The ocean is a fascinating environment. It contains a mix of strange and scary marine creatures that look unusual or have peculiar habits and behaviors. In this article, we are exploring 20 ugly fish in the world and what makes them unique.
For instance, the angler fish has features that make it a sea wolf (natural predator). However, these features might be considered ugly by human beauty standards.
Related Read: Fish Facts, Types of Fish.
Quick links to the different ugly fish:
The Goblin shark is one of the ugliest fish in the world. Its peculiar features include a shovel-like snout, retractable mouth, flabby body, and a weakly developed tail. A goblin shark’s mouth can retract underneath its eye or extend forward underneath its long snout.
Another unique feature of the goblin shark is its heavily pored snout. The underside of its snout has a lot of pores. These pores are the external openings of the electricity-detecting organs, ampullae of Lorezini.
They use electricity to hunt for prey in their preferred habitats near the ocean floor at a depth of 3600 feet. Goblin sharks are in the Indian, Atlantic, and Pacific Oceans.
The red-lipped batfish is next on our list of the ugliest fish in the world. The red-lipped batfish lives at ocean depths of 10 to 249 ft in the Pacific Ocean around the Galapagos islands. You can also find it around the edges of reefs up to 390 feet deep.
Many consider the red-lipped batfish ugly fish because of its bright red lips. Its red lips almost look fluorescent. One might think it is wearing bright lipstick or has just finished eating a bloody meal.
The red-lipped batfish has a light brown body with a gray back and a white stomach. Its snout and horn are brown. Also, it has a dark brown stripe that starts from its head to its tail.
Sea pigs don’t refer to pigs that live under the ocean but instead refers to a sea cucumber. It grows up to 6 inches long and weighs almost half a pound. It has a pair of tentacles on its head to navigate the environment and search for food on the muddy ocean floor.
The sea pig feeds on algae, bacteria, and other tiny organisms. It breathes from its anus because it doesn’t have respiratory organs. Its lack of a respiratory system allows it to survive at optimal depths.
The white margin stargazer is a peculiar fish with a black dorsal fin, black spots on the body, and white margins on its second dorsal, anal, caudal, and pectoral fins. They also have poisonous double-grooved spines behind the operculum and pectoral fins.
The white stargazer has its eyes on top of its head with its mouth facing upwards. Their body structure makes them excellent ambush predators; they bury themselves in the sand and lie in an ambush to capture prey. They also have a tongue-like organ that moves around to lure prey.
The blobfish won the world’s ugliest fish contest organized by the Ugly Animal Preservation Society in 2013. It has a gelatinous appearance that inhabits the waters of Australia and New Zealand. Blobfish have soft bones, lack muscles, and a swim bladder.
The absence of a swim bladder helps them survive in the deepest parts of the ocean. Observing the blobfish alive is difficult because you can only find them 2,000 to 3,900 feet deep in the ocean. They can’t survive outside these depths because they die at the sea-level air pressure.
Anglerfish is a deep sea fish with over 200 species. They are a fish species of ambush predators with enormous mouths and stomachs3. Deep sea anglerfish also have long, sharp teeth that help them capture and swallow their prey.
They attract their prey using their unique light-producing organs. This organ is the first ray of the dorsal fin modified into a filament called illicium. It has a sac attached tip filled with a sack of light-producing bacteria called an esca.
The lure organ varies in each species. Some anglerfish species have simple lures, while others have multiple or elaborate lures. Anglerfish can grow up to 4 ft long and live as deep as 8,200 ft in the Antarctic and Atlantic oceans.
Monkfish is one of the ugly fish in the world. It has mottled skin with colors ranging from dark brown to olive green. They have tadpole-like bodies, with a broad head and large mouth. You’ll find this ugly fish in the northwest Atlantic Ocean, from the Grand Banks to the Northern Gulf of St. Lawrence, North Carolina.
Female monkfish grow more than their male counterparts in adulthood. The females grow over 4½ ft long, while males grow up to 3 ft long. Also, female monkfish live longer than male monkfish. Female monkfish live up to 13 years, while the males live up to 7 years.
The Atlantic wolffish is an aggressive predator inhabiting the North Atlantic Ocean. They have long, tapered bodies, a large, rounded head, and a slender tail. They have multiple rows of sharp teeth and a series of dark vertical patches across their body length.
The solitary fish species have blueish-gray bodies, with their underside/belly in a lighter shade than other body parts. They feed on sea urchins, green crabs, sea clams, starfish, and other small fish.
The Atlantic wolffish can weigh up to 50 pounds and grow up to 6 feet long. They prefer to live on hard and rocky areas of the ocean floor. The deep sea dweller can survive in cold waters as low as 35F because their bodies produce a natural antifreeze.
Next on our list of ugliest fish in the world is the stonefish. The stone fish is famous for its camouflage skill. They have an extraordinary camouflage, helping them blend in with reefs or rocks in their habitats.
They can lay in ambush for hours, waiting for a passing prey. Once the unsuspecting prey gets close, they move quickly to swallow prey. Their enormous mouths and powerful jaws allow them to consume any prey whole.
Stonefish also have venomous spines. They use venom from the dorsal fin spine to protect themselves against predators. The sting from the venom is painful and can cause cardiac arrest, paralysis, and convulsions. You can observe these unusual fish in the tropical Indian and Pacific oceans.
