Most Bizarre Marine Animals in the World

By Kate BoveLast Updated Jul 24, 2020 8:14:15 PM ET
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Believe it or not, humans have only explored about 5% of the ocean. In fact, we know more about the surface of Mars, a planet millions of miles away, than we do about our very own seafloor. Despite how little we know, researchers have managed to stumble upon thousands of bizarre aquatic creatures that belong in the trippiest sequences in Tim Burton’s Alice in Wonderland (2010).

If you want to see just how strange sea life gets, there’s no deep-diving necessary. Check out our list of the most bizarre marine animals in the world.           

Leafy Seadragon

Ornately camouflaged, this little fish has thin, leaf-like appendages stemming from its body. Although it seems like a video game designer created a fun combination of a seahorse and an office plant, the leafy seadragon isn’t a character from the Pokémon universe. The leaf-shaped protrusions have a purpose and help this creature blend in with the kelp formations it calls home.

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The leafy seadragon calls the waters off southern and eastern Australia home, but it’s not all sunshine and rainbows in Oz. These animals were once so appealing to locals that divers scooped them up and kept them as pets. In the early ‘90s, the Australian government saw just how much this adoption process was devastating the seadragon population and officially protected the species.

Another (more) fun fact: Even though the leaf projections seem a bit like fins, seadragons don’t use them for movement. Their actual fins are hard to spot because they’re thin and nearly transparent.

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Bioluminescent Octopus

The bioluminescent octopus looks like it just stepped onto the Grid in Tron: Legacy (2010), ready to mount a light cycle. But this glow isn’t part of a costume. Much like a firefly, a chemical reaction occurs in this organism’s body, creating that otherworldly glow — or bioluminescence. The blue-green light forms in the 40 or so suckers, or photophores, that run along the octopus’ underarms.

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Not much is known about this deep-sea dweller. It hangs out in the Atlantic Ocean and eats small crustaceans, and its longest tentacle extends just over a foot in length. It’s also believed that it doesn’t emit light all of the time, as is the case with most bioluminescent organisms. Some animals glow to attract mates, lure in prey, or to protect themselves from predators. At this point, scientists are still debating the primary reason this octopus glows.

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Jawfish

These krill-eating fish live in the warm waters of the Carribean Sea and the southwestern part of the Atlantic Ocean. Because they live around the edges of coral reefs, there’s not much to shelter these fish, which is probably why nature got creative. Using their large, gaping mouths, jawfish dig into the sand and build burrows.

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They float above or hang partially out of their burrows, ready to snatch prey as it drifts by. Of course, staying close to home provides an additional benefit by allowing these fish to quickly dive back into their burrows when predators turn up. With the burrow being so instrumental to its survival, the jawfish stays on top of the yard work. They line the opening of the hole with pebbles — even stealing rocks from their neighbors — to prevent a cave-in.

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But the strangest use for their gaping mouths is the real surprise. As pictured here, male jawfish carry eggs inside their mouths until they hatch. Hopefully they aren’t into caviar.

Fathead (Blobfish)

Ah, the blobfish: part-meme, part-Grumpy-Cat-of-the-sea, and part-Kate McKinnon character. Called everything from "Mr. Blobby" to "a Botoxed potato," this creature infamously won the title of earth’s most hideous species in an online poll. Sure, this gelatinous lump looks more like a gummy candy left in the hot sun than a fish, but the blobfish is also one of Earth’s most misunderstood species.

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Rest assured, this internet sensation can swim, ambush prey, and generally thrive — but only at depths of about 3,000 feet. The blobfish’s gelatinous body allows it to withstand the pressure of living so deep in the sea, but, once it surfaces, the blobfish can’t support its own weight and kind of "splodges," as one scientist put it when talking to Smithsonian Magazine.

The blobfish was first discovered when researchers trawled the ocean floor, looking for new species. Marine ecologist and photographer Kerryn Parkinson recalls netting it, saying, "He looked so human! [And] had that certain charisma that demands attention." This most likely remains the nicest thing anyone has ever said about a blobfish.

