Spider with a yellow belly and a cross. How to recognize a cross-spider and how dangerous is it? What is the appearance of a cross spider

Millions of different spiders live in nature, killing entire armies of insects that are dangerous both for humans and for their homes.

And if not for these arthropods, then the number of mosquitoes, moths, aphids and other insects would be much larger, which would cause great discomfort to people and animals.

What it looks like: description, internal and external structure of the body

One of the most common representatives of the family of round-web spiders is the cross-spider, with more than 1000 varieties. Consider the brightest representatives of this family, which are the main characteristics of the body structure.

Common cross (Araneus diadematus)

This type of cross is a small spider.

Its external characteristics are as follows:

• the body of an adult male reaches a maximum of 1.1 cm, females are larger, specimens up to 4.0 cm can be found;
• the body cover consists of a strong shell of a yellow-brown hue, which changes during the molting period;
• wondering how many legs an ordinary cross has, you need to know that the spider has 8 legs, each of which plays its role in the life of an arthropod;
• the sense organs are well developed. The spider has a good sense of smell and taste, thanks to the hairs that cover the entire body, it easily captures even the smallest fluctuation or vibration;
• four pairs of eyes, each of which is turned in different directions, create an extensive horizon.

Important! Despite the large number of eyes, arthropods of this species are short-sighted. They can only see shadows and outlines of large objects.

Angular (Araneus angulatus)

Another type of spider-cross, which is listed in the Red Book in many countries.
External differences are represented by the following indicators:

• females reach small sizes, a maximum of 1.8 cm, but they are still larger than the male, whose length is only 1.2 cm;
• they do not have a cross, instead, small humps in the amount of 2 pieces, which are located in the abdomen;
• the whole body is dotted with light-colored hairs;
• the oral apparatus is located on the cephalothorax;
• eyes count 8 pieces;
• there are 4 pairs of legs on the body.

In general, the parts of the body and the respiratory organs are no different from other representatives.

Marble (Araneus marmoreus)

This type of spider has its own external differences:

• has significant sexual dimorphism. Females grow much larger than males. Their length is up to 18 mm, spiders grow up to 8 mm;
• these arthropods are endowed with an extensive range of colors and patterns. However, the most common is an orange belly and a black pattern. It is this variation that gives the species its name.

The remaining organs, as well as the digestive and respiratory systems, are the same as those of other spiders of this species.

Where does it live and how long does it live

Habitat - wet and damp terrain. The greatest probability of meeting with him can occur in places where a large number of trees grow, where they stretch their web, as well as along the banks of reservoirs and even in the attics of various buildings.

Did you know? 2.5 billion years ago, the first spiders appeared on Earth, which gave life to more than 30 thousand species of spiders that live almost everywhere today.

More than 30 species of spiders live in Russia and the former CIS countries, including Ukraine. This species of arthropod is a hermit predator, and the main feature of its behavior is an extremely negative attitude towards its own kind. At night, these arthropods weave their trapping webs, and during the daytime they hunt their prey.

What does it eat

The main diet of the spider are small insects. The female during the day absorbs food in an amount equal to her weight. When an inedible insect enters the web, the spider gets rid of it by breaking the threads.
He also tries to avoid flies and wasps, which can lay eggs on other animals. Hunting occurs in two ways: in the center of the web or from a nearby shelter.

The predator is not able to immediately consume food, so it quickly injects aggressive juice into the caught prey, places the prey in a cocoon and waits for the victim's insides to turn into a nutrient solution. This process takes about 1 hour, after which the spider sucks out the prey, and the cocoon remains.

Spider spider web

All the webs that spiders weave are no different from one another, since the ability to weave a web is inherent in these predators at the genetic level. Only females are engaged in weaving such beautiful, intricate patterns.

Did you know? In microbiology, the web is used as the thinnest optical fiber to identify the composition of the air located in the atmosphere.

The web has strictly 39 radii and 1245 points of their attachment to the spiral, which, in turn, consists of 35 turns. The threads that make up the web are light, but at the same time they are very strong - they are used by the inhabitants of the tropics for weaving nets and fishing gear. In addition, the threads are very elastic.
In the process of arranging her creation, the female uses two types of threads. The base and radii are woven from dry fibers of a strong structure without a sticky coating and stretched between the branches.

