There are several animals that are similarly small in size and capable of inducing primal fear in humans. Apparently, it is no coincidence that both are members of the arachnid class, although the scorpion branch is much older, over 400 million years old. In fact, some prehistoric scorpions were enormous, reaching up to 70 cm (2 feet) in length.

Although today's scorpions are somewhat smaller, there are still some species that are still deadly. All 1,750+ species of scorpions are armed with a venomous stinger located at the tip of their tail, but only about 20 of them have venom strong enough to kill a person. Of these "medically important" species, all but one are members of the Buthidae family.

The sting of a scorpion is designed for both hunting and defense. However, scorpions often prefer to hunt their prey not with venom but with brute force and therefore save their stinger for defense. Most scorpions prey on insects, although large scorpions are actually capable of catching vertebrates such as mice.

The venom itself is a mixture of fast-acting toxins such as neurotoxins and enzyme inhibitors. With the exception of the top three scorpions on this list, a scorpion sting is unlikely to kill a healthy adult, but it does provide an unpleasant experience. Symptoms range from something like a bee or wasp sting to convulsions, shortness of breath, and even death.

It is estimated that 1.2 million scorpions sting every year worldwide, which leads to approximately 3250 deaths, which also indicates a fatality rate (0.27%). Of this number of deaths, about 1,000 occur in Mexico.

Below is a list of the world's most deadly scorpions, which only covers 7 species. That's because most of the 20+ dangerous scorpion species are closely related, so for the sake of interest, we've limited the list.

7. Spitting black fat-tailed scorpion (lat. Parabuthus transvaalicus)

A photo. Black fat-tailed scorpion (lat. Parabuthus transvaalicus)

Also known as the South African fat-tailed scorpion, this is one of the largest species in the Buthidae family, reaching up to 15 cm (6 inches) in length.

It is often said that if a scorpion has small claws and a thick, powerful tail, then this indicates a stronger sting. Theoretically, this is because a scorpion armed with deadly venom would not have to rely on its claws to catch and immobilize its prey.

This is certainly true of the spitting black fat-tailed scorpion, which is considered the most dangerous scorpion in South Africa. The lethal dose is 4.25 mg/kg, which is comparable in strength to cyanide. The size of scorpions and the ability to inject a large dose of poison contribute to the size of their tail.

An interesting fact about Parabuthus transvaalicus is that it produces two types of venom: the first is "preventive", which requires less resources to produce and is used to immobilize smaller prey or deliver a warning bite. If it uses a different venom, then it is a more toxic option, allowing the scorpion to fight larger prey or save its own life.

Generally speaking, a healthy adult will be very unlucky if he dies from the sting of this scorpion, since the mortality rate is less than 1%. But this does not mean that it will be even a remotely pleasant experience! In every third case, intense pain, sweating, salivation, muscle cramps and palpitations may occur.

Oh, and as an added bonus (you guessed it!) A spitting scorpion can spit its venom up to 1 meter (3 feet), causing temporary blindness and possibly permanent eye damage.

6. Yellow fat-tailed scorpion (lat. Androctonus australis)

A photo. Yellow tree scorpion (lat. Androctonus australis)

The Latin name for this group of scorpions is called Androctonus (Androctonus), which translates as "killer of men." This is fitting, as they cause several deaths every year in the dry regions of North Africa and Southeast Asia.

Together with the imperial scorpion (lat. Pandinus imperator), they are one of the most popular species in the exotic pet trade. This fact further increases the likelihood of human contact.

The well-known name of this species is associated with a powerful tail, whose only purpose is to stick a stinger into prey or an attacker. The venom injected from the bite of the Arabian fat-tailed scorpion is one of the most potent neurotoxins of any scorpion. These fast-acting poisons attack the central nervous system, resulting in paralysis and, most notoriously, respiratory failure.

Being highly venomous, the yellow fat-tailed scorpion (yellow tree scorpion, southern Androctonus) is a tough nut to crack. While the desert is known for being inhospitable, there are few animals that can survive a sandstorm. Most of them will burrow into the sand for shelter, but not these thick tailed scorpions. These scorpions are known for being able to withstand sandblasting whirlwinds powerful enough to strip paint off steel without any sign of damage. Apparently, this is due to the special surface of its exoskeleton.

5. Arizona tree scorpion (lat. Centruroides exilicauda)

A photo. Arizona tree scorpion (lat. Centruroides exilicauda)

At less than 7.5 cm (3 in) in length, this tree scorpion is considered a . As the name suggests, it is found in the deserts of Arizona (California and Utah).