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Turritopsis Dohrnii (“Immortal” Jellyfish)

Known by researchers (and Latin enthusiasts) as Turritopsis dohrnii, the Immortal Jellyfish (as we commoners call it) is bizarre in more than just looks. In fact, this jellyfish nabs a spot on our list instead of others of its ilk because it doesn’t have a lifespan — hence, the whole immortality thing. At any moment, this jellyfish can just press the proverbial restart button.

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Jellyfish start out as larvae-like creatures and then settle down and become polyp colonies. For the uninitiated, polyps look almost like strands of kelp or something similar attached to the seafloor. These polyps then branch off and bud into free-swimming jellyfish, like the bell-shaped one pictured here. If the fully mature jellyfish is stressed, wounded, or sick, it can simply revert to its polyp stage — which sounds like the perfect coping mechanism to us.

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Scientists believe this process of rebirth can go on indefinitely, so while the t. dohrnii could certainly be killed by a predator, it is biologically immortal. Forget alchemy, elixirs or long-lost fountains, the secret to immortality is just deciding to start over for this unusual jellyfish.

Kiwa Tyleri (“Yeti” Crab)

Thankfully the yeti crab isn’t named for its towering height. Instead, it looks more like the Abominable Snowman’s pet. This particular type of hairy-chested yeti crab was found off the coast of Antarctica in 2010, five years after the discovery of two other species of yeti crab. This fuzzy-looking crustacean lives in the harshest environment of all.

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As you may have guessed, the waters near Antarctica hover just above freezing. It’s a good thing these crabs aren’t destined for the freezer aisle of your local Safeway, because they have found a unique way to weather the chilling temps. Scientists discovered they cluster — packed as tightly as canned sardines — on hydrothermal vents, the ocean’s natural central heating system.

The water that escapes from these vents is a ridiculous 700 degrees Fahrenheit, which means the yeti crabs have a real balancing act to maintain. If they’re too far away from the superhot liquid, they’ll freeze, but if they’re too close, they’ll fry.

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Though the hydrothermal vents are what keep them warm and allow them to survive, the hair isn’t just for show. As mostly stationary creatures, the yeti crabs use their hair-like structures, or setae, to attract bacteria. Yet another reason we don’t want to see this crab in Red Lobster’s #Crabfest.

Anglerfish

One is the loneliest number, especially if you’re going solo in the desolate, lightless bottom of the sea. Looking understandably irritated, the anglerfish knows this better than any other organism. Although some lucky anglers live closer to the surface in tropical environments, most swim around in the murky waters of the Atlantic and Antarctic oceans, roughly a mile below the surface.

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When you think of an anglerfish, you probably picture their lure, which looks a bit like a lightbulb dangling off a fishing pole. Contrary to popular belief, this feature isn’t used to better navigate the dark depths. Instead, this piece of dorsal spine protrudes over the mouth, allowing the luminous flesh at the end to bait prey.

Surprisingly, only female anglerfish have this feature. So, what about the males? They don’t need lures because they’re full-time parasites. When a male anglerfish finds a female of his species, it latches onto her, eventually fusing with her. Their skin, their bloodstreams — everything ends up connected. The male angler loses its eyes, its organs, its dignity, while the female angler has to deal with upwards of six parasitic mates teething on her.

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Largetooth Sawfish

The largetooth sawfish puts the swordfish to shame — or at least is a bit more unsettling. Growing up to 21 feet in length, these shark-like creatures are actually a type of ray. As you might imagine, that toothed snout is used to find and capture prey, but, unfortunately, this useful feature has its downside.

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Their snouts often get tangled in nets, and some fishermen seek them out for medicinal purposes or to illegally sell their saw-like snouts on the black market. Currently, the most dynamic population of sawfish can be found in Australia, where many organisms live for more than 35 years when they aren’t threatened by humans.

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Unlike most creatures, sawfish don’t discriminate between saltwater and freshwater. Younger organisms often bide their time in rivers and then explore the ocean and estuaries as they mature. Regardless of the body of water they choose, we sure wouldn’t want to meet a sawfish in the wild.

