Small cross spiders have a cross on their back. What to do if bitten by a spider

The cross spider is a representative of the genus of amorphous spiders of the orb-weaver family. More than 2 thousand species of crosses are known.

Characteristic feature appearance this spider has spots of light brown or white, located on the upper side of the belly, which form a cross.

Appearance

The abdomen itself is rounded with no segments. If you look at its lower part, you can see 3 pairs of arachnoid warts, which contain about a thousand glands. It is the glands that are responsible for the production of webs for a variety of purposes: to build a trap, weave a cocoon, or to create a shelter.

Female size exceeds the size of the male. For example, the body length of a female is 17–40 mm, and that of a male.

10–11 mm. This type of cross has a body cavity mixed type or in other words mixocel. This cavity was formed as a result of the merger of the primary and secondary cavities. The body of the crusader is covered with a yellow-brown chitinous shell. During molting, the cross sheds the shell, thereby renewing the chitinous layer.

The cross has 10 limbs:

The cross spider has a very poor vision, despite the fact that he has 4 pairs of eyes. This spider distinguishes only light, shadow and blurred silhouettes. But this does not prevent him from having excellent orientation in space, because he has a well-developed sense of touch. It is carried out thanks to tactile hairs covering the body. Every type of hair has its own function: some perceive sound, others detect changes in air movement, and still others react to various kinds of stimuli.

The lifespan of a spider is from 1 to 2 years and depends on the type of crusader.

Respiratory organs and heart

The crusader breathes using his abdomen, because the organs responsible for this important function, are located exactly there. Respiratory organs are presented in the form of a pair of pulmonary sacs with numerous leaf folds. They contain air and hemolymph circulates, while being enriched with oxygen. This name refers to the fluid that flows in the vessels instead of blood. The respiratory organs of the cross also include trachea-tubes, collected in two bundles. They open through a hole located at the bottom of the abdomen.

The heart, in the form of a long tube, is located in the dorsal part of the abdomen. Large vessels will withdraw from the heart.

Excretory system and digestion

The excretory system is presented as:

• Coxal glands. A system of canals departs from them, which ends in the form of excretory ducts in the area of ​​​​the base of the walking legs.
• Malpighian tubes. With their help, metabolic products leave the crusader's body.

Digestion in the cross spider is external. In other words, the crusader’s body is not able to digest food, so it builds traps from cobwebs.

Features of the web

The crossers are updating their web almost every day, due to the unsuitability of the old one. The reasons why a spider needs to change its web are:

• Gaps due to prey being trapped.
• Holes caused by large insects that are unsuitable for spider feeding.

The web is being weaved at night. This is explained by the fact that at night the crossbird feels completely safe, because birds that feed on insects have been sleeping for a long time. The new prey trap will be ready for use in the morning.

The spider has a scheme for weaving a web, laid down at the genetic level. The web always has a certain number circles and spirals, and the spaces between the weaves are the same. Young males build webs no worse than adults until they reach sexual maturity.

Reproduction

Spiders begin to mate in the autumn season. A male who has reached sexual maturity, goes in search of a female who is waiting for him in her weaving. As soon as the spider has found its chosen one, it attaches a thread to its web, as if inviting it to itself. For the female, this means that it is time to reproduce and she leaves her network. The male representative dies after mating.

In turn, the fertilized female builds a cocoon where she will subsequently lay her eggs. For several days the cocoon is under the protection of the mother. The female then finds a secluded place in the cracks of the walls, in which the cocoon survives the winter. The female dies, and spiders emerge from the cocoon in the spring. In summer, the new offspring are ready to reproduce.

Description of popular types

Habitat

This type of spider prefers temperate and tropical climates. climatic zones. Different kinds The cross can be found in countries such as:

The cross spider feels comfortable in damp areas, near water, as well as in parks, gardens and forests. In other words, the crusader can be found wherever there are trees . After all, it is between the branches crusader trees and weaves his web. The spider's orb web is found under roofs and in doorways of abandoned houses.

Nutrition

The spider's diet includes:

• flies;
• small grasshoppers;
• vile;
• mosquitoes;

Males do not eat well, so they grow at a slow pace. Females have an excellent appetite. In 24 hours she is able to eat an amount of food equal to her weight.