The potentially lethal neurotoxic venom is known to cause severe pain that has been described as convulsions from electric shock. In more serious cases, numbness, vomiting and diarrhea occur, and then death can occur.

Over 800 people were killed by the Arizona tree scorpion in Mexico during the 1980s. If left untreated, the bite has a mortality rate of 1 to 25% depending on the victim's age and general health. Fortunately, there is an effective antidote these days, which is why there hasn't been a single death in Arizona in over 40 years.

4. Arabian fat-tailed scorpion (lat. Androctonus crassicauda)

A photo. Arabian fat-tailed scorpion (lat. Androctonus crassicauda)

The Arabian fat-tailed scorpion (Androctonus fat-tailed) is a relative of the yellow fat-tailed scorpion. As the name suggests, it is found throughout the Arab world in countries such as Saudi Arabia, Iran, and Turkey, and can also be found in North Africa.

The Arabian fat-tailed scorpion is a medium-sized scorpion that preys on a range of predatory insects and spiders, including lizards and small rodents.

Along with the fact that he has a potentially deadly poison, he also has a very aggressive character.

3. Brazilian yellow scorpion (lat. Tityus serrulatus)

A photo. Brazilian yellow scorpion (lat. Tityus serrulatus)

You may have already guessed by the name of the scorpion that this scorpion can be found in Brazil. But the very name of the scorpion does not convey the fact that this is the most dangerous scorpion in South America.

Unfortunately, this species comes into too much contact with humans and stings thousands of people every year. In the best cases, the victim becomes intoxicated after the painful sting, but several secondary symptoms may appear, such as nausea and palpitations. As the poison spreads throughout the body, a state of hyperesthesia can set in, making the person extremely sensitive to even the slightest touch on the body.

More severe bites can lead to abdominal cramps, vomiting, and difficulty breathing. For the elderly and the very young, there is a real risk of death from cardiopulmonary failure.

Even though the Brazilian yellow scorpion uses its venom sparingly, resulting in low lethality, it still results in a high number of deaths every year.

2. Yellow scorpion (lat. Leiurus quinquestriatus)

A photo. Yellow scorpion (lat. Leiurus quinquestriatus)

This scorpion has several names: deathstalker, deathstalker, which say that it is difficult to avoid. At only about 58 mm (2.5 inches) long, this is one of the few scorpions you wouldn't want to find in your trunk. It is distributed throughout North Africa and the Middle East. This scorpion is armed with an extremely painful sting, which contains a cocktail of powerful neurotoxins (chlorotoxin) and cardiotoxins, with its miniature size and insignificant-looking ticks.

The yellow scorpion is one of the very few scorpions that poses a serious danger to healthy adults. However, most adult males can survive a bite, due in part to innate resistance to the venom. In any case, it will not be the most pleasant experience.

1. Indian red scorpion (lat. Hottentotta tamulus)

A photo. Indian red scorpion (lat. Hottentotta tamulus)

Typically, red is one of the warning colors in the wild and the Indian red scorpion is certainly no exception to this rule. Possibly the most dangerous scorpion in the world, this arachnid should be avoided.

Found in Eastern India, Pakistan, Sri Lanka and Nepal, this scorpion hunts at night, feeding on insects and sometimes even small lizards and mice. At almost 9 cm (up to 4 inches) in length, this is a fairly large scorpion, but as we know, size doesn't mean anything in the scorpion world. They have very strong poison, as well as the bite itself. Indian red scorpions due to this show high mortality rates, somewhere between 8% and 40%. As with all scorpions, this rate is high among older and younger people.

Although we do not have lethal dose (LD50) statistics for Hottentotta tamulus, this is close to its relative Hottentotta saulcyi, which has a LD50 of 1.1 mg/kg, about the same as the strychnine poison. The symptoms are too unpleasant: severe pain, vomiting, sweating and convulsions. The really dangerous symptoms that affect the functioning of the heart and lungs lead to pulmonary edema (fluid in the lungs), which is the main cause of death. This happens 24 hours after the bite.

Video. Indian red scorpion

This species of scorpion, endemic to North Africa, is also found in the Middle East. Some people keep these creatures, whose body length reaches only eight centimeters, as exotic pets. But, despite their size, these scorpions are considered the most deadly in the world among all scorpions.

Let's take a closer look at it...

