Black pacu (Colossoma macropomum). Pacu - freshwater fish with teeth Fish with human teeth name

Some inhabitants of the underwater world are familiar to us, others we have eaten, and not everyone even knows about the existence of others. There are species of fish that we didn’t even know existed. They are completely different: huge and tiny, dangerous and not so dangerous, with bizarre shapes and strange names. From this article you will learn that there is, for example, fish with human ones; it is probably not known to every person. Many strange fish live in the underwater depths, we will also talk about them. So, let's begin our journey into the fascinating and exotic world of fish.

Paku

This is the most real fish with human teeth. Pacu is a freshwater inhabitant of many rivers in South America. It is also found in the Orinoco and Amazon basins. It also reached Papua New Guinea, where they began to artificially breed it in order to raise it to a higher level. Fish with human teeth belongs to the same genus as piranha (Serrasalminae), although their preferences and habits differ. Piranha is a carnivorous species, but pacu eats absolutely everything and prefers vegetation.

Fish with human teeth: why is it called that?

The most important difference between pacu and piranha is the structure of the teeth. Piranha, as we know, has sharp teeth, which many compare to a razor. But a fish with human teeth has a completely different jaw structure, which is why it is called that. If you look into her mouth, you can really get scared and horrified. Her teeth are square and straight, very human-like. Fish use them mainly for chopping fruits and nuts, although they can also feast on invertebrates. It was her craving for nuts that once deprived two fishermen of their genitals in Papua New Guinea. As you can see, although the pacu is not such a predator as the piranha, the strength of its jaws can still cause irreparable harm. But in the USA, the fish is legal, and anyone can purchase it and place it in an aquarium. But for some reason people don’t take into account that a pacu can grow up to a meter and weigh about 30 kg. Therefore, then the owners simply release her into the nearest body of water. This can explain the fact that fish appeared in Denmark and England. Some sources report that pacu is already available even in Russia.

Lion fish

Continuing to talk about what kind of worlds exist, we cannot lose sight of this cute creature. The lion fish is mostly motionless among the corals, only sometimes swimming from one place to another. It attracts the attention of people and numerous aquatic inhabitants with its unusual coloring, dorsal and pectoral fins, which resemble a large fan. However, behind the bright appearance there are sharp needles that secrete poison. A fish will never be the first to attack a person, but if he accidentally steps on it or even touches it, then just one injection will greatly worsen his general well-being. And after several injections, a person will not be able to swim to the shore on his own; he will need help.

frilled shark

This predator is called that because of the brown formation on its body that looks like a cape. And due to the large number of folds on the skin, it is also called a corrugated shark. Scientists believe that such formations on the skin serve as a reserve of body volume to accommodate large prey in the stomach. Due to its teeth bent inward, this inhabitant of the waters is unable to crush food, so it swallows its prey whole. This is where folds in the skin that can stretch can come in handy. You can see a shark in any ocean, but not in the Arctic.

Blob fish

Some types of fish are truly capable of striking with their appearance. The drop fish is one of them. It looks so unattractive that it is considered one of the most terrible fish on the planet. They live off the coast of Tasmania and Australia, and at the moment there is a threat of their complete extinction. The body of this ugly fish consists of a gelatinous mass, the density of which is less. It has absolutely no muscles, but this does not prevent it from lazily opening its mouth and swallowing everything that swims in front of it (if it is edible).

Big Mouth

This unusual individual lives in the Atlantic, Pacific, and Indian oceans. The body of the largemouth is narrow and long (up to 1 meter). And the mouth is gigantic in size (a third of the entire body length), and can even stretch. This unusual inhabitant of the oceans has no scales, ribs, or normal bone structure. The thin body on the tail turns into a thread, at the end of which there is a luminous organ. Due to the presence of only light cartilage and deformed bones in the skeleton, the fish is very light, it has tiny eyes and a very small skull. The size of the mouth allows the largemouth to swallow prey that is larger than itself in size.

Bagswallow

This deep-sea inhabitant is also called the black eater. This fish grows no more than 30 cm in length, and it was named so because of its ability to completely absorb prey that is several times larger than itself. For example, it can easily swallow prey that is 4 times longer and 10 times heavier than the bag swallow itself! Its jaws are very large, and its fangs help hold the prey while the fish pushes it into its stomach. When food begins to decompose in the stomach, a lot of gas is formed there, which is why the fish involuntarily rises to the surface of the water. Very little is known about these inhabitants, since it is simply impossible to observe their way of life in their natural conditions.

