What genus do spiders belong to? Regular spider. Is a spider an insect or not? Main differences. Structural features and description of species

The first spiders appeared about 400 million years ago. They descended from a crab-like ancestor. To date, there are more than 40 thousand species of spiders.

Many people believe that spiders are insects. In fact, spiders are a separate order and class - arachnids (Arachnida, subtype Cheliceraceae - Chelicerata, type Arthropods). Markedly different from insects.

First of all, it is worth noting that spiders do not have 6 legs, but 8. In front there are special limbs with poisonous claws - chelicerae. However, in Central Russia, the presence of deadly spiders for humans has not been registered. From a big bite
a spider can be felt except for burning, fever and pain. The first spiders will not attack. If a medium-sized spider accidentally falls from the web onto a person, then you should carefully blow it off, and not beat it - otherwise it may get scared and bite.

Spiders usually have three pairs of spider warts on their abdomens. Digestion in these arthropods is extraintestinal. Unlike, for example, predatory praying mantises, which chew the caught fly with appetite, the spider injects digestive enzymes into it, which turn
the insect into the "soup" after a few hours, after which it sucks out the contents. Spiders have a very strong web, if an airplane crashes into a pencil-thick web, it will not break.

Spiders usually have 8 eyes, sometimes 6, or very rarely 2. Males have bulbs on their forelimbs, into which they place sperm to fertilize the female. Some males are already prepared in advance for death after mating - they allow the female to eat themselves, others intend to fight for their lives and seek to escape. In any case, males do not live long, but females need to raise offspring, so they live longer. Males are smaller, females are huge. Many females are caring mothers. They weave a ball-cocoon from a web and carry spiders in it.

Almost all spiders are predators. The exception is Kipling's Bagheera spider (Bagheera kiplingi). Biologists discovered this jumping spider in the forests of Central America, on the branches of an acacia tree. Spiders live on acacia along with ants. Ants guard these trees for Belt's nutrient corpuscles (named after the naturalist Thomas Belt), sweet shoots at the ends of the leaves. tropical species acacias. Spiders also feed on these formations.

The first thing that catches your eye when meeting insects is their long constantly moving whiskers (antennas). Spiders do not have antennae. Their eyes are also simpler, but there are many of them - most often eight. The body is covered with an external skeleton (exoskeleton). It consists of a cephalothorax and abdomen, connected by a stalk.

Krinitsyn Oleg

When I was little, I was very afraid of spiders - I ran away and hid from them. And when I grew up, I decided to learn more about them so as not to be afraid, and maybe even make friends with these mysterious creatures.

In the summer I visited my grandmother in the village, I had the opportunity to follow the spiders. I even overcame my fear and began to pick them up and see how they behave. It was very interesting. Adults knew a little about the life of spiders, so I began to look for material in books. I was able to learn a lot of interesting things about these amazing animals from encyclopedias. I was very interested to know: how many species of spiders exist; what species are the spiders I observed; how they differ from each other; what do they eat; how they move on walls and ceilings. Also, I wanted to find the answer to the question: “Where do they get the web from?” And I also wanted to figure out why the spider is not an insect, because they are so similar. Many consider them nasty, dangerous, disgusting. Therefore, I would like to change my mind about spiders, to tell adults, classmates, why spiders are interesting and useful.

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Department of Education

Administration of the municipality

Nadymsky district

Municipal educational institution

"Secondary school No. 6
with in-depth study individual items» Nadym

Research

Krinitsyn Oleg,

2nd grade student.

Pedagogical leader:

Katyukova Olga Viktorovna,

primary school teacher.

Nadym

2013

I.Introduction

Of the creatures that live near us, spiders are without a doubt the most interesting ... Karl Frisch

When I was little, I was very afraid of spiders - I ran away and hid from them. And when I grew up, I decided to learn more about them so as not to be afraid, and maybe even make friends with these mysterious creatures.

In the summer I visited my grandmother in the village, I had the opportunity to follow the spiders. I even overcame my fear and began to pick them up and see how they behave. It was very interesting. Adults knew a little about the life of spiders, so I began to look for material in books. I was able to learn a lot of interesting things about these amazing animals from encyclopedias. I was very interested to know: how many species of spiders exist; what species are the spiders I observed; how they differ from each other; what do they eat; how they move on walls and ceilings. Also, I wanted to find the answer to the question: “Where do they get the web from?” And I also wanted to figure out why the spider is not an insect, because they are so similar. Many consider them nasty, dangerous, disgusting. Therefore, I would like to change my mind about spiders, to tell adults, classmates, why spiders are interesting and useful.

Purpose of the study:explore external structure spiders, find differences between spiders and insects, make sure spiders are not insects.

Tasks:

• to study the literature on the topic of research work;
• compare spiders and insects;
• find out what kind of spiders live at my grandmother's house and in the garden;
• observe their lives
• present the work to the children.

Hypothesis: spiders do not have signs of insects, they are not insects

I have determined the ways and methods of research:

• study of sources of information;
• observation;
• conversation;
• analysis;
• practical work.

Object of study: spiders.

Subject of study: spider life.

II.Main part

2.1. Who are spiders?

From the encyclopedia, I learned that spiders are the largest order of arachnids. Spiders (lat. Aranei ). 35,000 species have been described, and this number should rise to about 50,000, since all spiders have not yet been studied.

Spiders on Earth appeared so long ago that it’s even hard to imagine (approximately three hundred and fifty million years ago), the ancestors of spiders first climbed onto land from the water in which the entire animal world lived in those distant times.

Spiders appeared a hundred million years before flying insects, and when people appeared, spiders already felt like masters and looked like they do today.

Spiders are currently one of the thriving animal groups. It is difficult to find a place in nature where spiders would not live. They mastered everything natural areas Lands from deserts and tropical forests to the islands of Antarctica. The conquerors of Everest found a spider at an altitude of 7,000 meters. Spiders survive where other animals die, such as in the highlands and in caves. Spiders are very hardy and interesting animals.

All spiders are predators, but since they do not have good eyesight, they lie in wait for their prey. Spiders catch their prey on the web or by other means. Spiders that catch their prey with their webs are called web spiders. With the help of the chylecera, the spider injects poison into the victim. After several hours, the prey turns into a thick mass and the spider “drinks” it. Yes, yes, it is “drinking”. Spiders eat only liquid food. They suck out the victim, leaving a dry shell from it. Even such giants as the bird spider "drink" their victims, as if through a straw. Moreover, their menu includes not only insects, but even lizards and birds. Sometimes they eat each other.