The Leiurus quinquestriatus scorpion, which lives in a number of regions around the world, from North Africa to the Middle East. Depending on the area in which they live, they have a different color.

This family of arachnids has other names: yellow scorpion, thedeathstalcer scorpion, Omdurman scorpion or Israeli desert dweller scorpion. On average, it lives 5 years and can grow up to 11.5 cm in length. The adults feed on large insects and crickets, while the young feed on crickets and small insects.

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The sting of a yellow scorpion is considered extremely dangerous. The venom secreted by scorpions contains a strong mixture of neurotoxins that can cause intense and unbearable pain, leading to fever, coma, convulsions, paralysis, and death.

Females are larger than males, which helps them perform their reproductive functions. The most poisonous scorpion Leiurus quinquestriatus lives in forest areas and deserts, where it hides in small holes or under stones.

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Meanwhile, researchers from the University of Washington claim that the venom of this scorpion can be used in the fight against cancer.

Scientists have identified one of the poison's compounds, called chlorotoxin, which they believe may help deliver anti-cancer genes to glioma, an aggressive brain tumor that is usually fatal in humans. Chlorotoxin allows therapeutic anti-cancer genes to reach and kill more cancer cells than other approaches do.

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Scorpion is a very interesting and unusual creature that leads an exclusively terrestrial lifestyle in areas with a hot climate. Many often in relation to him may have questions such as: scorpion is an insect or animal where does it live, what does it eat and how does it reproduce. We will answer them in our article.

Features and habitat of the scorpion

Scorpion belongs to animals order of arthropods and class arachnids. It is distinguished by its rather intimidating appearance and speed of movement, and females and males are similar in appearance.

AT description appearance scorpion it should be noted that its body consists of a cephalothorax and an elongated segmented abdomen. The cephalothorax has a trapezoidal shape, on which there are pincers of impressive size, which serve to grab prey.

Also in the lower part of this section of the body (near the mouth) there is a pair of tentacles, which have become rudiments, performing the function of the jaw organs - the mandibles. The abdomen, in turn, contains outgrowths and four pairs of legs.

These outgrowths, with the help of the hairs on them, are the organs of touch. Various vibrations are captured by the hairs, which provide the animal with information about the terrain or the approach of the victim.

The limbs are attached to the bottom of the abdomen and allow the creature to develop very high speed when moving through areas with obstacles, in the form of quicksand in the desert or stones in the mountains.

The last segment of this part of the body of the scorpion ends in a relatively small pear-shaped segment-capsule containing glands that produce poison. At the end of this capsule is a sharp needle, with which this creature injects poison into the body of the victim.

The body of a scorpion is covered with a very strong chitinous shell, so it has almost no enemies that can harm it. In addition, it contains a substance that can glow when exposed to ultraviolet rays.

Depending on the habitat conditions, these creatures have a different color of the chitinous cover. So, there are sandy-yellow, brown, black, gray, purple, orange, green and even colorless scorpions.

The creature has rather poor eyesight, although it has many eyes. So, in the upper part of the cephalothorax there are 2–8 organs of vision, and two of them are larger and are called median.

The rest are located on the sides of the front edge of this part of the body and are called lateral. The lack of sight is fully compensated by the sense of touch, which is very sharp.

In nature, there are several types of scorpions, which differ in their size, color, habitat and life expectancy. They are imperial, arboreal, desert hairy, black and yellow fat-tailed and stripetdal.

The habitat of the scorpion is very wide, it can be found on almost all land areas with the exception of some areas of the Arctic, Antarctica and the New Zealand Islands, however, it prefers warm, arid regions, therefore it is often called scorpion desert animals.

The nature and lifestyle of a scorpion

Since this animal lives in arid zones, it is distinguished by its endurance to environmental conditions. He very easily tolerates heat, cold, hunger and even radiation.

To reduce body temperature, depending on the terrain, he buries himself in the ground or hides in stones, or cools himself in an interesting way, which consists in taking a stance, characterized by the fact that he straightens his legs to prevent contact of the body with the ground. This position allows free circulation of air, which cools the creature's body from all sides.

Important for life in such zones is the ability of the scorpion to go without liquid for several months. He easily makes up for her lack with the help of his victims. However, when the opportunity arises, he likes to drink water and bathe in dew.

Also, due to the special structure of the digestive system, the scorpion does not need regular nutrition. Although scorpion enough dangerous animal however, it has a peaceful character. When a person approaches, the creature prefers to take cover in nearby shelters, attacking only in extreme cases.

