Introduction: A Wonderful, Underwater World
It is thought that around 71% of the Earth’s surface is water. Of all the water there is on Earth, a whopping 96.5% of that water is made up by the ocean.
There is a lot of contestation about the actual figures, but it is thought that there is still well over 80% of the ocean that remains unexplored. Yes, you read that correctly. A whole 80% (perhaps more) of the ocean is a complete mystery.
Every time a new patch of ocean is explored there is the question of ‘what will we find?. A lot of discoveries made are of weird and wonderful creatures.
In recent history, there seem to be new creatures being discovered daily. Factor in the notion that only a small percentage of the Earth’s oceans have been explored, and you begin to wonder what else lies out there.
How many more weird and wonderful creatures could there possibly be living out there? when it comes to weird and wonderful sea creatures, we already have our fair share. There are some things living in those oceans that are the fuel of nightmares. Other sea creatures look like something from wonderland.
One thing is for sure, and that is the fact that each and every one of them is bizarre beyond words, with many fascinating facts to go along with them.
In this article, we wanted to share with you some of the most weird and wonderful creatures in the ocean that we could find. In all, we have twenty of them that we want to talk about, each with an interesting fact sheet so you can learn all about them.
How Many Species of Ocean Animals Are There?
The ocean, as we know by now, is vast. This makes it very difficult to know for sure how many species are in there. It is estimated that there are around 1 million different species in total, and around 91% of these are yet to be identified! It is thought that the majority of these species are invertebrates (animals without spines) like jellyfish and shrimp.
These make up a whole 95% of the ocean life population. Many scientists think that ocean life is actually declining due to several different factors such as the speed at which our planet's atmosphere is changing.
This means that ecosystems and habitats are getting destroyed. As a result, species can’t populate fast enough to keep up with the changes and are, instead, dying out.
That being said, over a million species is still a number that can barely be comprehended. It is for that reason that it may be a little easier to group these different species together into types. Check out the table below for some more insight into these million species:
Coral and Invertebrates
Giant clam, Portuguese man o’war, sea urchins, anemone, lobe coral, starfish, and different types of sponge.
Clownfish, John Dory, cod, eel, tuna, Pygmy seahorse, swordfish, ocean sunfish, barracuda, red snapper, and anglerfish
Harp seal, marine otter, beluga whale, narwhal, dolphin, walrus, sea lion, manatee, orca, blue whale, polar bear, and sperm whale.
Turtles and Reptiles
Olive sea snake, hawksbill turtle, green turtle, saltwater crocodile, marine iguana, loggerhead turtle, and banded sea krait.
Rays and Sharks
Goblin shark, giant devil ray, Great White shark, cownose ray, giant Manta ray, spiny dogfish, whale shark, tasseled wobbegong, and blue-spotted ribbontail ray
Cephalopods, Crustaceans, and Shellfish
Dumbo octopus, common limpet, red king crab, giant octopus, tiger prawn, white shrimp, decorator crab, colorful hermit crab, krill, American lobster, and colossal squid.
Viewing them in different groups like this makes it easier to understand, as well as helping you to visualize the different types of sea creatures out there. We are sure you are familiar with many of these but may be less so with some others.
What we are certain of though is that you will not be familiar with all of the creatures we are about to show you, because we have handpicked some of the most obscure, weird, and wonderful creatures in the ocean that look like they could have come from the depths of our dreams (or nightmares…) rather than the ocean.
Keep on reading to be fascinated, awe-inspired, and horrified all at once…
20 Weird and Wonderful Sea Creatures Ever Seen
1. Peacock Mantis Shrimp
The first sea creature to feature on our list is the colorful Peacock Mantis Shrimp.
This shrimp is known for its ability to pack a punch.
It is the heavyweight champion of the oceanic world, which is particularly impressive when considering its delicate looking frame.
They actually punch their prey and other Peacock Mantis Shrimps with their front appendages. They also use them to break open the shells of other shellfish to eat.
They are actually not a shrimp at all, but a carnivorous crustacean. Their front appendages resemble that of a mantis, hence the name. They are commonly found to be any size from 1.2 inches to 7.1 inches.
However, they can also be found at around 12 inches at their biggest. The largest on record was 15 inches! For a crustacean that is that vicious, we think those sizes are pretty impressive! Small but mighty, right?
They can be found in shallow tropical or subtropical waters, mostly in the Indian Ocean or the Pacific. They feast on smaller crustaceans such as mollusks and crabs, sneaking up on them with that heavyweight punch we have already discussed. It is thought that their punch can reach up to 170 MPH, making them the fastest organism on the earth.
