17 Mysterious Sea Creatures Lurking Beneath the Surface

By Alexandru Ion

Mar 20, 2023

Beneath the surface, there's an entire alien world that we are only beginning to plumb.

It’s brimming with oddities both fantastic and horrible, with terrible beauty and elegant savagery that we can only imagine.

Bioluminescent Octopus


The Stauroteuthis syrtensis octopus directs prey into its beaked maw with the efficiency of landing lights on a runway.

Crossota Norvegica Jellyfish


Artistic and stunning with its deep crimson hues, this breed of jellyfish hails from the arctic circle.

Gulper Eel (Pelican Eel)


Found as far as 10,000 feet down, the Gulper uses a lighted tail to lure in unsuspecting prey, it appears to be almost all mouth, with a sac for a stomach that can distend to swallow things that are many times larger than itself.

Goblin Shark


It’s eyes are mostly decorative, since it tends to exist thousands of feet down. To navigate the inky waters, the strange protuberance that sticks out from its face is actually an electro-sensitive “sight” organ.

Frilled Shark


An oddity as rare as it is ancient, the Frilled Shark is prehistoric in every way. Many of its attributes have more in common with ancient species than modern ones.



Built for ramming speed the Viperfish has a special vertebrae on its back to absorb high-velocity impact, due to its reckless hunting method. It tends to rush its victims, impaling them on its protruding fangs, then gnawing them away at its leisure.

Vampire Squid


A nasty carnivore that lives in some of the most inhospitable, low-light and low-oxygen places in the world, it has the distinction of bearing the largest eye to size ratio of any creature alive.



Rather than using its electrical system for bioluminescence, like many of its kin, it instead is able to deliver an electrical shock that immobilizes its meals before swallowing them whole.



A fish that is thought to have once been part of the shark family, the Chimaera is called the Ghost Shark by many, both for its haunting appearance and cartilaginous body, showing a relation to sharks themselves.

Pink Handfish


Evolution in action, the Handfish is a tiny breed that bears a horrifying resemblance to both their other aquatic brethren, and to human beings.

Kiwa, God of Shellfish, Yeti Crab


Though it exists more than 5,000 feet down, the fur it bears is unlikely to help it much with warmth, but may be a sense organ, since the creature bears no eyes.

Pacific Blackdragon


Able to grow up to 2-feet long, you’re likely to only ever see a female, since the 3-inch males die immediately after mating. These girls are coated in black from snout to tail since they are ambush predators who must blend in.

Giant Isopod


A huge, alien, deep-sea scavenger, the Isopod is far more unusual than most creatures invented by myth or science fiction. They spend their existence living on the detritus that adorns the bottom of the sea.



Named for the glowing lure it uses to fish for prey, the Anglerfish is actually far stranger than their odd appearance. They reproduce when males lose the ability to digest and latch onto a female.

Sea Wasp


Bearing the distinction of the most venomous creature on the planet, above or below water, a sting from one of these elegant jellyfish can kill a person inside of 3 minutes.

Pycnogonida Sea Spider


The worst nightmare of any arachnophobe, the Sea Spider is a mixture of true terrestrial spiders, and horseshoe crabs.

Sarcastic Fringehead


These long, slender fish will use anything they find on the bottom of the sea – from snail shells to discarded human garbage – as their home.