35 Scary Sea Creatures We Hope to Never Encounter

These scary sea creatures have the biggest teeth, sharpest spines and creepiest eyes under the ocean.

Every summer, humans around the world casually step into the ocean for a swim. But it makes no sense. As adorable as baby dolphins are, there’s a lot more out there than friendly sea critters. It’s like walking into the living room of sharks, eels and dozens of other scary sea creatures that would love to eat us. And we do it voluntarily. Why?!

Even worse, we’ve only explored 5 percent of the ocean. That means the scary sea creatures on this list are less than 5 percent of what’s out there. Can you imagine what other ocean animals might be lurking in the deep sea?

Warning: If you do plan on spending your summer riding the waves, maybe sit this one out. Otherwise, you might be too scared to ever go in the water again.

Frilled Shark

3dsam79 / Getty Images

Scientific name: Chlamydoselachus anguineus

What makes this sea creature scary: The frilled shark is often called a “living fossil,” and we get why. Its features are eerily similar to that of some kind of primitive eel. Its jaws come with not one, not two, but 25 rows of curved, razor-sharp teeth.

Before you get too worried, the odds of running into a frilled shark on a snorkeling trip in Mexico are next to zero. These scary sea creatures rarely travel closer to the surface than 390 feet deep, often residing at more than three times that depth.

Frilled Shark in Action

Deep-Sea Dragonfish

Woods Hole Oceanographic Institution (WHOI) / Facebook

Scientific name: Grammatostomias flagellibarba

What makes this sea creature scary: In the darkest, deepest corners of the ocean, not much can survive. The pressure is crushing, and the lack of light and oxygen makes survival extremely difficult. The deep-sea dragonfish makes do with unique adaptations, including photophores that produce light to attract prey.

They’re some of the scariest-looking sea creatures around, with fanged jaws and a flexible spine that enables them to eat larger prey than one might expect.

Pacific Viperfish

David Csepp / Wikipedia

Scientific name: Chauliodus macouni

What makes this sea creature scary: Anything with long, needle-like fangs is creepy in our book. The viperfish often sits still, deep, deep below the surface. Like the dragonfish, its photophores lure in unsuspecting prey. When its lunch gets close enough, it strikes.

If that’s not creepy enough, its fangs don’t fit all the way inside its mouth. Instead, they have a bulldog-like bite, just way less cute.

Pacific Viperfish in Action

Atlantic Wolffish

Bjørn Christian Tørrissen / Wikipedia

Scientific name: Anarhichas lupus

What makes this sea creature scary: Are you sensing a theme? Most of the scary deep-sea creatures are adapted for quick strikes and quick kills. There aren’t any vegetarians down on the ocean floor because there isn’t really any vegetation at all.

Wolffish are no exception to this rule. They have several fang-like teeth in the front, followed by three more rows of teeth set in a powerful, crushing jaw. Even their throats are armed with serrated teeth. If that’s not bad enough, the wolffish is shaped like an eel and can be as long as a grown human is tall.

Fangtooth Fish

Citron / Wikipedia

Scientific name: Anoplogaster cornuta

What makes this sea creature scary: Fangs are freaky, especially when there are so many. The fangtooth fish looks like a much uglier piranha. Its fangs are literally prize winners; the fangtooth’s teeth are the largest of any marine animal in proportion to its size.

The poor, creepy sea creature can’t even close its mouth all the way. Luckily, it lives several thousand feet below sea level, where no one can judge its toothy facial expressions.

Fangtooth Fish in Action

Anglerfish

spyder24 / Getty Images

Scientific name: Lophiiformes

What makes this sea creature scary: You probably recognize this one from “Finding Nemo.” But, unfortunately, the anglerfish wasn’t invented by Pixar. It functions exactly as depicted in the movie, attracting prey with its bobbing lure, much like a fisherman.

And it’s not only small, Nemo-like fish that should be afraid. Anglerfish have such flexible jaws that they can consume prey that’s twice their size.

Black Swallower

Wikimedia

Scientific name: Chiasmodon niger

What makes this sea creature scary: Most bottom dwellers are too small to be a threat to people even if a human did find themself face to face with one. That doesn’t stop them from being scarier than an entire stack of horror films, though.