2. Pink See-Through Fantasia
The pink see-through fantasia is bizarrely a type of sea cucumber. It is found in the deep sea, in many different places around the world. It is one of the more recent discoveries on our list as it was found back in 2018.
They tend to stay in the water columns rather than on the surface of the sea floor. They are deep sea creatures at the lowest depth possible but they can travel up to 3300 feet for purposes of feeding.
They measure between 4.3 inches to 9.8 inches in total, with the smaller end of the scale being more brightly colored pink.
They are very distinctive creatures and as of yet, not much is known about them.
These mysterious sea cucumbers feed by using their tentacles to push food into their mouths. The food they eat is usually ‘benthic sediment’ found on the seafloor.
This is made of the organisms, along with dirt and debris in the benthic surface of water. They feed for a very short amount of time and seem to only stay on the seafloor for around one minute.
This seems to be ample enough time to feed adequately though. The benthic level is around 13,000 feet under the sea, making these lower sea dwellers quite a difficult creature to spot.
3. Christmas Tree Worm
These festive fellas are a type of marine worm that resides on coral reefs all over the world. That being said, they are most common in the Indo-Pacific ocean as well as in the Caribbean.
These little worms are called so because of their appearance. They literally look like tiny little Christmas trees, in all different colors. However, their true names are Spirobranchus giganteus.
Their bodies are tube shaped and they have appendages on them that act as their breathing system as well as catching their snacks.
They are very small, measuring only around 1.5 inches in length.
They do not move very much as they are sedentary. It is thought that when they find a place they like they stay there, burrowing down into the coral to hide from predators.
Their diet consists of phytoplankton or other microscopic plants that can be found floating freely in the water. Because they inhabit coral reefs, they are often seen and photographed by divers because of their unique eye catching appearance.
The nudibranch is an animal also known by its other, far less glamorous name. These little guys are what may also be known as sea slugs.
However, they are a million miles away from the slugs up here on dry land!
They are a type of invertebrate, and they are a group with, what is thought to be, around 2000 different species altogether!
They have funky, psychedelic colors and some cool facts to match.
Most members of the nudibranch family are hermaphrodites, meaning they have male and female organs in them.
They can be found in oceans all over the world but it is most common to find them in shallow, tropical waters (which makes sense when you consider the fact that they look like tropical flower print shirts!).They range in size from 0.25 inches up to 12 inches, meaning there is a huge variety of them to be seen. They are mollusks, without the shells of course, and they feed on a variety of meals ranging from coral and anemones to algae and sponges.
They have even been known to feed on other nudibranchs. They are immune to the poisons of their prey, and can even retain the poisons of the organisms they eat to use against other prey and predators.
5. Marrus Orthocanna
This weird and wonderful creature resembles a rocket, but it is actually a deep sea creature from the Arctic. More specifically, it is a type of jellyfish. The ‘swimming end’ of the jellyfish is roughly around 3.9 inches in length.
However, the colony length can exceed 6 feet! It has been observed at depths of around 660 and 2620 feet, with the most it has been recorded at being 6600 feet.
It is very hard to see as the depths in which they live mean that next to nothing in terms of natural light reaches them. Because of this, not much in the way of studies have been done on them.
It is thought that their diet may consist of krill, decapods, and other crustaceans. They catch them in their colony spreading their tentacles to ensnare their prey.
These tentacles are often thought of as being similar to fishing lines used by humans.
They are quite a mysterious creature, although photographs of them taken from submersible crafts have shown that, due to their orange color and smoke-like tentacles, they resemble a rocket in flight.
6. Giant Squid
The giant squid dwells deep in the ocean. The name giant is true to form as they can grow up to 33 feet! The female squids can grow even bigger, up to 39 feet.
Definitely some nightmare fuel right there. It is thought that their eyes are around the size of a volleyball. Because of where they live in the ocean they are notoriously hard to study.
There have only been a very small number of people who have managed to get footage of a live squid in its natural habitat.
They remain very mysterious and most of what is known about them are thanks to the dead carcasses of the giant squid floating up to the water’s surface and caught by fishermen in trawlers.
As they live in the deep sea, they span a very large amount of depth. Although scientists have never been able to find out for sure, it is thought that they reside from around 980 feet under the sea to a whopping 3280 feet.
No wonder they are so difficult to study! This has meant that they have adapted over time to be able to live at these dark depths. Their eyes are the largest in the animal kingdom, enabling them to see their prey with ease in the dark waters.
Their prey is thought to consist of other deep sea dwelling fish and even other giant squids! Their main predator is assumed to be the sperm whale, due to beached sperm whales being found with scars that resemble the suckers from a giant squid.
