Sawfish: what does it look like and where does it live? Is a sawfish a shark? Sawfish (lat. Pristidae)
This inhabitant of the oceans stands out among others in that on his head he has a bone outgrowth with jagged edges, which really resembles a saw and makes up approximately a quarter of the total body length.
The exact biological name of this fish is the common sawfish, and it belongs to the stingray family. On the back of a sawfish (lat. Pristidae) there are two fins, and one on the tail, and unlike many other rays, it does not have a spike.
Just like sharks, sawfish skin is covered with placoid scales. Due to the great external similarity, sawfish rays are sometimes confused with sawnose sharks, but this is a completely different family of fish.
They can be distinguished by the way the gills are located: in sawfish, like all rays, gill slits are located at the bottom of the head, and in sawnose sharks, on its sides. Moreover, saw fish in size significantly exceeds sawnose sharks.
This species of fish is listed in the international Red Book and lives in the coastal parts of the Atlantic, Indian and Pacific oceans, as well as in the Mediterranean Sea. Sawfish, which live off the coast of the American continent, migrate from south to north in summer, and from north to south in autumn.
The common sawmill does not lay eggs, but reproduces by ovoviviparity. One female Sawfish is capable of producing fifteen to twenty cubs at a time. At the same time, while they are still in the womb, their “saw” is completely covered with skin.
In the open ocean, it is almost impossible to meet saw fish. She chose coastal areas for her habitat, and sometimes she enters shallows, and then one can observe dorsal fins sticking out of the water.
It also happens that it enters large rivers that flow into the ocean, and some of the species of sawfish, for example, the Australian sawfish, have become so accustomed to fresh water that they live in the rivers of the Green Continent all the time.
The diet of sawfish consists mainly of a variety of small animals that live in the sand and silt covering the bottom. It is for this, and not for any carpentry work, that the sawmill needs a saw. With its help, this type of stingray loosens the bottom soil and digs out those unfortunate ones from it, which then go to food.
However, there is also evidence that the saw can be used by the sawmill not only as a shovel, but also as a kind of saber. There is numerous evidence of how these bottom fish quickly burst into flocks of sardines or mullets and how real swordsmen hit their prey with a saw, which they calmly ate after it sank to the bottom. The saw fish became so famous due to its unusual appearance. Previously, there was even a legend that she was able to cut a wooden ship, and that is why even experienced "sea wolves" were afraid of meeting with her. However, in reality, this fish is not at all dangerous for humans, and, like most other species of stingrays, when meeting with it, it often tries to hide quickly.
As for its commercial value, it is very small, since the sawfly meat is rather coarse, although quite edible.
The large-toothed sawfish (Pristis perotteti) is now firmly established in the inland waters of its habitat. For example, the population found in Lake Nicaragua appears to be entirely freshwater and may represent a distinct species from the sawfish found in the waters along the coasts of Central America.
Like many sharks, sawfish produce litters of live young. In the body of a pregnant female of this fish, caught off the coast of Sri Lanka, there were 23 fry. To make the process of pregnancy and childbirth not so painful, the teeth of the fry are covered with a protective shell, and the stigmas remain soft and flexible until the very birth of the offspring.
The sawfish has a very impressive size, but it is still far from a giant freshwater stingray. The average length of her body is 4.5-4.8 meters. There are individuals and more, 6-7 meters. It also weighs a lot - this is how a stingray 4.2 meters long was caught, the weight of which reached 315 kilograms. The heavyweight record belongs to a stingray weighing 2.4 tons. It is a pity that its length is not indicated anywhere.
These stingrays are born already with a long but soft snout with small teeth hidden under a leathery shell so as not to damage the mother. In adults, the length of the "saw" can reach 110-120 centimeters.
Unlike other species of stingrays, the sawfish lacks a spike on its caudal fin. Some people confuse these rays with sawnose sharks, which they closely resemble. How to distinguish them? Everything is very simple. In sharks, the gills are located along the edges of the head, in stingrays, they are located below. In addition, in the latter, the body is flattened, the edges of the pectoral fins are fused with the head at the level of the mouth. All these features, as well as the absence of antennae on the snout, distinguish sawn rays from saw sharks (Pristiophoridae).
Now we have come to the answer to the question - why does the fish need a saw? It turns out that with its help, the stingray digs out small fish hiding from it from the silt and sand. In addition to the fact that the saw serves him as a kind of "shovel", it is also a formidable weapon. Having burst into a flock of fish, the stingray violently begins to swing the "saw" from side to side. After that, he calmly sinks to the bottom and swallows the wounded or "sawn" fish. For humans, this fish is completely safe.
"I'm a fish, nicknamed saw -
I drink whatever comes in the ocean!