Macropinna smallmouth

It is impossible to see this fish and not scream in fear and surprise at the same time. Why? Because she has a transparent head! The barrel eye (second name) can easily track prey through such a head with its tubular eyes. The specimen was discovered only in 1939. In her usual environment, she is motionless, and if she decides to move, she does so in a horizontal position and very slowly. Previously, it was completely unclear how the eyes of a fish work, because there are olfactory organs right above its mouth, and the eyes are located right inside its surprisingly transparent head, and they only look up. In 2009, scientists finally found out that macropinna has an extremely unusual structure of the eye muscles. It turns out that the eyes of a fish are usually in a vertical position, and if there is a need to look ahead, then it moves them to a horizontal position! Once this happens, she can see her mouth and grab her prey!

Anglerfish

This is a real deep sea monster. It is called not only an angler fish, but also a devil fish. This one has bare skin, a spherical body shape, and the female has a “fishing rod”. This predator hunts thanks to a special growth on its back - during the process of evolution, one section of the dorsal fin was separated from the others, and at its end a transparent sac appeared in which bacteria live. What's most interesting is that the angler fish can make these bacteria light up! He regulates this himself, narrowing or expanding blood vessels. The female can grow up to 65 cm, and the male - only 15-45 mm! When the male ends puberty, he attaches himself to the female with sharp teeth (usually from the side). Soon he fuses with her tongue and lips, and his teeth, intestines, and eyes are reduced in such a way that he becomes a simple appendage that has lost its independence.

Conclusion

From this article you learned what unusual fish exist (photos above). It doesn’t matter whether they pose a danger to humans or not, you shouldn’t be afraid of them. After all, the main thing is to have information and know what each individual is capable of.

Black pacu (lat. Colossoma macropomum), which is also called the herbivorous piranha pacu or tambaqui, is a fish of the characin family, that is, its brothers are neon and tetra. But the coincidences end with the name of the genus.

The black pacu is the largest characin living in South America and in no way resembles its smaller counterparts.

Pacu fish reach up to 108 cm in length and weigh about 27 kg, which is impressive. However, more often they are about 70 cm, but this is prohibitive for an amateur aquarium. No wonder it is also called the giant pacu.

Habitat in nature

The black pacu (also called the brown pacu), also known locally as the tambaqui, was first described by Cuvier in 1816. We live throughout the Amazon and Orinoco basins in South America.

Also called pacu, giant pacu, tambaqui, gamitana and cachama.

Video about a natural reservoir in Brazil, at the end of the video there is underwater footage, including a flock of pacu

In 1994, they were introduced to Guinea as a commercial fish, to the Sepik and Ramu rivers. They have also spread widely throughout South America, including Peru, Bolivia, Colombia, Brazil, Cuba, the Dominican Republic, and Honduras. And Northern - USA.

Solitary, they feed on insects, snails, decaying plants and small fish.

Adult fish swim into flooded forests during the rainy season and eat fruits and grains.

The commentator says that they feed on fruits that have fallen into the water, which are abundant there.

Description

The black pacu can grow up to 106 cm and weigh up to 30 kg and live up to 25 years. The body is laterally compressed, the body color is gray to black, sometimes with spots along the body. The fins are black.

Very often, black pacu are confused with piranhas while they are small. The juveniles are very similar, but black pacu are rounder and wider than piranhas.

The easiest way to identify it is by the lower jaw; in piranhas it protrudes forward.

Difficulty in content

This is a very large fish and it is better to keep it in commercial aquariums, since not many people can afford it at home. Although she is very unpretentious and simple.

It is not too demanding on water parameters, as long as they are not extreme, and the same applies to feeding.

The black pacu is an interesting, very unpretentious fish in keeping and feeding, which even has its own personality. Sounds like the perfect aquarium fish, doesn't it?

But the biggest problem in keeping it is that the black pacu grows quickly and hugely; it quickly outgrows even very large aquariums.

The problem is that careless sellers often sell them very small under the guise of piranhas. Although these fish are very similar, the pacu is less aggressive and not as predatory.

However, this does not change the fact that the black pacu will swallow any small fish in the aquarium without a second thought.

The black pacu is definitely not a fish for everyone. To keep one, you need 1000 liters for juveniles, and about 2000 for adult fish. For such an aquarium you need very thick glass, since in fright a black pacu can break it.

In warm climates, black pacu is sometimes kept in ponds, but due to its dark color, it does not look very good there.

If you are not afraid of the volumes required for this fish, then otherwise keeping it is not difficult.

Feeding

What to feed the paku? Black pacu are omnivores, and in nature they eat fruits, grains, insects, snails, invertebrates, and carrion. The aquarium will have both artificial and live food.

Anything goes for him - snails, worms, bloodworms, fruits, vegetables. And small fish, so keeping them with those that a pacu can swallow is definitely not worth it.

