10 of the World's Strangest Spiders

Wirepec // iStock
Wirepec // iStock

All spiders have eight legs, but that’s where most of their similarities end. Scientists frequently discover new species with unexpected talents—be it a flair for cartwheels or the ability to turn itself into a disco ball. Researchers have also found plenty of specimens that are just plain weird-looking. Here’s a list of 10 fascinatingly freaky arachnids.

1. CEBRENNUS RECHENBERGI // THE FLIC-FLAC SPIDER

A native of the Erg Chebbi desert in southeastern Morocco, Cebrennus rechenbergi—also known as the flic-flac spider—has the remarkable ability to cartwheel its way out of danger. When threatened by a predator, it will leap off the ground and do a series of high-energy somersaults to make a quick exit. An alarmed flic-flac spider can tumble forward at a rate of 6.6 feet per second—twice as fast as its maximum walking speed. If pressed, it can even cartwheel uphill. Such talents did not go unappreciated by this spider’s discoverer, bionics expert Ingo Rechenberg, who has built a somersaulting robot based on the flic-flac’s locomotion.

2. BAGHEERA KIPLINGI // A JUMPING SPIDER

Bagheera kiplingi spider
Maximilian Paradiz // Wikimeda Commons // CC BY 2.0

Those who have read Rudyard Kipling’s The Jungle Book may have already figured out that this species was named after the panther who helps raise Mowgli. But its pop culture connection is not Bagheera kiplingi’s only claim to fame. It has a plant-based diet, unlike nearly all other spiders, which subsist predominantly on meat. B. kiplingi feasts on the nutritious nubs of Central American acacias, which the trees produce to feed their colonies of guard ants. The ants protect the trees from predators, but the spiders have learned how to swoop in and steal the nubs without providing any symbiotic benefit. The spiders will also eat nectar and ant larvae, and when times are tough, they’ve been known to practice cannibalism.

3. ARACHNURA HIGGINSI // THE SCORPION-TAILED SPIDER

Arachnura higginsi spider
Peter Woodard // Wikimedia Commons // Public Domain

Two phobias for the price of one! Found only in Australia, the scorpion-tailed spider is so named because adult females have a long, thin appendage on the tip of their abdomens. (Males and juveniles lack this structure.) The females can arch this bendable tail over their backsides, which gives them the appearance of irate scorpions and prompts would-be attackers to keep their distance. But it’s all an act: The tail cannot sting and Arachnura higginsi is mostly harmless to humans.

4. CAEROSTRIS DARWINI // DARWIN’S BARK SPIDER

The male Darwin’s bark spider is eager to please. Really, really eager. The diminutive males exhibit what some scientists have called “a rich sexual repertoire” to their much larger mates. During sex, males nibble on their partners’ genitals or immobilize them with a web of silk before getting busy. Males will also detach their own sexual organs inside their mates to prevent females from mating with others. Researchers muse that this unusual behavior grew out of males’ survival instinct: A female Darwin’s bark spider is liable to eat her partner after mating.

5. GENUS SCYTODES // SPITTING SPIDERS

Scytodes thoracica spider
Fritz Geller-Grimm // Wikimedia Commons // CC BY-SA 3.0

Using webs to catch prey is all well and good, but it almost seems tame compared to what spitting spiders do to their victims. To subdue a target, the killers take aim and fire twin streams of venom-drenched silk out of their fangs. At a top speed of 62 miles per hour, the fibers move in a wide-arced, zig-zag pattern. In addition to being coated with poison, this silk drips with a super-sticky glue. Once victims are enmeshed, the glue-covered fibers will shrink, constricting the unfortunate prey. Eventually, the spitting spider will administer a venomous bite and put the trapped entrée out of its misery.

6. GENUS DOLOMEDES // FISHING SPIDERS

Hydrophobic coats and a knack for exploiting surface tension allow these predators to walk on water. Fishing spiders lurk in North America, Europe, Australia, and New Zealand. To hunt tadpoles, aquatic insects, and even small fish, many species of fishing spiders will splay themselves over the surface of freshwater lakes or streams. Then, using hundreds of ultra-sensitive leg hairs, they monitor aquatic vibrations. When prey swims by, the spider homes in on its precise location and dives for the victim, sometimes as much as 18 centimeters below the water’s surface.

7. CYRTARACHNE INAEQUALIS // A “DISCO SPIDER”

This little fellow—which arachnologist Joseph Koh believes is Cyrtarachne inaequalis, a member of the Cyrtarachne orb-weaver spider genus—made a vivid impression on photographer Nicky Bay, who captured its singular light show on film. The orb-weaver’s abdomen exhibits a pulsating movement that appear to show its internal organs working under a translucent membrane, Bay writes. Scientists have suggested that the spiders’ display attracts prey or scares off predators, but how and why C. inaequalis puts on its tiny disco act remains a mystery.