Red-Lipped Batfish

Native to the waters off the Galápagos Islands and Peru, the red-lipped batfish always seems a bit shocked, as if you’re constantly rushing it out of the bathroom before a big night on the town. The fish has that hands-gripping-the-vanity, shocked to running late look. In reality, the red-lipped batfish isn’t rushing off anywhere because it’s not a good swimmer. Instead, the pectoral fins of this creature help it "walk" along the ocean floor.

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Biologically speaking, scientists aren’t too sure what the red lips are for, but they do have some guesses. Chief among them is that the lips are meant to attract mates, much like a bright show of feathers on a bird, or the colorful scales on a fish.

Another fun feature? Like other anglerfish types, this fluorescent-mouthed animal has one of those lovely lures dangling off its head, but only when it reaches adulthood. When a batfish matures fully, its dorsal fin becomes a spine-like projection, allowing it to attract prey more easily.

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Vampire Squid

The scientific name for this next creature is Vampyroteuthis infernalis — which translates to "vampire squid from hell." Even though the name evokes horror at its finest and most gruesome, this cephalopod isn’t too terrifying. It features characteristics from both octopuses and squid, but it doesn’t have some of their more definitive traits. For example, its muscles can’t control changing color, nor can it excrete ink. However, it does have a few somewhat creepy features.

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First, there’s those haunting, blue eyes. The vampire squid probably gained its unconventional name due to its unconventional eyes. In addition to having that soul-penetrating quality, the eyes are just really huge. In fact, this squid has the largest eye-to-body ratio of any known animal in the world.

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Another interesting feature is the webbing that connects the squid’s arms, making it look a bit like a wayward umbrella — or maybe a vampire’s wing-like cape. To snatch pray, it extends two additional sticky filaments from pockets in the web.

Growing to only a foot in length, these relatively small cephalopods keep to themselves, moving slowly through the ocean’s depths. When threatened, the vampire squid tucks into what is called "pineapple position" to protect its head. If that doesn’t work, it thrashes its arms wildly to confuse predators. Adorable or bizarre? You decide.

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Terrible Claw Lobster

With one smaller, toothed claw and one more frightening, elongated one, this deep-sea crustacean looks a bit like a cross between a lobster and your trusty pocket knife. But there’s no need to worry. This little creature probably won’t do much damage if you encounter it — it’s only an inch and a half long on average. Discovered back in 2007 in waters near the Philippines, the reason this lobster has such a specialized claw still evades scientists to this day.

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Ron O’Dor, who works for Census of Marine Life, told NPR that "no one has ever seen a lobster with such divergent claws." As you may know from chowing down on lobster, most species have asymmetrical claws, but the discrepancy is never this apparent — and the claws aren’t usually toothed like these. The claw could have a range of uses from defense to duking it out for a mate.

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Another possibility? The claw might play a role in regulating the body temperature of the lobster, much like the notably huge claw of the fiddler crab.

Flamingo Tongue Snail

Contrary to the image conjured by its name, the flamingo tongue snail isn’t always bright pink. Although a pink coloration is possible, this small marine snail is perhaps better known for its bright orange hues and black spots. (This makes us think leopard snail would be a better name, although neither seems especially fitting.) Surprisingly, the lively colors aren’t part of the snail’s shell, but rather the soft tissue of its body, which is often wrapped around the shell’s exterior.

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It may seem strange for an organism to have a shell and then not use it for protection, but the flamingo tongue has a few more tricks up its metaphorical sleeve. This predator specializes in chowing down on soft coral. As it crawls along an expanse of coral, it eats away the tissue, leaving a skeleton behind. The flamingo tongue uses the chemicals it ingests from the coral to create a poisonous, chemical defense against predators.

So while wrapping its brightly-colored body around its shell seems strange at first, it’s actually the animal world’s way of signaling danger to other species.

Christmas Tree Worm

Christmas tree worms aren’t named after the thing they eat, so you can continue to deck the halls without fear. Instead, these marine animals are named for the tree-shaped crowns that protrude from their tubelike bodies. Brightly colored and made up of hair-like features called radioles, these crowns come in pairs, making it look like two Christmas trees are blooming from the worm’s body.

