Meet Eumillipes persephone: a true millipede with 1,306 legs

Eumillipes persephone was discovered by accident, while a team of researchers were conducting “a subterranean environmental impact assessment.” Science News reports that eight specimens were caught “by dropping cups baited with leaf litter into drill holes used for mineral prospecting that were up to 60 metres deep. Eventually, the creatures were sent to entomologist Paul Marek at Virginia Tech in Blacksburg for a closer look.”

Speaking to 'All Things Considered' on NPR, Marek posits that the name millipede is “actually an exaggeration. It's a misnomer. There are no millipedes until now that had more than 750 legs.”

Millipede, for etymologists – that is, for word origin enthusiasts – means a thousand feet. But up until now, no millipede had lived up to its name. The one with the most feet was Illacme plenipes of California, with a maximum of 750 legs, whereas Eumillipedes persephone, that is, ‘true millipede persephone,’ has 1306. E. persephone is named after the Greek goddess of the underworld.

Illacme plenipes, too, is a burrower, like Eumillipedes persephone, according to the UK’s National History Museum, but not as deep: 

“The previous record-holder for most legs was collected 11.5 metres deep in the soil,” says  Dr Greg Edgecombe, who specialises in researching the evolution of arthropods and was not involved in the recent discovery. The new finds in Western Australia were caught in traps between 15 and 60 metres underground.

Marek et al write in Scientific Reports that “E. persephone possesses troglomorphic features; it lacks eyes and pigmentation, and it has a greatly elongated body—features that stand in stark contrast to its closest surface-dwelling relatives in Australia and all other members of its order.”

Marek's colleague Juanita Rodriguez, with the Australian National Insect Collection, tells NPR that “The width of the millipede is a little less than one millimetre, and then the length is a little less than one centimetre. So it's teeny tiny.”

Dr Rodriguez tells the Guardian that the new species had likely evolved its length for ease of movement underground.

“The more length you have, the more strength to propel forward,” she says. The millipede’s more than 300 body segments would also give it greater force for movement in rocky areas such as small crevices, she adds.

Dr Bruno Buzatto, a biologist at Bennelongia Environmental Consultants, describes the find as “incredibly lucky”.

“These animals were so unique,” Buzatto tells the Guardian. “As soon as I realised how long they were … I realised they had to be something completely different.”

Not much is known about the new millipedes. “It’s a good bet that they eat fungi,” Buzatto says.

There are more than 2,000 known species of millipede in Australia, Rodriguez says, adding that the true number of species may be as high as 4,000.

Rodriguez and her colleagues at CSIRO [Australia's national science agency] are studying the insects for the chemicals they discharge. “We’re testing them to see if they have potential for being antimicrobials against the pathogens that have a lot of antimicrobial resistance.” 

“Few people realise … the large proportion of Australian biodiversity that is still undescribed, and therefore also the importance of taxonomists,” Buzatto comments. “We essentially are driving species extinct, probably quicker than we describe them.”

THUMBNAIL PHOTO: The leggiest animal on the planet, Eumillipes persephone, from Australia. (A) female with 330 segments and 1,306 legs (paratype specimen, T147124).

HEADLINE PHOTO: (B) ventral view of legs (male holotype, T147101). (C) dorsal view of head and ventral view of gonopods (male holotype, T147101). Scale bars, 0.5 mm.