Then the spider begins to weave the threads, which are located from the center to the edges, and the spiral thread, which will be the basis for the trapping spiral. After the work done, the spider lays a web with an adhesive base from the center of her creation.

The spiders themselves move only along dry threads, so they do not stick to their trapping webs. It takes about one hour for the spider to weave the entire web.

poisonous or not

The venom of the brown cross contains heat-labile hemolysin, which has a negative effect on blood cells.

However, its dose is so small that it can only harm small animals. For humans, a spider bite is not dangerous, but minor discomfort may occur if you are allergic to animal bites.
At the site of the bite, there is a quickly passing minor pain and itching. To quickly relieve these symptoms, it is necessary to wash the affected area of ​​\u200b\u200bthe skin with soap and apply something cold, ice if possible, then apply an ointment to relieve inflammation.

Important! The spider never attacks first - a bite is possible with accidental contact.

Reproduction and offspring

The mating season for spiders takes place in August. During courtship, the male, in order not to become a victim, carefully approaches the edge of the web, pulls the strings with his paws and waits until the female responds in kind. Then mating occurs, after which the male dies.

The female, immediately after mating, begins to weave a cocoon, in which eggs will be placed in the future. The cocoon will stay with her for a while, and then she will hide it in a secluded place.

In autumn, a spider lays an average of 500 eggs in a cocoon, which are completely stored in it until spring. After hatching, many small spiders die as a result of high competition and attacks from relatives.
They are faced with the acute issue of survival, and for this they need to leave the mother's cocoon as soon as possible. Spider legs are small and weak. Because of this, they move on the web, gliding under the influence of the wind like on a magic carpet.

When the wind subsides, the web falls to the ground, and the spider leaves it, starting a new life. If the site turns out to be successful, then with the help of its nets it will be able to catch up to 400 insects throughout the day. By the beginning of summer, the spiders are already capable of mating, and by the same time the spider that gave them life dies.

Did you know? With the help of a web, a cross can overcome about 400 km of the way.

As can be seen from all of the above, the opinion of many that all spiders with crosses on their bodies and villi are dangerous to people is erroneous. However, despite this, you should not tempt fate and try to stroke or pick up this arthropod.

Cross spiders are a genus of the class of arachnids with about 2 thousand species. They are widespread and are typical representatives of their class.

Crosses live in forests, gardens, meadows. Weave a web between branches, on buildings, etc. They feed on small insects.

The size of representatives of cross-spiders is from 1.5 to 4 cm in females and about 1 cm in males.

The chitinous cuticle of cross spiders is quite thin. The body is subdivided into a small, slightly elongated, non-segmented cephalothorax and a large, in comparison with it, non-segmented, rounded abdomen. A lighter pattern in the form of a cross is formed on top of the abdomen. Hence the name of these spiders.

There are four pairs of walking legs on the cephalothorax. In front of them are chelicerae (jaws) and pedipalps (mandibles). With the help of the first, the cross-spider kills the victim. Their terminal segments are transformed into claws, in which ducts of poisonous glands open. The poison has a paralyzing effect. Pedipalps are used to hold the victim, turn it over, and they also have many organs of touch.

At the end of the abdomen there are six arachnoid warts (three pairs). They open the ducts of the spider glands, which can be about 1000. Cross spiders secrete various types of webs. Some are sticky, others are more durable. When released, the web hardens in air, turning into a fairly strong thread. Spiders weave trapping nets, shelters, cocoons from the web, bind the victim with it. The trapping web of the spider-cross consists of a strong polygonal base and radial supports and sticky concentric circles. From the central part of the network, a thread departs to the spider's shelter. The oscillations of the web when the victim hits it are transmitted along this thread to the spider, and it crawls out of the shelter.

The spider-cross injects into the victim not only poison, but also digestive juices, which break down its tissues, turning it into a liquid slurry. Extraintestinal digestion lasts about an hour. The spider can only eat liquid food, which is completely digested inside its digestive system. The suction of food occurs due to the muscular pharynx. There is a stomach, a branched midgut, into which the ducts of the liver open. Here, nutrients are absorbed into the hemolymph (arthropod blood mixed with lymph). Undigested residues go into the hindgut and are excreted through the anus.

The circulatory system is characteristic of all arthropods: open. On the dorsal side of the abdomen there is a tubular heart. From the heart, the hemolymph is pushed through the vessels to the front of the body, then it pours into the spaces between the organs and flows in the abdominal direction, where it is enriched with oxygen. After that, the hemolymph is again collected in the vessels and sent to the heart.