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These fir tree-looking appendages help the worm snag microscopic plants and plankton for dinner. Like an actual tree, the crowns are instrumental to the respiration process, a feature that is immensely helpful since the worm generally doesn’t leave. Instead, it burrows into coral, hiding most of its body. With only their crowns exposed, the worms are able to duck back into their burrows pretty quickly if a predator approaches.

Marine Hatchetfish

This deep-sea fish derives its name from its flattened body shape, which resembles the blade of a hatchet. You may think you recognize this particular fish, but the marine hatchetfish is different from the freshwater hatchetfish, which you can often find floating around in your local aquarium. Although freshwater hatchets look fairly innocuous, the marine hatchet isn’t something you’d want to bump into in the deep.

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Like many animals that prowl the depths of the ocean, the marine hatchetfish has bioluminescent organs. For this particular species, a pale blue light glows from its stomach. This glow looks a lot like daylight filtering through the water, hiding hatchetfish from predators that would otherwise hunt them from below. This particular type of bioluminescence is known as "counterillumination."

Dumbo Octopus

This deep-sea "umbrella" octopus was named after its fins, which resemble the infamously large ears of Disney’s loveable pachyderm, Dumbo. This creature’s arms are all connected by a web of skin, making it look like an open umbrella when its arms are spread. This combination of features allows them to move through the depths of the ocean with ease. By flapping its ear-like fins, the dumbo octopus pushes its body through the water and then uses its arms to steer.

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Fond of depths of at least 13,000 feet below the ocean’s surface, the dumbo octopus lives deeper in the water than any other octopus. This means they live a fairly unthreatened life. Marine mammals and deep-diving fish like dolphins, tuna, and sharks may go after them from time to time, but the dumbo octopus doesn’t have to worry too much about human interference.

Because the deep sea is vast and lonely, the dumbo octopus is always ready to mate when it bumps into another of its species. The female dumbo octopus carries eggs at different stages of development and has the ability to store sperm for a long time after mating. This allows the female octopus to wait until environmental conditions are perfect before laying its eggs on the rocks that jut out from the seafloor.

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Pycnogonida Sea Spider

Sea spiders are found in the Mediterranean and Caribbean seas as well as in the Atlantic and Arctic oceans. They look quite a lot like land spiders — or maybe a mix of land spiders and crabs — but they’re often much larger. (Unless, of course, you’re comparing them to Australia’s plethora of larger-than-average spiders.) Sea spiders can grow to be nearly 3 feet long and weigh as much as a pound. Yikes!

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If a spider that’s a yard long isn’t already too much to handle, then how about throwing in a little poison to make things interesting? That’s right — these creatures contain poison in their legs. Long story short, if arachnophobia is your weakness, you may want to avoid the seafloor.

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Although they’ve been known to tread water, sea spiders generally walk along the bottom of the ocean, crawling around plants and coral in search of food. Their main meal? Sponges and not flies, which makes us thankful. No one wants to imagine what a sea fly would look like.

Googly-Eyed Stubby Squid

The googly-eyed stubby squid looks like something you made in an arts and crafts session at summer camp — or maybe like a cheap, rubber toy you got out of a vending machine at the local bowling alley. Just look at those eyes; they almost seem painted on. Despite the strangeness of this creature, its cuteness is undeniable. When scientists spotted one off the coast of California in Monterey Bay for the first time, they couldn’t stop giggling. And who could blame them?

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Though they’ve been dubbed a "squid," these creatures are actually more closely related to cuttlefish. In addition to eight short arms, they have the two retractable tentacles — common to most squid — that are used to capture prey, such as shrimp and crabs.

Tiny and charming, a stubby squid only grows to about 5 inches in length and spends much of its time resting on the seabed. When it does move, it expels a jet of water from its body, often leaving behind a blob of ink if it feels threatened. In addition to an ink-defense strategy, the stubby squid also enjoys taking shelter. After settling into a hollow on the seafloor, the stubby squid will cover its body in sand until only those trademark eyes are exposed.

