Millipedes are sometimes referred to as “1,000-legged worms” because of their many legs. The title “millipede” is a misnomer because the leggiest of the more than 7,000 species we know only has roughly 750 legs—until today, that is—despite the fact that no other organism has as many legs. The first real millipede with more than 1,000 legs has been discovered by biologists in Australia. If we’re being precise, that’s 1,306 teeny, tiny legs.
In Greek mythology Persephone, the goddess of the underworld, is referred to as Eumillipes persephone, a new species that was discovered crawling through the soil far down.
Researchers that study millipedes, known as diplopodologists, have long sought to uncover one that truly fits the term. For more than a century, the previous record holder with a leg count of 750 had not been beaten.
But then in the summer of 2020, while most of us were confined to our homes under COVID lockdown, a Western Australian biologist discovered E. persephone in a borehole drilled at a mineral-mining location in Western Australia. The newly discovered species is the deepest-dwelling millipede, surviving at a depth of over 60 meters (200 feet).
As a millipede expert, Paul Marek of Virginia Tech is one of the best in the world, having found more than 60 species in his career. Buzatto sent Marek specimens. Electron microscopy and DNA sequencing were used in Marek’s lab to conduct a thorough investigation. For the record, females had 1,306 limbs, but males only had 998, which was just shy of the threshold of 1,000. The counting was done by hand, one tiny appendage at a time, with no assistance from computers.
As thin as a USB cable, this brown crawler is over 10 centimeters (4 inches) in length and weighs about the same as one. The fact that it lacks eyes is rare for an animal of this kind, but considering how well it has adapted to life below, it shouldn’t be too shocking. Furthermore, E. persephone’s environment is to blame for its lack of pigmentation, a trait that is quite rare among millipede species.
Illacma plenipes, an invertebrate native to California and the previous record holder with 750 legs, is the only other millipede that looks identical. Convergent evolution—the process by which distantly related species independently evolve identical qualities to meet similar needs–is what entomologists believe the two creatures are.
Marek’s previous study with similar organisms leads him to conclude that the millipede’s super-elongation and shorter legs resulted from all those years of evolution underground. For E. persephone’s survival in the underworld, having more, shorter legs gives extra propelling force because nutrients are in short supply.
Furthermore, it’s worth noting how fortunate the researchers were to uncover E. persephone.
“I don’t think we would have known about this had it not been for the mineral exploration that’s occurring,” Dennis Black, the millipede expert from LaTrobe and a co-author on the paper, told CNet.
In the meantime, the researchers are wondering if a millipede with even more legs can be discovered. E. persephone is most likely to be found at the Western Australian site where it has made its home. Only deep-dwelling millipedes would be able to fend off predators with their long legs. But because of this, entomologists have a difficult time seeing them.