The black swallower looks like a sea monster that ate another sea monster. It’s slender at first but only until it has dinner. Then, its stomach can expand up to 10 times its original size. If this ocean animal overdoes it, its prey can actually start rotting before the black swallower has yet to finish digesting it. This creates so much gas that the fish is forced to the surface, where it meets its untimely death.

Black Swallower in Action

Snaggletooth

Peter Marriott / Wikipedia

Scientific name: Astronesthes

What makes this sea creature scary: Can you guess why it’s called a snaggletooth? This scary-looking sea animal has a bioluminescent projection on its chin to attract prey.

This adaptation is very common among deep-sea dwellers, but it’s still creepy. The pin-like teeth and soulless black eyes might have something to do with it, too.

Monkfish

Mike Beauregard / Wikipedia

Scientific name: Lophius

What makes this sea creature scary: Why anyone would name this fish after a monk is beyond us. There’s nothing zen about the monkfish at all. Their wide mouths have strips of long, curved teeth that help them wolf down massive prey.

They don’t only live in the deep sea either, so divers are a bit more likely to run into the monkfish than most other fish on this list.

Monkfish in Action

Grenadiers

Monterey Bay Aquarium Research Institute / Wikipedia

Scientific name: Macrouridae

What makes this sea creature scary: Rattail fish, also known as grenadiers, are some of the scariest sea creatures in existence. Unlike most deep-sea fish, this particular predator is fairly large, with adults measuring around 3 feet in length.

Their eerie, blue eyes can spot even the tiniest flicker of light, allowing them to catch other bottom dwellers that use bioluminescence to catch prey of their own. Check and mate.

They live around the world at depths of between 600 and 13,000 feet.

Barreleye

3dsam79 / Getty Images

Scientific name: Opisthoproctidae

What makes this sea creature scary: Honestly, this one is more cool than creepy. While it looks like the barreleye’s eyes are in the front of its face, they’re actually located in a see-through dome of soft tissue on top of its head. It looks a little like eyeballs encased in flavorless Jell-o.

This unusual sea creature was first documented all the way back in 1939, but no one was able to snap a photo of one alive until 2004!

Barreleye in Action

Sea Spider

Bernard Picton / Wikipedia

Scientific name: Pycnogonida

What makes this sea creature scary: Ew, ew, ew. If you thought you could escape spiders by jumping into the water, think again.

There are more than 1,300 species of sea spiders, residing everywhere from shallow coral reefs to thousands of feet below the surface. Some of them have legs that span more than a foot. Shudder.

Vampire Squid

Wikipedia

Scientific name: Vampyroteuthis infernalis

What makes this sea creature scary: Thankfully, the vampire squid doesn’t suck blood. It’s named after vampires because it can survive with virtually no light and no oxygen. It lives nearly 3,000 feet below the surface, where the oxygen saturation is as low as 3 percent. Most fish would be dead in minutes, but the vampire squid? Totally unphased.

Ranging from red to black in color, the eight-armed sea creeper has rows and rows of spines on each tentacle. If you want a more creative Halloween costume this year, skip the vampire outfit and go as a vampire squid. They’re just as scary, and unlike vampires, they’re actually real.

Vampire Squid in Action

Colossal Squid

Benjamindancer / Wikipedia

Scientific name: Mesonychoteuthis hamiltoni

What makes this sea creature scary: Giant squids aren’t urban legends, but movies have definitely exaggerated their size and ferocity. But considering they reach up to 45 feet in length, they’re still scary enough to make this list. They have eyes that are bigger than your head and can weigh over a ton. Plus, they’re fearless.

Colossal squids have been known to go after sperm whales. While you’re unlikely to ever come across one, a creature that sees an entire whale as a hearty breakfast is enough to scare us away from the beach forever.

Goblin Sharks

Dianne Bray/Museum Victoria / Wikipedia

Scientific name: Mitsukurina owstoni

What makes this sea creature scary: The goblin shark should have been called the deep-sea nope. It looks like a regular shark but like it’s missing several layers of skin and half its face. That’s because its skin is semi-transparent, so you can actually see some of the flesh beneath it.