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Venus Flytrap Anemone

Found mainly in the deep water canyons of the Gulf of Mexico, the Venus flytrap anemone is strangely mesmerizing. Maybe it’s because it resembles its terrestrial namesake so closely, or maybe it's the hypnotic way it sways in the water. With a stem-like body and disk-shaped mouth, the Venus flytrap anemone — like other anemones — looks a lot like a flower.

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Of course, the land-loving Venus flytrap is a flower, but the marine version is an animal, through and through. The creature’s strange appearance is for more than just looks. Because the anemone is a stationary creature, it collects food that drifts by.

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The anemone’s disk-like mouth folds in half (think pita pocket), allowing it to trap its food. And those tentacles that ring the "mouth" area? Those also help capture the detritus that floats on by, but, unlike the terrestrial plant’s tentacle-like appendages, these don’t trigger the anemone to snap its "mouth" closed.

Fangtooth

The origin of the fangtooth’s name certainly isn’t a mystery. Although many deep-sea fish seem to have a terrible underbite — not sure how that helps them survive the dark, but that’s okay — the fangtooth certainly has the most unhinged jaw. Thanks to their gaping mouths and rows of long, pointed teeth, the fangtooth is great at snatching prey that drifts through the ocean’s depths.

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But it’s not all about ambushing prey that ambles by — the fangtooth enjoys the hunt. At night, fangtooths have even been known to venture toward the surface to snag a few crustaceans. It’s always good to have a changing, balanced diet, after all.

Something that sets fangtooth fish apart from other deep-sea creatures on this list is their distinct lack of bioluminescence. Some bioluminescent animals use their glow to communicate or as a defense mechanism, while others use their light to attract prey. Without this glowing advantage, the fangtooth is forced to rely on its sense of smell.

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While all of these qualities make this fish seem plenty horrifying, there’s nothing to worry about. Despite their impressive teeth and penchant for biting, fangtooth fish only grow to about 7 inches in length.

Nudibranchs

There are about 3,000 different species of nudibranchs — and all of them are wild looking. The regal sea goddess nudibranch (pictured) definitely ranks up there among the strangest-looking (and the best-named). These soft-bodied mollusks, which are commonly called "sea slugs," shed their shells after they grow out of their larval stage, revealing a mix of beautiful colors. Although their name is meant to be all-encompassing for a wide-range of creatures, the term nudibranch is also incredibly apt, as it comes from a combination of Latin and Greek words that mean "naked gill."

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Why is this an appropriate epitaph? Well, these sea slugs actually breathe through branchial plumes on their exposed backs, one of the features that unifies the variations of nudibranchs. Another trait they all share is their appetite for meat: All known nudibranchs are carnivorous, feeding mostly on sponges. Every once in a while, these shell-less snails have been known to eat one another’s eggs, making them occasional cannibals.

Without eyes, nudibranchs rely on other senses and features to navigate their surroundings. Like most animals with striking color schemes, nudibranchs release toxic chemicals when threatened.

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Whitemargin Stargazer

The whitemargin stargazer is aptly named: It burrows into the sea floor, leaving only its wide eyes — situated on top of its head — exposed to the surface. Of course, the stargazer isn’t actually interested in astronomy. Instead, it gazes up, looking for prey to snatch and, in classic ambush-style, grabs anything that swims by.

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Native to the waters near Indonesia, Fiji, and Samoa, these bizarre fish have more than just their uniquely-positioned eyes going for them. In fact, stargazers have a sort of "fishing lure" in their mouths. This feature, which looks a bit like a fleshy worm, is used to entice prey. Once a fishy victim is distracted by the lure, the stargazer strikes.

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Psychedelic Frogfish

Frogfish are actually members of the anglerfish family but live in most tropical climates. Most types are covered in spinules or other appendages that look a bit like kelp, seaweed or coral. These features help them camouflage more easily, a tactic they rely on not only to hide from would-be predators, but also to surprise their own prey. By blending in and moving slowly, frogfish can pull a fast one on prey — so fast, in fact, that scientists estimate a frogfish snatches its victim in about 6 milliseconds.

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The psychedelic frogfish is certainly something special — and even more bizarre-looking than its brethren. Instead of blending in with clusters of algae, these frogfish take on the complex, swirling patterns of coral. Even those haunting eyes disappear into the endless eddies of color.