However, there are spiders that do not use webs for hunting. They catch up with prey by jumping, waiting in ambush, etc. The victim of a hunter can be: frogs, small rodents, insects ...

Spiders, scorpions and ticks are similar to each other, so they are classified as arachnids. Spiders are close to insects in a number of ways, but they clearly differ from them, and these groups are connected only by a very distant relationship.

2.2 Why a spider is not an insect

In order to figure out whether a spider is an insect or not, I decided to study and compare the structure of a spider with the structure of insects.

I learned that spiders have 2 body parts: cephalothorax and abdomen. Spiders have 4 pairs of legs and pedipalps are very similar to legs. The bases of the pedipalps are transformed into chewing organs.

Spiders have up to 8 simple eyes. Despite this a large number of organs of vision, many arachnids see very poorly. So bad that this distance is on average 30 cm.

Spiders do not have a skeleton inside the body. They have a hard outer shell called an "exoskeleton". As the spider grows, it is necessary to shed the old tight shell. When molting, the spider climbs out of the old body and waits for its new delicate skin to dry and harden. At the moment of molting, spiders are especially vulnerable.

At the end of the abdomen are arachnoid warts. The substance coming out of them hardens and turns into threads of extraordinary strength.

Insects, Insecta - a class of creatures with no vertebrae and jointed legs. They differ in body structure (divided into 3 sections - head, breast and abdomen), one pair of antennae, 3 pairs of legs on the chest and mainly 2 pairs of wings. Some insects through special bodies secrete various substances: cobwebs, silk, wax, poisons. The skin of insects is formed mainly from chitin, which forms a strong outer skeleton. The cavities are filled with the so-called fat body.

Insects have two eyes. They feed on plant and animal products. Insects in a colossal number of species inhabit the earth. Appeared in the distant geological periods(starting with coal). About 10,000 species are known in the fossil state.

Thus, we can conclude: spiders are not insects. They belong to the class of arachnids, and differ from insects primarily in the structure of the body. The body of the spider consists of the cephalothorax and abdomen, breathing is carried out by lung sacs and tracheae. In insects, the body is divided into the head, chest and abdomen, and they breathe exclusively through the trachea. In addition, the spider has 4 pairs of legs, in turn, insects are arthropods that have 3 pairs of legs and 2 pairs of wings . Also, an insect can be distinguished from a spider by the presence of antennae, while spiders do not have antennae.

comparison table

"What is the difference between spiders and insects"

2.3 Interesting facts about spiders

It should be noted that spiders, especially tarantulas, have a certain amount of intelligence, they can even distinguish between their own and others. It is these spiders that are often used as pets. They are also very subtle and feel the mood of their own master, and therefore you can even play with them, they are even able to protect their own master if he is in danger, and they can also dance to the music.

Spiders of the species Cyclosa mulmeinensis from Singapore are able to make a copy of themselves from the garbage and remains of victims that have fallen into the network. The model has "legs" and reflects light like its prototype, and a breath of wind can give the impression that it is moving. Thus, these spiders deceive the wasps that hunt them, since the dummy is located in the most prominent place of the web, and in most cases predators attack it, allowing the real spider to hide.

Spiders of the genus Cyclocosmia, living in Asia and North America, have an original appearance: their abdomen ends with a hard surface in the form of a disk, on which numerous grooves form an intricate pattern. In the species Cyclocosmia truncata, for example, this pattern resembles a seal. When this spider is threatened, it crawls into its hole and plugs the entrance with its disk, which matches the diameter of the entrance hole.

Spiders of the Theridion grallator species, which live only on the Hawaiian Islands, have an amazing body color that resembles a smiling human face, and the color of each individual is unique. Presumably, such a pattern should scare away their only enemies, birds.

It is possible to sew clothes from cobwebs, only it is several orders of magnitude more difficult and more expensive than from ordinary silk obtained from the silkworm. The first documented mention of such clothes dates back to 1710, when the French scientist and businessman de Seux Hiler made gloves and socks from "spider silk" and presented them to King Louis XIV. More recently, the American Museum of Natural History exhibited a piece of cloth a little over 3 square meters. To obtain it, several dozen workers caught golden spiders in Madagascar for 4 years, then carefully removed the threads from them and released them back into nature.

The web has a huge strength potential. A pencil-thin thread made from their web could stop a Boeing at full speed. IN this moment ultralight and durable bulletproof vests using webs are being developed.

2.4 Spiders that I watched in the summer in the village

At my grandmother's in the village, I watched the haymaker and funnel spiders.

2.4.1 Spider - Harvester

Harvester - we all know this amazing creature from the arachnid family with very long legs. If you grab a haymaker by the leg, it will easily come off and will twitch convulsively for many minutes. It is because of this movement, similar to the movement of a scythe, that the well-known names "spider-mow-hay" or "haymaker" arose.

The leg of the harvestman comes off with such ease that one gets the impression that it is very loosely attached to the body. Actually it is not. The kicking off of the leg is voluntary and depends on a specific muscular movement. This phenomenon is called autotomy - self-mutilation. The autotomy of the legs in the haymaker, like the autotomy of the tail in lizards, serves to save oneself from enemies. Approaching its prey, the predator first of all stumbles upon the palisade of limbs, and the torn off and twitching leg distracts it from the haymaker fleeing on the remaining legs. Therefore, it is often possible to meet harvestmen with an “incomplete” set of legs.

We will never see a haymaker weaving a web, arranging a lair for himself, or descending on a thin web thread - these arthropods do not have spider warts.

You can meet harvestmen on a tree trunk or on a fence, on a house wall or in cracks in the bark, under stones and in bedding in a forest, garden, park, field, or vegetable garden. Deciduous and mixed forests. In mountainous areas, these animals are found on rocks, in placers of stones and caves.

Harvestmen go hunting at dusk or at night. They feed on insects, small spiders and other invertebrates.The most big threat spiders are the spiders themselves. In the event of a hunger strike, they even kill their own offspring.

In the village of my grandmother, I managed to observe such a story. I planted two harvestmen in a plastic cup and fed them flies. But for a while I forgot about them and did not feed them, and two days later I discovered that there was one living spider in the glass - which is larger, and the other was eaten.