This scary deep-sea creature also extends its sinister-looking jaws rapidly forward to grab prey in a split second. It’s, fortunately, not a threat to humans, unless you count the nightmares we’ll be having later.

Goblin Sharks in Action

Japanese Spider Crab

Hans Hillewaert / Wikipedia

Scientific name: Macrocheira kaempferi

What makes this sea creature scary: Most crabs are more tasty than scary. But then, nature went ahead and crossed a crab with a spider. Why would you do such a thing, nature? Who saw an ordinary crab and thought, “Hmm, this would be better if we made its legs 8-feet long and added claws to the end?” No one sane.

One of the scariest sea creatures we’ve seen, the Japanese Spider Crab can weigh up to 40 pounds and can regrow its legs if it loses them.

Giant Isopod

Wikipedia

Scientific name: Bathynomus

What makes this sea creature scary: Have you ever caught a sand crab? Welp, this is a sand crab, just multiplied by about 300. Giant isopods are crustaceans that have been around for thousands of years, and they look pretty terrifying. They have seven pairs of legs, four sets of jaws and can reach 2.5 feet in length.

If you happen to dig one of these up in the sand, run away. It can’t hurt you, but when something straight out of “Jurassic Park” appears, running away seems like the safest plan.

Giant Isopod in Action

Stargazer

Canvasman21 / Wikipedia

Scientific name: Uranoscopidae

What makes this sea creature scary: The fact that this underwater monster is on the plump side makes it appear a little less threatening than the more eel-like additions to this list, but it’s far from sweet and snuggly. Its bland appearance is for a purpose. The stargazer blends in perfectly with the sand on the ocean floor. It just chills on the ground until an unsuspecting fish meanders by.

Then, it opens its massive mouth and chows down. Some species can also deliver mild electric shocks, and most have venomous spines that can further stun and subdue their future dinner.

Bull Shark

Albert Kok / Wikipedia

Scientific name: Carcharhinus leucas

What makes this sea creature scary: Now we’re getting to the scary sea creatures that are actually threatening to humans. While no species of shark intentionally prey on humans, they also don’t have the best vision or the biggest brains. Sharks have been known to mistake swimmers and surfers as seals. By the time they realize their mistake, it’s too late.

The bull shark is one of the most unpredictable and aggressive sharks in the ocean. It’s not the largest, but with an average size of nearly 8 feet and weighing 300 pounds, it’s still plenty big enough to do serious damage. The scariest part? Even out of the ocean, you’re not completely safe. Bull sharks sometimes swim up rivers and can attack in less than 3 feet of water.

Bull Shark in Action

King Crab

Moondigger / Wikipedia

Scientific name: Lithodes maia

What makes this sea creature scary: My, what big spikes you have! While this is far from the scariest sea creature on this list, the spiny king crab is strange enough to turn some heads. These deep-sea crustaceans have an exoskeleton like every other crab, except with sharp, spiny protrusions all over its shell.

Despite their threatening appearance, they’re actually close cousins of the harmless hermit crab. Unless you’re walking around thousands of feet below the sea, you’ll probably never meet one. If you did step on one, however, it would probably do more damage to the crab than to you.

Gulper Eel

Alexei Orlov / Wikipedia

Scientific name: Eurypharynx pelecanoides

What makes this sea creature scary: When we said most of the scary sea creatures on this list weren’t a threat to humans, we meant physically. Psychologically, we’re not so sure. The gulper eel looks like something a kindergartener drew for Halloween. It’s jet black, with a huge, gaping maw that can engulf prey twice its size.

Its tail stretches out to a long, stinger-like point that can flash bright red in the frigid darkness of the deep sea. We’d rather swim with sharks than this thing.

Gulper Eel in Action

Ghost Shark

NOAA / Wikipedia

Scientific name: Chimaeriformes

What makes this sea creature scary: Ghost sharks look like a zombified version of a tuna. We can’t believe any creature was born looking this creepy. We suspect that it was an ordinary fish that met its untimely death in a fisherman’s net, and it rose from the dead to seek its revenge.