And soon your schooner is cut in half
It will disintegrate under a sharp saw!”
Who doesn't remember this funny song from the Blue Puppy cartoon? You will be very surprised, but in fact the sawfish is not a fish at all. Well, not exactly a fish. It belongs to the family of sawfly rays from the class of cartilaginous fish.
There are 7 numerous genera in the family, of which only 7 species of sawfish exist in our time - Asian, Queensland (or Australian), small-toothed, comb, Atlantic, European and green sawfish.
The sawfish has an elongated body similar to a shark in its shape. And on the head there is a long and flat outgrowth of her snout, a growth that strongly resembles a saw in shape (notches resembling teeth are located on it on both sides), it reaches up to a quarter of the length of the body of a sawfish ray, which is approximately 1.2 meters in adult sawfish, and narrows gradually from the base to the end.
The stingray has 4 lateral fins - two on each side, and 2 dorsal, triangles. It does not have a spike on its caudal fin like most rays. The skin of sawfish is covered with the same placoid scales as those of sharks.
The tail part externally merges with the body, and some species have a caudal fin, divided into 2 lobes. The skin color of the stingray is olive gray with different shades in different species, and the belly is almost white.
Sometimes sawnose rays are confused with sawnose sharks, but this is not true, although rays are the closest relatives of sharks. Unlike sharks, stingrays have gills located at the bottom, not on the sides. In addition, sawfly rays will be larger, their body lengths in rare cases reach up to 7.6 meters, but smaller specimens are common - 4.5-4.8 meters, with such a length the slope weighs about 300-325 kg.
The largest weight that was recorded reached 2,400 kg, its length is unknown. The body of rays is flatter than that of sharks, and the edges of the pectoral lateral fins are fused with the head near the mouth. In sawnose sharks, the body length rarely exceeds 1.5 meters, and the “saw” is less flat and thinner than that of sawfish.
When you look at the belly of a sawfish, a pair of gills and a mouth opening together look like a whiny face.
Sawfish lives in the coastal waters of all oceans except the Arctic Ocean, but it is almost impossible to meet it in the open ocean. She often swims in such shallow water that her dorsal fins protrude above the water.
Five out of seven species live off the coast of Australia, and the Australian sawfish is so accustomed to fresh water that it lives in rivers all the time, without swimming out into the ocean.
Sometimes sawfish swim in the mouths of large freshwater rivers during seasonal migrations (summer and autumn). The sawfly, which lives off the coast of America, can go quite far up the river. Sawmills generally feel great in any water - in salty ocean, brackish and freshwater. But they cannot live in water polluted with waste.
Sawfish rays are ovoviviparous fish (an already formed cub is born into the world in the shell of a leathery egg) and can give birth to up to 20 cubs, in which the “saw” is soft at birth and hardens over time. In the womb, the "saw" of the cubs is completely hidden by the skin.
The standard diet of sawfish rays consists of demersal invertebrates.
With a snout, using it as a shovel, it is very convenient for them to pick them out from the bottom of the sea. There is another way to hunt - to break into a flock of small fish, wave your snout-saw in different directions, and then collect a crippled fish from the bottom.
It is generally accepted that the sawfish is not dangerous to humans. However, there have been a few cases of attacks on a person, some with a fatal outcome (there were several such cases in the Gulf of Panama). But, if the fish is not provoked and attacked, in the vast majority of cases it will not touch you.
On the contrary, she will try to hide at your approach. Just try not to step on it when walking in shallow water - stingrays love to bask in the sun, lying in shallow water on the sand.
In past centuries, there was even a legend that a sawfish could saw through an entire ship. In fact, her strength is not enough for such a destructive action. Don't touch the sawmill and it won't touch you. And the song from the cartoon is just a figment of the imagination of its author.
Sawfish meat is coarse, but quite edible, but it does not represent a special nutritional value. However, due to the pollution of coastal waters in some places, some species of sawfish are on the verge of extinction and are listed in the Red Book.
Thus, it can be said that a person poses a much more danger to sawfish than vice versa. After all, it is due to human activities that coastal waters are polluted. And some peoples consider the saw of this fish to be a valuable decoration of their home and even a weapon!
That's why the number of sawfish has drastically declined, and only a few people on Earth can boast of having seen them alive.
The sawfish (lat. Pristis pristis) has a unique snout that is more than a quarter of its body length. It belongs to the Pristidae family of the order Sawtooth rays (Pristiformes).
Along with sharks, it occupies its niche in the class of cartilaginous fish (Chondtichthyes), since its skeleton is built from cartilage. Some representatives of this family are able to feed on plankton, while others prefer to hunt as avid predators.
Behavior
The sawfish is found in the seas of the temperate climate zone from the coast of Angola to Portugal. Occasionally found in the western Mediterranean Sea.
