The crusader spider is dangerous to humans. A dangerous neighborhood is a spider with a cross on its back. This type of spider has its own external differences.

24.10.2019

The crusader spider is distinguished from its fellows by its impressive size. The length of the females is more than 2 cm, while the male is half as long. The larger size of females is necessary for killing the male after mating, and also allows you to safely carry a large cocoon with small spiders on yourself.

How many legs does a cross spider have? Like all arachnids, the insect has four pairs of legs, which are especially sensitive due to the three claws located at the very tips. With them, he clings to the victim.

On the back, the spider is decorated with a cross of small circles of light or light brown color, located on the upper part of the abdomen, which is why it got its name. A black spider with a white cross on its back lives in shady places - forests, groves, and various thickets. If there is enough sun and light, then the insect is lighter, and its chitinous coating burns out from bright rays. In the lower part of the abdomen, there are arachnoid glands that are capable of producing different cobwebs. For hunting - thin and sticky, and for the maturation of small spiders and cocoons - soft and silky.

The body is covered with hairs that function as a tactile organ. The color of the abdomen of the cross spider also depends on the habitat. Ordinary Representative arachnids of the araneomorphic genus have two pairs of dark-colored eyes.

Their vision is poor - blurry objects and outlines. Spider crusaders react to movements around them.

Cross spiders weave a web quite often - one every 2-3 days, as other insects, animals and weather destroy her. Prefers insects, but mainly feeds on flies, aphids, mosquitoes, grasshoppers and others. Active at night. It rests during the day, but keeps a signal thread under its foot. From trapping nets throws out victims that are too large or unfit for a meal. They are distinguished by special voracity - in a day the cross eats insects weighing from itself.

Symptoms of cross bites

He never attacks a person. Bites occur due to the intervention of the latter in the life of an insect.
The bite of a cross spider is accompanied by the following symptoms:

Itching. The bite site itches unbearably due to the neurotoxins and hemotoxins contained in the venom of the cross.
Hyperemia of the skin.
Slight swelling, as with.
Pain is more common in children or people with hypersensitivity.

The cross spider is poisonous only for small mammals - mice, rabbits, small dogs and young animals. For an adult healthy person the bite of a spider-cross is not a threat. It is necessary to regularly inspect pets in order to start or a spider on time.

But if a person is prone to various allergic reactions or a child has suffered, then an insect bite will cause mild symptoms:

weakness;
chills;
headache;
increase in body temperature;
swelling and hardness at the site of swelling.

Hemotoxin, which is part of the poison, causes the development of hematoma and subcutaneous hemorrhage.

First aid for a bite

First aid for a bite of a spider-cross consists of simple steps:

Wash the bite site with cool water and soap.
Treat with an antiseptic solution and alcohol.
Apply ice to reduce itching and swelling.
Take an antihistamine to prevent allergic symptoms from developing.
For headaches, an antispasmodic is taken (nosh-pa, drotaverine, etc.).
It is advisable to use anti-inflammatory or antihistamine ointments and creams: bepanten, fenistil, soventol, baneocin and others.

The cross spider contains venom that is rich in eperotoxin, neurotoxin, and hemotoxin. All these substances are excreted from the body within one to two days. If the bitten person does not feel better after this time, contact medical care, as in .

Prevention

When relaxing in nature, avoid beautiful wheel-shaped cobwebs and do not pick up. When sleeping in a tent, you need to close it carefully. If you find a web in the country or at home, you should carefully remove it with a long stick, and throw the spider out into the street with a newspaper or a can. Do not touch it with your hands. You should not kill an insect - this is an amazing specimen that benefits humanity.

Spiders are distributed throughout the globe everywhere, only at the North Pole they do not live. There are more than 30 thousand species of these arthropods in the world, more than 2 thousand species are cross-spiders. On the territory of Russia, there are no more than 2 dozen types of crosses. Like all living creatures, spiders protect themselves from danger using their poisonous teeth. Sometimes people become victims of spiders, and for some, a spider bite turns into serious complications. What kind of insect is a spider-cross, and is it dangerous for humans (see)?