The respiratory system of the spider-cross consists of a pair of lung sacs and trachea. The lungs are located in the anterior part of the abdomen, contain many leaf-like folds, in which a lot of hemolymph flows. Tracheas are thin bundles of tubes that run through the body. They do not need hemolymph as an intermediary for the transfer of oxygen.

In cross-spiders, the excretory organs are represented by malpighian vessels, whose ducts open into the extension of the hindgut (cloaca), and coxal glands, the ducts of which open at the base of the first pair of walking legs.

In the ventral nerve chain in cross-spiders, the ventral ganglia merge. There are 8 simple eyes, which, like all arachnids, see poorly. The organs of touch, represented by sensitive hairs, are well developed. There are organs of smell and chemical sense.

Spider-spiders have pronounced sexual dimorphism. Females are larger and kill males after fertilization. The sex glands are paired, their common duct opens on the abdomen. The male delivers his sexual products to the female with the help of pedipalps. After fertilization, the female spins a cocoon using a soft silky web. Then it lays eggs in a cocoon, in which small spiders develop, i.e., the development of cross-spiders is direct.

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. An ordinary representative of arachnids of the araneomorphic genus wears two pairs of dark eyes.

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

Spiders weave a web quite often - one every 2-3 days, as other insects, animals and weather conditions destroy it. 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:

1. Itching. The bite site itches unbearably due to the neurotoxins and hemotoxins contained in the venom of the cross.
2. Hyperemia of the skin.
3. Slight swelling, as with.
4. 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 cross spider does not pose 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:

1. Wash the bite site with cool water and soap.
2. Treat with an antiseptic solution and alcohol.
3. Apply ice to reduce itching and swelling.
4. Take an antihistamine to prevent allergic symptoms from developing.
5. For headaches, an antispasmodic is taken (nosh-pa, drotaverine, etc.).
6. 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, then seek medical help, as with.

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.

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 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 distinguished by its large size. Habitats - forest, field, meadow. The color is 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.
• An orange or yellow spider with a cross on its back is an ordinary crusader that lives 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 conditions for existence are high humidity, high temperature, lack of direct sunlight. Ideal habitats are coniferous forests, 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

The common cross spider is a resident of the wild, 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. Birds are natural enemies, but their activity decreases with the onset of darkness. The crossbar can work quietly.

The lifespan of a spider is theoretically 2 years. Under natural conditions, it is somewhat shorter. How long a spider spider lives as a pet depends on the correct care. Quietly lives up to 2 years.

Nutrition

The main diet consists of insects of various 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.

There is no internal digestive system, the liquefaction of food occurs externally. 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 case of a threat to their own lives, they can bite. There are 2 small spots on the body. 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 cross-spider is a representative of the most common species, which is found in almost all regions except for the northern and southern latitudes. It prefers places with high humidity and is most often found in gardens, fields, among shrubs growing near water bodies, as well as in groves and forests. It can also live on the eaves of buildings and on the facades of buildings.

Characteristic

The spider-cross, or crusader, got its name from, which, as you can see in the photo, is formed from white spots. The abdomen of the arthropod is colored brown and has a teardrop shape. The cross has 8 legs, on which supersensitive organs of smell are located. There are 8 eyes on the head, they are directed in different directions, which makes the view as wide as possible.

It is interesting! Cross spiders have very poor eyesight - they see only blurry outlines of objects. And the sense organs on their paws help them to learn and interact with the outside world!

The male cross spider looks the same as the female. The only difference is the sizes. So, females are somewhat larger than males and their sizes can be from 16 to 25 mm, the body size of a male is about 10-11 mm. Throughout their lives, these arthropods molt several times, and this happens at regular intervals.

Nutrition

Crosses are hunters who are most active at twilight and at night. During the day, they prefer to sit in secluded places. Their diet contains:

• flies;
• butterflies;
• mosquitoes;
• vile, etc.

During the hunt, the crusader spider is located in the center of its web and freezes. From the outside, it looks like he's dead. But as soon as the victim gets into the net, the hunter reacts with lightning speed. He quickly runs up to the entangled insect, pierces his body with his sharp claws, which are located on the front pair of legs, and injects paralytic poison. After a while, the caught victim freezes. At the same time, in different situations, spiders either immediately eat their prey, or leave it in reserve.