The creature hunts at night, learning about the approach of prey by the vibration caught by the hairs. In preparation for the attack, he takes a threatening posture, characterized by bending the tail and waving it in different directions. Scorpion mostly leads a solitary lifestyle, very rarely when they gather in groups, so he finds his mate by a lucky chance.

Scorpion food

Which same animal scorpion in terms of nutrition? The scorpion is a predator. His main food is insects (, centipedes,), however, he does not disdain small rodents, and cases of "cannibalism" are not uncommon in which weaker relatives are eaten.

During the hunt, the creature grabs prey with the help of pincers and pricks with a poisonous sting, first paralyzes it, and then kills it. As mentioned earlier, the creature does not feed every day.

Reproduction and lifespan of a scorpion

Having found a female, the male does not immediately mate with her. The couple preliminarily goes through the mating season, accompanied by the performance of the "wedding" dance by the scorpions, the duration of which takes hours. In time, the male, holding the female with the help of claws, moves her back and forth on the soil moistened with his sperm and periodically lowers it onto her.

After mating, in which the female often eats the male, she becomes pregnant, which lasts 10–12 months. Since the scorpion is a viviparous animal, this act of cannibalism provides a large number of nutrients necessary for producing strong offspring.

After this period, cubs appear, the number of which, depending on the variety, ranges from 20 to 40 pcs. For the first two weeks, babies do not have a chitinous shell, so they are all the time on the back of the female, clinging tightly to each other.

Pictured is a scorpion with cubs on its back

As soon as the shell is formed, the cubs leave the mother and scatter around the nearby territory for independent existence. To an adult, they grow only after a seven-fold molt.

The scorpion has a rather long life span, which under natural conditions can reach 7–13 years, however, in captivity, which they do not tolerate well, it is significantly reduced.

What to do with a scorpion sting?

For a person, a scorpion sting in most cases is not fatal, it mainly causes discomfort, accompanying such manifestations as sharp pain, swelling and redness of the skin around the wound. However, the poison of some species of these animals can be fatal.

Since not each of us can identify which scorpion has bitten - dangerous or non-dangerous, it is necessary to immediately provide first aid. To do this, you need to try to squeeze out or suck out the poison.

Treat the wound with antiseptic drugs, apply cold or apply a tight bandage that can slow the spread of the poison. Apply antiallergic agents. After providing first aid, be sure to take the victim to the hospital.

Despite the fact that the scorpion is quite dangerous, people have been interested in it since ancient times. Nowadays, it is increasingly possible to see it in people's homes, and it is also the main attribute in magic and witchcraft.

Scorpions are the oldest detachment not only among arachnids, but also among terrestrial arthropods in general. As noted, they represent the descendants of the Paleozoic eurypterids, and this is a rare example among arthropods, where the transition from an aquatic to a terrestrial way of life is quite fully traced from paleontological materials. Among the Silurian eurypterids, forms were found that are very similar to scorpions, but lived in water and breathed with the help of abdominal gill legs. In land scorpions, the latter have turned into lungs. The structure of walking legs has also changed. In aquatic forms, they ended in a pointed segment ( pointed-legged group- Apoxipodes), the terrestrial legs lengthened and their end parts turned into jointed paws adapted to walking on land ( two-claw group- Dionychopodes). Terrestrial forms, in general similar to modern scorpions, are already present in the deposits of the Carboniferous period.

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Scorpions are medium-sized or large forms, usually 5-10 cm, some up to 20. In appearance, large pedipalps with claws and a jointed flexible metasoma (“tail”) with a poisonous apparatus at the end are most characteristic. In structure, scorpions are closest to the prototype of chelicerae. Three parts of the body - pro-, meso- and metasoma - are well expressed, each consists of 6 segments. The cephalothoracic shield is entire, it has a pair of larger median eyes and up to 5 pairs of small lateral ones. Chelicerae are small, claw-shaped, pedipalps are very large with massive claws. The coxae of the pedipalps and the two front pairs of legs have chewing processes directed towards the mouth. The abdomen adjoins the cephalothorax with a wide base, the pregenital (7th) segment is atrophied. The anterior part of the abdomen (mesosoma) is wider, its segments have isolated tergites and sternites; modified abdominal limbs are represented by a complete set: genital opercula on the eighth segment, ridge-like organs on the ninth, lung sacs on the tenth to thirteenth. The segments of the posterior section (metasoma) are narrow cylindrical; the tergite and sternite of each segment are fused into a single sclerite ring; the first metasomal segment is conical. The metasoma ends with a swollen caudal segment; a poisonous gland is placed in it, the duct of which opens at the end of a curved sharp sting. The scutes of the trunk and segments of the extremities are formed by a very hard cuticle, often with a ribbed or tuberculate sculpture.