2.4 Funnel spiders

Perhaps one of the most famous spiders in Russia. He really likes to settle in houses and households. buildings. Usually weaves its net somewhere in the corner on the ceiling or behind the closet. In general, where the hostess's broom does not reach him. If it reaches it, the spider will not be upset: by the next morning, it will mockingly build a new web in another corner. In the middle of the web of a house spider there is always a funnel that leads to a small hole - his home. Here he sits and waits for prey - flying insects. As soon as someone touches the web, the owner jumps out of his hiding place and instantly cracks down on the troublemaker. There is usually a lot of dust in a person’s home, so the web becomes dirty very soon. It is his web that sticks to the ceiling and constantly sways.

The male grows up to 10 mm (excluding the length of the legs), the color is yellow-gray with brown spots. The female is larger, the color is the same as the male. Sometimes, if there is a lot of food, they grow to an impressive size and at times crawl along the walls, frightening children and women.

The spider is shy and never attacks people. However, he can still bite if you accidentally crush him. However, the poison is not at all dangerous to humans, it does not cause any visible consequences. The house spider is useful, as it exterminates various insects harmful to people right in the apartment: flies, mosquitoes and various moths.

And I also learned a very interesting fact: if at home you play on musical instruments, then the spider will come out to listen to you from the mink, or even begin to "dance" on its web. It turns out that the point here is not at all the musical preferences of spiders. Music vibrates the web like small insects, and the spider, in anticipation of dinner, comes out to visit: "who is shaking my web there?". Not finding anyone, he is probably very surprised and looks on for a while, puzzled. And then he even tries to "shake off" an invisible insect from the web.

Funnel spiders, by the way, are very sensitive to changes in temperature and humidity. Therefore, they can serve as a kind of living barometers. Previously, house spiders were completely trusted in such matters.

III. Conclusion

Some people are disgusted by or afraid of spiders. Often this is due to the fact that we know very little about these octopuses. However, only a small number of spider species are dangerous to humans, and they do not live in Europe. Spiders are not insects, as many people think, they feed on them. Many spiders weave webs that catch their prey. And this makes spiders useful to humans: they free us from flies, mosquitoes and other insects that often bother us. Without spiders, we would, if I may say so, "get bogged down" in insects.

Exploring the life of spiders, I learned a lot of interesting things, read various literature about the life of animals and came to the following conclusion:

Spiders are not insects.

The life of spiders is very interesting.

There are different kinds of spiders living near us.

The spider obtains its livelihood with the help of the web.

Spiders - predict the weather, they are experts in weather changes.

The spider is man's best friend!

In the future, I intend to study the life of these interesting animals even more deeply. And I will definitely share my knowledge and observations with my classmates, telling them about the amazing and diverse world of spiders and their benefits to humans.

Bibliography

1. "Mysteries of the Wild"; Moscow "ROSMEN", 2004
2. "My first book about animals"; Moscow "ROSMEN", 2006
3. "Around the world"; A. Tikhonov, Moscow "Bustard plus" 2008 https://accounts.google.com
   

   Slides captions:

   Why is a spider not an insect? Of the creatures that live next to us, spiders are without a doubt the most interesting ... (Karl Frisch) Prepared by Oleg Krinitsyn

   Foreword When I was little, I was very afraid of spiders - I ran and hid from them. And when I grew up, I decided to learn more about them so as not to be afraid, and maybe even make friends with these mysterious creatures. In the summer I visited my grandmother in the village, I had the opportunity to follow the spiders. I even overcame my fear and began to pick them up and see how they behave.

   Who are spiders? Spiders appeared on Earth a very long time ago, about three hundred and fifty million years ago, earlier than flying insects, and when people appeared, spiders already felt like masters and looked the same as they do today. It is difficult to find a place in nature where spiders would not live. Spiders survive where other animals die, such as in the highlands and in caves.

   Who are spiders? All spiders are predators, but since they do not have good eyesight, they lie in wait for their prey. Spiders catch prey on the web. They inject poison into their prey. After several hours, the prey turns into a thick mass and the spider “drinks” it. Yes, yes, it is “drinking”. Spiders eat only liquid food.

   Why a spider is not an insect Spiders are close to insects in a number of ways. In order to figure out whether a spider is an insect or not, I decided to study and compare the structure of a spider with the structure of insects. The body of the spider consists of the cephalothorax and abdomen, breathing is carried out by lung sacs and tracheae. In insects, the body is divided into the head, chest and abdomen, and they breathe exclusively through the trachea.

   Why a spider is not an insect In addition, the spider has 4 pairs of legs, in turn, insects are arthropods that have 3 pairs of legs and 2 pairs of wings. Spiders have up to 8 simple eyes. But despite this, they see very poorly. This distance is on average 30 cm. Insects have two eyes. Also, an insect can be distinguished from a spider by the presence of antennae, while spiders do not have antennae. Thus, we can conclude: spiders are not insects.

   Interesting facts about spiders Interestingly, spiders, especially tarantulas, have a certain amount of intelligence, they can even distinguish between their own and others. It is these spiders that are often used as pets. They also feel the mood of their master very subtly, and therefore you can even play with them, they are even able to protect their master if he is in danger.

   Interesting Spider Facts Spiders of the species Cyclosa mulmeinensis from Singapore are able to make a copy of themselves from garbage caught in the net. Thus, these spiders deceive the wasps that hunt them.

   Interesting facts about spiders Spiders that live only on the Hawaiian Islands have an amazing body color that resembles a smiling human face, and the color of each individual is unique. Presumably, such a pattern should scare away their only enemies, birds.

   Watching Spiders At my grandmother's village, I watched the haymaker and funnel spiders.

   Harvester You can meet harvestmen on a tree trunk or on a fence, on the wall of a house or in cracks in the bark, under stones. Harvester never weaves a web - they do not have spider warts. If you grab a haymaker by his long leg, it will easily come off and will convulsively twitch for many minutes. It is because of this movement, similar to the movement of a spit, that the name “haymaker” arose.

   Harvestman Harvestmen go hunting at dusk or at night. They feed on insects and small spiders. But sometimes they eat each other. In my grandmother's village, I put two haymakers in a plastic cup and fed them flies. Then I forgot about them and didn't feed them, and two days later I discovered that there was one live spider in the glass - which is bigger, and the other was eaten.

   Funnel spider The funnel spider is one of the most famous spiders in Russia. Likes to stay in houses. Usually weaves its net somewhere in the corner on the ceiling or behind the closet. In the middle of the web there is always a funnel that leads to a small hole - his home. If someone touches the web, the spider jumps out of its hiding place and instantly grabs the troublemaker.