If food unsuitable for the spider in the form of poisonous or large insect, then the crusader seems to cut out the object by breaking the threads. Spiders are afraid of wasps that lay eggs on living creatures and avoid them. After all, the body of a spider is favorable environment for the development of their larvae.

When a spider hunts, it sits close to catcher net in the foliage or in the very center of the web and waits for the victim to become entangled in the sticky threads. When prey falls into the web, the spider's hairs pick up the vibrations of the web. The spider then injects into its victim gastric juice and rolls it into a cocoon created from a spider's web, and waits for dinner to be prepared. Stomach juice turns the prey into a solution, which the spider soon drinks.

For whom is the cross spider dangerous?

Crusader venom contains substances such as hemotoxin and neurotoxin, which are fatal only to invertebrates, as well as small vertebrate organisms. For humans, cattle, sheep and other living organisms, the bite does not pose any particular danger, and some do not even notice it. The site of the bite can be recognized by slight pain, which passes very quickly. Spiders never attack first on a person, and bite only in case of protection, if the web was accidentally touched.

• How do crusading spiders move along their own web, since its threads are covered with an adhesive substance? The fact is that this arthropod moves along radial threads on which there is no adhesive substance, so it does not stick.
• The web of the cross can show the composition of the air, which is why it is so actively used in microbiology.
• Spiders aren't the only ones who need webs. Thanks to the strong threads of the cross spider's web, some tropical residents use it to weave jewelry, fishing gear, and also to make fabrics.

The common cross can be found throughout Europe. Its favorite habitats are forests, bushes, and gardens. Typically, crosses can be seen at a height of about 30-150 cm above the ground. The cross spider loves damp places where there are a lot of mosquitoes and flies - the favorite food of this spider. However, such habitats often pose a certain risk for the spider.

That is why many crosses are generally in the crowns of trees at a height unattainable for enemies. They build themselves a secluded shelter from leaves, stretching their web between. By the way, wheel-shaped webs can often be seen under the eaves of abandoned architectural buildings, as well as in the window frames of your own home. Since the web is an integral attribute of the life of the cross spider, its existence without it is simply impossible.

A strong web is the main attribute of the cross’s habitat

In principle, enemies do not sleep even at the height of tree crowns. In this case, the crossman’s well-woven web comes to the aid of the crossman (although not always), which he is forced to maintain intact and safe every day. Due to restless flies and wasps, the fishing net of the cross is constantly in need of minor repairs. In addition, it is destroyed by small and large insects, animals and even humans (for example, lumberjacks and woodcutters).

Since the basic law of survival of the cross spider is a tight and timely woven web, the method of constructing the web of the cross spider is quite curious. The substance coming out of the arachnoid warts located on the edge of the abdomen of the cross frozes in the air and forms threads of amazing and extraordinary strength.

The cross spider attaches the main thread from the highest point to the place that it has chosen as its home. Basically, it occurs between two branches or trees. When the cross secures the first part of the “foundation”, it begins to swing until it grabs onto the adjacent side branch. The result is a crossbar.

To pull the upper transverse thread tightly, the crosser needs to move from one tree (or branch) to another, and this is quite expensive. If such a thread is pulled tight enough, the spider begins to strengthen it with additional short transverse threads.

As soon as the main outer threads are stretched, a kind of cobweb frame will appear. After this, the cross moves along it, stretching its transverse threads. It is curious that this miracle builder calculates his every step with geometric precision. The cross takes the intersection of its diagonals as the center of the future web and begins to pull the radial rays. When this stage is completed, the cross spider will only have to connect the resulting threads in a circle.

The cross spider, also known as the crusader, araneus, belongs to the family Araneidae. There are 621 species in the genus of crosses. Spiders live all over the world and are common in our area. You can meet a predator everywhere - in the forest, field, edge, park, vegetable garden, yard, outbuildings. Often crawls into the house through cracks in the walls, open windows, doors.