Constantly living in shallow coastal waters, inquisitive fish often swim into the mouths of rivers to satisfy their curiosity. It keeps near the bottom, where you can always profit from something. Slowly swimming near the bottom of the sawfish does not arouse suspicion in small fish.
It currently has the status of an endangered species. Because of its tasty meat and fatty liver, it has always been considered a good trophy. The meat of fish that has reached a length of one meter is most valued.
A fish caught in the net with its sharp snout can spoil the tackle, so the fishermen consider it a personal enemy. Souvenirs are made from its rostrum, which are popular with tourists.
Sawfish can reach nine meters in length, not including a three-meter rostrum. Some gigantic specimens can weigh about 2500 kg.
After mating, the fertilized eggs remain in the mother's body, where the process of embryo development takes place. Small saws of newborn cubs are hidden under a protective shell in order not to injure the mother during childbirth. At one time, the female is able to give birth to about 20 cubs.
While swimming, the fish bends with its whole body, giving itself speed with the help of a powerful tail fin. For a person, it does not pose any danger until it is shot from an underwater gun.
The mouth opening located in the lower part is able to easily collect all kinds of mollusks, various echinoderms and slugs from the seabed. Having burst into a school of small fish, the predator begins to wield its saw like a saber, and then slowly picks up wounded or killed prey from the bottom. If a fish gets stuck on the saw, it will carefully remove it, cleaning its weapon on the bottom, and then swallow the catch with gusto.
Description
The body length of the sawfish reaches 6 m, and the average weight is about 250 kg. On the flattened head on top of the snout are large eyes. Behind them are pronounced splashes.
The snout resembles an elongated flat blade, in which the sides are equipped with 16-20 large tooth-like outgrowths. Very wide ventral fins with their front edges fused with the head at the level of the mouth. The spindle-shaped body gives a resemblance to a shark. The back is grayish-brown in color, and the belly is light.
The two dorsal fins are almost the same size. There are leather folds on both sides of the tail shaft. The strong caudal fin has practically no lower lobe.
The average life expectancy of sawfish in natural conditions is about 25 years.
The boundless latitudes of the ocean contain a very large number of different inhabitants. They differ from each other in interesting shapes, bizarre names, coloring and naturally external features. Let's single out several inhabitants of the deep sea, which have interesting properties and external features - sawfish. The full name of the fish is sawfly(from lat. Pristidae).
This difficult inhabitant of the mysterious depths of the ocean differs from its "neighbors" in a bone outgrowth on its head, which is very reminiscent of a saw. In this case, the saw is almost half the length of the fish itself. It belongs to the stingray family, but does not have a spike in its structure, which is a distinctive feature of many members of the subspecies. There are several varieties of sawfish - shark-saw and stingray-sawfish.
- Quite often, sawfish are confused with the so-called sawnose sharks. The thing is that outwardly they are very similar and in both the skin consists of placoid scales;
- Pila fish was listed in the Red Book;
- Basically, these fish live on the coasts of the Atlantic and Pacific Oceans, as well as in the Mediterranean Sea;
- Representatives of this species give birth to fully formed children in the egg, they never laid eggs;
- It is absolutely impossible to meet her in the open ocean, but she feels great in coastal areas;
- Sometimes they fall into large rivers that flow into the ocean and remain to dwell in them;
- They feed on very small animals that live on the bottom of sand or silt;
- There has long been a legend that a saw fish could easily saw through a whole wooden ship;
- The meat of this fish is usually not given much attention due to its toughness;
- The length of the fish is from 4.5 - 5 meters. But sometimes there are individuals with a body length of about 7 meters. The weight category is also rather big, about 300 kg;
- Fish are born with a long and soft saw blade covered with small teeth and its length in adults is approximately 100-120 cm;
- The saw is her main weapon, so she sometimes gets her own food;
- For a person, it does not pose any danger;
- In nature, there is not only a sawfish like a shark, but also like a stingray;
- Many cultures used the basic image of the sawfish as a tribal symbol (Aztecs);
- The sawfish is the main symbol of the central bank of West Africa;
- We can meet the sawfish in the blue puppy cartoon;
- The pregnancy of a female fish lasts for 5 months and the offspring reaches 14-15 individuals;
- The fish saw is very sensitive to the electric field, which is formed as a result of the movement of potential victims, and in this case it is easier for it to hunt, therefore this species can be attributed to dangerous and dexterous predators;
- Scientists have proven that some species of sawfish can reproduce without the direct participation of males in this process, and their cubs will have an exact copy of the mother - parthenogenesis (this is due to the fact that this species is disappearing, and nature helps to restore the natural balance). Recently, this process of reproduction is spreading and occurs quite often.
