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The Coolest Underwater Animals: The 15 Most Unusual Sea Creatures

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This deep sea fish lives anywhere from 600 to 4000 meters underwater off the coast of Australia, just floating above the sea floor. The Blobfish lacks definitive muscle which enables it to have a smaller density than water and swallow floating crustaceans. This creature was deemed the worlds ugliest animal with its large globular mass and seemingly unhappy expression. When in actuality, the Blobfish resembles your typical fish deep underwater. In order to survive in those depths and extreme pressure, the Blobfish does without the swim bladder, allowing its stomach to remain intact.


Christmas Tree Worm

These worms contain two brightly colored spiraled shapes, from which they derive their name. These spirals are the worms respiratory systems. The worm is unable to move outside its tube; however, small appendages aid the worms mobility. These creatures are seen throughout the worlds tropical oceans, embedded in large masses of corals. A marvel to divers and photographers alike, their crowns have many agape and therefore are deemed one of the most unusual sea creatures.



The Viperfish is most known for it's large predatory teeth and hinged lower jaws. Their fangs are so large they would not fit in their mouth unless they wrap up towards the fish's eyes. This species contain a photophore which aid in capturing prey and communicating to other fish of the same species. By flickering the light on and off on the back of their dorsal fin, smaller fish will swim towards the Viperfish who immobilize the prey with their teeth. Viperfish grow to lengths of one to two feet and live for up to 40 years in the wild. Due to their large stomachs, the Viperfish can go long periods of time without food.

Napoleon Wrasse

Also known as the Humphead Wrasse, this fish can grow to lengths of 6 feet. The Napoleon Wrasse is best known for its large fleshy lips and bulbous head. These fish can be found on near coral reefs, preying on crustaceans, mollusks, smaller fish and echinoderms. While this animal has a long life span of up to 50 years, they are currently threatened due to habitat destruction/loss and overfishing and illegal fishing.


Kiwa Crab

This crab is best known for its blonde setae which resemble fur, giving it the nickname "yeti crab". This creature was discovered in just 2005 by the Monterey Bay Aquarium Research Institute from the RV Atlantis. Thought to be blind due to the lack of pigment in this creatures eye, the crab's pincers are believed to detoxify poisonous minerals in its habitat. The Kiwa Crab lives near hydro thermal vents; and still little remains known in regards to how this creature fits into this ecosystem. This crab is a distant relative to the hermit crab which can be found in tide pools across the world.


Vampire Squid

This creature is a living fossil, meaning it has gone through little change since the time of the dinosaurs. Resembling something from a sci-fi comic, the Vampire Squid surprisingly only reaches lengths of 6 inches to one foot. This animal resides half a mile deep in the ocean and uses its unique blue eyes to see. Using two large fins near its head, the vampire quid is able to propel itself through water quite quickly. In defense, the squid can essentially turn itself inside-out. The creature accomplishes this by moving its arms over its body to form a protective web. The Vampire Squid is also capable of luminescence through the use of photophores located on its body.



Known for its large menacing teeth, the Fangtooth has earned the nickname ogrefish by many, having the largest teeth of any fish in the ocean proportional to its body. These deep sea predators are actually harmless to humans as they hunt squid and smaller fish. These fish can be observed between 600 and 6500 feet deep where temperature can drop drastically and pressure can be quite extreme.

Acantharians Amoeba

This amoeba resembles a star shape, formed from sulfate crystals ten or twenty diametric spine. These creatures are characterized by their skeletons which not not fossilize after death, but instead quickly dissolve. Little is known of these fragile creatures yet their striking shape perplexes many and opens the doors to the amazing ocean creatures inhabiting this planet.


Pelican Eel

The Pelican Eel is best known for its large mouth that is actually bigger than its own body. The hinged jaw can be opened to swallow organisms larger than the eel itself; however, studies show that these creatures mostly consume crustaceans. The eel is able to move through whip-like motions of its long tail. The tail glows pink while flashing colors are suggested to be used to attract prey. This deep sea fish is rarely seen by humans as it resides 500 to 3000 meters underwater.

