Science | Updated: September 26, 2024 | Originally Published: October 29, 2012

See Ten Strange and Mesmerizing Creatures From the Deep Ocean, From Sea Toads to Frilled Sharks

Scientists who explore the depths using submersibles continue to discover amazing animals that inhabit dark waters

A rarely seen whiplash squid swims more than 3,500 feet below the surface of the Pacific Ocean. ROV SuBastian / Schmidt Ocean Institute CC BY-NC-SA

Hannah Waters, Emily Frost; Updated by Joe Spring

By the time the Schmidt Ocean Institute’s research vessel Falkor (too) finished an expedition off the coast of Chile earlier this year, its scientists had amassed a slew of amazing deep-sea discoveries. During the cruise, researchers sent an underwater robot capable of descending more than 14,000 feet below the surface to collect video footage and specimens from seamounts. After analyzing what they had gathered, the international team revealed they had likely found more than 100 new species.

“We far exceeded our hopes on this expedition,” their chief scientist, Javier Sellanes of the Catholic University of the North in Chile, said in a statement in February. “You always expect to find new species in these remote and poorly explored areas, but the amount we found, especially for some groups like sponges, is mind-blowing.”

In addition to several sponges, the scientists documented an awe-inspiring collection of oceanic creatures that included crustaceans with incredibly long arms called squat lobsters, sea toads able to ambush prey with their highly evolved senses, rarely seen whiplash squid that sport bulging eyes and brightly colored spiraling corals.

The revelations made by the recent expedition were just some of the latest in a series of discoveries made in the deep sea—and much more is left to uncover. As the Monterey Bay Aquarium states on its website, scientists know more about the moon than this remote oceanic habitat. What researchers have discovered so far about the animals that inhabit this dark realm is that they have evolved into strange shapes, deploy special camouflage for protection and sometimes even produce their own light via bioluminescence to attract mates or trick prey into becoming an easy meal.

To give you a brief glimpse of the unusual life biologists have found so far below the ocean’s surface, we collected ten of our favorite deep-sea creatures below.

Glowing sucker octopus (Stauroteuthis syrtensis)

Red Octopus — The glowing sucker octopus swims through the darkness. Ocean Portal / David Shale

The eerily beautiful glowing sucker octopus is often found in deep Atlantic waters off the U.S. coast. Stauroteuthis syrtensis uses its fins and the webbing between its eight arms to swim. Rows of glowing bioluminescent suckers trail down those arms and shine in the deep sea. Scientists think these glow-in-the-dark suckers may be used to attract planktonic prey like copepods, miniature crustaceans that are drawn to the light. The octopus is thought to prefer ocean temperatures of roughly 37 degrees Fahrenheit and can be found at depths of more than 13,000 feet. The species has been recognized for more than a century, but only in 1999 did scientists discover that it glowed.

Blob sculpin (Psychrolutes phrictus)

Deep-sea blob sculpin — The fish looks like a blob at the surface. Ocean Portal / NOAA, Alaska Fisheries Science Center

While the blobfish, once dubbed “the world’s ugliest animal,” has garnered more attention, the closely related blob sculpin deserves time in the spotlight, too. The squishy-looking fish can survive in the dark depths of the Pacific Ocean, between 2,600 and 9,200 feet below the surface. While it was once thought to live from the Bering Sea to waters off the coast of Southern California, researchers in 2008 discovered one off the coast of Mexico. On the seafloor, the animal hunts for crustaceans and mollusks. And like the infamous blobfish, the blob sculpin doesn’t have a swim bladder, as it could implode under the extreme pressure of the deep sea. These fish can get caught in nets that indiscriminately trawl the seafloor for commercially important species. While the animals appear ghoulish and deflated when brought to the surface, they look more like normal fish at the depths they frequent.

Sea pig (genus Scotoplanes)

You’re probably familiar with sea horses, but what about sea pigs? These tube-like, scavenging marine creatures are a type of sea cucumber, but unlike many animals in that group, sea pigs have several legs. The four- to six-inch-long echinoderms can live at depths ranging from 3,300 to 19,500 feet. They feed on decaying plant and animal material on the seafloor and are often found in large gatherings around the sunken carcasses of whales. Researchers have seen hundreds of sea pigs in relatively small areas. Sometimes, young king crabs will ride sea pigs—even hanging on to the echinoderm’s underside. Researchers think this behavior may help the crustaceans evade hungry predators on the seafloor.