Description and photo of the cross spider

The body size of females is from 20 to 40 mm, that of males is 10 mm. Consists of a round convex abdomen, cephalothorax. Body covered strong shell, legs - with villi. The crusader spider has 10 limbs, of which 4 pairs are walking legs. The front ones perform the functions of claws - they capture the prey and hold it while feeding. The paws are symmetrical to the size of the body. The structure does not differ from the typical one. The cephalothorax is connected to the abdomen by a thin bridge.

How many eyes does a cross spider have - 8. Placed on the front of the head. 6 in the center, 2 large on the sides. This provides a broad outlook, but does not provide good vision.

Interesting!

The spider is myopic, sees everything in general outline– movement, shadow, silhouette. The organs of smell and touch help the cross to navigate in space. Located on the legs. Finding itself in an unfamiliar place, the spider carefully feels the space initially with its paws, and then moves.

What a crusader looks like depends on the species. The body structure is the same, but the color is different.

• The meadow crossweed lives in places with moist air, warm climate, dim light. Painted in brown, yellow, red tones. On the belly on the upper side there are white spots in the shape of a cross. Thanks to this identification mark, all species of araneus are called crosses. Meadow predator on the grass, hunts small insects.
• The forest cross differs from the garden and meadow in its darker color. The body is dark brown with white stripes. The characteristic white or brown sign of the cross is clearly visible on the abdomen. The paws are long. The largest cross in Russia. The size together with the leg span reaches 4 cm.
• The Far Eastern cross is different large sizes. Habitats: forest, field, meadow. The color is brown with different shades. The cross on the abdomen is white or yellowish. It weaves the largest web, which reaches 2 m in diameter. Even frogs, toads, and snakes can become entangled in strong webs.
• An orange or yellow spider with a cross on its back is an ordinary crusader that lives in shady places in forests, fields, meadows, and gardens. Araneus angulatus is a rare species listed in the Red Book. Body size is about 18 mm.
• The predator with a red cross on its back is a type of meadow cross. Bright spots scare away enemies, but do not mean that this representative of the genus is more poisonous.
• A black spider with a white cross on its back is a crusader that lives near swamps, in the forest, in fields, and rarely approaches a person’s house. Outwardly it resembles a tegenaria.

What a cross spider looks like depends on the species, but what distinguishes them from other representatives of arachnids is a characteristic pattern on the back in the shape of a cross. This is where the name comes from.

Where does it live?

The species is distributed throughout Europe, some varieties live in North America. Favorable conditions existence is high humidity, heat, lack of direct sun rays. Ideal habitats are coniferous forest, swamps, edges, hedges. Less often they settle in meadows, fields, gardens, vegetable gardens, outbuildings, and residential buildings. There are about 30 species of crosses living in Russia and the CIS countries.

On a note!

Once in a person’s house, the spider chooses places away from noise and light. Occupies corners at the top of the room, below behind the furniture. Weaves a web. It feeds on “domestic” insects – , . To get rid of a spider with a cross on its back, you need to remove its web, throw it outside, and poison the “living creatures.”

Lifestyle

Common cross spider – resident wildlife, but under certain circumstances. Leads night image life, during the day it sits motionless in a shelter or on a web of webs. He weaves it at night. It makes a shelter out of leaves and builds trapping nets between the branches.

Experts managed to find out how the female cross weaves a web. The network consists of 39 different radii, which expand as they move away from the center, 35 spiral turns, 1245 points of contact of threads. The radius of the web of the large Far Eastern cross reaches up to 2 m.

Interesting!

At night the female weaves a net, and during the day it catches prey. The spider eliminates the damaged areas and forms new coils in their place. Natural enemies are birds, but with the onset of darkness their activity decreases. The cross can work quietly.

The lifespan of a spider is theoretically 2 years. IN natural conditions it is somewhat shorter. How long does a cross spider live? pet, depends on proper care. Quietly lives up to 2 years.

Nutrition

The main diet consists of insects of different sizes. The spider's trapping nets catch flies, wasps, hornets, grasshoppers, locusts, caterpillars, and butterflies. Snakes, frogs, toads, and mice get entangled in large, strong webs.