8. GENUS MYRMARACHNE // ANT-MIMICKING JUMPING SPIDERS

Myrmarachne ant spider

Found in tropical and temperate zones all over the world, Myrmarachne spiders pretend to be ants—which predators view as aggressive and not worth the effort—to stay alive. With their elongated heads and hourglass-shaped thoraxes, the arachnids look a lot like various ant species (their Latin name even means “ant-spider”). To help sell the illusion, they’ll wiggle their front legs like an ant’s writhing antennae. Of course, a good actor knows when to break character. If certain Myrmarachne species come across predators that eat ants, they’ll drop the ruse.

9. SUPERFAMILY PALPIMANOIDEA // ASSASSIN SPIDERS

Assassin spiders are so named because most of them eat smaller, sometimes poisonous spiders. To keep their food from biting back, Palpimanoidea have evolved long, skinny, giraffe-like necks. Their tiny heads sport huge sets of jaws. When an assassin spider finds a meal, those jaws impale the target and swing forward at a 90-degree angle. That keeps victims a safe distance away from any of the assassin spider’s sensitive body parts. Before long, the skewered prey will die on one of the distended jaws. Then the feasting can begin.

10. GENUS SELENOPS // SPIDERS THAT GLIDE

Our planet is home to more than 40,000 different kinds of spiders, and luckily for arachnophobes, none of them can fly. But at least one genus can free-fall like champion parachutists. In a 2015 study, biologists documented this unusual behavior by systematically dropping 59 tree-dwelling spiders of the genus Selenops from “either canopy platforms or tree crowns in Panama and Peru.” Ninety-three percent of these arachnids steered themselves towards nearby trees to land safely on the trunks. The researchers speculate that such gliding descents happen all the time in nature. After all, the spiders predominantly reside in trees—and the ability to parachute from one trunk to the next would be a huge asset.

10 Ginormous Facts About Coconut Crabs

Janos/iStock via Getty Images
Janos/iStock via Getty Images

They're huge and antisocial. They will steal your silverware and can rip apart whole coconuts with their claws. Grab a piña colada and enjoy these 10 ginormous facts about the amazing coconut crab.

1. Coconut crabs are colossal.

Native to islands in the Indian and southern Pacific oceans, are truly humongous. They can weigh 9 pounds and measure 3 feet from leg to leg. Coconut crabs are the largest land-living arthropods—the phylum of joint-legged creatures that includes crabs, insects, spiders, and scorpions. Even Charles Darwin was stunned by their “monstrous size.”

But be aware: Occasionally, a viral photo circulates that exaggerates the coconut crab’s size. As biologist Michael Bok explains, the coconut crab in that infamous photo is normal sized, but the trash can is unusually small.

2. Coconut crabs are actually hermit crabs.

Coconut crab
Sandwich, Flickr // CC BY-NC-ND 2.0

Where does such a bizarre animal fit in the animal kingdom? Are they lobsters? Tarantulas? Space aliens? In fact, Birgus latro is a kind of hermit crab.

You may have seen smaller hermit crabs on a trip to the beach—or for sale at a pet shop. They take shelter inside abandoned snail shells, carrying them around as portable homes. But if coconut crabs are hermit crabs, then why don’t they live in shells? Well, they do—when they’re young and still small.

3. Coconut crabs quickly outgrow their borrowed shells.

Like other crabs, hatchling coconut crabs begin their lives floating freely at sea. After about a month of eating and growing, they find a snail shell and move in. The little coconut crabs carry this mobile home as they begin to transition to a land-based life.

A seashell is a nice, protected place to live, but it has its drawbacks [PDF]. As a crab gets bigger, its shell gets tighter—like an old pair of shoes on a kid who’s growing fast. The crab needs to find a bigger shell and make a quick switch. And that larger home will be heavier to tote around.

So, after a year or so of inhabiting shells, the coconut crab makes a major lifestyle change. It crawls out and hardens the parts of its body that were once protected by the shell by regrowing layers of calcium-based tissues, a process called recalcification. Without its old home, it’s free of size constraints. Now, unlike other hermit crabs, it can become enormous.

4. Coconut crabs eat coconuts, of course ...

This might seem obvious from the coconut crab’s name. But if you’ve ever tried to crack open a coconut, you know that it’s a steep challenge. In fact, a lengthy scientific debate once raged about whether coconut crabs were really able to open the fruit. It turns out that they’re up to the challenge—but they don’t just pop open their prize and dig in.

Breaking into a coconut is a mighty ordeal even if you’re a heavily armored crustacean the size of a small dog. Coconut crabs first use their claws to scrape away the fibrous coating. This can take hours or days. Finally, they stab into the fruit at a weak point and rip it open.

This diet helps coconut crabs grow large: those with access to coconuts may be twice as massive as those without. But eating the fruit isn’t essential for their survival. So what other items do the largest land-living arthropods shove into their maw?

5. ... but they also eat dead animals, their own body parts, and each other.