Goblin shark (Mitsukurina owstoni)

The goblin shark is reminiscent of a prehistoric dinosaur with its long snout, small eyes and jagged teeth. The shark’s extended snout helps it look for food on the ocean floor. The elongated feature is covered with organs called ampullae of Lorenzini that can detect the weak electrical fields given off by prey. Once the shark detects fish or crustaceans, it can rapidly project its movable jaw forward to snag a meal. Though the maximum size of the species is unknown, scientists who have analyzed photos believe the shark can grow up to 20 feet long. The goblin shark was first described in 1898 off Japan, but the pinkish predator has also been identified off the coasts of Mississippi and California. Rarely seen, the shark lives at a depth of up to 4,000 feet.

Proboscis worm (Parborlasia corrugatus)

The Parborlasia corrugatus species of proboscis worm grows to lengths of roughly six feet or more and scavenges for grub on the seafloor. These worms will eat pretty much anything they come across—including sponges, anemones and jellyfish—and have few predators. Scientists studying the invertebrates have found they harbor toxins, which might make them unpalatable. The worms are found at depths of nearly 13,000 feet and live in South American, sub-Antarctic and Antarctic waters. Though they are often found moving over the seafloor, adults may attach themselves to macroalgae so they can raft to other areas.

Zombie worm (Osedax roseus)

Zombie worms in the genus Osedax eat the bones of dead whales. With no mouth or stomach, the one- to three-inch-long worms survive by secreting an acid from their skin that breaks up the whalebone. Researchers aren’t sure how the animals absorb the food, but they think symbiotic bacteria help with digestion. The holes the animals create in the skeletons of decaying giants don’t just provide food—they also offer protection. Osedax worms were first discovered at a depth of roughly 10,000 feet in 2002 off the coast of California. More than 30 species of the bone-eating worms have since been found, in waters from off New Zealand to the Gulf of Mexico. Interestingly, the larger Osedax worms spotted by the naked eyes of researchers are usually females, as smaller males live inside the female’s mucous tube, biding their time until eggs appear that they can fertilize.

Sea toad (genus Chaunacops)

Sea toads, belonging to the genus Chaunacops, are little-known and “unusually cute” fish with modified fins that allow them to walk along the seafloor. The individual pictured above was found at a depth of about 4,500 feet during the Schmidt Ocean Institute expedition earlier this year. While its bright-red skin looks something like a comfy sweater, a closer look reveals little needles that likely provide protection. Sea toads are a type of anglerfish with a lure on a short stalk between their eyes in order to bring prey closer to that big, frowning mouth.

Sloane’s viperfish (Chauliodus sloani)

At less than a foot long, the Sloane’s viperfish may seem relatively harmless, but its teeth are a force to be reckoned with. The fang-like chompers extend over the upper jaw and much of the way up the viper’s head, allowing the fish to impale its prey—or trap it in its mouth. These deepwater fish have light-producing organs along their bellies that flash blue-green or yellow, simultaneously masking them from would-be predators below and attracting prey. The viperfish also has a glowing lure it can position in front of its mouth to attract unsuspecting prey, which are then rapidly snagged with a bite from the predator’s powerful jaws. While the viperfish may swim at depths of 8,000 feet during the day, at night it often migrates up to depths of 2,000 feet or less to hunt.

Giant isopod (Bathynomus giganteus)

Growing up to 16 inches long, giant isopods in the genus Bathynomus are the largest of the thousands of isopod species on the planet. These giant cousins of terrestrial pill bugs, found in backyards across Europe and North America, may live as deep as 7,000 feet below the ocean’s surface. Giant isopods often scavenge on the carcasses of fish, squid and crustaceans, and they may even accidentally cannibalize their own kind. The creepy creatures crawl along the deep seafloor using their 14 legs and can swim using their fan-like tail and the fluttering pleopods, or swimmerets, found on their stomach.

Frilled shark (Chlamydoselachus anguineus)

This eel-like shark species gets its name from its frilly looking gills, captured in this rare footage in 2007. The eerie predator uses its approximately 300 teeth to capture squid and fish in the deep. Frilled sharks grow to more than six feet in length and swim as deep as 4,000 feet below the surface. They live around the world and have been found from waters off Norway to New Zealand. While not a lot is known about the animals, one amazing fact stands out: After the sharks mate, impregnated females may carry their young for three and a half years.