   Video Feeding the funnel spider

   Conclusion The spider is shy and never attacks people. However, he can still bite if you accidentally crush him. However, the poison is not at all dangerous to humans, it does not cause any visible consequences. The house spider is useful, as it exterminates various insects harmful to people right in the apartment: flies, mosquitoes and various moths. Some people are disgusted by or afraid of spiders. Often this is due to the fact that we know very little about these octopuses. Exploring the life of spiders, I learned a lot of interesting things, and came to the main conclusion: The spider is a friend of man!

Spiders in Latin Araneae, Aranei. They belong to the animal kingdom, the type of arthropods, the class of arachnids. There are 42 thousand modern ones in the world, about 1.1 thousand fossils. They are ubiquitous and inhabit almost all continents of the world. Obligate predators - feed on insects, small animals, amphibians. The exception is Bagheera kiplingi, whose diet is the green part of the acacia. On the territory of Russia, the former CIS countries, there are 2888 species. The science of spiders is called arachnology.

What kingdom do spiders belong to?

Small creatures that are often seen in wild nature, their own house, apartment, attics, outbuildings, resemble all sorts of insects, beetles. Often spiders and insects are combined into one family due to their small size, similar lifestyle. However, in tropical countries. where arthropods up to 35 cm in size live, such associations practically do not occur.

There are 5 kingdoms in total - animals, plants, fungi, bacteria and viruses. Historically, spiders and insects belong to the same kingdom, type - animals, arthropods. Only the class or unit differs. Therefore, the question of who a spider is - an animal or an insect, is fundamentally wrong. Animal is a kingdom, insects are a class.

On a note!

Since everyone has long been accustomed to the fact that insects are insects, and animals are full-fledged mammals, there was confusion in the concepts of ordinary people. Why the spider stands apart is explained by its unusual way of life, small size. In order not to seem uneducated, you need to understand for sure that a spider is not an insect.

What class do spiders belong to?

In this case, there is no confusion in concepts, since the class has a consonant name - arachnids. A total of 42,000 are known. modern species, 1.1 thousand fossils. In all animals, the body is divided into 2 parts - the abdomen, the cephalothorax.

Main external difference from insects is - 8 legs instead of 6. Arachnids also have chelicerae located in front of the cephalothorax, tentacle-like pelipalps. They are located on the sides, differ somewhat in length from the forelimbs, perform similar functions - they help to move, hold the victim.

On a note!

The question is often asked - to which family do spiders belong, to which group of animals. These are arachnids, arthropods.

Species and orders

It is very easy to answer the question of which order spiders belong to. To a detachment with the same name - spiders. They stand apart. They differ from other animals in their way of life, size, reproduction, and nutrition. There are differences among themselves in the same family, depending on which species the spiders belong to.

General characteristics:

• The body consists of 2 parts - the cephalothorax, the abdomen is oval, round in shape.
• Only 4 pairs of legs, a pair of chelicerae, pelipalps.
• There are no antennae, but the forelimbs can be claw-shaped, ending in claws.
• Distinguishes arachnids from insects. Not everyone weaves trapping nets, but they use threads of their own production to form a cocoon, move down, migrate over long distances.
• Predators have poison glands that paralyze their prey. Turn the insides into a liquid mass.
• Unlike insects, they rarely live in pairs, in a large family. All spiders lead a solitary lifestyle. In some species, young spiders live with their mother until they get stronger. Almost all females eat males after fertilization or in the near future.

Arachnids live everywhere, some of them are human, apartment, settle in utility rooms. Exotic, kept as a pet.

At the exclamation of "spider", most people will cringe, because they do not associate this word with anything good. The first thing that comes to mind is that spiders are poisonous, and non-poisonous ones are just unpleasant ... they look so strange, and they weave webs in the corners. But one has only to get to know these creatures better and fear will be replaced, if not with delight, then with respect. Few can compare with them in terms of diversity of structure, lifestyle and complexity of behavior. From the point of view of taxonomy, spiders make up a separate order of the class Arachnida, numbering 46,000 species! And this is not a complete list, because new types of spiders continue to be discovered until now. Their closest relatives are ticks, salpugs and scorpions, and their distant ancestors are marine arthropods like relic horseshoe crabs. But with insects, to which spiders are often ranked, they just have nothing in common.

The two-horned spider (Caerostris sexcuspidata), which lives in the arid regions of Africa, imitates a dry tree with the help of body shape, color and posture.

The body of spiders consists of a cephalothorax and abdomen, connected by a so-called stalk. The cephalothorax is usually small, and the abdomen is highly extensible, therefore, in size significantly more breasts. In most species, the stem is so short that it is almost invisible, but myrmecium spiders, mimicking ants, boast a thin waist.

A spider from the genus myrmecium (Myrmecium sp.) pretends to be an ant, but its cunning is easy to unravel if you count the number of legs.

All spiders have eight legs, and by this feature they can be unmistakably distinguished from insects, which have six. But besides the legs, spiders have several more pairs of limbs. The first, called chelicerae, is located near the mouth. According to their purpose, chelicerae are a cross between mandibles and hands. With their help, spiders grab and cut prey, and also hold the female during mating, cut the web - in a word, they perform delicate types of work. The second pair of limbs are pedipalps. They are also located on the cephalothorax, but are longer and more like legs. This is a specific tool that spiders use to strain the liquid, semi-digested tissues of the victim. Males have special shaped pedipalps that they use to transfer sperm to the female. At the tip of the abdomen, several pairs of limbs have changed and turned into spider warts. Each such wart is connected to a large spider gland located in the abdomen. Spider glands are of different types and each of them produces its own kind of web.

An enlarged portrait of the earthen wolf spider (Trochosa terricola) allows you to delve into the details of spider anatomy: black eyes are visible on the sides of a pair of large eyes; the brown prehensile organs just below the eyes are the chelicerae, and the short, light yellow "legs" are the pedipalps.

All spiders breathe atmospheric oxygen, so their respiratory organs are lungs or tracheas. It is noteworthy that they have 4 lungs (or the same number of tracheas), and there are species that have a pair of both. The digestive system of spiders is relatively simple. Almost all species have venom glands, the secret of which is fatal to their victims, and sometimes to large animals. In prey paralyzed by the toxin, the spider injects saliva containing highly active enzymes. This juice partially digests the tissues of the victim, the hunter can only suck in semi-liquid food. The outer covers of spiders are not extensible, therefore, for uniform growth, they often have to molt. During molting and immediately after it, the spider is defenseless, during this period it does not hunt, but sits in a secluded place.

The dolophones spider (Dolophones sp.) owes its disguise to a protective coloration and pose at the same time.