Internal digestive system absent, liquefaction of food occurs externally. The spider bites the victim, injects poison that paralyzes the muscles and immobilizes the prey. The cross releases saliva into the insect’s body, envelops it in a web, and waits for several minutes. In 5-20 minutes, the insides of the prey turn into a liquid mass, which the predator sucks up.

Reproduction

The mating season begins at the end of summer. The female waits for the male on her web and senses his approach by the vibrations of the web. After fertilization, it spins a cocoon and lays up to 250 eggs inside. He carries it with him and then leaves it in a secluded place. The young animals spend the winter in this state. Spiders are born at the end of April.

The maturation period lasts several months. During this time, the nymphs molt about 5 times, increase in size, and acquire a characteristic color. By the end of summer they become sexually mature. Caterpillars serve as food for the young animals.

On a note!

How adult spiders overwinter - they hide in cracks in walls, utility rooms, forest litter, tree hollows. They become active as air temperatures rise in spring.

Poisonous or not crusader

The poison is toxic to invertebrates and vertebrates. It has an effect on the body of rats, mice, humans, and rabbits. Sheep, horses, guinea pigs, and dogs are resistant to poison. For insects and invertebrates, a crusader attack is fatal. Animals experience temporary deterioration in well-being and external irritation.

The Crusader is not dangerous to humans. When it sees people, the spider tries to hide unnoticed. However, in the event of a threat to own life may bite. There are 2 small spots left on the body. Initially there is pain and burning. The next day, suppuration occurs. In people with weakened immune systems, children get worse after general health. There is weakness, nausea, headache, dizziness, abdominal discomfort. The condition returns to normal in a few days.

The cross spider, or Araneus, belongs to the orb-weaver family, a genus of araneomorphic spiders. In total, there are more than 1000 species of representatives of this genus in the world, but in Russia and the CIS countries you can find from 15 to 30 species. Crosses live mainly in damp and damp places - in fields, meadows, forests, along the banks of reservoirs and rivers.

The structure of the cross spider

The size of the male is 10-11 mm, the larger female is 17-26 mm. The cross has 8 legs and a large rounded abdomen. On the upper side of the spider's abdomen, white or light brown spots form a semblance of a cross, hence the name of the spider. The cross spider has 4 pairs of eyes, like most spiders; they look in different directions, providing their owner with a fairly broad horizon. However, spiders see poorly, they are myopic and distinguish mainly shadows, movement, and the contours of everything that surrounds them.

Features of the cross spider

Spiders are dioecious animals. After mating, the male dies, and the female begins to weave a cocoon from the web for eggs, which she usually lays in the fall. The cocoon turns out to be quite dense; the female carries it on herself for some time, and then hides it in any safe place - in a crack in the bark of trees or behind a loose piece of bark. In spring, young (juvenile) spiders emerge from the cocoon. They become sexually mature by the end of summer, after which the female that gave birth to them dies.

In the first days of his life, the male cross spider also builds a web - he needs to eat something. But upon reaching maturity, he begins to wander in search of adventure and, of course, noticeably loses weight. During this period, he is driven by only one desire - to find the female’s web.

When the female's web is found, he makes every effort not to get to her for lunch. To do this, he weaves a thread for himself down from the edge of the web - for retreat. Then he carefully tugs the thread. The female immediately rushes in search of prey, and the male retreats down the rescue thread.

This is repeated several times until the female understands that it is not the prey who is pulling the web, but her long-awaited partner. Then she changes her anger to mercy, and the spiders mate. But the male cannot let down his vigilance, because... after mating, the hunting instinct awakens in the female again. If he does not escape in time, he may well be eaten.

Reproduction of the cross spider

The cocoon, which the female weaves in autumn, contains from 300 to 800 amber-colored eggs. Under the protection of the cocoon, future spiderlings are not afraid of either cold or flood - it is very light and does not get wet. The eggs wait out the winter in the cocoon, and in the spring small spiders emerge from the eggs. For some time they sit inside the cocoon, afraid to leave such a cozy shelter. But gradually they spread out and begin to live on their own.

It is clear that it will be very difficult for such a huge offspring to get settled in life. Competition is very high, some will die of hunger, and others will be eaten by their relatives. Therefore, the young spiders face a serious task - to disperse as quickly as possible in order to increase their chances of survival.

