The ocean's depths are as vast as the planet and as unknown as space. While biological discoveries continue to progress, some parts of the ocean are so inaccessible that, despite the human race's best efforts, only a sliver of the truth has been uncovered.

Here are eight of the deep-sea creatures found in the area surrounding the Mariana Islands, near Japan's remote islands.

1. Dumbo Octopus (Grimpoteuthis)

Deep-Sea Creatures that Dwell North of Mariana Trench
Dumbo Octopus Photo: NOAA Okeanos Explorer / Wikimedia Commons

The Dumbo Octopus, named after the Disney character, has flappy ears, deep-set eyes, and eight tiny tentacles. It can be found at least 9,800 meters beneath the sea in the Mariana trench.

The dumbo octopus, which measures 8-12 inches, is a predator that can swallow its prey whole in one gulp.

2. Comb Jellies (Ctenophora)

Comb Jellies
Photo by Jonathan Diemel on Unsplash

Comb Jellies are gelatinous creatures with luminous body structures that diffract any light that falls upon them. They move around in the water using their comb-like plates.

While they are visually captivating, these underwater marvels are voracious predators who have been known to attack their own kind. Some are as small as a few millimeters long, while others are nearly 5 feet long.

3. Benthocodon (Benthocodon hyalinus)

The Benthocodon is an opaque organism, whereas most jellyfish are transparent. The bell, a red-colored cover that covers the lumination of the organisms consumed by the Benthocodon, keeps it hidden from predators. It floats through the ocean with around 1,500 tentacles.

4. Deep-Sea Hatchet Fish (Argyropelecus Gigas)

The deep water hatchet fish is a small species with a grim appearance, ranging in size from 2.8 cm to 12 cm. The Hatchetfish has evolved an innovative camouflage mechanism, despite its small size, making it easy prey.

These fish, like most other deep-sea creatures, can produce light from their stomachs, making them bioluminescent. The Hatchet fish can adjust its light to match the light in the water, effectively keeping it undetectable to predators.

5. Barreleye Fish (Opisthoproctidae)

The translucent head of the Barreleye fish shows its whole guts, which are filled with fluid. When the fish preys on jellyfish, this membrane protects it from stings.

Its flat fins let it remain still and move with pinpoint accuracy through the dark oceans. The interesting monster has been caught in fishing nets despite lurking in the incredible depths of the ocean.

6. Black Seadevil/ Seadevil Angler Fish (Melanocetus)

Angler Fish
Photo by NOAA on Unsplash

The Black seadevil, a scary creature in movies, is just as terrifying in real life. This angler fish is known for its luminous antenna-like muscle protruding from its head, sharp teeth, gaping mouth, and eyes exploding out of their sockets.

This light draws its prey into proximity, making it easy to catch. The male of the black seadevil reproduces by fusing with the female and living off her resources until it can produce sperm.

7. Ping Pong Tree Sponge (Chondrocladia)

The thin, stalk-like creature gets its name from its appearance, which resembles a tree producing ping pongs. Small hook-like extensions adorn these "ping pongs." Any prey that comes into contact with it is trapped and slowly devoured by the sponge.

8. Frilled Shark (Chlamydoselachus anguineus)

The name of the Frilled Shark can be attributed to its frilled gills, of which it has 6 or 7, as compared to the usual 5. With a slender snake-like body, the shark looks more like an eel. Apart from its entire physique, the eeriest feature of this shark is its set of 300 teeth.

Even though this shark lives at least 5000 meters below the surface, it was one of the first deep-sea creatures to be discovered in the 19th century.