When it comes to creatures that have been sharing this planet with us for millennia, this tiny worm is probably the devil you don’t know.

That’s because the aptly named "devil worm" haunts places that are difficult, if not downright impossible, for other animal life to exist.

In fact, the first of its kind wasn’t discovered until 2008 — about a mile down a South African gold mine. The critter, which is a kind of nematode or roundworm, was immediately hailed as the deepest-living animal ever found. And that’s a distinction the devil worm is likely to keep.

After all, who else can eke out an existence amid the intense heat and squelching pressure of such depths? And what’s for dinner?

The devil worm — scientists dubbed it Halicephalobus mephisto, after the Faustian demon who presided over hell — wasn’t taking questions.

Eventually, scientists did pry loose a few of the devil worm’s secrets. For instance, to keep its svelte half-millimeter figure, it nibbles happily on bacteria. And, since it’s likely been squirming far below our feet for thousands of years, the creature has had plenty of time to evolve into its niche habitat.

But what about its strange superpower — the ability to withstand the infernal heat and impossible pressures of its own private underworld? To find a clue, scientists had to probe much deeper. In fact, researchers at American University just gave the devil worm another title: the first subterrestrial animal ever to have its genome sequenced.

The research, published this month in the journal Nature Communications, reveals a creature that’s packing a remarkable amount of Hsp70.

Known as "heat-shock" protein, Hsp70 is found in much smaller amounts in pretty much all life forms. Its job is to repair cells that are damaged from heat. And while other nematodes have Hsp70, H. mephisto boasts it in spades.

The sequencing revealed the worm’s Hsp70 genes were copies of themselves, essentially giving it duplicates and triplicates and quadri — err, you get the idea — until it could endure even the most hellish of habitats.

The worm is also packing spare copies of a gene called AIG1, which is linked to cellular survival in plants and animals.

“The Devil Worm can't run away; it's underground,” Bracht explains in a press release. “It has no choice but to adapt or die. We propose that when an animal cannot escape intense heat, it starts making additional copies of these two genes to survive.”

Those genes suggest the devil worm took a long evolutionary road to get to the point where it can make a kind of hell its home. And just maybe it can teach us a thing or two about how to live with a devil we do know: climate change.

We may look to the humble nematode, a creature with an incredible knack for rolling with environmental change. Perhaps we may even replicate its genetic hazmat suit, replete with all those insulating Hsp70 proteins.

“[Nematodes] have a reputation as some of the toughest multicellular life forms that have colonized the most inhospitable habitats,” Andreas Teske, a professor at the University of North Carolina Chapel Hill, who was not involved with the new study, tells Discover Magazine. “They have colonized every hidden corner of the planet where the most basic requirements are met — oxygen, water, bacteria as food.”

And maybe H. mephisto surfaced just in time for us to steal a page from its genetic playbook.

This may be why the 'devil worm' can live where no other animal can
Scientists complete the first-ever genome sequence of the deepest-living animal on Earth.