The giant millipede was a fluke discovery in northern England:
The fossilized remains of the creature, named Arthropleura, dated from the Carboniferous Period about 326 million years ago. That’s over 100 million years before the rise of the dinosaurs.
When alive, the creature was estimated to have been 55 centimeters (22 inches) wide and up to 2.63 meters (8.6 feet) in length, weighing 50 kilograms (110 pounds). That would make it the largest-known invertebrate of all time — larger than ancient sea scorpions that previously held this title, the statement said. Invertebrates are animals with no backbone.
Katie Hunt, “Fossil of a giant millipede reveals ‘the biggest bug that ever lived’” at CNN
It took four paleontologists to carry the fossil up the cliff.
Imaginative but gives the basic idea:
A fluke discovery. And we’ve only begun to scratch the surface of the remarkable stuff that’s out there.