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Unlike others in its family, the psychedelic frogfish doesn’t have any sort of lure drooping from its head. It just waits, the old fashioned way, to ambush prey that swims by. True to its name, this fish "hops" along, using its fins to push off from the seafloor like a frog.

Ornate Wobbegong

With a flat head and stocky body perfectly designed to lie on the seafloor, the ornate wobbegong is actually a type of carpet shark. Like other marine camouflage enthusiasts, it operates as an ambush predator and will wait around the algae-covered rocks in bays or in the shallows surrounding coral reefs until prey passes close enough to attack.

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Generally speaking, the wobbegong swallows its victims whole, but, if the prey is too large, this strange fish will hold the struggling prey in its jaws for days. When the prey finally dies, the wobbegong gulps it down.

Found off the coast of Australia, these carpet sharks can grow nearly 10 feet in length. Unlike other animals on this list, they have been known to bite humans, although researchers believe this happens more out of shock than anything else. The ornate wobbegong is a nocturnal creature, meaning it is relatively inactive during the day when human contact is most likely. When startled, the wobbegong may snap at a human diver, but although painful, the bite doesn’t lead to a full-on Jaws (1975) situation.

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Box Jellyfish

The box jellyfish is most known for its deadly venom. If you’ve ever visited a beach in Australia — particularly any northern beaches during the wet season — you’ve probably seen signs that warn visitors of the presence of this lethal creature. Dubbed the most venomous marine animal known to mankind, even the box jellyfish’s nicknames — sea wasp and fire medusa — should be enough to keep you miles away.

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A full grown specimen can measure up to 7 inches along each box side, but its venom-bearing tentacles are roughly 9 feet long. That’s right — these jellyfish have quite a long reach. Each box "corner" has about 15 of these tentacles, each covered in 5,000 stinging cells. To make matters worse, these creatures are a pale blue, almost transparent color, meaning they’re nearly invisible in Australia’s picturesque, clear waters. In fact, for years no one knew what was causing the deadly stings.

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Since 1884, the box jellyfish has caused at least 63 deaths in Australia. What makes this creature’s venom so deadly? For one thing, it’s a triple threat. The venom has cardiotoxic, neurotoxic and dermonecrotic properties. What does this mean? It can cause cardiac arrest in minutes, cause a victim to go into shock from the pain and drown and cause the skin to actually die.

Our advice? Read those warning signs and take them seriously.

Boxfish

Surprise, surprise — the boxfish is box-shaped. Its body is also very tough and rigid, almost like an armor. In theory, the distinct shape and plated body could seem a bit detrimental to the fish’s ability to move, but this creature has found a way around all that. Its style of swimming is known as ostraciiform locomotion, which is a fancy way of saying the fish’s tail does the bulk of the work.

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Despite its unique shape, the boxfish is kind of your average Joe. Its diet consists of what you might expect, like sponges, mollusks, and crustaceans. It has a bright yellow color, but that color fades with age. Nothing too out of pocket there. As with other colorful animals on this list, the boxfish is surprisingly poisonous, releasing a neurotoxin when injured or stressed.

Perhaps the strangest thing about the boxfish — besides that unbelievable shape — is that Mercedes-Benz unveiled a bionic concept car that was inspired by the boxfish and its alleged agility in 2005. Acknowledging this inspiration, the folks at Mercedes-Benz said the boxfish is "a prime example of the ingenious inventions developed by nature over millions of years of evolution."

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Hydrothermal Vent Snail

To those in the know, the hydrothermal vent snail is also known as the scaly-foot gastropod, a name that makes it sound a lot more off-putting and bizarre. This marine mollusk makes its home on hydrothermal vents found in the Indian Ocean at depths of about 2,500 feet below the surface. Because the vents it calls home are rich in metal ores, the snail was placed on the endangered list in 2019, making it the first species to be declared endangered due to deep-sea mining.

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Besides that alleged scaly foot, the most striking feature of the snail is its unique shell, which consists of three protective layers. The outermost layer is made up of iron sulfides, while the innermost is made of aragonite. (Sadly, no adamantium here. Sorry, Wolverine.)