Their legs are small and weak, so the spiders move, gliding with the help of their web, like real aeronauts. With a fair wind, a spider can fly a distance of 300-400 km. When the wind subsides, the web falls to the ground, the spider throws it away and begins to settle in a new place. If he is lucky with the site, he will be able to catch up to 500 insects per day with his nets. The hunt is on constantly.

According to naturalists, millions of spiders live in meadows, fields and forests, destroying entire legions of insects, including those dangerous to humans and their households. If it were not for spiders, the number of flies, mosquitoes, gnats, midges, moths and aphids would be several orders of magnitude greater and could seriously poison our lives. Experts do not even rule out the possibility of using spiders in biological control with pests.

Web of the cross spider

Cross spiders catch their prey using webs. More precisely, their females - male spiders do not weave webs. Female spiders guard their prey either in the center of the web or sitting next to it, on a signal thread. Mostly flies or mosquitoes get caught in the web. If it comes across prey that is too large and inedible, for example a wasp, the spider can free it by tearing off the web.

The spider either eats the caught prey immediately on the spot, or, if it is not too hungry, drags it into a secluded corner or entangles it in a web. Around the web, under the leaves, you can find a whole food warehouse of flies entangled in the web, stored for a rainy day.

The behavior of the cross spider

How does a spider hunt? When a fly or any other insect gets caught in a web, the spider senses the vibration of the trapping web, it crawls into the victim and kills it with a bite of its poisonous mandibles, or chelicerae. The fly stops shaking the web, and the spider calmly swaddles it with a bundle of thin threads, pulling them out of the abdomen with a pair of its legs.

Having snacked on the surrounding threads, the spider takes its breakfast and goes to the center of the web to have a meal. He crushes his prey, injecting digestive juices into it. When the fly has digested inside its shell, the spider sucks up the semi-liquid contents into which the fly has turned and throws away the victim’s skin. During a successful hunt, a spider can eat about a dozen flies in one sitting. The venom of cross spiders is dangerous only for small insects; it cannot harm humans.

Habitat of the cross spider

Crossworts live mainly in the crowns of trees, make a secluded shelter from the leaves, and stretch the web between the branches. The wheel-shaped web can be found in a forest, grove or neglected garden. Sometimes it can be found in bushes or in window frames and under the eaves of abandoned houses.

The fishing net is constantly in need of repair; it is destroyed by both small and large insects, so every couple of days the cross spiders dissolve their web and make a new one. They usually do this at night, and by morning the new web is ready for new prey. Thus, at night the spider is relatively safer, because it natural enemies, insectivorous birds, sleep at night. It doesn’t need light to build a web, it’s good enough developed sense touch.

The enemies of the cross spider are also flies and wasps, which lay eggs in the bodies of their victims. For example, the fly Melanophora rugalis - taking advantage of the spider’s immobility, it can fly up to it, sit on its back and in the blink of an eye lay an egg in its body.

Web of the cross

The web of the female cross has exactly 39 radii, 1245 points of attachment of the radii to the spiral and 35 turns of the spiral - no more, no less. The webs of all spiders are as similar to one another as two peas in a pod, because all the necessary data is genetically enshrined in their heredity. Therefore, even small spiders know how to build webs and catch prey.

Any web is not only beautiful in its symmetry and delicacy, it is very rationally arranged. All the threads that form it are very light and, nevertheless, very strong, and are connected in such a way that they only work to break.

How does a spider manage to build such an even, symmetrical web that is several dozen times larger than itself? A spider (more precisely, a cobweb), having climbed onto a branch or tree trunk, releases a long web thread from its abdomen. It is picked up by a stream of air, and the spider waits patiently until the thread catches on something suitable.

If this does not happen and the thread hangs, the spider pulls it towards itself and eats it. Then he runs to another place and tries again. And so on until the thread is caught. Then the spider crawls to the hooked end of the thread and secures it well. Then it descends on its thread to some support. There he also firmly fastens this thread - now 2 threads are already fastened.