As well as the occasional biscuit, as you can see in the video above. (Note: Do not feed biscuits to coconut crabs.) A coconut crab’s diet may include other tropical fruits, fallen plant material, dead and decaying animals, rats, and other crab species. They’ll even eat members of their own kind. In fact, biologist Mark Laidre says they only relatively recently evolved to eat coconuts—a skill unique to modern coconut crabs—which helps them to eat each other less.

They also eat their own discarded body parts. As coconut crabs grow, they periodically molt their tough outer layer (the exoskeleton) and grow a new one. Once they’re done molting, which takes about a month, they gobble up their own exoskeleton.

6. Coconut crabs have an amazing sense of smell ...

Coconut crabs often forage at night. How do they find food when they’re wandering around in the dark? They sniff it out. These animals have a strong, highly efficient [PDF] sense of smell. In fact, a large portion of their brain is devoted to detecting odors.

7. ... which might explain why they're thieves.

Coconut crabs are also known as robber crabs because they snatch silverware and other objects and carry them away. Some people have even advanced the gruesome theory that Amelia Earhart’s remains are missing because coconut crabs hauled them down into their burrows. The thievery might be tied to that incredible sense of smell. Coconut crabs ignore objects that have been washed clean of scents, suggesting that they may only abscond with things that carry a faint whiff of food.

8. Coconut crabs are pretty antisocial.

Adult coconut crabs live alone in crevices or burrows. They aggressively guard their privacy; a crab entering another’s burrow risks becoming a meal.

But that’s not the end of their antisocial behavior. When coconut crabs emerge to feed, they keep their distance from each other. To maintain their personal space, they’ll announce their presence with ritualized claw waving. Laidre sought to find out if coconut crabs ever gathered together to interact (beyond mating or eating each other). The scientist tethered coconut crabs to one spot and watched to see if any others came to visit. They did not.

9. Coconut crabs carry their developing young under their abdomens.

After coconut crabs mate, females attach their eggs to special appendages and carry them under their abdomens. While the young develop inside the eggs, the females hold onto them, sticking near the edge of the sea so that they can periodically moisten the eggs.

But this care ends when the young are ready to hatch. The females release their hatchlings into the ocean waves. Now the tiny, floating babies must fend for themselves—and only a few will survive to return to land.

10. We need to learn a lot more about coconut crabs.

Coconut crab
Anne Sheppard, Wikimedia Commons // CC BY 3.0

Coconut crabs are little-studied creatures, and we need to know more about them—not just because they’re incredible and have a lot to tell us about biology, but also because we want to keep them around.

They may be huge and heavily armored, but they can be vulnerable. Coconut crabs take an extremely long time to grow big—they can live more than 40 years—and introduced predators such as rats can harm smaller, younger individuals or those in the process of shedding their exoskeletons (when their bodies are soft). Habitat loss has also caused local declines in some areas. The International Union for Conservation of Nature lists the coconut crab as data deficient: That is, we don’t know enough about its locations and populations. That’s why we need to study and learn more about these amazing, otherworldly critters.

‘Water’ in Kansas City Woman’s Ear Turned Out to Be a Venomous Brown Recluse Spider

N-sky/iStock via Getty Images
N-sky/iStock via Getty Images

Susie Torres, a resident of Kansas City, Missouri, woke up on Tuesday morning with the distinct feeling that water was lodged in her left ear. She likened it to the swooshing sensation that can often happen after swimming, WDAF-TV reports.

Instead of waiting for the problem to resolve itself, Torres went to the doctor—a decision that might have saved her from some serious pain. The medical assistant was the first to realize something was alarmingly amiss, and immediately called for backup.

“She ran out and said ‘I’m going to get a couple more people,’” Torres told 41 Action News. “She then said, ‘I think you have an insect in there.’” For many people, the thought of having any live insect stuck in an ear would be enough to cue a small- or large-scale freak-out, but Torres stayed calm.

The doctors “had a few tools and worked their magic and got it out,” Torres said. The “it” in question turned out to be a spider—and not just any harmless house spider (which you shouldn’t kill, by the way). It was a venomous brown recluse spider.

“Gross,” Torres told WDAF-TV. “Why, where, what, and how.”

Miraculously, the spider didn’t bite Torres. If it had, she would’ve ended up visiting the doctor with more than general ear discomfort: Brown recluse bites can cause pain, burning, fever, nausea, and purple or blue discoloration of the surrounding skin, according to Healthline.

Torres may have remained admirably level-headed throughout the ordeal, but that doesn’t mean she’s taking it lightly. “I went and put some cotton balls in my ears last night,” she told WDAF-TV. “I’m shaking off my clothes, and I don’t put my purse on the floor. I’m a little more cautious.”

Is this the first time an insect has posted up in the ear of an unsuspecting, innocent human? Absolutely not—here are six more horror stories, featuring a cockroach, a bed bug, and more.

[h/t WDAF-TV]

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