Ready to meet some of the ocean’s most peculiar residents? The deep blue sea is a treasure trove of mysteries, with creatures so bizarre and incredible that they must be seen to be believed.
From the enigmatic blobfish, dubbed the world’s ugliest animal, to the majestic dragon-like arowana, our planet’s waters hide some truly weird looking fish.
These unusual fish not only challenge our perceptions of aquatic life but also flaunt nature’s flair for the dramatic and the unexpected.
1. The Blobfish
This gelatinous creature has been dubbed the “world’s ugliest animal,” but don’t let its appearance fool you. The blobfish is a master of adaptation, thriving in the extreme pressures of the deep sea.
With a body that resembles a melted blob, this fish lacks a skeletal structure, allowing it to withstand the crushing depths of up to 4,000 feet. Its jelly-like appearance is a result of its low muscle tone, which helps conserve energy in the food-scarce environment it inhabits.
Despite its unappealing looks, the blobfish serves as a reminder that beauty lies in the eye of the beholder, and that nature’s wonders come in all shapes and sizes.
2. The Arowana
Often referred to as the “dragon fish,” the arowana is a true aquatic marvel. Native to the Amazon basin, this freshwater fish is revered for its striking appearance and mythical status.
With its elongated body, large scales, and vibrant colors, the arowana exudes an air of majesty. Its unique ability to breathe air from the surface allows it to survive in oxygen-depleted waters, making it a highly sought-after species in the aquarium trade.
In some cultures, the arowana is believed to bring good luck and prosperity, leading to its popularity as a prized possession among collectors.
3. The Male Jawfish
Prepare to have your perceptions of parental roles shattered. The male jawfish is a true trailblazer in the world of fish reproduction, defying traditional gender norms.
Unlike most fish species, the male jawfish takes on the role of incubating and caring for the eggs after mating. After the female lays the eggs, the male scoops them up into his mouth, where they remain until they hatch.
During this period, the devoted father forgoes eating, focusing solely on providing oxygen and protection to the developing embryos. This remarkable behavior showcases the incredible diversity of parental strategies in the animal kingdom.
4. The Picasso Triggerfish
Named after the renowned artist Pablo Picasso, this vibrant fish is a true masterpiece of nature. With its striking colors and intricate patterns, the Picasso triggerfish is a sight to behold.
Hailing from the Indo-Pacific region, this territorial fish is known for its aggressive behavior, fiercely defending its domain against intruders. Despite its feisty nature, the Picasso triggerfish is a popular choice among aquarium enthusiasts, captivating viewers with its mesmerizing beauty.
Interestingly, these fish are known to sleep on their sides, nestled among rocks or corals, adding to their quirky charm.
5. The French Angelfish
Elegance and grace personified, the French angelfish is a true gem of the ocean. Found in shallow reefs across the Caribbean and the Bahamas, this fish boasts a striking appearance that is sure to leave you spellbound.
As juveniles, they display vertical stripes that fade as they mature, revealing a vibrant yellow hue with hints of blue and black. Their distinctive shape and captivating colors have made them a favorite among divers and snorkelers alike.
Despite their angelic appearance, these fish are known for their territorial nature, fiercely guarding their coral reef homes from potential threats.
6. The Regal Tang
The regal tang gained popularity as a type of fish in the critically acclaimed film Finding Nemo and was portrayed by a cartoonized version named Dory. Their oval shapes have blue-colored bodies and a yellow tail alongside a pectoral fin.
Regal tangs are commonly found in the Indo-Pacific waters and settle around coral reefs along the ocean shores. The primary diet of the regal tang comprises algae, and most times, the fish move around in groups or pairs.
A group of regal tangs may comprise 12 members and can include some other species of tang and surgeonfish. Their coping mechanism against predators is to lie on their side and pretend to be dead until the predator goes away.
7. The Clown Triggerfish
The clown triggerfish is distinct at first glance. Their dark lower body with large white spots and yellow upper body with black dots are distinctive enough to mark this fish species as an unusual fish. They also sport white and yellow stripes on their face.
They may seem a bit relaxed at their early stages, but once they grow into adults, their territorial tendencies begin to manifest. They can exist alongside other fish species, but if the other species are not as aggressive as the clown triggerfish, make sure the triggerfish gets added to the tank last.
You will find the clown triggerfish in the Indo-Pacific ocean, and its broad teeth and strong jaws make it a formidable predator for its prey. It preys on crustaceans and sea urchins.
8. The Juvenile Emperor Angelfish
The unusual thing about the juvenile emperor angelfish is how beautiful it looks, and when placed in an aquarium, it makes a gorgeous sight. This gorgeous creature grows up to a length of 15 inches but when grown in a tank, it grows to a length of 12 inches.