The spider returns along the second thread and drags along the third, which it secures at the starting point, i.e. where the first thread came from. The triangular frame - the basis of the future web - is ready. Inside this frame, the spider stretches several threads that intersect in the center. The spider marks the center of the web with a lump and begins to extend all its numerous radii from it, fastening them with a spiral thread, and then lays trapping threads. At the intersection points of the spiral and the radius, the spider binds them with its legs.

Note that the angles between all radii and the distance between the turns of the web are strictly constant values. How can such a little creature manage to maintain your web in strict accordance with geometry? For this you need at least the simplest measuring device. And, imagine, the spider has it! This is his first pair of legs that can act as a scale ruler.

While working on the web, the crossmaker regularly checks the distance between the spirals. His natural tool is so precise and reliable that it allows you to work in pitch darkness. The last step in creating a web will be a signal network, the end of which is laid to the spider’s shelter. It takes a spider several hours to build the entire web. painstaking work and about 20 meters of web.

From a chemical point of view, the web is a complex protein polymer - fibroin. The many glands of the spider's abdomen form this viscous liquid, which quickly solidifies in air in the form of thin filaments. The spider can produce several different types of web with different properties. For the frame of the web he makes a dry and thick thread, for the cocoon - silky and soft, for the catching spiral - thin and sticky. Why doesn't the spider itself stick to its web? Everything is very simple - he runs only on non-adhesive threads, and diligently avoids touching adhesive spirals.

The polymer liquid comes out from the glands on the spider's abdomen through thin tubes and hardens into very thin threads. If the spider needs special strength, it can weave several of these threads together. Scientists in last years They are seriously studying the properties of spider “silk”. It turned out that it has many unique properties.

The technology for producing spider web threads is similar to the production of synthetic fibers. But in terms of strength, no synthetic fiber can compare with spider fiber - it can withstand loads of up to 260 kg per 1 sq. mm, which is stronger than steel. This is why residents of the tropics make nets from spider webs to catch birds, bats, insects, and even weave fishing gear.

The web is so elastic that it can stretch up to 30% of its length and shrink back to its original length. Its lightness and subtlety are involuntarily amazing, because 340 grams of web is enough to encircle Earth along the equator!

The use of cobwebs in agriculture and medicine

People have long tried to make fabric based on spider webs. In Germany, back in the 16th century, ribbons and various decorations were woven from cobwebs in villages. Then in France, artisans came up with the idea of ​​​​making gloves and stockings from spider webs, which caused complete delight among fashionistas.

But it turned out to be impossible to launch this technology into large-scale production, and this was convincingly proven by the physicist and zoologist Reaumur. For such production to become profitable, it is necessary to contain and feed hundreds of thousands of spiders. But to feed them, it would be necessary to catch several million flies every day, which was completely impossible to implement in practice.

However, people still use the web, even today. For sights (crosshairs) in various optical instruments (microscopes, telescopes, sights, etc.), spider webs are simply ideal. Microbiologists have also found use for it, developing a unique air analyzer using it.

The cross spider is launched onto a special frame, fed, and the spider weaves its web based on this frame. Then air is pumped through a frame with a net, and the thinnest web perfectly captures the microbes that are in the air. This method of air analysis has been recognized as the most effective of all existing in the world.

IN folk medicine Since ancient times, spider webs have been used to disinfect open wounds. Research has confirmed that spider webs kill pathogenic bacteria, and with its help, drugs have been developed that are harmless to animals, but deadly to all kinds of bacteria. As you can see, the cross spider is extremely useful for humans, in every sense.

Cross spiders are a genus of araneomorph spiders that are part of the orb-weaver family. There are more than one and a half thousand species of cross spiders in the world fauna. They can be found in all corners of Europe. 15-31 species live in the CIS countries.

The cross spider prefers to settle in forests, bushes, gardens, neglected groves, especially near water bodies, as well as in buildings. His favorite place habitat - the crowns of trees, between the branches of which he weaves his trapping nets. Their leaves serve as a refuge for him. It happens that the web of a cross spider can be seen under the eaves or in the window frames of abandoned buildings.

The crossbird can be recognized by the white spots on its abdomen, which in combination form a pattern similar to a cross with four ends. The common cross spider has a yellowish-brown color, sometimes with blackish tints. Brown rings stand out in contrast on his legs. Depending on the environment The color of the spider can change, which allows the spider to camouflage itself in anticipation of prey.