Scorpions live in countries with a warm or hot climate, and are found in a wide variety of habitats, from humid forests and littoral sea coasts to barren rocky areas and sandy deserts. Some species are found in the mountains at an altitude of 3 - 4 thousand meters above sea level. It is customary to distinguish between hygrophilous scorpion species living in humid areas and xerophilic scorpion species found in dry areas. But this division is largely arbitrary, since they are all active at night, and during the day they hide in shelters, under stones, under loose bark, in the burrows of other animals, or burrow into the soil, so that even in dry areas they find places where the air is sufficiently humid. . Differences in relation to temperature are more distinct. Most species are heat-loving, but some, living high in the mountains, as well as at the northern and southern borders of the scorpion range, tolerate cold winters well when inactive. Some species are found in caves, but they are random aliens here. Scorpions are frequent visitors to the dwelling of a person, but there are no real roommates of a person (synanthropes) among them.

The way of life of scorpions was studied by a number of researchers, we owe valuable information to Fabre. When kept in a perch, the habits of scorpions are distorted, and, as some authors note, there is no more freedom-loving creature than a scorpion.

Scorpions in captivity need a sufficient variety of conditions and the possibility of their free choice: a large cage area, different soil or sand moisture in different parts of it, the presence of shelters, periodic changes in light and temperature, etc. At the same time, the behavior of scorpions is close to natural, in In particular, the daily rhythm of activity is clearly expressed.

The scorpion comes out hunting at night and is especially active in hot weather. It walks slowly with its “tail” raised, with half-bent pedipalps forward with open claws. He moves by feeling, the main role is played by protruding tactile hairs (trichobothria) of the pedipalps. The scorpion is very sensitive to touching a moving object and either grabs it if it is a suitable prey, or retreats, taking a threatening posture: it abruptly bends the “tail” over the cephalothorax and swings it from side to side. The prey is seized by the claws of the pedipalps and brought to the chelicerae. If it is small, then it is immediately kneaded by chelicerae and the contents are absorbed. If the prey resists, the scorpion stings it one or more times, immobilizing and killing with poison. Scorpions feed on live prey, the objects of hunting are very diverse: spiders, haymakers, centipedes, various insects and their larvae, cases of eating small lizards and even mice are known. Scorpions can starve for a very long time, they can be kept without food for several months, there are cases of starvation up to a year and a half. Most species probably go their entire lives without water, but some tropical rainforest dwellers drink water. When kept together in small cages, a scorpion often eats a fellow.

The biology of reproduction is peculiar. Mating is preceded by a "nuptial walk". Male and female grapple with claws and, raising their “tails” vertically, walk together for many hours and even days. Usually the male, backing away, entails a more passive female. Then copulation takes place. At the same time, individuals hide in some kind of shelter, which the male, without releasing the female, quickly clears with the help of his legs and “tail”. Fertilization is spermatophoric. Individuals touch the ventral sides of the anterior abdomen, and the male inserts sperm bags into the female's genital tract, and then secretes a special secret that seals the female's genital opening. It is believed that when mating, scallops, the modified limbs of the ninth segment, play some role. They are equipped with numerous sense organs. At rest, the scallops are pressed to the abdomen; when mating, they protrude and oscillate. But they also bulge when the scorpion moves, and they are also credited with the role of organs of balance and some other functions.

Scorpions are mostly viviparous, some species lay eggs in which the embryos are already developed, so that juveniles soon hatch. This phenomenon is called ovoviviparity. The development of embryos in the mother's body is long; from a few months to a year or more. In some species, the eggs are rich in yolk and the embryos develop in the egg membranes, in others there is almost no yolk and the embryos soon emerge into the lumen of the ovary. As they grow, numerous swellings of the ovary are formed, in which the embryos are placed. They feed on the secretions of special glandular appendages of the ovary.