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These layers help the snail absorb mechanical shock — like if a clawed predator tries to put the squeeze on the shell, the snail will most likely withstand it. Even more impressive? Other components in the shell help to dissipate heat. Between all the forceful attacks and the ever-changing volcanic vents that craft the snail’s environment, this creature withstands a lot. All of these elements have led military researchers and scientists to develop a keen interest in this animal.

Lionfish

Native to the Indo-Pacific, the carnivorous lionfish is now an invasive species that has infiltrated the Atlantic Ocean. You may recognize this feisty fish from home aquariums — after all, those intricate fins are something to marvel at — but they are less fun to look at when they’re wrecking natural reefs. As the name suggests, lionfish are a top predator, and this has had lasting effects on the delicate ecosystems of coral reefs.

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Thanks to their flashy looks, predators are more hesitant about chowing down on them. In the wild, flashier often translates to more dangerous, so who can blame them? The lionfish’s spines contain venom glands. If stung, you (or an unsuspecting marine predator) would experience extreme pain, respiratory issues, and paralysis.

These creatures aren’t afraid to take the lion’s share of food and resources and have been known to chow down on more than 50 species of fish. To make matters worse, they feed on animals that help support the reef’s stability, meaning that seaweed has run rampant and overtaken some reefs in the Caribbean and southwestern Atlantic.

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Japanese Flying Squid

Native to the waters off Japan, China, and Russia, the Japanese flying squid has now moved across the Bering Strait to the waters off Alaska and Canada as well. These small squid that only live for about a year are known for their ability to fly. You read that correctly — these marine animals take to the skies on occasion.

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Photo Courtesy: @RateSquids/Twitter

Although rumors of this animal’s strange ability had run rampant for years, their flight was only recently captured on camera. Since the first sighting, researchers have observed the flying squid fly into the air nearly 100 feet above the surface of the ocean. Essentially the squid has a siphon, or muscle, that takes in water and then pushes it out. It’s believed this method of jet-propelled travel helps the squid avoid predators and save energy as they travel across enormous expanses of ocean.

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Stonefish

Venture with us back to Australia’s Great Barrier Reef for a look at another deadly creature. The stonefish is known as the world’s most venomous fish, so between that and the box jellyfish, we’re not sure surfing in Australia is worth the risk. Using its dorsal fin spines, this creature can inject a victim with enough venom to kill an adult human in less than an hour.

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Photo Courtesy: Wild Horizons/Universal Images Group/Getty Images

Even though the stonefish has this venom at its disposal, it doesn’t inject its prey with the deadly substance. It prefers a good old-fashioned ambush, using jaws that are so powerful they can suck most suppers down whole. That said, the venom is meant to keep predators at bay — from other fish to humans looking to nab a stonefish for an aquarium.

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Like other ambush predators, the stonefish is great at the art of camouflage, often settling into the coral and rocks of the seafloor. In fact, these creatures are so good at blending in that algae will grow on their bodies.

Asian Sheepshead Wrasse

With the ability to grow more than 3 feet in length, the Asian sheepshead wrasse is one of the largest of its species. It lives in the western Pacific Ocean, swimming off the Korean Peninsula, China, and Japan. Its most striking feature? Well, that can’t easily be narrowed down to just one element. After all, its unusually bulbous chin has a giant forehead to match. Young wrasses, which are orange in color, don’t have these protrusions, which gives a whole new meaning to "growing into" your facial features.

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Photo Courtesy: @Rainmaker1973/Twitter

Not much is known about the life of this wrasse. Researchers believe they have long lifespans and don’t reproduce as often as other species. A few years ago, a BBC Earth crew captured footage of a wrasse undergoing a transformation. This species is called "hermaphroditic" by scientific researchers, meaning it has both male and female organs. Although other wrasses found off the California coast transition from female to male as they mature, it is unclear what this organism’s development cycle is like.

Nonetheless, a longer lifespan and a longer time between reproductive cycles often make species prime candidates for overfishing and eventual endangerment.