You can meet a cross-spider both in nature and in a person’s home. The spider chooses dark, damp shelters where it is easiest for him to hide. The arthropod leads predominantly night image life, during the day it hides not far from its web. As soon as prey enters the web, the trapping thread begins to vibrate, and the spider immediately rushes towards its victim.

How to recognize a cross

To distinguish the bite of this insect from others, you need to know what a cross spider looks like. The spider owes its name to a mark in the shape of a cross, which is located at the top of its abdomen. The arthropod has a cephalothorax and a round belly of a dark brown color, 8 limbs that are highly sensitive and 8 eyes. The eyes of the spider are located on different sides, which allows the insect to see everything that happens around it. Female crosses have a body length of up to 3 cm, males are much smaller and have a length of about 1 cm.

Arthropods feed small insects(mosquitoes, midges, flies and aphids), which, getting into the spider's web, cause the threads to vibrate. The spider, with the help of sensitive legs, immediately understands that prey has got into the web. The arthropod then kills the captured insect with poisonous teeth. The cross sometimes immediately eats its victim, but if it is full, then it entangles it with cobwebs and hides it in a secluded place.

For breeding, the male spider chooses a female with a web and attaches to her trapping web on the side. Then he begins to send signals to the female so that she notices him. After mating games the male usually dies, and the fertilized female begins to weave a cocoon in order to later lay eggs in it. For some time, the mother carries a cocoon with eggs on her belly until she finds a suitable secluded place for him. Having chosen such a place, the spider hangs a cocoon there, and after a short time, spiders hatch from the eggs.

Spider bite symptoms

Is the spider spider considered poisonous? The arthropod does not pose a danger to large animals and humans; its poisonous substance is only enough to kill mice and rats. However, this does not mean that a spider bite is harmless. A person, as a rule, can suffer from an arthropod attack if he accidentally gets into the web. In this case, the spider can pounce on a person, mistaking him for a victim. Also, for the purpose of self-defense, the cross-spider will certainly bite a person if he tries to catch him and pick him up.

At the site of a spider bite, a small white spot appears, which has a diameter of no more than 5 kopeck coins, the spot is slightly red at the edges. In terms of pain, the bite of the cross is similar to a bee (see). Some people may not notice the skin puncture at all. Edema appears at the site of the lesion, which, depending on the sensitivity of the person to poisonous substance spider, can be quite impressive in size. For allergy sufferers, the cross spider is considered poisonous (see). Symptoms of a bite of a cross are:

burning in the affected area;
body weakness;
redness of the skin;
pain in the limbs;
headache;
heat body;
the skin at the site of the bite hardens.

Attention! Children and people suffering from allergic reactions are most sensitive to the bite of the cross. Allergy sufferers can have serious complications in the form of severe edema, difficulty breathing and impaired cardiac activity. If any serious signs appear, the victim should be taken to a medical facility immediately.

First aid for a spider bite

There were no fatal outcomes as a result of the attack of the cross, but this does not mean that the victim of an arthropod bite does not need help. In such cases, you must do the following:

The bite site should be washed with warm soapy water to wash away the microparticles of dirt from the skin and prevent infection from entering the wound.
It is recommended to apply a cold compress to the affected area, ice or a bottle of water will do. cold water. The cold will help reduce pain and remove the resulting edema (see).
If there is pain in the head or when the temperature rises, it is better for the patient to give a Paracetamol tablet.
If an allergy occurs, the victim should be given an available antihistamine.
People with allergies, after being bitten by a cross, must be provided with complete rest and immobilization. Before the arrival of the doctor, the sick person is heavily drunk with warm liquid.
The bite site should not be burned with hot objects, and even more so the wound should not be cut. These actions threaten the penetration of pathogenic bacteria into the affected surface of the skin and the development of purulent inflammation. Also, the wound should never be combed.

Important! When attacking a cross on a child, you must seek medical help immediately, as spider venom is toxic to young children.