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Phronima (Amphipod)

This parasite is extremely versatile, able to live not only in many regions of the oceans but also in places other than the sea floor. Thought to be the inspiration for the xenomorph from Alien, this creature is barrel shaped with a semi-transparent mass and large front claws. These creatures can carve away the interiors of their prey, salps, and crawl their way inside, floating the ocean from within. In this barrel shape, the females are able to reproduce and carry their eggs on-the-go.


Bioluminescent Octopus

These sea creatures are of yet another species which may be found in a sci-fi movie. While little is known of this specimen, the octopus is scientifically named Stauroteuthis syrtensis with tentacles averaging 14 inches in length and approximately 60 suckers on each one. The octopus is found in the North Atlantic Ocean at depths of 500-4,000 meters. Bioluminescence comes into play as the octopus shines a blue-green light from its 40 photophores, which is believed to play a role in the octopus's defense mechanisms.


Sea Angel

This small species only reaches lengths of 5 cm with gelatinous semi-transparent body. The Sea Angel has two wing-like appendages, called parapodia, which lends itself to the creatures name. These appendages cause this creature to resemble, of not an angle, a butterfly. Sea Angels also have tentacles that enable them to grasp their prey; as carnivores, this creature usually eats fellow pteropods.



Possibly the cutest sea creature, the Axolotl is also known as the Mexican Walking Fish; which is a misnomer, as the creature is actually an amphibian, not a fish. The Axolotl is endangered and is often caught in captivity and bred to produce a variety of colors. Research is currently being done in this animal because of it's healing powers and regeneration abilities - able to re-grow an entire limb! The Axolotl also has the ability of neoteny, meaning they retain traits from when they were young and also have the ability to reach sexual maturity without undergoing metamorphosis.


Pink See-Through Fantasia

This sea cucumber can be found 2,500 meters below the surface in the Celebes Sea. Little is known of this creature except that they do have webbed swimming structures which allow them to propel themselves further faster.

Glass Squid

This transparent squid can be found throughout the world's oceans, mostly in shallow waters as they are able to remain camouflaged. Their body comprises most of their mass, with only three short arms, two of which contain suckers or hooks. The only structure which can be seen through the body is the squid's digestive gland. These creatures also have the power of bioluminescence like many deep sea creatures which can aid in prey capture.



Sushi worm on October 06, 2020:

Axolotls are one of my favourite animals ! I’ve always wanted one as a pet !

Delilah Kay from United States on May 30, 2019:

Blobfishes are so interesting haha, I love to read about them and I was surprised that you talked about them in this article.

coll; on May 01, 2017:

nice i like all the animals this will help me on my project :) thxs

Ann1Az2 from Orange, Texas on June 02, 2014:

God's creations are truly amazing. These are some I didn't know about, so thanks for introducing me to them. I enjoyed the video and the photos.

FlourishAnyway from USA on May 30, 2014:

What an interesting group of critters. Some are so ugly they're cute.

Marie from Canada on May 30, 2014:

Interesting Hub! I didn't know some of the animals. Axolotls are so adorable. Have you heard of decorator crabs? I think that they are pretty cool.

Beth Perry from Tennesee on May 28, 2014:

How fascinating! I did not know about several of these creatures and loved your eye-opening information. And the little Axolotl is adorable!!

Voting up.

Alyssa S (author) from USA on May 26, 2014:

Thanks, there's definitely a lot we don't know out there. It's pretty cool I'd say.

I.W. McFarlane from Philadelphia on May 26, 2014:

Very interesting hub. Honestly, I didn't know that most of these creatures exist!

Kofantom on May 26, 2014:

nice hub mate, the deep ocean is full of strange and alien-like creatures. You may also want to add the red lipped bat fish. I wrote a hub about it a few hours ago:

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