The most amazing thing in the anatomy of these animals is the sense organs. Compared to other invertebrates in spiders, they are well developed and diverse. The first thing you notice is the eyes. Spiders usually have eight of them, of which the two main ones face forward, and the rest are located on the top and sides of the head, which gives their owner a three-dimensional view of 180 °. True, there are species with six, four and even two eyes, but this is not so important, because all spiders see only light spots (but they distinguish colors!). The exception is stray jumping spiders, which do not weave trapping webs, but attack the victim with “bare hands”. They have developed sharp binocular vision for an accurate throw, which allows them to distinguish clear contours of prey and correctly estimate the distance to it. Cave species of spiders are completely blind.

To overcome the fear of spiders forever, just look into the expressive iridescent eyes of this female jumping spider (there are four of them on the front side). The view shown in the photo - fidippus mystaceus (Phidippus mystaceus) reaches a length of about 1 cm.

The sense of touch is much more important for hunting. It is unprecedentedly sharp in all spiders. Sensitive receptors and hairs on the paws allow them to capture insignificant fluctuations not only of the web, but also of the air itself. We can say that spiders hear with their feet. It has been observed that the sound of the violin awakens the hunting instinct in some spiders. Probably, the vibrations of the air caused by the instrument remind them of the buzzing of a fly. By the way, spiders themselves are by no means voiceless. large species can hiss, buzz, crackle, obviously to scare off enemies. Small ones sing mating songs, but so quietly that this sound is not perceptible to the human ear, but females hear it perfectly. The sound of spiders arises from the friction of different parts of the body from each other, that is, according to the same principle as that of grasshoppers. But the abilities of spider legs are not limited to this. It turns out that spiders can smell with their feet! In fairness, it must be said that olfactory receptors are also located on the abdomen. The smell is important not so much for the capture of prey, but for procreation. Following the odorous trail of the female, eight-legged knights cover long distances and unmistakably distinguish a mate ready for mating from an immature one. Another sense that spiders have mastered to perfection is the sense of balance. Spiders, without looking, accurately determine where the top is, where the bottom is, which is not surprising for animals, most life conductive in limbo. Finally, spiders do not have taste buds, but they do have a taste. They distinguish tasty prey from tasteless prey again with their feet!

Theraphosa blondi female in natural environment.

The sizes of spiders vary widely. The body length of large tarantulas reaches 11 cm, one of them, Blond's teraphosa, even got into the Guinness Book of Records with a leg span of 28 cm. Crumb spiders are just as amazing. So, the smallest species - patu digua - grows to only 0.37 mm!

The patu digua spider (Patu digua) is so small that it is difficult to distinguish even at this magnification, when the papillary pattern of a human finger is visible.

Due to the spherical or pear-shaped abdomen, the outlines of the body in most spiders are closer to the circumference. But in nephil orbs, the body is elongated; in some species, the abdomen can be in the shape of a rhombus, heart, or strongly flattened.

Female Gasteracantha cancriformis (Gasteracantha cancriformis) in her trapping net. This type of spider got its name (loosely translated from Latin as “crab-shaped prickly belly”) for the unusual shape of the body, in contrast to crab spiders, so named for the ability to move sideways.

Body contours can be distorted by long hairs and spines.

Curved or arched gasteracantha (Gasteracantha arcuata) is a relative of the previous species, but looks even more exotic.

Jumping spiders from the genus Simetha (Simaetha) are tiny (a couple of millimeters in size) inhabitants of the tropics South-East Asia. All representatives of this genus wear an outfit with a gold pattern.

The length of the legs also changes. In terrestrial species, it is usually small, and spiders that weave webs and spend a lot of time in the thick of foliage are often long-legged.

The color of these arthropods can be, without exaggeration, any, but given the predatory nature of spiders, it is almost always patronizing. Accordingly, the types of the temperate zone are usually painted inconspicuously: in gray, black, brown tones - to match the earth, sand, dry grass. Tropical spiders are often bright, with complex patterns.

Tweitesia are exceptionally beautiful, whose body is encrusted with shiny spots that look like sequins.

Silver-dotted tweitesia (Thwaitesia argentiopunctata).

In terms of territory coverage, spiders can be safely called cosmopolitans. They live on all continents, in all climatic zones and in all natural environments. Spiders are most diverse in the steppes, meadows and forests, but they can also be found in deserts, tundras, caves, among the glaciers of the Arctic islands and high mountains, in fresh water, human dwellings. By the way, spiders are one of the highest mountain animals - the Himalayan jumping spider lives on Everest at an altitude of 7000 m!

Prey of the Himalayan jumping spider (Euophrys omnisuperstes) - insects brought to Everest by wind.

The habitat has left its mark on the way of life of different species. Common to all spiders is that predation and the associated tendency to loneliness, although there are exceptions. Social filoponella and stegodiphus prefer to build a common network, which they hunt together ...

Saracen stegodiphuses (Stegodyphus sarasinorum) unanimously attack an unlucky butterfly. This species lives in India, Nepal, Myanmar and Sri Lanka.

and the jumping spider of Kipling's bagheera, contrary to his predatory name, herbivorous.

Kipling's bagheera (Bagheera kiplingi) carries a bloodless victim in chelicera - juicy appendages that grow on the leaves of some tropical acacias. Trees thus attract ants, which along the way protect them from pests, and the herbivorous spider uses these gifts free of charge.

Most spiders are sedentary, although among the jumping spiders and wolf spiders there are many vagrants who freely roam the open spaces and attack oncoming insects of a suitable size. Homebody species are equipped in different ways. The most primitive of them hide from prying eyes in the recesses of the soil: it is more convenient to hunt and defend themselves. Sidewalk spiders (crab spiders) hide among the petals of flowers, while sitting on one flower, they gradually change color to match their shelter.

What could be more idyllic than a butterfly drinking nectar? But a tragedy is unfolding before us: the beauty actually fell into the paws of a side-walker spider, indistinguishable in color from the flower on which it hunts.

But a good disguise does not solve all the problems, because it’s not enough to grab a victim, you also need to keep it, and it’s tiring to look out for prey for days on end. Therefore, spiders gradually moved from active ambush hunting to more reliable and passive methods of catching prey. At the first stage, they began to dig deep minks, lining them with cobwebs for greater convenience.

The trapping tube of the Rechenberg cebrennus (Cebrennus rechenbergi) is woven from cobwebs, inlaid on the outside with grains of sand.

More advanced species began to stretch the threads from the mink to neighboring stems - an ideal notification system turned out: the owner can rest in the mink, and the crawling insect, having hooked on the cobweb, will notify the spider of its approach and will be taken by surprise by the sudden appearance of a predator from under the ground. In some species, such signaling threads have evolved into complex arachnoid funnels and tubes.

