This Ferocious Arachnid Is Death Wrapped in Mystery

"Oh God what is that thing!?"

You may have come across a 2004 image of an American soldier in Iraq holding two huge “camel spiders,” one of which had clamped its jaws on the other. Huge. As in, they alone were reason enough to get out of Iraq. Now, they aren’t really spiders, and through a trick of perspective (they’re just close to the camera) they look way bigger than they really are. Don’t get me wrong, the strange, hairy camel spiders do grow to six inches long—not too shabby. But size is far from the most fascinating thing about these beasts.

Camel spiders are arachnids like true spiders, but they belong to a different order, solifugae. (Depending on who you ask, camel spiders are so-called because some species have humps on their backs or because of the myth that they eat camel stomachs.) Also called wind scorpions for their incredible speed (and hey, why not confuse them for another kind of arachnid while we’re at it), these things have jaws like you wouldn’t believe—dextrous chompers that can be a third of their body length and that shred prey as big as rodents.

With these beasts comes lore. In addition to the camel stomach stuff, legend says that as camel spiders scream as they speed around the desert, that they can leap incredible distances, and that they’ll even attack humans, injecting them with a sleepy-time venom and gnawing on the victims as they slumber.

None of these things are any truer-to-life than the behaviors of camel spiders depicted in the 2011 horror movie Camel Spiders, a lazily titled film if I’ve ever heard one. But it’s true that science still knows little about the camel spider, for although they tally some 1,000 species the world over, they’re rare and almost unstudied. “For 10, maybe 15 years almost now, I’ve been doing research in the Caribbean, and I’ve spent a combined maybe four years in the field,” says arachnologist Lauren Esposito of the California Academy of Sciences. “I’ve found two. Ever.”

Why the camel spiders are so rare, Esposito can’t say. It could be that their populations are just low (they do tend to be more common in the Middle East, as opposed to the Caribbean). Being nocturnal doesn’t help humans find them either. And the fact that they burn rubber certainly doesn’t help. “If you sit under a light trap,” Esposito says, “a lot of times they’re attracted to the movement of the moths that are attracted to the light. And they’ll just come out of nowhere and grab something and run off again. They’re super fast.”

If a creature is a reasonable size compared to the camel spider, chances are the predator can overwhelm it. Larger species of camel spider go after rodents and lizards. But interestingly for a speedy predator, camel spiders “probably have really poor eyesight,” says Esposito, considering how tiny their eyes are, “and mostly sense through vibrations that they pick up in the hairs all over their body.”

As for those mouthparts: In arachnids like this they’re known as chelicerae, like the formidable fangs you find on tarantulas. But tarantulas ain’t got nothing on the camel spider’s chompers. A camel spider has a pair of chelicerae like other arachnids, but each pair is itself a pair of scissor-like, serrated blades, powered by massive muscles. Think of the creature as wielding two toothy beaks.

The camel spider’s jaws tear through everything from flesh to hard exoskeletons to the fragile human psyche.

And the camel spider’s jaws aren’t just powerful—they’re highly maneuverable. “So they can really open them up and move them almost omnidirectionally,” says Esposito. “They obviously have a lot more musculature associated with those mouthparts. So it’s almost like the mouth in Predator, where it opens up in four directions.”

While spiders and scorpions rely on venom to kill their prey, the camel spider doesn’t bother. They haven’t a drop of venom (much less a venom that can knock a human out cold, though their bites can be painful from the sheer trauma). Nor does the camel spider produce silk to trap its food. This is a minimalist hunter: nothing fancy. Just speed and teeth.

They prowl ecosystems the world over. The large desert-adapted varieties tend to have comb-like hairs on their legs that may help them shovel sand to dig burrows. “Their legs and feet become elongated,” Esposito says, “because they need to be higher up off of the substrate and have more surface ratio to stay on top of the sand, instead of sinking when they’re running.”

Regardless of geographical adaptations, what all camel spiders agree on is the freaky sex. In the sense that if you care to watch the video below, complete with inappropriate music, I’m going to explain what’s going on. That kind of freaky sex.

From the few complete courtships of camel spiders that scientists have observed, it seems that the males charge in and overpower the females. They hold on in part with sensory structures called pedipalps, which are tipped with suction cups, and “they basically bend the female in half and hold onto her and don’t let go,” Esposito says. “So they use their speed to run up quick and grab on and hold on for dear life.”

The problem is, the female may have mated with other males, who left their sperm packets in her oviduct. By gnawing on this oviduct, the male may be trying to remove his rivals’ sperm. “The way sperm works in the oviduct system is the last in is the first out,” Esposito says. “The female’s eggs are going to be fertilized by whoever the last one in was, so he’s trying to get rid of that.” He then uses his chelicerae to insert his own sperm packet.

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