size and diversity. There were predatory amphibians that resembled modern day crocodiles and some amphibians even developed scaly skin to solve the problem of them drying out from being out of the water too long.

Despite its large size, Arthropleura is a herbivore. Scientists have found spores from plant like ferns in fossil fragments.

Arthropleura's best defense was its plated armor but when threatened, Arthropleura could rear itself up, tall enough to look a human right in the eye.

Arthropleura went extinct during the Permian Mass extinction. Earth started losing oxygen, the very gas that created these large bugs was disappearing. Earth also began to get hotter and drier due to volcanic activity. The swamp forests that once supported life became deserts. The Permian Extinction was Earth's most severe extinction and wiped out 90% of all life on Earth. This was the only mass extinction that affected insects and result of this extinction gave way to the rise of the dinosaurs. Reptiles that were once outsized could now evolve into many different forms.

Arthropleura was first discovered in 1853 when tracks of it were found in fossilized Carboniferous mud in Scotland.

Unfortunately, no complete fossil of a large individual Arthropleura has been found. This probably due to fact that after the animal's death its segmented body falls apart thus leading to only individual segmented plates being preserved as fossils.

This picture shows a life-size model of an Arthropleura.

Even though Arthropleura is the largest land dwelling Arthropod, the largest Arthropod ever is actually Jaekelopterus, an extinct sea scorpion.

Check out /r/Creatures_of_earth for more stuff like this