There are over 120 species of pufferfish in temperate and tropical waters worldwide. They are well-known for their ability to inflate their body size to scare off their predators. Their body features also vary by species. Pufferfish can be as small as an inch and as long as 20 inches.
They can have various colors, sizes, and skin texture, but some common attributes to all species. They have an inflatable air sack and four teeth fused to form a beak. Pufferfish are incredibly toxic.
They contain tetrodotoxin, a poisonous substance that makes them taste terrible and deadly. The toxin came from the bacteria present in their diet. They are an exotic delicacy in Japan, but only licensed chefs can prepare them.
Frogfish are ugly fish related to angler fish swimming in tropical and subtropical waters. They are colorful and have unique textures that mimic sponges, reefs, and rocks. Their colors include black, orange, red, yellow, brown, and pink.
There are 50 species of frogfish, and they are all terrible swimmers due to the lack of swim bladders. But they can still do it across short distances. However, they mostly use their leg-like fins to walk and hop across the ocean floor.
They can open their mouth up to 12 times its original size, allowing them to swallow prey of any length and size. They also have a modified dorsal fin called an illicium. It is a lure for attracting prey as they lay in ambush.
The sunfish is next on the list of ugliest fish in the world. The sunfish is a large and flat, silver-gray fish with huge eyes. They are one of the world’s heaviest bony fish, weighing up to 2,205 pounds.
People often mistake them for sharks because they swim close to the surface. You’ll find this unusual fish in the open ocean around the world. They feed on small fish and crustaceans. Female sunfish can produce up to 300 million eggs at a time.
The frilled shark is one of the most ancient species in the marine ecosystem1. The deep sea fish resemble eels and grow up to 7 ft. The frilled shark has a slender body, six pairs of gills, a flattened snake-like head, a large terminal mouth, and three-pronged sharp teeth.
Its upper and lower jaws can open wide. Its body color ranges from dark chocolate-brown, brownish grey, or brownish-black. You’ll find it in the Atlantic and Pacific oceans.
Hagfish is one of the ugliest fish in the North Pacific Ocean. The bottom-dwelling fish resemble eels, with the female hagfish bigger than its male counterpart. An adult female hagfish has an average length of 25 inches and weighs 9 ounces, while a male’s length is 19 inches and weighs 6 ounces.
Hagfish are blind and jawless, slimy fish. They produce a clear, thick gel that looks like egg white. However, it is more substantial and congruous. They have special glands that produce protein molecules that react with water and expand in volume2.
They also produce threads from gland thread cells. The threads unravel when they enter seawater, and the gland mucus cells produce mucus, mixing with the pre-slime to form thick mucus. They are also the only vertebrates with a skull but no spinal column.
The spotted handfish is an endangered species. They are a small relative of the angler fish found only in the Derwent Estuary, Tasmania. These sea creatures do not swim. They crawl with their pectoral and pelvic fins that look like hands.
The spotted handfish grows to a maximum length of 4.7 inches. They have either spots or stripes on their brown, cream, or white bodies. The fish diet contains crustaceans, polychaete worms, and tiny shells.
Viperfish have slender bodies with a maximum length of 13.8 inches. The natural predators have long fang teeth that can’t fit into their mouths. They curve close to the fish’s eyes. The deep sea fish come in iridescent blue, green, black, or silver. There isn’t a lot of research on them because they can barely survive outside the deep waters of the Atlantic and Pacific oceans
Toadfish are among the many fish species with unusual appearances. The fish has a soft or whitish color with brown spots. It has small gills in front of the pectoral fin bases. Its teeth are fused, forming a beak-like structure. They always bury themselves in the sand; only their eyes are visible. Moreover, they are toxic to humans.
The vampire fish, also known as candiru, are native to the upper Amazon River and Orinoco River basins in northern South America. They live in shallow, slow-moving, and acidic water with muddy bottoms.
Vampire fish are small catfish without scales. They have transparent bodies that gain color after they feed. Vampire fish have a maximum length of 6.7 inches. Their body is narrow and cylindrical, accompanied by a flattened head.
Blob sculpin is a fish that dwells in the northeastern Pacific deep waters. It is not as hideous as the blobfish but has a similar gelatinous appearance. The blob sculping grows up to 28 inches long and has a huge head, widely separated large eyes, and a curved mouth. It feeds on sea urchins, sea pens, gastropod mollusks, and crustaceans.
Our last ugly fish is the barreleye fish, a deep-sea dweller with strange eyes. Its eyes are bright green and visible through the transparent dome on its forehead. The unique eyes also point upwards, enabling it to view prey above it. The barreleye fish can grow up to 6 inches long.
There are many other fish species considered ugly across the world. They include the telescope fish, sea devils, and payara fish. Although they have ugly features only a mother would love, they still play a crucial role in the marine ecosystem.
Do not let their ugly features scare you away. Instead, appreciate the uniqueness of marine life.
1 | Shark Research Institute. (n.d.). Frilled Shark - Chlamydoselachus Anguineus |
2 | Alaska Department of Fish and Game. (n.d.). Hagfish. |
3 | MBARI. (2023). Â Deep-sea Anglerfish. |
Jen’s a passionate environmentalist and sustainability expert. With a science degree from Babcock University Jen loves applying her research skills to craft editorial that connects with our global changemaker and readership audiences centered around topics including zero waste, sustainability, climate change, and biodiversity.
Elsewhere Jen’s interests include the role that future technology and data have in helping us solve some of the planet’s biggest challenges.
Fact Checked By:
Isabela Sedano, BEng.