The main requirement is a very large aquarium, for adults from 2 tons. If you can afford one, then the difficulties end there.

They are completely undemanding, disease resistant, and eat anything. The only thing is that they need very powerful filtration, since there is a lot of dirt from them.

They live in the middle layers of water and need free space to swim.

The best decorations are driftwood and large stones; you don’t need to plant plants at all; they are food for the black pacu.

They are a little timid, there is a sudden movement and they panic, throwing around the aquarium and hitting objects and glass...

Compatibility

Adults are solitary, but non-aggressive. Young people are more cocky. Adults will eat any small fish they can swallow; large fish are not in danger.

It is best kept alone or with an equally large fish.

Sex differences

The male has a sharper dorsal fin, has spines on the anal fin, and is brighter colored than the female.

Breeding

The black pacu is not bred in an aquarium due to its size.

All individuals that go on sale are bred in ponds and on farms.

Pacu is a South American freshwater fish found in most rivers in the Amazon and Orinoco basins of the Amazon lowland. Pacu also made their way to Papua New Guinea, where they were artificially bred to help the local fishing industry. The pacu shares common roots with the piranha, being in the genus Serrasalminae, although they have different habits and preferences. Piranha is a carnivorous species, while Pacu is omnivorous, with a vegetative preference. The difference is obvious in the structure of their teeth. The piranha has razor-sharp teeth, while the pacu's are squarer, straighter, and eerily similar to human teeth.

Pacu use its teeth mainly to crush nuts and fruits, but they also sometimes eat other fish and invertebrates. They commonly eat floating fruits and nuts that fall from trees into the Amazon, and in several cases have even attacked the testicles of male swimmers, confusing them with nuts. They earned a dangerous reputation after they castrated several local fishermen in Papua New Guinea. So when the fish were discovered in several lakes in Denmark, and later in Washington, New Jersey and Illinois, there was a bit of panic.

While pacu are not aggressive carnivores like piranhas, their crushing jaw system can be dangerous. One baby needed surgery after a pacu bit his finger at Edinburgh Zoo in Scotland. The manager then commented on the incident by saying that "Paku will eat anything, even a child's wiggling fingers."


These fish are legal in the United States and can be purchased at pet stores. The problem is that many aquarium owners do not realize that pacu can grow over a meter long, which is too long for a typical home aquarium. When a pet outgrows their fish tank, owners end up releasing it into nearby lakes. This explains the fact that the fish began to be found in many bodies of water outside of its natural habitat.

If you want even more creepy underwater inhabitants, then there is a separate photo strip for this, where as many as 25 equally strange creatures have been collected.

These curious-eyed fish usually swim leisurely around the aquarium. Looking at them, it is difficult to guess that these are close relatives of the terrible ones. Yes, the pacu fish is from the piranha family, but it mainly feeds on plant foods and does not pose a danger to humans.

The name pacu is used for several large species of fish of the piranha family (Serrasalmidae) that live in the rivers of South America. The number of teeth in the common piranha (Pygocentrus nattereri) and the pacu is the same, but their structure is very different. The teeth of the predatory Pygocentrus nattereri (also called the red piranha) are pointed with a clearly visible mesial bite (with a protruding lower jaw).

Pacu teeth are straight, rectangular (sometimes called square). The bite may be slightly mesial or distal: the teeth of the upper jaw are slightly protruded, and the upper jaw may protrude slightly forward. Or both jaws are in the same position: neither of them protrudes.

Which pacu are popular among aquarists?

The homeland of all pacu is the reservoirs of the Orinoco and Amazon basins. They are part of the neotropical fauna. They are often sold as herbivorous piranhas. But in order for pacu to become real pets that delight the owner, it is necessary to provide proper conditions and care for them. After all, these fish are not small! Typically, aquariums contain black (aka brown) and red pacu.

About the Latin names of pacu

The Latin scientific names used in this article correspond to the latest updated fish database data. Based on the data from this site, it is concluded that the Russian names black and brown pacu refer to the same species, the scientific name of which is Colossoma macropomum. Acceptable (correct) synonyms are the following Latin names: Colossoma nigripinne and Piaractus macropomus. The authors of articles on some Internet resources consider the black pacu as a separate species and use the name Colossoma brachypomum for it, which is erroneous, because according to the fishbase website this name is synonymous with the Latin name for the red pacu (Piaractus brachypomus) and, therefore, applies to Russian name for red paku.