Other species began to improve not the warning system, but the methods of retaining prey. To do this, they began to close the minks with earthen plugs and not simple ones, but on hinges! Spider sitting on inside hatch, keeps it closed, so that it is completely impossible to see his dwelling from the surface. As soon as the victim hooks on the signal web, the spider jumps out, drags the stunned insect into the hole, slams the lid and paralyzes with a bite. In this scenario, even strong prey has no chance to escape.

An open spider burrow with a raised lid and signal cobwebs stretching in all directions.

However, burrow hunting does not allow spiders to get off the ground, so the most advanced species stopped equipping dens and began to be content with only cobwebs, stretching it among grass, leaves and other above-ground objects.

Creating a web, the spider places it in the places of the most probable movement of prey, but so that gusts of wind, vibrations of branches, and movements of large animals do not break it.

The fact is that spiders spend a lot of deficient protein to create a web, so they value this material. They often eat a torn web, using it as a raw material for the production of a new one. The structure of the web ideally takes into account the characteristics of the favorite prey of one or another type of spider: in one case, it can be randomly stretched threads in all directions, in the other - a circle sector stretched in the corner of the shelter, in the third - a full circle.

Rainbow play of light on a circular web stretched in a gorge national park Karijini (Australia).

A thin cobweb seems fragile, but in terms of the thickness of the thread, this is one of the strongest fibers on Earth: a cobweb with a conditional thickness of 1 mm can withstand a weight of 40 to 261 kg!

Drops of water are much larger in diameter than cobwebs, but cannot break them. When they dry, the web, due to its elasticity, will restore its shape.

In addition, the web is very elastic (it can stretch to a third of its length) and sticky, so the beating victim with its movements only confuses itself even more. The web of nephil orbs is so strong that it can even hold a bird.

A tern entangled in the web of a nephila orbworm in the Seychelles. From the side of the spider, nothing threatens her, since the bird is too big for him. Usually in such cases, the nephiles simply cut off the cobwebs so that the beating prey does not spoil the entire network for them. However, the sticky web sticks the feathers together, which can cause the bird to lose its ability to fly and die of starvation.

Some spiders additionally strengthen the web with special threads - stabiliments.

The North American spider Uloborus glomosus (Uloborus glomosus) has reinforced its web in a spiral with zigzag stabiliments.

It is difficult to imagine the creator of the web outside the air, but among the spiders there were also such. Spiders from the genus of hunters roam among coastal vegetation in search of near-water insects, but on occasion they easily move along the surface of the water and even plunge into its thickness, holding on to plants.

When crossing a pond, the banded hunter (Dolomedes fimbriatus), like water strider bugs, rests on a film of water tension.

The water spider does not leave the reservoir at all; among the underwater vegetation, it creates a dome of cobwebs, from which it stretches trapping threads. The body of this spider is covered with hairs that hold air bubbles. The spider periodically rises to the surface in order to renew their supply, and drags large bubbles with it and fills the space under the dome with them. In this air tent he lives and breeds.

Water spider (Argyroneta aquatica) and the air bell he created. The body of the spider itself is also surrounded by an air bubble, giving it a silvery hue.

Spiders breed in the tropics all year round, in the temperate zone - once a year, in summer. Usually, male spiders are much smaller than females (in some species, 1500 times!), Less often - almost the same size as them, and only in a water spider, males are a third larger than their girlfriends. In addition to size, males, as a rule, are also distinguished by bright colors. Mating in these arthropods occurs unusually - without direct contact of the genitals. First, the male fills the pedipalps with sperm and sets off on a journey with this gift. Having followed the trail of the female by smell, he proceeds to solve the main problem: how to get close to the gluttonous and huge girlfriend without awakening her hunting instinct? Different species follow different strategies. Some spiders warn of their appearance with a characteristic twitching of the web - this “call” should make it clear to the female that there is no prey in front of her, but it does not always work, and often the boyfriend has to flee at full speed. Other males build a small mating net next to the female's web: rhythmically twitching it, they invite their girlfriend to a closer acquaintance. Male wandering spiders, which do not weave webs, perform a mating dance, raising their paws in a certain sequence, like traffic controllers. In some species, daredevils manage to involve the spider in the dance. Males of the amazing Pisaura (Pisaura mirabilis) rely on a tried and tested trick: they go on a date with a treat - a fly wrapped in a web. The most timid of spiders mate only with a recently molted female: with soft covers, she herself is defenseless and not prone to attack. During mating, the male introduces the pedipalps into the female's spermatic tract, sometimes entangling her with cobwebs as a safety net.

Acrobatic sketch performed by a male peacock spider. In addition to raising their legs, males of all species of this genus also show an unusually colorful abdomen, raising it like a peacock's tail. It is almost impossible to see this miracle in nature, since the size of peacock spiders is only a couple of millimeters.

Usually an intimate meeting takes place in private, but sometimes several males look after one female and then they arrange fights among themselves. It happens that the female mates successively with several males. After mating, the spider often eats one or all partners. In some species, males survive by agile flight or cunning.

The male flower spider (Misumena vatia) climbed onto the back of the female and became inaccessible to her. For him it the only way protect yourself after mating, as the forces of the partners are too unequal. Some types of cross-spiders use the same method.

In more rare cases, the male and female part peacefully or even live in the same nest, sharing prey. A few days or weeks after mating, the female lays her eggs in a webbed cocoon.

The cocoon of the brown agreca (Agroeca brunnea) is two-chambered: in the upper chamber there are eggs, and in the lower chamber there are nurseries for newborn spiders.

The fertility of different species varies from 5 to 1000 eggs, if there are many eggs, then there can be up to a dozen cocoons. The size of the cradle is small - from a couple of millimeters to 5 centimeters in diameter; coloring can be white, pink, green, golden, striped.

Gasteracantha cancriformis cocoons are as unusual as these spiders themselves. The females attach their golden-black-striped cradles to the underside of the leaves.

If in relations with male spiders they demonstrate dark side of his nature, then in dealing with offspring - light. Females carefully attach cocoons in a secluded corner of the hunting net, their own nest, burrow, and vagrant species carry them with them, holding them with chelicerae or gluing them to the abdomen. Females of the Venezuelan cross (Araneus bandelieri) weave a common cocoon, and some species, like cuckoos, throw their offspring into the nests of their neighbors. If the cocoon is left in a secluded place, then after hatching, the spiders are left to their own devices. Until the expiration of the first three molts, they keep crowded, and then disperse. Females carrying cocoons with them often take care of their offspring and after birth they are spiderlings. They carry babies on their bodies and provide food.

