Life under the water is unimaginably diverse. Have you ever noticed how different we are from each other? Even though we belong to the same species, we still have so many distinct features. The same is the case with underwater animals. There is a vast variety of fish; some are dangerous while others are friendly aquarium fish. Every fish has distinctive features and amazing adaptations which makes its survival easy. Some of these fish are referred to as river monsters because of their different or rare traits.

The aquatic ecosystem is home to many diverse species of fish. Many movies, TV shows, video games and cartoon movies have been made that feature these river monsters. The famous television show River Monster attempts to explore these monstrous fish. The host of this show is courageous and daring. He travels to various places around the globe in search of these river monsters along with other rare water species. Below is the list of some of these real-life river monsters that might give you the scare of a lifetime.

15. Chui-Chui

It is also known as a ripsaw catfish and it is a species of thorny catfish. It is mostly found in the Orinoco and the surrounding rivers of the Amazon. This fish weighs almost forty pounds and can grow up to three feet in length. The scutes along the back of the Cuiu Cuiu fish give it an armored appearance. They mostly feed on detritus, chironomid, ephemeropteran larvae, and crustaceans; they can also eat prepared food. It is an aquarium fish, but one thing should be kept in mind: the aquarium should be as large as possible because it grows rapidly. This fish is peaceful, light and shy contrary to what one would think of it because of how it looks.

14. Vundu Catfish

The vundu catfish weighs almost 121 pounds and can get up to five feet long. It is mostly found in rivers and fresh water habitats of Sub-Sahara Africa and also in the Nile. This fish likes deep water and during the night, it comes up to feed on fish and small vertebrates. Sports fishermen are attracted to this fish, because of its length; it is long and muscular but not heavy. It can also survive out of water for a long time and its estimated lifespan is twelve years. It is olive-brown on the dorsal side and light brown or off-white on the ventral side. They come close to shore at night, so that is the perfect time to catch them. It is considered to be a strong fish.

13. Nile Perch

The Nile perch is a giant fish, as it weighs almost 500 pounds and it grows approximately six feet in length. It is naturally found in the rivers of the Congo, the Nile, Senegal, Niger and other river basins. It is a large mouthed fish. The Nile perch is greenish brown in color and it is a bit slippery from below. It is largely considered a food and game fish. Because of the change in their ecosystem due to natural reasons, the Nile perch population has declined catastrophically. It can live in any fresh water habitat but mostly prefers warm tropical waters. It usually feeds on insects, crustaceans, mollusks, and fish. They live about sixteen years and their breeding season is from March to June.

12. White Sturgeon

They are considered to be the largest archaic fresh water fish in North America; they reach up to 200 feet in length and weigh almost 1800 pounds. They grow slowly and mature in a period of eight to twenty years, whereas the fish in the South mature faster as compared to the North. They can live in a variety of conditions and are usually classified as bony fish. This fish does not have any scales, it has a small mouth and its head and body are very slender. Their color can either be grey, olive or brown. They do not have any teeth and can sense food with the help of barbells that are present near the mouth. They are inhabitants of deep water and they are considered to be nocturnal fish.

11. Arapaima

They are some of the world’s largest fish, measuring 9.8 feet in length and weighing almost 440 pounds. An interesting fact about this fish is that it needs air. Only baby Arapaima have gills; adults have air bladders which help them to breathe and this adaptation helps them to survive in oxygen deficient areas where other fish become lazy. The father takes care of the baby fish and keeps them in his mouth until they grow enough to survive on their own. The arapaima is a carnivorous fish; it uses its mouth to catch fish and even birds that are on the surface of the water. The bony tongue also helps them to chew and crush food.

10. Piranha

Piranhas inhabit South America’s rivers, floodplains, reservoirs, and lakes; they have sharp teeth and have an insatiable hunger. They are omnivorous and rarely attack human beings. These are considered to be important scavengers and predators. Piranhas resort to cannibalism if they are unable to find adequate food in their surroundings to satiate their hunger. It has been estimated that almost 30-60 species of piranhas exist. Their bite is considered to be the strongest in bony fish. With the help of strong jaws and finely serrated teeth, they can tear flesh apart.

9. Vampire Fish

Vampire fish are commonly known as Payara and they are mostly found in Venezuela. They feed on smaller fish, especially piranha. They grab their prey with the help of their long and sharp fangs; these fangs can grow up to six inches and they hunt like a shark. There is a television show called The Monster Fish, hosted by a fish biologist named Zeb Hogan. He has shown this fish in his show. It weighs up to forty pounds. The distinctive features of this fish are its teeth; it has sword-like teeth which bulge out of the lower jaw and they are made of enamel which makes them very strong. It is a prized Amazon game fish. The swimmers are warned to be careful while diving in the rivers that are inhabited by them.