The cross spider is a predator. Nature gave him all the equipment necessary to kill victims. The most common victims are different types flies All the spider's jaws end in a segment that looks like a sharp and movable claw. At the base of the jaws there are special glands that produce poison. As soon as the jaws pierce the body of the victim, a killing poison is injected into it through the holes of the claws.

How to Avoid a Cross Spider Bite

If a person tries to touch a cross spider, it immediately runs away and hides. In most cases, the cross bites a person only when the latter manages to pick it up. Therefore, to protect yourself from a spider bite, it is enough to follow a few simple recommendations.

Firstly, when stopping for the night in nature, carefully close the entrance to the tent.

Secondly, carefully check your bed before going to bed, as well as your clothes and shoes in the morning.

Thirdly, be careful around symmetrical and delicate spider webs. Near them is usually a female, waiting for her prey.

Fourth, be vigilant in old abandoned premises

Fifthly, be careful during gardening and gardening work.

Sixth, when you find a cross, do not try to touch or pick it up. Do not allow children to play with it.

Consequences of a spider bite

It is worth noting that any type of spider is a priori poisonous. All arachnids are natural predators and use their venom to obtain food and for defense purposes. The poison of the cross is a slightly cloudy, colorless, viscous liquid with hemolytic properties.

The poison of the cross has a toxic effect. The thermolabile hemolysin in its composition destroys the red blood cells of rabbits, rats, mice, and humans. For red blood cells guinea pig, horses, sheep, dogs, it has no effect. The thermostable neurotoxic element of the venom has Mr~1000.

The venom neurotoxin is involved in blocking synaptic transmission through acetylcholine and glutamate synapses in vertebrate and invertebrate animals. Plus, the poison promotes the initial excitation of receptors, which are characterized by sensitivity to glutamate and aspartate, and ensures subsequent desensitization. And if the effect of poison on the synapses of vertebrates is reversible, then the effect on the synaptic apparatus of invertebrates is irreversible.

Cross spider chelicerae can cause damage human skin only in those areas where it is very thin. Its bite can be compared to a bee sting. At first there is a feeling of being pricked by a thin needle. It often happens that a person does not notice the bite at all.

After a bite, only local toxic effects are observed. A small amount immediately appears on the affected area. White spot, which does not exceed the size of a five-kopeck coin. The spot usually has pink or red edges. After 5-20 minutes the following symptoms begin to develop:

• headache
• weakness in the body
• painful sensations, aches in the joints
• colic and burning sensation in the bitten area
• subcutaneous hemorrhages.

So far, not a single fatality has been reported from a cross bite. However, after recovery, in some cases, necrosis of the soft tissue is observed in the place where the poison was injected into the skin. The spider's body contains eperotoxin, a special concentration of which is observed during egg laying. This toxic product is absorbed and eliminated from the human body within a day. Swelling remains at the site of the bite for several days.

What not to do if you are bitten by a spider

Do not cauterize the affected area. The bite of the cross does not have serious consequences, and in this way you only further injure yourself.

You should not cut the bite site for the same reasons as described above.

Do not rub or scratch the wound, as this can lead to infection.

What measures can you take if you are bitten by a spider?

Although contact with a cross does not threaten the victim with death, it is still worth providing him with timely first aid. The detailed algorithm of actions outlined below will help you with this.

1. Wash the injured area under running water and soap to avoid potential infection of the wound.

2. Apply a cold compress, ideally ice, to the puncture site.

3. For a headache and a slight increase in body temperature, take the same paracetamol or some other drug with a similar effect.

4. With the development of mild allergic reaction Take any over-the-counter antihistamine.

If a child is bitten by a cross spider, or if symptoms rapidly develop and the condition worsens, consult a doctor immediately.

Interesting facts about cross spiders and their bites

• If spider venom has a local toxic effect on the human body, then its web, on the contrary, helps to destroy pathogenic bacteria. It has long been used in folk medicine to disinfect open wounds.
• The toxic substance eperotoxin is even contained in the eggs laid by the female cross.