Female of one of Pisaura species (Pisaura sp.) with a precious burden glued to her abdomen.

Young spiders living in open landscapes often resort to settling with the help of a web. To do this, they climb a stalk or twig higher and release a cobweb, but do not attach it as when weaving a net, but leave it to hang free. When the thread is long enough, the wind picks it up along with the spider and takes it far, sometimes over a hundred kilometers. The years of such a web are especially noticeable in August-September.

Web with a brood of spiders. While the kids are small, they keep crowded.

In species of the temperate zone, wintering often takes place in the egg stage, but if young spiders hibernate, they often show resistance to cold and may appear on the snow during winter thaws. Most small spiders live no more than a year, the largest tarantulas in nature live up to 7-8 years, and all 20 can live in captivity.

This is not snow, but a carpet of cobwebs that covers the shore of one of Australia's reservoirs.

The prey of spiders is varied. First of all, their victims are mobile, but not too strong insects- flies, mosquitoes, butterflies - they are the most likely to get into the net.

If the victim is especially slow and defenseless, then the spider does not hesitate to attack prey many times larger than itself: a caterpillar, an earthworm, a snail.

Nomadic species and spiders that live in minks are more likely to come across flightless beetles and orthoptera.

Hutchinson's Mastophora (Mastophora hutchinsoni) uses a very unusual way of hunting. She weaves a gossamer with a sticky drop at the end, hangs with this boladoras in an outstretched paw and swings it until some insect sticks to the drop.

The largest tarantulas prey mainly on small vertebrates - lizards, snakes, frogs. Occasionally, small birds (more often chicks) become their prey, which is reflected in their name and at the same time gave rise to a prejudice that tarantulas eat only birds.

Deinopis spiders (Deinopis sp.) first weave a square net, and then, holding it straight, creep up and throw it on prey.

Amphibiotic and water spiders catch tadpoles, aquatic insect larvae, fish fry and even adult small fish. Some species of spiders have a narrow food specialization, for example, they hunt only ants or spiders of other species.

Large vertebrates are never attacked by spiders, but some venomous spiders may bite in self-defense. Spider venom is local and general action. The local venom causes severe pain at the site of the bite, redness (blue), swelling and tissue death, in some cases so deep that they are exposed internal organs. A general venom causes headache, nausea, vomiting, convulsions, mental agitation, skin rash, palpitations, kidney dysfunction, in severe cases, suffocation and death. Fortunately, most poisonous spiders belong to tropical exotics, and of those common in densely populated areas, the South Russian tarantula and karakurts are the most dangerous.

The South Russian tarantula (Lycosa singoriensis), although infamous, is not as dangerous as the karakurt.

These spiders live in the herbage of steppes and semi-deserts. Southern Europe, Asia and North America, and livestock also suffer from their bites, which in the past sometimes led to a mass death of grazing camels, sheep, and horses. The venom of the karakurt is 15 times stronger than the venom of the gyurza, but unlike the snake, the bite of the spider is shallow, therefore, as a first aid, cauterization of the bite site with a burning match is effective. True, this measure is saving only in the case of immediate (within 1-2 minutes) application. If first aid was not provided, then the life of the victim can only be saved in the hospital with the help of anti-karakurt serum.

The female karakurt (Latrodectus tredecimguttatus) guards cocoons with eggs, during this period she is especially aggressive. The species shown in the photo lives in arid regions of Europe and Asia.

Although spiders seem to be dangerous and invulnerable predators, they are defenseless against many enemies. They are hunted by all kinds of birds, small animals, lizards, frogs. Bustards, noses and dormouse dormice do not even give in to poisonous species: birds stuff their stomachs with karakurt, and animals hunt for tarantulas. Among the invertebrates there are also brave men who are ready to eat their eight-legged brother. Spiders are attacked by praying mantises, bears, predatory beetles and even ... flies, however, not ordinary, but predatory.

These female scorpion spiders (Arachnura melanura) display a variety of intraspecific coloration. Females of this species have an elongated abdomen, which they can move like scorpions. Despite their formidable appearance, they do not have a sting, and the bite of these spiders is painful, but not dangerous. Males are smaller and of a regular shape.

Dead tarantula infected with cordyceps. Outgrowths that look like deer antlers are fruit bodies mushroom.

This Thai argiope (Argiope sp.) sits in a trapping net with legs folded in pairs and stretched along the stabiliments. So it becomes part of the web pattern and ceases to interest others.

In this regard, spiders have developed a variety of means of protection (some of them also serve as adaptations for hunting). This should include patronizing coloration and body shape, as well as special postures.

Some spiders freeze in the center of the web with outstretched legs, becoming like a stick, phrynarachns and pasilobuses imitate bird excrement in this position and even emit an appropriate smell that attracts flies!

Seeing danger, nomadic species take to their heels; spiders weaving a web, on the contrary, land on the ground; some species take a threatening posture with their paws raised high; small spiders shake the web so that their contours in the trembling network seem to be blurred.

The sickle-shaped pasilobus (Pasilobus lunatus) is indistinguishable from the excrement of small animals, but it only looks like this in sunlight.

As if in reward for the unassuming appearance nature endowed this spider with the ability to glow in ultraviolet light.

Venomous spiders bite while tarantulas… shaken, while the hairs covering their body break off and rise into the air. When inhaled and on the skin, they cause irritation.

Rechenberg's already familiar cerebrennus never ceases to amaze: in case of danger, he flees, tumbling over his head!

It can only be surpassed by the golden-yellow carparachna living in the Namib Desert.(Carparachne aureoflava), which does not run away from enemies, but rolls head over heels from the dune, developing a speed of up to 1 m / s. This speed is not so small, because in order to reach it, the carparachne must make 40 somersaults over its head!

Paraplektana spider (Paraplectana sp.) dressed as a ladybug.

Some burrow spiders create three-chamber underground shelters to protect against wasps: if the enemy managed to crack the first door, the spider moves to the next compartment of the hole, which is also locked with a lid, and so on. At the same time, burrows can be configured in such a way that the enemy is simply not able to find the spider in the underground labyrinth.

The female of the severed cyclocosmia (Cyclocosmia truncata). This burrow spider, originally from Mexico, uses the most original way of protection - it plugs the entrance to the hole own body. The blunt end of the abdomen perfectly matches the size of the hole, so that a perfect cork is obtained, which is very difficult to pull out from the outside.