Only experienced fish keepers should keep this fish species because they have special tank and water requirements. There is also a high price tag attached to the fish.
The emperor angelfish live around rockwork and around coral growth in clear lagoons. They are mostly found in the reef areas of the Indian and Pacific Oceans. Male emperor angelfish are highly territorial and with two females, they can dominate a territory as large as ten thousand square feet.
9. The Asian Sheepshead Wrasse
The Asian sheepshead wrasse, also known as the kobudai, is a clear-cut example of reversing the roles. This fish is known to display high levels of hermaphroditism, as a female Asian sheepshead wrasse changes routinely to male at a point in the life of the female kobudai, she can turn to male permanently.
This fish is common in the western Pacific Ocean and can grow up to a length of 100 centimeters. The heaviest recorded weight for this fish species is 14.7 kilograms.
Apart from being a hermaphroditic fish species, the appearance of the Asian sheepshead wrasse is also quite unusual. These fish have thick lower jaws and their bodies are narrow and elliptical with standout bumps all over their heads.
10. The Coffin Fish
The coffin fish is common in the southwestern Pacific waters off the Australian east coast. It is categorized as a sea toad species and dwells in salty temperate waters at a depth of between 50 to 300 meters.
The coffin fish has a spiny and globose body that can grow up to a 22-centimeter length. It comes with inflatable gills that collect water while serving as a defense mechanism. The water it draws with its gills can supply the coffin fish with oxygen for up to four minutes.
Feeding for the coffin fish involves luring small prey with their snouts.
11. The Scallop
Scallops are present and common in the oceans but never in fresh water. They are used to make delicious meals, especially the white adductor muscle which becomes tender and round after cooking it.
Scallops come with shells shaped like fans with bright colors. These shells are highly valued by shell collectors and are used for designs in art and architecture because scallops are widely distributed, they are one of the most popular items that beachgoers usually collect.
Most scallop species live in waters between the low tide line and 100 meters, while some species can be found in deeper water. Some scallop species are also opportunistic when it comes to their living environments as they are highly adaptable to various conditions.
12. The Lionfish
Lionfish have a reputation in North America for being invasive because they are notorious for killing all native species. Their reproduction is fast, up to 30,000 eggs every week, and they are easily adaptable to new environments.
They are common in the Pacific Ocean and have a length between 2 inches and 16 inches. They come with feathery fins that look attractive to smaller fish and lure them in. Lionfish look harmless with their beautiful zebra-patterned striped bodies, but they have highly venomous spikes that can inflict severe pain to anything that gets too close.
An interesting thing about lionfish is the ability of their stomachs to expand up to 30 times the normal size after feeding. They have large appetites and can reproduce throughout the year.
13. The Tasseled Scorpionfish
This is also known as the scorpionfish and is commonly found in the Indo-Pacific area. It comes in a variety of colors depending on where it is found, and some of its other names include rockfish, stingfish, and small-scale firefish, amongst others.
It has similar behavior to stonefish in the way they capture their prey. A tasseled scorpionfish will often lay in wait for its prey, well hidden and camouflaged. It is also highly venomous, but they will hardly attack anyone, as the venom is mostly for defense from predators.
It is a carnivorous fish that can grow up to a length of 36 centimeters. The unusual thing about the fish is its head region, where there are tassels surrounding its jaw, looking like beards.
14. The White Margin Stargazer
The white margin stargazer has different names such as popeye fish, marbled stargazer, popeyed fish, and tube-nosed stargazer. It earned the name stargazer from the position of its eyes above its head, and the fish has an unusual way of burying itself in the ground, leaving only its eyes and mouth above the sand as it waits for prey.
Stargazers are a different breed of fish that has some electric organs behind their eyes. These electric organs can discharge up to 50 volts of electricity that can send any creature that comes across them into shock.
Stargazers are naturally always laying in ambush for prey, and the combination of their electric shock and venom has earned them a spot on the list of the meanest animals in existence.
15. The Mandarin Fish
The mandarin fish is common in the Pacific Ocean, and its natural habitats are inshore reefs and lagoons. It is a unique species of fish with tiny spikes all over its body. If anybody or anything tries to handle it, the spikes inject toxic mucus into them.
The blue coloring on the mandarin fish is produced by the fish itself, and only two species of animals in the world can produce their own blue coloring. Mandarin fish feed on small invertebrates that live at the bottom of the water.
Mandarin fish itself is mostly found at depths of between 3 to 59 feet, and the fish species move around in small groups. It is a great choice of fish species for an aquarium, but feeding it can be a bit difficult, so it should be left for expert aquarists.
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Davin is a jack-of-all-trades but has professional training and experience in various home and garden subjects. He leans on other experts when needed and edits and fact-checks all articles.