The Weirdest Looking Sea Creatures Found in the Deep Ocean

We know surprisingly little about the deep ocean or the strange creatures that live there. These unusual animals have evolved without sunlight and survive in complete darkness, resulting in many unusual characteristics. Here are some of the bizarre-looking sea creatures found lurking on the ocean floor!

1. Barreleye Fish (Opisthoproctidae)

Barreleye fish are named for their unique, barrel-shaped eyes. These eyes can rotate, allowing the fish to look both upward and straight ahead. Their eyes also have bright green lenses protected behind a transparent forehead, which gives the fish a futuristic appearance, almost like a sci-fi submarine.

Barreleye fish grow to about 6 inches long and are found in the northeastern Pacific Ocean, living at depths of 2,000 to 2,600 feet below the surface. The yellow pigment in their eyes helps them distinguish between the faint bioluminescent light produced by living organisms and sunlight. This makes it easier to spot the siphonophores and zooplankton that they eat.

2. Fangtooth Fish (Anoplogastridae)

Even though fangtooth fish are only about 7 inches long, their mouths are full of terrifying, needle-sharp teeth. These long, fang-like teeth make it easy for them to catch and trap prey in their mouths. You can find these long-toothed fish in temperate and tropical waters all over the world, living between 1,650 and 7,000 feet below the surface in the mesopelagic and bathypelagic zones.

3. Dumbo Octopus (Grimpoteuthis)

Dumbo octopuses live between 9,800 and 13,000 feet below the surface. These cute sea creatures only grow to about 8 inches tall, but the two fins on top of their heads make them stand out. They look just like the big ears of Disney’s elephant Dumbo, which is how they got their name. Living in the deep ocean is cold and dark, and finding a mate can be quite the challenge. Female dumbo octopuses, however, have a clever trick: they carry eggs at different developmental stages everywhere they go. This means that when a rare encounter with a male octopus does happen, she can make the most of it by fertilizing the most mature eggs she’s carrying at that moment.

4. Vampire Squid (Vampyroteuthis infernalis)

The vampire squid’s scientific name might translate to “vampire squid from Hell,” but these creatures are actually quite gentle. They get their ominous name from the webbing between their arms, which looks a bit like Dracula’s cape. You can find vampire squid in tropical and temperate waters worldwide, living in the mesopelagic zone, over 2,000 feet below the ocean’s surface. As scavengers, vampire squid have a rather peculiar diet: they feast on “marine snow.” This is not actually snow, but rather the decaying bits that drift down from dead animals higher up in the ocean.

5. Hagfish (Myxiniformes)

The hagfish looks like something a witch might have put a spell on — though it’s a fish, it looks more like a super slimy eel with a mouthful of shark-like teeth. There are over 70 species of hagfish, and they vary quite a bit in size, from just a few inches long to up to 4 feet long. Hagfish are scavengers that live around 5,600 feet below the ocean’s surface. They burrow into dead animals and literally eat them from the inside out. Remarkably, they can also absorb dissolved organic matter directly through their skin and gills—a useful adaptation when food is scarce.

6. Bloody-Belly Comb Jelly (Lampocteis cruentiventer)

This crazy-looking sea creature has a heart-shaped body and a deep crimson color that seems to sparkle and glow. However, the jelly doesn’t actually produce its own light. Instead, its “glow” comes from the way light reflects and diffracts off its tiny, transparent hair-like structures called cilia. Bloody-belly comb jellies live between 1,200 and 3,281 feet below the ocean’s surface and only grow about 6 inches long.

7. Japanese Spider Crab (Macrocheira kaempferi)

With a carapace that can reach 16 to 18 inches wide and a staggering leg span of up to 13 feet, the Japanese spider crab truly earns its title as the largest crab in the world. But don’t let its imposing size and appearance fool you; despite looking like something straight out of a monster movie, the Japanese spider crab is a surprisingly mellow creature. This colossal crustacean gracefully drifts along the ocean floor where it calmly scavenges for algae, small invertebrates, and any dead fish it can find.

8. Grenadier (Macrouridae)

The grenadier is often called a “rattail” because of its distinctively long, flat, tapered body. There are over 300 different species of this fish, living in the abyssal and bathyal zones of the world’s oceans. Some live as deep as 13,100 feet below the surface! Grenadiers are scavengers that skim just above the ocean floor, constantly on the lookout for fish and squid to munch on. Since there’s no sunlight where they live, grenadiers have evolved enormous blue eyes that can pick up even the faintest hint of bioluminescence to help them pinpoint their next meal.

9. Goblin Shark (Mitsukurina owstoni)

With an appearance that looks like it swam right out of a terrifying sci-fi movie, the goblin shark is a living fossil found on the ocean floor. This crazy-looking shark has a long, pointed snout that extends out like a fleshy blade above its mouth. Its mouth is also large and packed with countless sharp teeth. But what makes it truly unsettling is its ability to thrust its jaws outward, making it look like a fantastical monster. These deep-sea predators feast on squid, crustaceans, and bony fish. They live around 3,900 feet below the surface in the Atlantic, Pacific, and Indian Oceans.

10. Sarcastic Fringehead (Neoclinus blanchardi)

The sarcastic fringehead is a feisty little fish found in the northeast Pacific Ocean. It is a type of tube blenny—a fish with a long, slender body that makes its home in unusual places. They take up residence in abandoned barnacle shells, worm tubes, and sometimes even discarded soda cans. When they open their mouths, their jaws expand to four times their closed size, revealing a surprisingly colorful interior. Sarcastic fringeheads may only grow 3 to 8 inches long, but what they lack in stature, they more than compensate for in attitude. These fearless fish are quite irritable and will boldly dart out at anything that dares to get too close to their home.