Prevention of bites of the cross

A spider attack can be prevented by following simple rules:

going with an overnight stay in nature, you must use by special means to repel insects;
the entrance to the tent should be covered very tightly;
before going to bed, you need to carefully check the bedding for the presence of insects;
after waking up, you should check your personal belongings (clothes and shoes). Spiders can easily hide in human things;
it is better to choose clothes for hiking in nature with long sleeves and trousers;
noticing the web of an arthropod, you need to try not to hurt it. If there is a web, its owner is always nearby;
do not go into abandoned dark buildings such as sheds and barns, spiders love to settle in such places. In the dark, where the spider-cross lives, you can not notice the woven web and get into it with your face straight. In such a situation, the bite of the cross will be inevitable;
children need to be explained that it is impossible to tease and catch arthropods.

The spider has an excellent appetite, in one day he is able to eat as much food as he weighs. If a large or poisonous insect, which is a threat to the life of an arthropod, the spider tries to get rid of it as quickly as possible. To do this, he simply breaks his web, and the insect unsuitable for food falls.

The threads for weaving the web are in special warts located at the bottom of the abdomen of the cross. When the spider shoots out the threads, under the influence of oxygen, they harden and become strong. To weave one trapping net, the cross requires about 20 m of threads.

Since ancient times, people have used the spider's web as an antibacterial agent, so if a spider has bitten, you can attach its own web to the wound.

Conclusion

Crosses do not pose a potential danger to human life, but this does not mean that you can try to catch a spider. Cross bites are quite painful, especially for young children. For people who are prone to allergies, they can result in serious health consequences.

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, common in our area. You can meet a predator everywhere - in the forest, on the field, on the edge, in the park, in the garden, in the yard, outbuildings. Often crawls into the house through cracks in the wall, open windows, doors.

Description and photo of the cross spider

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

How many eyes does a cross spider have - 8. They are 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 short-sighted, sees everything in in general terms- movement, shadow, silhouette. The organs of smell and touch help to navigate in space. They are located on the legs. Once in an unfamiliar place, the spider gently feels the space initially with its paws, and then moves.

What a crusader looks like depends on the species. The structure of the body is not different, but the color is different.

The meadow cross lives in places with humid air, a warm climate, and dim light. Painted in brown, yellow, red tones. On the belly on the upper side are white spots in the form of a cross. Thanks to this identification mark all species of araneus are called crosses. Meadow predator on the grass, preys on small insects.
The forest cross differs from the garden, meadow in a darker color. The body is dark brown with white stripes. On the abdomen, a characteristic white or brown sign of the cross is clearly visible. Paws are long. The largest cross in Russia. The size, together with the span of the legs, reaches 4 cm.
The Far Eastern cross is different large sizes. Habitats - forest, field, meadow. Color brown with different shades. The cross on the abdomen is white or yellowish. Weaves the largest web, which reaches a diameter of 2 m. Even frogs, toads, and snakes can get entangled in strong networks.
Orange or yellow spider with a cross on his back - an ordinary crusader living in the shady places of the forest, field, meadow, garden. Araneus angulatus is a rare species listed in the Red Book. Body size about 18 mm.
A predator with a red cross on its back is a kind of meadow cross. Bright spots scare off 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 the fields, rarely approaches a person’s house. Outwardly, it resembles a tegenaria.

What a cross looks like depends on the species, but distinguishes them from other representatives of arachnids by a characteristic pattern on the back in the shape of a cross. Hence the name came from.

Where does it live

The species is distributed throughout Europe, some species live in North America. Favorable living conditions are high humidity, high temperature, no direct sun rays. Ideal places habitat is coniferous forest, swamps, edges, hedges. Less often they settle in meadows, fields, gardens, kitchen gardens, outbuildings, residential buildings. In Russia, the CIS countries there are about 30 types of crosses.

On a note!
Once in a person's house, the spider chooses places away from noise and light. Occupies the corners at the top of the room, below 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 out into the street, poison the "living creatures".

Lifestyle

Common cross spider - resident wildlife, but under certain circumstances . It leads a nocturnal lifestyle, during the day it sits motionless in a shelter or on a web of cobwebs. He weaves it at night. From the leaves he makes a shelter for himself, between the branches he builds trapping nets.

Experts managed to find out how a 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 the threads. The radius of the web of a large Far Eastern cross reaches 2 m.

Interesting!
At night, the female weaves nets; during the day, the victim is caught in her. The damaged areas are eliminated by the spider, and new coils are formed in place. natural enemies are birds, but with the onset of darkness their activity decreases. The crossbar can work quietly.