7. Red-lipped Batfish
This weird little fish is found off the coast of the Galapagos islands. They are, for this reason, also known as the Galapagos Batfish.
They get their name from the fact that their mouths are surrounded by what looks like red lipstick.
Their shape makes them look like an animal in flight, hence the reference to the bat. It is for this reason that they are not the strongest swimmers in the ocean. In fact, they are known to scurry quite clumsily along the bottom of the ocean.
They have an illicium, which is commonly found on anglerfish, to attract and lure prey. Their prey tends to consist of other small fish (smaller than them), as well as crustaceans.
They are covered in what looks like thorns, which act as a deterrent for any possible predators.
They grow to just over 9 inches in total. In terms of their dwellings, they can be found at around 10 feet to 249 feet under the ocean.
Due to the scurrying motion that they do, as already discussed, you would be forgiven for thinking that they are some kind of crab. However, those are not legs or claws that help them scurry, but anal, pectoral, and pelvic fins.
8. Bioluminescent Octopus
This impressive feat of nature is also known as the Glowing Sucker Octopus, because, you guessed it, it glows. They are found off the coast of the United States, as well as in the sea around the British Isles at extreme depths.
It is thought that they dwell in depths of around 4900 feet and 8200 feet. For this reason, as with most creatures that live in depths such as these, very little is known about them.
Not many studies have been undertaken on the species and so it is difficult to ascertain much information about them. Their mantle (this is their ‘body’) is thought to be around 2-4 inches long, but their arms (or tentacles) range up to around 14 inches.
That being said, their tentacles are thought to all be of unequal lengths.
Not much is known about its feeding habits, but it is thought that they evolved to become bioluminescent as a means of scaring off possible predators. Their shape makes them look a little like an umbrella, and the bioluminescent features are around the ends of the tentacles. They are certainly an impressive species that we hope to learn much more about in the near future.
9. Vampire Squid
The Latin name of this species is Vampyroteuthis infernalis which translates roughly to ‘vampire squid from Hell’.
As if that wasn’t enough to terrify you for life, the appearance of the squid itself looks like something from a horror movie. That being said, it is still no less than an awe-inspiring creature.
Just like the octopus we just discussed, this squid has adapted and evolved to become bioluminescent in order to survive in the depths of the sea in which it resides.
The vampire squid dwells at depths of 2000 feet to 3000 feet, with some even believing it could be more than this.
Despite its name and similarities, it is neither a squid nor an octopus but instead has its own grouping.
Living at depths like this, they have had to adapt to survive with very little oxygen and in extreme darkness. This alone makes finding prey hard. However, these squids also have no feeding tentacles, unlike other squids and octopi.
For this reason, they have two filaments covered with fine hairs that allow them to find prey to feed on. In terms of feeding, the prey they capture is not what you may think, given their name.
They have no real taste for blood but instead, eat far smaller organisms such as zooplankton. They do, however, have their own predators, having been found in the stomachs of whales, big deepwater fish, and even sea lions who dive deep.
The coffinfish is a type of sea toad which is a name given to different types of deep sea Anglerfish. It is a relatively recent discovery from the end of the 20th century as the first sighting was in 1997.
It is found in the Benthic area of the sea, which is the name given to the deep, muddy bottom. This means it is thought to be at depths of around 164 feet to 984 feet.
Typically they have been found to reside in the Pacific ocean off the coast of Australia in the continental shelf of water. They grow to around 8 inches to 9 inches in length, and in terms of appearance, they are covered in tiny spiny scales that are barely visible.
Their gills can inflate, like those of a pufferfish as a means of acting as a defense mechanism.
They are a little bit of a mystery to us humans, especially in their younger stages of life. However, what we do know is that their feeding habits involve catching prey such as small invertebrates with small lures that reside above their noses.
This lure catches the prey and the coffinfish eat them straight away. It is called the illicium and is a feature that is common with anglerfish. This illicium can be lowered back into a groove on their face.
11. Leafy Seadragon
This interesting creature belongs to the same family as the seahorse and looks as majestic as you would imagine a dragon to be.
They are often known fondly as ‘leafies’, thanks to the protrusions all over their body that resemble leaves or bits of seaweed.
This seaweed-like appearance acts as a form of camouflage for them, allowing them to blend in and hide from their predators. They are well loved in Australia and even feature as the emblem for Southern Australia.
This is because they are only found in the Southern seas of Australia, and can be seen by scuba divers due to them residing at depths of 160 feet. They are typically found in sand patches and amongst the kelp, perhaps because of their ability to blend in well.