Embryos can be from 5-6 to several dozen, less often about a hundred. Baby scorpions are born wrapped in an embryonic membrane that sheds shortly after. They climb onto the mother's body and usually stay on it for 7-10 days. Scorpions of the first age do not actively feed, they are whitish, with a smooth cover and sparse hairs, the paws are devoid of claws and have suction cups at the end. Remaining on the body of the female, they molt, and after a while they leave the mother and begin to search for food on their own. After molting, the integuments harden and stain, claws appear on the paws. A scorpion becomes an adult a year and a half after birth, making 7 molts during this time. Life expectancy has not been precisely established, but it is usually at least several years. There are interesting cases of anomalies that occur in the embryonic development of scorpions, for example, the doubling of the “tail”, and the individuals are viable and grow to adulthood (“two-tailed scorpion” is mentioned by the already famous Roman scientist Pliny the Elder in his “Natural History”, 1st century AD e. .).

Hard covers and a poisonous apparatus do not always save scorpions from enemies. Large predatory centipedes, salpugs, some spiders, praying mantises, lizards, and birds cope with them. There are species of monkeys that feast on scorpions, carefully removing the "tail". But the worst enemy of scorpions is man. Since ancient times, the scorpion has been the subject of disgust and mystical horror, and, perhaps, there is no other arthropod that would give rise to so many tales and legends. Scorpio appears both in the ancient myths of the Egyptians and Greeks, and in the prescriptions of medieval alchemists as a magical attribute of the "transformation" of lead into gold, and in astrology, since one of the zodiac constellations bears the name of the scorpion, and among Christians as a typical component of the "fauna" of the underworld. Curious are the assurances that scorpions can end their lives with “suicide”: if you surround a scorpion with burning coals, then in order to avoid a painful death, it seems to kill itself with a sting. This opinion is not true, but has a well-known basis. The fact is that the scorpion, like some other arthropods, under the influence of strong stimuli, can fall into a motionless state - a phenomenon of imaginary death (catalepsy, or thanatosis). Being surrounded by burning coals, the scorpion, of course, rushes about in search of a way out, assumes a threatening posture, waves its “tail”, and then suddenly becomes motionless. This picture is taken for "suicide". But after some time, such a scorpion "comes to life", unless it is baked from the heat. Equally unreasonable is the rather widespread belief that a scorpion specifically seeks out a sleeping person at night to sting him. Where there are many scorpions, on hot nights, making their hunting walks, they often visit dwellings and can even climb onto the bed. If a sleeping person crushes a scorpion or touches it, then the scorpion can strike with its “tail”, but, of course, there are no special searches for a person here.

A scorpion sting is a means of attack and defense. On small invertebrates, which usually serve as food for a scorpion, the poison acts almost instantly: the animal immediately stops moving. But the larger centipedes and insects do not die immediately and live for a day or two after the injection; there are also insects that, apparently, are generally insensitive to the venom of scorpions. For small mammals, scorpion venom is mostly fatal. The poisonousness of different types of scorpions is very different. For a person, a scorpion sting is usually not fatal, but a number of cases are known with very serious consequences, even fatal, especially in children and in hot climates. When injected, pain, swelling appear, then drowsiness, chills, and sometimes a temperature reaction occur. Usually after a day or two these phenomena pass, but they can be delayed. It all depends on which scorpion pricked, whom and where. In our country, most cases of scorpion stings are observed in Central Asia and Transcaucasia, where scorpions are common and numerous.

About 600 species of scorpions are known, belonging to about 70 genera and 6 families. The geographical distribution of scorpions is of great interest for zoogeography - the science of the patterns of distribution of animals. Being the oldest terrestrial arthropods, scorpions reflect in their distribution the geological and climatic changes and the change of plant and animal communities that have occurred many times in the history of the Earth. The limited ability of scorpions to settle makes this data particularly valuable: in most cases, certain forms are present where they have managed to survive from ancient times.

The works of a number of scientists are devoted to the development of classification and the study of the distribution of scorpions. Very valuable are the studies of A. A. Byalynitsky-Biruli, who in his work on the scorpions of the Caucasus (1917) made a remarkable analysis of materials on the distribution and evolution of scorpions in general. At present, the area of ​​\u200b\u200bdistribution of scorpions encircles the globe between about 50 ° north and south latitude, but in past eras, up to the end of the Tertiary period, when the climate was warmer and humid forests extended to high latitudes, scorpions were found on most of the land.