About the red pacu

Several Russian names are used for this pack. Most often it is called the red pacu, sometimes the name red-breasted pacu is used, and very rarely - the two-toothed colossoma. According to fishbase, the currently accepted correct Latin scientific name is Piaractus brachypomus, which has synonyms: Colossoma bidens means two-toothed colossoma; the second frequently used synonym is Colossoma brachypomum. The name Colossoma branchypomus cannot be used for this species because there is a typo in the last syllable.

How to distinguish a red pacu from a red piranha

Due to its appearance, the red pacu fish at a young age is often mistaken for the dangerous predatory red piranha Pygocentrus nattereri. Especially if she swims in a species aquarium, near which there are no labels with the names of the fish. Indeed, these two fish are very similar and have almost the same characteristics:

• laterally compressed tall body with small silvery scales;
• the gill cover in the lower part and the belly are red;
• fins (paired ventral and anal) are also bright red;
• the edge of the caudal fin with a striking black stripe.

The main difference between these two types is the structure of the teeth. Let's look at the photo of the red pacu fish, pay attention to the open mouth. We see rectangular teeth, very reminiscent of human ones. The teeth are large and strong with a wide top, so the fish can easily crack nuts.

But is it really necessary to look into the fish’s mouth to understand whether a red piranha or a pacu is swimming in an aquarium? And how to do this? No need to look into your mouth. Take a close look at the closed jaws of the fish. If the lower jaw protrudes forward very strongly, there is a bloodthirsty piranha in front of you. If the jaws are approximately the same, it is a vegetarian red pacu.

Habitat, age and size

The habitat of the red pacu or two-toothed colossoma are numerous tributaries of the Amazon and Orinoco and the rivers themselves. There is evidence that this species has been recorded in Argentina.

This is an omnivorous fish, but the basis of its diet in natural conditions is nuts, which it cracks with its flat teeth and strong jaws. It practically does not eat meat; it can feed on insects and rotting plant remains. This is a fast-growing species and can reach 30 centimeters in length by the end of the first year of life. It is the subject of aquaculture and commercial fish farming. A popular species among aquarists.

The maximum recorded length of a red pacu is 88 cm, the largest weight is 25 kg. There is information about the maximum recorded age of this species, which was 28 years.

About the brown pacu

The brown pacu is best known by its Latin name Colossoma macropomum, although there are also synonyms: Colossoma nigripinne and Piaractus macropomus. In nature, they live in the Orinoco and Amazon basins.

Position in the fish system: class Ray-finned fish, order Cyprinidae, suborder Characinidae, family Piranhaidae.

An external difference, characteristic of all fish of the characinoid suborder, is a small adipose fin located behind the dorsal fin in front of the caudal fin. This pacu fish is the largest representative of this suborder in South American waters. With its tall, laterally compressed body, it resembles an ordinary piranha. However, it is well distinguished by color: the body is painted in shades of black and gray, so it has another name - black pacu. This large fish has large eyes, in which you can notice curiosity about everything that is around.

The usual size that most fish of the species Colossoma macropomum reach in nature is about 70 centimeters. The maximum recorded body length is 108 centimeters, and published data indicate the greatest weight - 40 kilograms. The brown pacu has 10 percent body fat (a fairly high figure), has tasty meat and is an object of fish farming. These fish with good immunity were introduced into many large rivers in tropical America and even into the rivers of Southeast Asia to be raised for food.

Nutrition and lifestyle

Herbivorous pacu fish are often called fish with “human teeth”. Their teeth bear a vague resemblance to human molars. Therefore, they very easily eat grain crops, fruits and nuts, and plant debris that they find in the water. The brown pacu is no exception; at the same time, it can also eat small fish, insects and invertebrates.

The diet of young individuals consists of zooplankton, snails and insects. And only with age do fish switch to a preferably plant-based diet.

The brown pacu probably breeds during river floods and in flooded floodplain forests. The fishbase website reports that juveniles and “teenagers” live in the black waters of the floodplains until they reach sexual maturity. And adult specimens remain in flooded forests for five months after the flood, and then, apparently, return to the rivers.

The black pacu leads a solitary lifestyle, and this differs from the natterer piranha.

The difficulty in maintaining any pacu is the need to purchase a sufficiently large tank, which can weigh about one ton. In such an aquarium it is necessary to install powerful filters that will maintain high water quality. The heater should maintain warm water in the aquarium (about 26-28 C), an aerator and lamps for lighting are also needed.

In the photo of the red pacu fish, the decorations of the aquarium are slightly visible - large rocks. Large driftwood can also be placed. It is better to use only artificial plants for decorative purposes; any living plants will be eaten by fish.

The pacu's diet in the aquarium should be balanced. The approximate composition of a serving may look like this - small pieces of vegetables and fruits (apple, cabbage or zucchini), combined with meat (shellfish or shrimp).