The lifespan of a spider is theoretically 2 years. AT vivo it is somewhat shorter. How long does a cross spider live in quality pet depends on proper care. Quietly lives up to 2 years.

Nutrition

The main diet is insects. different sizes. Flies, wasps, hornets, grasshoppers, locusts, caterpillars, butterflies come across in the spider's trapping webs. Snakes, frogs, toads, and mice get entangled in large, strong webs.

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

reproduction

The mating season begins at the end of summer. The female waits for the male on her web, feels his approach by the fluctuation of the nets. After fertilization, weaves a cocoon, lays up to 250 eggs inside. Carries with him, then leaves in a secluded place. In this state, the young hibernate. Spiderlings 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, acquire a characteristic color. By the end of summer they become sexually mature. Caterpillars serve as food for young animals.

On a note!
How adult spiders hibernate - they hide in the crevices of walls, utility rooms, forest litter, tree hollows. They show activity with an increase in air temperature in the spring.

Poisonous or not crusader

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

The crusader is not dangerous to humans. At the sight of people, the spider tries to hide unnoticed. However, in the event of a threat to own life can bite. 2 remains on the body small spots. Initially, there is pain, burning. The next day there is suppuration. In people with weakened immune systems, children after the general state of health worsens. There is weakness, nausea, headache, dizziness, discomfort in the abdomen. The condition returns to normal in a few days.

The spider-cross catches its prey with the help of a web. The spinning apparatus of spiders consists of external formations - arachnoid warts - and internal organs - arachnoid glands. Three pairs of arachnoid warts are located at the posterior end of the abdomen. Each such wart is riddled at the end with a hundred tiny holes. A drop of sticky liquid flows out of each hole, which, when the spider moves, is drawn into the thinnest thread. These threads merge into one and quickly thicken in the air. The result is a thin but strong thread. Such a sticky liquid is secreted by numerous spider glands located in the back of the abdomen. Their ducts open on arachnoid warts.

To form its trapping web, the cross spider first attaches the thread in several convenient places, forming a frame for the web in the form of an irregular polygon. Then it moves to the middle of the upper thread and, going down from there, draws a strong vertical thread. Further, from the middle of this thread, as from the center, the spider draws the threads in all directions, like the spokes of a wheel. This is the basis of the entire web. Then the spider begins to draw circular threads from the center, attaching them to each radial thread with a drop of adhesive. In the middle of the web, where the spider itself then sits, the circular threads are dry. Other threads are covered with droplets of a very sticky liquid and therefore always sticky. In this network, there are over 100,000 such droplets-nodules. Insects stick to them with wings and paws, flying on the net. The spider itself either hangs head down in the center of the web, or hides to the side under a leaf. In this case, he stretches a strong signal thread to himself from the center of the web.

When a housefly enters the web, the spider, sensing the trembling of the signaling thread, rushes out of its ambush. Sticking claws with poison, the spider kills the victim and secretes digestive juices into her body. After that, he entangles a fly or other insect with a web and leaves it for a while.

Influenced by secreted digestive juices internal organs spider prey are quickly digested. After some time, the spider returns to the victim and sucks out all the nutrients from it. From the insect in the web, only an empty chitinous cover remains.

Making a trapping net is a series of interconnected unconscious actions. The ability to do so is instinctive and inherited. This is easy to verify by following the behavior of young spiders. When they emerge from the eggs, no one teaches them how to make a trapping web, but the spiders immediately weave the web correctly.

The structure of the body of the spider-cross

The cross-spider is an ordinary inhabitant of our forests. It is also easy to meet him in your yard or even in your house. This spider, which has a yellowish-brown or almost black color, is very easy to recognize by a white cross-shaped spot on the dorsal side of the body. Due to this feature, it is also called a cross. Its coloration has a protective value, it makes it invisible in the twilight among dense shrubs, between tree trunks.