According to morphological features, scorpions fall into two large groups: butoids represented by the Buthidae family (up to 300 species), and hacktoids(other families). It is believed that these groups separated in remote times, probably already in the Silurian period, and since then each has evolved in its own way, in its own way reflecting the phenomena that influenced the distribution of fauna (separation of the continents, climate change, etc.). The distribution of primitive representatives of these groups confirms the data of geology that the world's land for a long time (from the beginning of the Paleozoic until the first half of the Cenozoic era) was divided by seas into two sets of continents - northern and southern. So, the ancient subfamily of butoids - Isometrinae - is distributed mainly in Africa and South America, and for South America and at the same time Australia, a peculiar family Bothriuridae is characteristic. Ancient hacktoid scorpions of the families Chactidae and Vejovidae are confined to the subtropical zone of the northern hemisphere in the Old and New Worlds and are completely absent in Africa and Australia.

The general picture of the modern distribution of scorpions is the result of a complex stratification of faunistic elements of different eras and, on the whole, confirms the division of land into zoogeographic regions, established on the basis of the distribution of animals in general. In the Buthidae family, subfamilies, and often even genera, are strictly confined to certain zoogeographic regions, i.e., they have a high degree of endemism. Thus, the subfamilies Centrurinae and Tityinae inhabit the North and Central American regions of the Neotropical region. The genera Parabuthus and Babycurus from the subfamily Buthinae are characteristic of the Ethiopian region of Africa (south of the Sahara); the genus Grosphus is found only in Madagascar. Many genera live along the borders of deserts from the Atlantic Ocean to India, representing Sahara-Indian faunal elements. The genera Isometrus and Isometroides are characteristic of the Australian fauna. Among hacktoid scorpions, lodfamilies and entire families have a high degree of endemism. The family Scorpionidae is mainly represented by Ethiopian forms, the Madagascar genus Heteroscorpius, and the Indo-Malayan Heterometrus. In the family Chactidae, as mentioned, there are no Ethiopian species, the subfamily Chactinae is neotropical, Cherilinae is Indo-Malayan, Scorpioninae is Mediterranean. The distribution of subfamilies of the family Vejovidae is similar. The family Bothriuridae is mainly South American, but there are species living in Australia and Sumatra. The fauna of India is especially rich in scorpions, where there are over 80 species. There are about 100 species in the fauna of the Palearctic, of which about 15 are found in the USSR.

In Transcaucasia, the Lower Volga region and throughout Central Asia, it is common motley scorpion(Buthus eupeus), forming a number of subspecies. It is brown-yellow with dark spots and longitudinal stripes on the back, up to 6.5 mm long. In Crimea, especially on the southern coast, it is not rare Crimean scorpion(Euscorpius tauricus), characteristic only of the Crimea. It is light yellow, claws are narrow, brownish, 35-40 mm long. Common in Western Transcaucasia mingrelian scorpion(E. mingjelicus), reddish brown, lighter below, up to 40 mm long. On the Black Sea coast of the Caucasus still lives italian scorpion(E. italicus), red-brown or almost black, up to 55 mm long.

Animal life: in 6 volumes. - M.: Enlightenment. Edited by professors N.A. Gladkov, A.V. Mikheev. 1970 .

Unusual things we learned about animals in 2013. Incredible Facts

Like any other year, 2013 had its ups and downs, surprises and disappointments, but overall it was a great year for zoology.

The researchers found a new creature they called the olinguito, figured out that crickets have a "turn off" feature, and learned why bees sense the electric fields created by flowers.

What other important discoveries have been made?

New facts from the life of animals

Grasshopper hamsters are resistant to scorpion venom

There are mice and there are grasshopper hamsters. While an ordinary mouse gnaws seeds and is a little cowardly at the same time, a grasshopper hamster is an insane serial killer. Unlike most rodents, these guys are very fond of meat.

They prey on lizards, insects, arachnids, as well as other mice, and before killing their prey, they rear up and howl terrifyingly.

In 2013, scientists discovered another reason little creatures should be afraid of the grasshopper hamster. They are not susceptible to scorpion venom.

The scorpion stings very painfully.

A one-on-one meeting with a scorpion for many mammals can end very unpleasantly, if not tragically. But not for the southern grasshopper hamster (Onychomys torridus) - for him this arthropod is just food.

You should not lose your vigilance, because behind the harmless name and modest size (the body length of the rodent is only 9-13 centimeters), a real carnivorous monster is hiding. Its diet consists mainly of beetles, spiders (including tarantulas), grasshoppers, woodlice and scorpions.

However, on occasion, these hamsters kill and eat mice, some types of rats and lizards. And in especially difficult times, rodents show a tendency to cannibalism (eating representatives of their own species).

Grasshopper hamsters are extremely aggressive, which cannot be said about other rodents. For example, O. torridus are not accustomed to building their own nests, instead they prefer to appropriate someone else's home, using brute force if necessary.