8. Goliath Tiger Fish

It is mostly found in Africa and is known for being a furious predator with large razor sharp teeth. They usually attack in groups and hunt large animals. Attacks on humans are rare. There are two large species: one is the goliath tiger fish and other is the hydrocynus vittatus that is commonly known as the tiger fish, the goliath tiger fish is a giant tiger fish that weigh up to 110 pounds and is mostly found in the Congo River and Lake Tanganyika. They eat any fish that they can easily hunt. These fish use their senses of sight and hearing to find a prey and when they find one, they accelerate their swimming to eat it. They are known as the greatest fresh water game fish in the world. The native people say that a spirit known as ‘mbenga’ enters in the fish and that’s why it attacks human beings.

7. Snakehead

These fish are mostly found in Asia; they have a long dorsal fin, a large mouth, and shiny teeth and are famous for their aggressive behavior. An amazing characteristic of these fish is that they can breathe air and can survive for up to four days without water, they can also get through drought conditions by living in the mud. They are also kept in aquariums and prized for the dinner table and are considered to be valuable as a food source. These predators can reach the length of three feet and they mostly feed on invertebrates like frogs and smaller fish. In their breeding season, they attack anything that they find moving. They are a bit harder to raise as compared to other fresh water fish.

6. Frilled Shark

The frilled fish is a slippery eel-like shark with rows of terrifying teeth. It is found in the Atlantic and Pacific oceans and due to its primitive features, it is also known as a living relic. Its long jaws are terminal; it is outfitted with three hundred trident-shaped teeth that are arranged in about 25 rows. It is also called a living fossil and it is rarely seen by humans. The frilled shark has separate pairs of gills. It was discovered in the 19^th century by a German ichthyologist. It hovers in the water as it is believed that they wriggle in the water like an eel. The female frilled fish are larger in size as compared to male frilled fish. The male range from 3.2 to 3.6 feet and the female range from 4.4 to 4.9 feet. Surprisingly, it is found all over the world, but few people have seen it.

5. West African Lungfish

It is also known as the Tana lungfish. It is mostly found in fresh water habitats of West and Middle Africa, but also in the northern half of Southern Africa. It feeds on mollusks, prawns, crabs and small fish that are within its range. This monster can survive three and a half years without any food and buries itself in mud and does not move unless the conditions become favorable. It lives buried in the riverbeds as the river and floodplains dry up. The biological adaptation of lungs allows lungfish to breathe air and exchange oxygen from the air while the gills allow the extraction oxygen from water. Another adaptation is that it digests its own muscles to obtain nutrients and excretes a mucus cocoon.

4. Black Scabbard Fish

This horrid fish has massive teeth. The black scabbardfish lives between 12-14 years. Their known prey consists of 35 or more fish, including crustaceans, mesopelagic fish, shrimp, teleost fish and many others. They are of great economic importance and prized for food because of the good flesh quality. They mature fairly late and live in delicate deep sea water. They also have long, elongated eel-like bodies and their color is generally a dark metallic black. They reproduce after they reach the age of five to eight years. They spend daylight hours on the seabed, during which time they are inactive, then in darkness, they swim up to mid water and hunt for food.

3. Sea Spider

They are a type of old marine arthropods and they grow massive in size by the process of polar gigantism. Their body is slender, segmented and divided into two parts: one is the head and the other is the trunk. They are long-legged, spider-like organisms. Almost 400 species of sea spiders are known. They are found in shallow waters but can also live in deep water. They camouflage themselves under the rocks and in algae and are mostly found near the seashores. Sea spiders are mostly predators and scavengers; they can swim as well as walk along the seabed. They usually feed on sponges, bryozoans, polychaetes, and cnidarians. They are not actual spiders.

2. Angler Fish

Anglerfish are bony fish that are found worldwide. There is a fleshy outgrowth from fish’s head that acts as a lure. They are called anglerfish because of their method of predation. The jaw and stomach of the anglerfish adapt in a way that they extend to consume a prey double their own size. The anglerfish is known for its angry looks. It is the ugliest organism on the planet, and it lives lonely in the lightless bottom of the sea. The anglerfish has almost 200 species; they live in the depths of the Atlantic and Antarctic oceans. Their color is dark grey to dark brown and they have huge heads with crescent-shaped mouths that are filled with translucent teeth.

1. Sabertooth Fish

The sabertooth fish is famous for its fierce looks. They are deep-sea fish that are named after their oversized curved palatine teeth. They do not have a swim bladder and their stomach is highly distensible. They are considered to be active, visual predators and can swallow prey that is double their size. The head and body is without scales and their body length is about 18 cm. They are mostly situated in tropical and sub-tropical areas of the Atlantic, Indian and Pacific oceans. Their teeth function in an analogous way to snake teeth. Their colour is usually light to dark-brown. Their eyes can be small or large. The sabertooth has a small family of only eight species.