In some structural signs, the spider-cross resembles crayfish, but at the same time differs from it in a number of features associated with a different lifestyle. The class of arachnids changed under the influence of the transition from aquatic to terrestrial lifestyle. Like crayfish, the body of the arachnid class (spider-cross) consists of two sections: the cephalothorax and abdomen. But his abdomen is strongly swollen and not dissected. Unlike crustaceans, there are no antennae on the head of the cross-spider. The spider-cross, like the tick, does not have compound eyes. On the upper side of the head are eight simple eyes, and on the lower side, around the mouth, two pairs of jaws. Spiders are predatory animals. They feed mainly on insects. With the front pair of jaws, the spider kills prey. Poison glands are located at the base of the jaws. When the claws that end in the jaws pierce the prey, the poison flows into the wound and kills the victim.

With the second pair of jaws, the spider gnaws its prey. Behind the jaws are four pairs of long walking legs. Like crayfish, spider legs are made up of individual segments. Each leg ends in serrated claws so the spider can run on its web without becoming entangled in it. The claws also help the spider to weave its web. Unlike crayfish, the spider brooch has no limbs.

Virulence

The spider-cross is poisonous, but not deadly to humans. As a rule, crosses are not able to bite through human skin, but if this does happen, then a red spot forms at the site of the bite and a slight necrosis of tissues from the action of the poison.

Treatment for a bite

Apply cold compresses to the site of the spider bite.

Spiders are a genus of araneomorphic spiders that is part of the orb weaver family. In the world fauna, there are more than one and a half thousand species of cross-spiders. They can be found in all corners of Europe. 15-31 species inhabit the territory of the CIS countries.

The spider-cross prefers to settle in forests, shrubs, gardens, neglected groves, especially near water bodies, as well as in buildings. His favorite habitat is 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 also be seen under the eaves or in the window frames of abandoned buildings.

The cross is recognizable by the white spots on the abdomen, which in combination form a pattern similar to a cross with four ends. common cross spider has a yellowish-brown color, sometimes with blackish tints. On his legs, brown rings stand out in contrast. Depending on the environment The spider's coloration can change, allowing the spider to camouflage itself while waiting for prey.

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

How to Avoid a Spider Bite

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

First, when staying overnight in nature, carefully close the entrance to the tent.

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

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

Fourth, be vigilant in old abandoned premises

Fifth, be careful during summer garden and garden work.

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

Consequences of a spider bite

It is worth noting that a spider of any kind is a priori poisonous. All arachnids are natural predators and use their venom for food and protection. Spider venom 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 erythrocytes of rabbits, rats, mice, and also humans. For erythrocytes guinea pig, horses, sheep, dogs it has no effect. The thermostable neurotoxic element of the poison has Mr~1000.

The venom neurotoxin is involved in blocking synaptic transmission through acetylcholine and glutamate synapses in vertebrates and invertebrates. Plus, the poison contributes to the initial excitation of receptors, which are characterized by sensitivity to glutamate and aspartate, and provides subsequent desensitization. And if the effect of the poison on the synapses of vertebrates is reversible, then it acts irreversibly on the synaptic apparatus of invertebrates.

Spider spider chelicerae can damage human skin only in those areas where it is very thin. Its sting can be compared to the sting of a bee. First, there is a feeling of a prick with 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. On the affected area immediately appears a small White spot, which does not exceed the size of a coin of five kopecks. The patch usually has pink or red edges. After 5-20 minutes, the following symptoms begin to develop:

headache
weakness in the body
pain, joint pain
colic and burning sensation in the bitten place
subcutaneous hemorrhages.

So far, not a single one has been registered with a bite of a cross lethal outcome. However, after recovery, in some cases, soft tissue necrosis is noted at the site where the poison was injected into the skin. The body of the spider contains eiperotoxin, a special concentration of which is observed during egg laying. This poisonous product is absorbed and excreted from the human body in a day. At the site of the bite, swelling persists for several days.

What not to do when bitten by a cross spider

Do not burn the affected area. The bite of the cross has no serious consequences, and thus you only further injure yourself.

You should not dissect 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 be taken when bitten by a spider-cross

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

1. Wash the injury site under running water and soap to avoid potential infection of the wound.

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

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

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

If a cross spider has bitten a child, or if there is a rapid development of symptoms and a sharp deterioration in the condition, 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, contributes to the destruction of pathogenic bacteria. It has long been used in traditional medicine for the purpose of disinfecting open wounds.
The poisonous substance eiperotoxin is found even in the eggs laid by the female cross.