11. Sea Angel (Gymnosomata)

This unusual sea creature appears to gracefully “fly” through the water, flapping what look like delicate, angelic wings. Despite their ethereal appearance, however, sea angels are a type of swimming snail. Those beautiful “wings” are specialized structures called parapodia, which they use to propel themselves through the water. Their gelatinous bodies are transparent, allowing their internal organs to be visible. Some species even glow! But don’t let their heavenly looks fool you. As beautiful as they appear, sea angels are carnivorous predators. They have a particular taste for other sea snails, especially sea butterflies.

12. Atlantic Wolffish (Anarhichas lupus)

With a body that tapers toward a slender tail and a large, round head, the Atlantic wolffish’s bluish-grey, almost zombie-like form looks a bit strange. But what really makes it stand out are the prominent, pointed front teeth jutting out of its mouth, giving it the look of some kind of watery werewolf. As you might guess from its name, this crazy looking fish makes its home along the Atlantic Coast. It particularly loves cold, rocky areas, dwelling as far down as 1,640 feet below the surface. It’s so adapted to the cold that it produces a special antifreeze protein in its blood that ensures that the fish doesn’t freeze in its frigid environment.

13. Blobfish (Psychrolutes marcidus)

The famously “ugly” blobfish looks surprisingly normal when it’s living in the deep sea. It’s only when it’s brought to the surface that it transforms into the rather unappealing blob it’s so famous for. This deep-sea fish lives off the coast of Australia, at depths of around 4,000 feet below the ocean’s surface. At that depth, the pressure is immense — over 100 times stronger than the air pressure we experience on land! To survive in such extreme conditions, the blobfish’s body has many unique adaptations. Unlike most fish, it doesn’t have a swim bladder, which helps other fish to float. Instead, its body is composed of soft tissue filled with fat and water. This adaptation allows the blobfish to withstand the crushing pressure of its environment. However, when a blobfish is brought up to the surface, its body collapses into a gooey mess.

14. Anglerfish (Lophiiformes)

With over 200 species found worldwide, anglerfish are perhaps best known for their iconic “lure,” found only on the females. This specialized, bioluminescent apparatus protruding from the female’s head resembles a fishing pole with a glowing light at its tip. This clever lure attracts unsuspecting small animals in the pitch-black depths of the sea while the rest of the anglerfish remains hidden in the darkness.

15. Sea Pig (Scotoplanes)

Despite its name, the sea pig is actually a type of sea cucumber. But its squishy, pinkish body and its habit of rooting through the mud are why it earned such a fitting nickname. It is a relatively small sea creature, measuring between 1.5 and 6 inches long. Sea pigs have tube-like “legs” on their undersides that help them move across the ocean floor. They also have similar appendages on their backs and around their mouths, which they use to sift through mud and debris, picking out bits of algae and dead animals.

16. Slender Snipe Eel (Nemichthys scolopaceus)

The slender snipe eel is sometimes called a “deep-sea duck” due to its long, narrow snout, which looks like a bird’s beak. It swims with its large mouth wide open, leading scientists to believe it might catch its prey using the tiny, hooked teeth that line its “beak.” Slender snipe eels can grow up to 5 feet long, but their bodies are incredibly thin and ribbon-like, supported by about 750 vertebrae. They are found living in the deep ocean, anywhere from 1,000 to 13,000 feet below the surface.

17. Sloane’s Viperfish (Chauliodus sloani)

Sloane’s viperfish looks like a creature straight out of a deep-sea nightmare. These unsettling fish have glow-in-the-dark bodies and enormous, fang-like teeth, allowing them to prey on animals much larger than themselves. Their jaws can unhinge like a snake’s, and their long, spindly teeth interlock perfectly to trap unfortunate prey inside. Additionally, they can expand their stomachs to make room for bigger meals. This is quite useful when living in the mesopelagic zone, 650 to 3,300 feet below the surface, where food can be scarce, and they might have to go days without eating.

18. Elephant Shark (Callorhinchus)

Elephant sharks, also called plough-nose chimaeras or ghost sharks, have large eyes and a long, prominent snout that ends in a hook-like tip. This snout is incredibly sensitive and helps the sharks find food by detecting the electric fields and movements of prey hidden in the sand. Unlike most fish, elephant sharks do not have any bones; instead, their skeletons are made of cartilage. You can find these crazy-looking sea creatures in the southern hemisphere, with Callorhinchus milii inhabiting the waters around southern Australia and New Zealand, and Callorhinchus callorynchus found off southern South America.

19. Deepsea Lizardfish (Bathysaurus ferox)

The deep-sea lizardfish is perfectly adapted for hunting in the dark. Found between 600 and 3,500 feet below the ocean’s surface, these creatures are among the top predators of their environment and are willing to eat just about anything they can sink their teeth into. The deep-sea lizardfish has a thin, cylindrical body and a flat, lizard-like head, with enormous eyes perfectly designed to detect any light in the perpetual darkness. Its gigantic mouth is packed with multiple rows of long, needle-like teeth, ensuring nothing escapes once caught.

20. Frilled Shark (Chlamydoselachus anguineus)

The frilled shark is a truly bizarre and rarely seen creature that roams both the Pacific and Atlantic Oceans. Growing to about 7 feet long, this living fossil still carries many of the same features of its ancient ancestors, giving us a peek into what prehistoric sea creatures may have been like. The shark’s name comes from its gill slits, which have a distinctive ruffled or “frilled” appearance along their edges. Its body is long and slender, making it look and swim more like an eel than a shark.