Either that or it’s developed some highly specialized adaptations for living in the most uninhabitable place on Earth. Ghost sharks live in almost total darkness, so they rely on vein-like sensory organs to detect the movement of prey. In other words, if you dive down to the ocean floor, a ghost shark can see you before you can see it.

Flying Spaghetti Monster

Catriona Munro / Wikipedia

Scientific name: Bathyphysa conifer

What makes this sea creature scary: The deeper you dive, the weirder things get. It takes something special to make it at the bottom of the sea, which is why such bizarre adaptations pop up. The so-called flying spaghetti monster is a cousin of corals and jellies. A jellyfish’s stinging tentacles are already scary, but this thing takes it up a notch.

The flying spaghetti monster is basically all tentacles. It looks a bit like a pile of plastic bags filled with goo and wrapped in highly aggressive silly string. Luckily, they’re rarely found near the surface, preferring to chill out around 3,000 feet below sea level.

Flying Spaghetti Monster in Action

Sarcastic Fringehead

James Martin / Wikipedia

Scientific name: Neoclinus blanchardi

What makes this sea creature scary: This scary-looking ocean creature is harmless, but we’re going to stay out of its way all the same. The sarcastic fringehead only grows up to 8 inches in length, and it likes to burrow into holes in the sand left by other critters.

They mostly eat squid eggs, but their wide mouth looks like it’s made to eat something much bigger. They’re native to the Pacific Ocean along the coast of California, so divers in the area have a chance at meeting this innocent, albeit icky, sea animal.

Megamouth Shark

opencage / Wikipedia

Scientific name: Megachasma pelagios

What makes this sea creature scary: The megamouth shark isn’t the largest shark, but it’s plenty big enough to be considered ultra frightening. Megamouths are deep-sea sharks that reach up to 18 feet in length. In reality, they’re harmless. They’re rarely seen by humans, and even if you did run into one, it would be extremely unlikely to hurt you.

That’s because it’s in the same family as whale sharks and basking sharks, which prey on plankton and jellyfish. They have rows upon rows of small, sharp teeth, but they’re intended for eating small fish, not people. The reason megamouths are so scary is the way they look. They swim with their massive jaws spread open at all times, sweeping up fish and krill like a vacuum. We’re not sure about you, but no matter how harmless it is, if we saw a dark, truck-sized fish swimming at us with a gaping mouth, we’d be a little concerned.

Megamouth Shark in Action

Ghost Fish

NOAA / U.S. Fish and Wildlife Service

Scientific name: Part of the Aphyonidae family

What makes this sea creature scary: Considering the looks of all the other scary deep-sea creatures we’ve mentioned, the ghost fish is almost cute. Scientists haven’t yet defined what species this fish, is as it was first spotted in July 2016. It was found swimming 8,202 feet down at the Mariana Trench National Monument.

It looks a little like an axolotl, but despite its scaleless skin, it’s a fish, not an amphibian. With ghostly orbs for eyes and partially transparent skin, it hardly even looks real.

Sea Cucumbers

François Michonneau / Wikipedia

Scientific name: Holothuroidea

What makes this sea creature scary: Sea cucumbers are a bit like giant, underwater slugs. While they’re relatively benign, many species of sea cucumber have the ability to release toxins to stun or even kill animals that try to eat them.

While they’re not large enough to seriously hurt a human, it’s best to steer clear of these creepy critters.

Sea Cucumbers in Action

Moray Eel

Johnycanal / Wikipedia

Scientific name: Gymnothorax bathyphilus

What makes this sea creature scary: There’s a reason Ursula selected eels as her evil minions. Aside from resembling sinister, underwater snakes, moray eels have exceptionally sharp teeth and powerful jaws. They move quickly, viciously clamping down on any prey that comes their way. While they don’t hunt people, they can deliver a nasty bite if provoked.

Moray eels are served in some seafood restaurants, but extreme care has to be used during their preparation. Their flesh is toxic and can cause severe illness if prepared incorrectly!

Armored Searobin

NOAA / Wikipedia

Scientific name: Peristediidae

What makes this sea creature scary: Why would a scientist look at this spiny, pink sea flap and name it after a robin? Have they never seen birds? The armored searobin is covered in coral pink scales, and the branch-like projections on its chin attract prey.