On a note! The fact that someone is in the web, the spider learns with the help of its paws - the victim moves, trying to get out, and creates a vibration that the cross feels!

The spider-cross eats quite a lot - the total amount of food absorbed per day is approximately equal to its body weight. And at one time he is able to eat about a dozen insects. For this reason, he spends almost all his time hunting, constantly being in the web and waiting for the next victim. A small part of the day is allotted for rest, but even during this period, the signal thread is necessarily tied to one of the hunter's legs.

On a note! Not all insects are included in the diet of the spider-cross. If a victim with an unpleasant odor, someone poisonous or too large gets into the web, then the hunter prefers in this case to let the unwanted guest go. He bites through the restraining threads and lets go!

reproduction

Young males during the spring and summer are mainly engaged in weaving webs and hunting, trying to provide themselves with normal food. Closer to the mating season, they leave their shelters and move from place to place in search of a female. At this time, they eat extremely poorly, which explains the significant difference in mass between them and spiders.

After the male finds the female's web, he makes several attempts to inform her of his appearance - he carefully steps on the edge, causing vibrations. The female immediately takes off and tries to catch up with the male, thinking that this is another victim. And the male, in turn, flees along his thread, which he prudently lowers down in advance. This continues until the spider understands who exactly came to visit her.

Immediately after mating, the spider tries to hide faster. However, it is possible for units - the most agile. Most die from the poison of the female. This period falls approximately at the end of summer or the beginning of autumn.

The fertilized female lays eggs. Eggs, of which there can be about 300-800 pieces, she places in a cocoon tightly woven from cobwebs and wears it for some time. Then the spider finds a suitable hiding place, where she leaves the clutch. Often, such a place becomes the bark of a tree lagging behind the trunk, cracks in the wood, fallen leaves, etc. The eggs are stored there until spring. At the same time, in the cocoon, the future offspring is in absolute safety - it is warm in it and it does not get wet.

With the onset of heat, small spiders appear from the eggs.

After the birth, young crosses need enough food, but the territory where they first saw the world is not always able to feed them. Therefore, it is important for spiders to leave this densely populated area as soon as possible, otherwise many of them risk being eaten by their own brethren or simply die of hunger. However, these arthropods are not capable of moving independently over a long distance, since their legs are very poorly developed. Often they are carried by a fair wind - the spider waits for windy weather, clings to its web and thus flies from place to place.

It is interesting! The web helps the cross spider to overcome very impressive distances - sometimes about 400 km!

Given the above, it is easy to calculate how long the cross spider lives. In the spring, the young come out of the eggs, and in the fall they already mate. Males in most cases die immediately after they fertilize the female, and spiders a little later - they spend several weeks near the hidden cocoon and, having fulfilled their parental duty, die before winter comes. It turns out that not so much is allotted to the cross by nature - only 6-8 months.

Toxicity

Is the cross spider dangerous for humans? Its poison is toxic to us, and after about five minutes after the bite, the following unpleasant symptoms can be felt:

• severe headache;
• slight increase in body temperature;
• slight weakness;
• discomfort in the joints;
• itching and tingling at the site of the bite;
• subcutaneous hemorrhages are possible.

On a note! Often, after a bite, only a local reaction occurs, which manifests itself in the form of a reddened and somewhat hardened edema. But sometimes the consequences can be more serious. In this case, it depends on the immune abilities of the human body!

The bite of a cross spider is not fatal, however, despite this, it is advisable to avoid contact with it. If he did bite you, then, first of all, the affected area should be thoroughly washed with soap, which will help prevent additional infection. Next, something very cold should be applied to the bite site, ice if possible, and treated with an anti-inflammatory ointment.

Important! If a cross spider has bitten a child, then calling an ambulance is mandatory!

In order to avoid contact with the cross spider while relaxing in nature, it is imperative to close the tent at night, and if it has windows, then mosquito nets must be placed on them. In the evening, be sure to inspect your bed, and it is advisable to take out all the blankets and blankets and shake them well. When walking through the forest, always bypass the woven cobwebs, and if you notice a cross very close, then in no case take it in your hands.

Similar rules apply to staying at a tourist base and even in the country. Upon arrival, all rooms should be inspected for the presence of a symmetrical web, and if one is found, then it must be carefully removed immediately with some long object. In this case, it is advisable to protect your hands with gloves.