Arizona tree scorpion (Centruroides sculpturatus) (photo by Brian Basgen).

Probably, these same natural qualities help hamsters deal with dangerous opponents, for example, with the Arizona tree scorpion (Centruroidess culpturatus).

It is worth recalling here that scorpion venom contains strong neurotoxins that specifically act on nerve cells. Damage to the nervous tissue occurs due to the interaction of neurotoxins with membrane proteins, which ultimately leads to an imbalance in the ionic balance in the cell. Being absorbed into the blood, the poison causes a long-term overexcitation of the nervous system. The result of a scorpion sting can be local pain and swelling, nausea, vomiting, convulsions, muscle spasms and much more, up to paralysis and respiratory arrest.

In a battle with a scorpion, rodents receive many punctures from arthropods, but their venom does not harm the grasshopper hamster.

photo Roger W. Barbour

Grasshopper or scorpion hamsters are very difficult creatures. These little furry rodents feel almost no pain. Hunting and further eating of scorpions is a common thing for them.

When a hamster pounces on a poisonous arthropod, it barely feels its painful bite, and the poison has practically no effect on it.

Ashlee Rowe from the University of Michigan wondered how a hamster regularly eats these terrible creatures and does not die.

Intrigued, she injected scorpion venom into the hind legs of these wild mice, and for comparison and contrast, she did the same with a group of normal "domestic" mice. After the injection, normal mice licked their wound for about four minutes and died, while the wild mouse spent only a few seconds and was ready to hunt again.

Next, the researchers injected the mice with a formalin solution. The normal mouse started in extreme pain, while these "little guys just shrugged". Does this mean that grasshopper hamsters are immune to everything?

Apparently - yes, because they do not even react to poison. Usually, when a venomous creature stings a rodent, the toxins enter the sodium channels of the hamster's nerve cells. Thus, sodium spreads through the cells and sends a signal to the brain about severe pain.

However, the specimen is so strong that a special channel blocks the flow of sodium, which actually turns the poison into a painkiller. That is why these mice were not harmed by either the poison or the caustic injection of formalin.

Now scientists have uncovered the secret of desperate rodents: they found a mutation in a protein that controls the pain response.

Lead author Ashley Rowe and colleagues continued their study of nerve cells in O. Torridus. It turned out that, just like in ordinary mice, neurotoxins cause mutations in them. However, their target is another membrane protein that is not involved in the transmission of pain sensations to the brain. That is, it turns out that grasshopper hamsters are simply immune to scorpion venom.

The researchers calculated a molecular pathway in neurons that is different in grasshopper hamsters from other animals. The focus was on two sodium channels responsible for the transmission of pain signals in mammals. One of them produces a signal, and the other propagates it. Humans have a rare mutation in the spreading duct that manifests as congenital pain insensitivity syndrome with anhidrosis (CIPA).

Scorpion venom stimulates the activity of the initiation channel (the one that produces the signal) in grasshopper hamsters, but almost completely blocks the activity of the spreading channel. Thus, pain simply does not occur.

Rowe and her colleagues realized that the difference between the sodium channels of sensitive mice and non-painful hamsters must be structural. As it turned out, in grasshopper hamsters, the protein that determines the operation of the sodium channel differs from the mouse one by only one amino acid. It is this feature that is responsible for blocking the activity of the propagating channel.

"I understand that there may be other factors influencing this feature, but the extra amino acid in the protein is key," Rowe said in a press release.

The resistance of grasshopper hamsters to poison is evolutionarily determined. Unlike many other members of their family, they had to survive in rather harsh desert conditions in the southwestern United States. These territories are teeming with scorpions, but there were very few other, less dangerous inhabitants that hamsters could eat.

At this stage, the study of this mechanism is fundamental, but in the future it will be useful in the development of a new generation of painkillers. The results of the work of Rowe and her colleagues were presented in an article published in the journal Science.

More than a million people suffer from scorpion stings every year, scientists say, about three thousand cases end in death.

Not surprisingly, researchers are seizing every opportunity to investigate the mechanisms of natural resistance to neurotoxins in the wild in order to develop based on these data both an effective antidote and other drugs, for example, to combat pain.

The consequences of this discovery could be very serious, because pharmaceutical companies finally have a chance to figure out how to block sodium channels in the human body.

Someday, we can all become superhumans, immune to pain, thanks to these powerful rodents.

Used sources.