This is needed when considering the risks they are subject to from natural and manmade sources. They are sometimes, cruelly, sourced for alternative medicine by humans, as well as being endangered by pollution.
They grow to around 8 or 9 inches, making them a little bigger than their seahorse relatives. However, some scientists have even reported them growing up to 13 inches or more!
They are very independent creatures from the moment they are born and are usually ready to breed at around two years old. They feed on a diet of plankton, fish in their larval stage, amphipods, and small shrimp.
They do this by sucking them up through their snout. Unlike their seahorse relatives, they can not curl their tails around seaweed, kelp, and seagrass to stay safe during a storm. For this reason, they are often found washed up on the shores if the weather has been particularly bad.
The blobfish has found much fame due to it being called the ugliest animal to exist. However, we think it has unfairly got this title, especially since this list alone has provided it with some worthy contenders.
Some people may find it the complete opposite of ugly, and think that it is cute! It is typically found off the coast of Australia and some of the surrounding areas such as New Zealand and Tasmania.
It’s strange ‘blobby’ appearance is thanks to the fact that its body is a gelatinous mass, made so to help them live in the extreme depths of 2000 feet to 3000 feet underwater.
Their body allows them to float and easily catch the food that floats towards them. This is usually made up of crustaceans and other edible matter.
They are thought to be completely still for most of their lives. This is because they are almost entirely free of muscles. Certainly, they can barely support their own weight when brought out of water. It is not thought that they have many predators, but they do often get accidentally caught in the nets of sea trawlers.
13. Yeti Crab
The yeti crab is called so because it looks as though it is covered in fur that resembles the mythical animal/ creature known as the yeti. They have only been known to us since 2005, although do not mistake this for being because they are rare.
Quite the opposite in fact, since they are very common. The reason that they were not found until relatively recently is perhaps due more to the fact that they reside in some of the most extreme conditions in existence.
They live in hydrothermal vents in the relatively small area between freezing water and 700-degree Fahrenheit water.
If they move too close to the hot water, they will boil to death. Further into the cold and they will freeze.
They are typically found in depths of around 2200 feet under the sea. They have to live in these very specific conditions but this has not slowed them down. Photos have been seen of hundreds of them gathering together in these areas.
In terms of appearance, these crabs have no eyes. They do, however, have distinctive hairy claws and measure just under 6 inches in length. The hair on their bodies attracts bacteria which is their main source of food. It is thought that they ‘farm’ the food themselves in this way.
Jawfish are tiny little fish that live in warmer areas of the Atlantic, Indian and Pacific oceans. They measure around 1.9 inches.
However, there is one member of the species, the giant jawfish, which can reach up to one foot 8 inches.
The jawfish live in depths of around a few hundred meters, meaning they reside in relatively shallow waters compared to some other sea creatures on our list.
They burrow into the sand tail first and tend to live there. They are a type of fish known as mouthbrooders.
This means that they hatch their eggs in their mouths, where they can be protected from predators.They are then emitted from the mouth of the fish around 10 days later.
They tend to live off planktonic matter and smaller shrimp and brine that will fit into their mouths. There are around 80 species of jawfish in total, all of which are of different colors, shapes, and sizes, residing in slightly different places around the world.
15. Whitemargin Stargazer
This marine fish gets its name from the fact that its eyes are on the top of its head as though it was stargazing. They burrow into the sand, burying themselves almost completely with just the top of their head showing.
This hides them from predators whilst still allowing them to see. However, this camouflage technique is not merely a means of hiding them from predators, but also a way of sneaking up on their prey.
They wait for prey, and when it approaches them, they pounce. Prey are attracted to them because of their oral lure which looks like a worm or other food for their prey.
They have the ability to deliver both venom and electric shock to their prey to catch it. They particularly like eating smaller fish.
It inhabits reef flats but because of the nature of the fish and the fact it likes to camouflage, they are very rarely seen. They are thought to be able to reach lengths of around 17 to 18 inches, but some can be much smaller than this. In some places around the world, stargazer fish are sold in fish markets as a delicacy as the poison cannot harm humans once eaten.
16. Arctic Hydromedusa
The Arctic Hydromedusa is a mysterious creature that resides in the depths of the sea. They can generally be found right through the ocean from the surface to the very bottom.
They are minuscule creatures that typically go unnoticed by us humans as they can easily slip through the holes of fishing nets.
As well as this they are transparent either completely or mostly opaque.
Not much is known about them, but they are thought to be a part of the cnidaria family.
They are similar to jellyfish in appearance as they have a jelly-like substance in their bodies.