The front side of the abdomen of the cyclocosmia resembles an ancient seal.

Spiders have long evoked mixed feelings in people. On the one hand, they were feared because of their unpleasant appearance and poisonousness. The infamous karakurt in North America was nicknamed the "black widow", and the word "karakurt" in Kazakh means "black death". The subconscious fear of spiders is so strong that some people, even now, with little or no contact with dangerous species, are terribly afraid of these arthropods - such mental disorder called arachnophobia. On the other hand, people have always been fascinated by the ability of spiders to weave webs, and attempts have been made to extract practical benefits from this. Also in Ancient China they knew how to make a special “fabric of the eastern sea” from the web, the Polynesians used a thick web for sewing and making fishing nets. In Europe in XVIII-XIX centuries isolated attempts were made to make fabric and clothing from the web; in modern industry, the web is used in instrument making. However industrial production It was not possible to give rise to this material due to the difficulties of keeping and breeding a huge number of producers. Now spiders are bred in captivity as exotic pets, and large tarantulas, which are convenient to observe, are most popular among amateurs. But other species of these arthropods also deserve protection as useful and very effective regulators of the number of harmful insects.

Smith's Brachypelma (Brachypelma smithi; female) is one of the most popular tarantula spiders. Due to the massive catch for sale in their homeland, in Mexico, it has become rare.

Read about the animals mentioned in this article: horseshoe crabs, ants, grasshoppers, praying mantises, ladybugs, crabs, snails, frogs, snakes, lizards, peacocks, cuckoos, deer.

For some people, spiders are a phobia, while others, on the contrary, are very sensitive to these creatures. And many people also believe that spiders are insects. Next, we will try to figure out whether this is so.

Description of the spider

The spider is one of the ancient creatures of our planet. He is much older than man. The remains of his life, namely the web, were found in amber, which is more than 100 million years old. There is also evidence that arachnids lived on Earth as early as the Paleozoic era, which is about 2.5 billion years ago. During this time, these creatures have changed little in appearance, they are predators and feed mainly on insects.

You can meet a spider in all corners of the planet. Spider individuals were found on Everest, at an altitude of almost 7000 m above sea level, and one species even lives in water. This creature loves warmth, which is why most of the known 40,000 species live in tropical climates.

In order to understand who it is, what kind of animal, to which class it belongs, one should understand scientific classification this creature. In descending order, it looks like this:

• realm: Animals;
• type: Arthropod;
• class: Arachnids;
• squad: Spiders.

Important! Spiders only bite when defensive, so they don't need to be disturbed to avoid trouble.

Is a spider an insect or not?

Looking at the appearance of the spider, many will probably say that this is not an animal at all, but someone else. Most of all, it looks like an insect, but is it?

We find the quickest answer in the same classification: both insects and arachnids belong to the animal kingdom and the type of arthropods. But then they are further divided into classes - insects by themselves, and arachnids by themselves, since these classes have significant differences.

That is why the spider is a separate class of arthropod creatures.

General signs

Spiders and insects have a number of common features, as they belong to the same type of arthropod:

• have a chitinous skeleton to which muscles are attached;
• the eye of an arthropod is usually formed by many eyes and is called facet;
• all females of this class reproduce by laying eggs.

Did you know? The strongest web is that of the nephila spider. It can withstand up to 80 g of weight.

Main differences

Spiders and insects were assigned to different classes due to the fact that there are significant differences between them:

• a spider has 8 legs, and an insect has 2 less;
• an insect has 3 body segments, and a spider has 1 less;
• the spider creates a web, but the insect does not;
• there are many more species of insects than arachnids;
• the spider is distinguished by the fact that it produces poison, which is needed for external digestion;
• in arachnids, unlike insects, there is no metamorphism (transformation) in the life cycle;
• the communication system and nervous system of an insect are many times more complicated than that of an arachnid.

Hunting and what to eat

The spider is a true predator by nature. The basis of his diet is insects, sometimes he catches even small animals. Only one species feeds on plant foods, this exception is the jumping spider.

The spider hunts with the help of a network skillfully woven from the web. There are arachnids that use spider shots in hunting, hypnotize the victim.

After catching the prey, the spider injects poison and digestive juice into the prey, and after a while sucks the nutrient solution out of the prey.

Structural features and description of species

The body of this creature consists of 2 segments, called the cephalothorax and abdomen, which are connected by a stalk. Simple eyes are located on the head, they can be from 2 to 8. In certain species, these eyes are very developed.

Three pairs of warts located on the belly secrete a liquid that is very much like glue. Freezing in air, this liquid turns into a web.
The spider has 8 legs, and in front there are processes-claws with poison.

Of the more than 40,000 species of spiders, we will look at a couple of the most famous and interesting.

Did you know?At one time, females of some spider species can lay up to 20,000 eggs.

They inhabit steppes and forest-steppes all over the planet. They are different from their brethren huge size. The body of a tarantula can grow up to 10 cm, and the leg span can reach 30 cm. The female is larger than the male and her weight is almost 100 g.

The structure of the tarantula does not differ from other spiders, but has brown or red hairs on the body and legs. He has 8 eyes. Such a “baby” lives in earthen minks up to 30 cm deep and hunts at night.
Its main diet is insects and small amphibians. In case of danger, the tarantula bites. Its bite resembles that of a wasp and is not fatal. You can only observe redness at the site of the bite, weakness. Very rarely, breathing becomes difficult and vomiting and nausea appear.

Important!If you have been bitten by a spider, you should definitely consult a doctor. In addition to the main danger, spider venom can cause severe allergies.

Karakurt spiders differ from their relatives in their special poisonousness. Their venom can be fatal to humans, it is more than 10 times stronger than cobra venom. These creatures live in southern regions Russia, in Kazakhstan, in the south of Ukraine, in Central Asia and America. They do not live in open areas, but hide in mouse holes or rocks.

The male spider does not exceed 1 cm in length, and the female can be 3 times larger. The latter has red spots on the abdomen.

Karakurts feed on small insects, placing the net horizontally above the ground.
It is noteworthy that only the female karakurt is poisonous, especially in mating season. She can bite through not only the skin, but also the nails. When bitten by a karakurt, assistance should be provided within the first 20 minutes.

Many people identify spiders as insects, but they really aren't. These are animals that belong to a separate class of arachnids. You should take a closer look at these creatures, as some of them are dangerous to humans. But if you know "by sight" dangerous species you can certainly avoid trouble.