Differences between saw shark and saw stingray
Let's look at some important differences between these species, as they often confuse even the most experienced researchers.
- The saw shark does not have significant dimensions compared to the saw-bearing rays (6 m or more), their length, together with the tool, is only about 1.5 m;
- Another significant difference involves the presence of gill slits in sharks on both sides of the body, in rays in the lower part of the body;
- These species are also distinguished by the presence and shape of the fins - in sharks they look separated from the body, and in stingrays they differ in a smooth transition to the body;
- Another significant difference concerns directly the "tool" of these two types of fish. In sharks, the "saw" is slightly narrowed towards the end and the teeth on it are of different sizes, especially in the middle of the row. In stingrays, on the contrary, the “saw” is very neat, the same size and the teeth have the same structure and shape;
- An interesting fact is that saw sharks recover broken teeth over time, while rays do not grow back even after minor damage;
- On the "tool" sharks grow long whiskers, which the stingray does not have;
- Sharks move with the help of the well-known fin, so it is very easy to distinguish it from a stingray, which moves with wavy body movements;
- Many people are interested in the meat of sawnose sharks, in some countries it is a local delicacy, which cannot be said about the meat of sawfish.
The main use of the "tool" of the fish
Fish of this species use their weapons at all stages of hunting and catching their potential victims. They strike animals with their electric weapons and impale their prey on the teeth that run the entire length of the saw. The speed of their movements is simply elusive. They deftly manage the tool and immediately inflict several side blows on the victims.
The saw in their case acts as the main electric search engine, which easily finds various types of animals that live in the depths of the ocean. It is not difficult for them to detect and grab prey that was several layers of water higher than they are.
Now these listed interesting facts about the life of fish of various species will help even the most inexperienced ichthyologists to easily find the distinguishing features between them. Their most important difference is already visible to the naked eye - it is hidden in their different names. There is an opinion that the sawfish, thanks to its tool, is very clumsy, but paying attention to the way they hunt, prey and dexterity, thanks to the same tool, this myth was simply dispelled.
Sawfish have an elongated, shark-like body. The most noticeable sign is the so-called saw - a bone outgrowth on the head, framed on the sides by teeth. The saw is about a quarter of the body length of the sawflies. They have two dorsal fins and a large, spineless caudal fin. The skin, like that of sharks, is covered with placoid scales.
Sawfish rays should not be confused with sawnose sharks, which experienced convergent evolutionary development in relation to them and acquired a similar appearance. Compared to sawnose sharks, sawnose sharks are much larger and reach 4.7 to 7.6 meters.
Spreading
reproduction
Classification
- Asian sawmill ( Anoxypristis cuspidata)
- Queensland sawmill ( Pristis clavata)
- Small-toothed sawmill ( Pristis microdon)
- Sawmill comb ( Pristis pectinata)
- Sawmill Atlantic ( Pristis perotteti)
- European sawmill ( pristis pristis)
- sawmill green ( Pristis zijsron)
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Synonyms:See what "Sawfish" is in other dictionaries:
Exist., number of synonyms: 3 sawfish (3) fish (773) stingray (40) ASIS synonym dictionary. V.N. Trishin ... Synonym dictionary
Saw fish, saw fish... Spelling Dictionary
To fight like a fish on ice, to fish in troubled waters, it's like a fish. Dictionary of Russian synonyms and expressions similar in meaning. under. ed. N. Abramova, M .: Russian dictionaries, 1999. fish fish, fish, fish, fish, fish, fish, fish, live bait, ... ... Synonym dictionary
SAW FISH, saw fish, female. (zool.). A predatory fish, a genus of a stingray (see scat3), similar to a shark, with a strongly elongated snout, which has processes on both sides that resemble saw teeth. Explanatory Dictionary of Ushakov. D.N. Ushakov. 1935 1940 ... Explanatory Dictionary of Ushakov
SAW FISH, saw fish, female. Predatory fish from the stingray order with processes on the muzzle resembling saw teeth. Explanatory dictionary of Ozhegov. S.I. Ozhegov, N.Yu. Shvedova. 1949 1992 ... Explanatory dictionary of Ozhegov
sawfish- SAW FISH, fish saws, f Predatory fish from the order of rays with processes on the muzzle resembling saw teeth. Sawfish are occasionally caught in the Caribbean... Explanatory dictionary of Russian nouns
Exist., Number of synonyms: 1 fish (773) ASIS Synonym Dictionary. V.N. Trishin. 2013 ... Synonym dictionary
G. Predatory fish of the stingray suborder with a long snout, which has processes on both sides that resemble saw teeth. Explanatory Dictionary of Efremova. T. F. Efremova. 2000... Modern explanatory dictionary of the Russian language Efremova
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