They tend to prey on organisms such as plankton as well as different organic matter floating in the depths of the ocean and bacteria. As they are related to the jellyfish they are very similar in appearance, albeit far smaller.
17. Obese Dragonfish
The obese dragonfish belongs to the group known as the ‘barbeled dragonfish’. They are called so because of their very long barbel which resides on their head, under their chin to be more specific.
This barbel serves as a way of producing light. This makes the obese dragonfish a member of the bioluminescent fish family. They live at depths of 5000 feet making them a deep water dweller.
Typically they are found in the seas around Australia, namely the Indian, Pacific, and Atlantic.
As well as the light producing barbel they also have photophores all over their body in different places as a way of producing more light.
The barbel and other lights allow them to attract prey and potential mates. In terms of prey, however, not much is known about what their prey consists of. They are thought to be carnivorous animals though, with super sharp teeth to show for it. They are thought to grow to around 55 centimeters in tidal, which is around 21 inches.
18. Red-Spotted Blenny
The blenny is a common fish found in coral reefs in the Indian and Pacific Oceans. The red-spotted blenny belongs to the family known as combtooth blennies.
The red-spotted blenny is called so because of its distinctive red spots that cover its body.
They are thought to reside relatively close to shore, in reefs around 20 feet underwater. They tend to grow to around just under 6 inches in total, making them a relatively small fish.
There is not a huge amount known about this distinctive little fish individually, but what we do know is that they may share characteristics with the wider combtooth blenny family.
They tend to eat small creatures from the Benthic regions of the ocean such as crustaceans, shellfish, mollusks, and even algae and plankton. Some blennies can even venture out of the water thanks to their pectoral fins that act similarly to feet.
19. Black Swallower
This deep sea dwelling fish has a reputation for biting off more than it can chew… Ok, perhaps that is not quite true.
However what it does do is swallow, with much ease, fish that are much bigger than it!
It certainly has earned that name, then! It can be found all over the globe in tropic and subtropic waters.
When we say they are deep sea fish we really mean it as they can live in depths up to 9000 feet under.
They are very widely found and are the most commonly found fish of its genus in the North Atlantic ocean.
They swallow their prey whole, preferring bony fish. There have been instances where a washed up black swallower has been found to have fish almost four times bigger than it in its stomach.
They tend to grow to around 7 to 8 inches long, with the largest length known currently being 9.8 inches. This is impressive when considering they can swallow fish that are 34 inches! In terms of appearance, there is nothing particularly distinctive about it.
It is rather plain in color. What makes it so weird and wonderful is the amount that they can swallow. Their lower jaw is bigger than the upper part of the jaw to help them swallow these bigger animals.
They also have the added bonus of very sharp canine like teeth at the front. Their teeth fit together neatly, interlocking when the jaw is closed. This traps their prey, allowing them to swallow it.
20. Napoleon Wrasse
The Napoleon Wrasse, also known as the humphead wrasse, is perhaps a little better known than some of the other fish and creatures that feature on this list.
This is because of its status as an endangered fish.
It is a luxury edible fish that is in danger of becoming extinct thanks to overfishing in southern Asia.
It is typically found in the Indo-Pacific ocean region, surrounding many of the small Pacific and Indian islands.
However, they can also be found around the east coast of Africa and in the Red sea. It is a very large fish, growing to around 6 feet in length, and dwells in coral reefs.
It has a prominent bulge on its forehead, this bulge is said to resemble the hat that Napoleon wore, hence the name.
Whilst they do frequent coral reefs, it is more common to see the younger Napoleon Wrasse fish in the sandy parts of coral, whereas the adults tend to prefer deeper coral reefs and lagoons.
They tend to prey on hard shelled animals such as mollusks and crustaceans. They are also fond of starfish.
Conclusion: Will You Ever See These Animals?
That concludes our list of 20 of the Most Weirdest and Wonderful Creatures in the Ocean. We are sure by now that you may all be wondering whether you will be able to see these magnificent creatures for yourself. Certainly, many of them can be seen, either in captivity in zoos and aquariums, or by going scuba diving.
These include any of our coral reef dwelling weird fish and wonderful creatures such as the leafy sea dragon. Other fish, particularly the fish that dwell very deep under the sea will be very difficult to see for yourself.
Some of them, for example, the Marrus Orthocanna, have rarely been seen by scientists let alone you and I. However, one thing is for certain and that is because of the constant advances in technology and scientific exploration, new ways of researching the ocean’s magnificent creatures are being found daily.
We are sure this list will be able to be expanded on yearly with the number of new discoveries being made. However, for now, we are sure you are elated with our list of 20 of the weirdest and most wonderful we could find!