Its tail is also lined with spikes to deter predators. Why any creature would even consider eating what resembles a spiny, uncooked chicken breast, we haven’t a clue.

Armored Searobin in Action

Hagfish

Linda Snook, NOAA / Wikipedia

Scientific name: Myxini glutinos

What makes this sea creature scary: Once again, it doesn’t have to be dangerous to be scary. The hagfish has no jaw, so it’s not a threat to people, but that’s where the good news ends. Hagfish are also called slime eels because they produce thick, unappealing goo to deter predators. Mission accomplished, hagfish.

But wait, there’s more! Since they don’t have jaws, they eat by wiggling their way into decaying, underwater carcasses. It’s gross, but evolutionarily speaking, it works. Seventy-six species of hagfish exist today, with some growing up to 40 inches in length.

Highfin Lizardfish

NOAA / Wikipeda

Scientific name: Bathysaurus mollis

What makes this sea creature scary: The highfin lizardfish looks similar to the ghost fish, only way scarier. It has large powerful jaws and knife-like teeth. It’s also pretty large for a deep-sea dweller, growing more than 2-feet long.

It typically resides 2,500 feet below the surface, however, so you don’t have to worry about stepping on one of these on your next vacation.

Highfin Lizardfish in Action

Faceless Cusk

DeepseaOddities / YouTube

Scientific name: Typhlonus nasus

What makes this sea creature scary: We’re not sure what’s worse; a terrifying face or no face at all. The faceless cusk lives around 13,000 feet below sea level, and it’s so dark down there that eyes are pretty much useless. It resembles a giant tadpole, but it has the misfortune of never becoming a cute little frog. Instead, it extends its weird, protruding mouth from under its body, gobbles up its prey and then retracts its mouth once more.

A faceless cusk hasn’t been seen in years, but there’s no reason to believe they don’t still exist.

Slender Snipe Eel

Sandra Raredon/Smithsonian Institution / Wikipedia

Scientific name: Nemichthys scolopaceus

What makes this sea creature scary: The fictional snipe from Pixar’s “Up” is cute. This snipe eel, on the other hand, will haunt our dreams. Resembling a piece of angry ribbon, the slender snipe eel can reach several feet in length while weighing in at less than half a pound.

Its odd, beak-like mouth looks like it belongs on a bird rather than a sea creature. Scientists haven’t quite figured out how it works, but it must work well enough since the snipe eel is still (unfortunately) around.

Slender Snipe Eel in Action

Blobfish

Rachel Caauwe / Wikipedia

Scientific name: Psychrolutes marcidus

What makes this sea creature scary: The blobfish was once named the “world’s ugliest animal,” and it’s a pretty accurate title. It’s part of a group of fish called the fathead sculpins, and none of them are winning a beauty pageant anytime soon.

The blobfish’s bulbous head and fleshy, pink body look unlike any other fish in the ocean. Plus, it doesn’t have a swim bladder. Its body is less dense than water, so it’s naturally buoyant. One particularly photogenic (if you can call it that) blobfish was affectionately named Mr. Blobby. He became a bit of a pop culture icon, inspiring T-shirts, emojis and stuffies in his honor. If you want to see him up close and personal, his preserved body is on display at the Australian Museum in Sydney.

Great White Shark

Terry Goss / Wikipedia

Scientific name: Carcharodon carcharias

What makes this sea creature scary: Did the “Jaws” theme song start playing in your head just now? Same. Great white sharks are arguably the scariest sea creatures in existence. Weighing up to 4,200 pounds and reaching up to 20 feet in length, the great white shark is the ocean’s most fearsome predator.

They possess the biggest jaws of any carnivorous shark, and they’re found in waters around the world, including near beaches frequented by people. While great whites rarely attack people, it’s really, really bad when they do. Even an exploratory bite, when a shark mouths a person just to see what it is, can result in the loss of a limb or life-threatening blood loss. The odds of getting attacked by a great white are slim, but the next time you’re out surfing or kayaking, keep your eyes peeled. Just to be safe.