What does a black widow spider look like. Black widow - external signs, lifestyle and how dangerous karakurt is for a person. Black is always in fashion: what does a spider look like

There are many really outlandish, sometimes pretty, sometimes cowardly, and sometimes very dangerous specimens in the wild. The latter include black widow spider.

These insects are unusual, possessing an original appearance and suffering from cannibalism. These are the most poisonous and dangerous spiders North America. Their bite is very dangerous, but fortunately it can not always be fatal.

Description and features of the black widow

Where did this seemingly harmless animal get such a bright and frightening name from? It's all about deceit female black widow spider. Having received from her partner the offspring necessary for the continuation of the family, she immediately eats it.

Scientists suggest that she does this because of the lack of protein, which she needs so much when laying eggs. In any case, it is precisely such a sad picture that always occurs in laboratory conditions, where it is impossible for a male to hide from a female.

In nature, sometimes males still manage to carefully sneak up, fertilize the female and stay alive. It is very interesting to watch the dance of the spouse male black widow. He is trying to dance a chic spider dance to make it clear to the lady of his heart that he is not food, but her half.

Cannibalism haunts the black widow spider from the very beginning of life. Of the thousands of eggs laid by the female, only a few manage to survive. All the rest are eaten by their own kind still in embryos.

Such a fierce name has no effect on people. Of all descriptions of black widow spiders it is known that to some extent even a timid and shy creature. In fact, humans are more of a threat to them than they are to humans. They rarely bite people, and then for self-defense.

Black widow spider in the photo- an amazingly beautiful sight. In real life, they look even more attractive and beautiful. The body of the insect is painted in a rich black glossy color. A red spot is visible on the back of the female.

Sometimes a young female has a white border on red spots. Males at the beginning of their lives have a white or yellow-white body. It acquires dark shades after several links. The adult male has a dark brown body with light sides.

The insect, like many spiders, has 8 limbs. They are much longer than the body itself. If the body reaches 1 cm in diameter, then the legs of the spiders reach up to 5 cm. Spiders have 8 eyes. They are placed 4 in 2 rows. The middle pair of eyes has the main function. With the help of lateral eyes, insects distinguish between light and moving objects.

In fact, even with such a large number of eyes, a black widow cannot boast of perfect vision. The insect determines its victim by the vibration of the web, into which it was not lucky enough to fall. They weave very strong webs. It is sometimes difficult to get out of them even for mice.

Black widow spider bite poses a great danger to the elderly and young children. This part of the population has a weakened immune system.

Only a timely introduction of an antidote can prevent a possible disaster. So after the bite poisonous black widow spider do not hesitate, but it is better to immediately call an ambulance.

But from observations it is known that these insects never attack first. This happens during defense or by accidental contact. In those places where a large accumulation of these insects is noticed, they can even make their way into human habitation.

There were frequent cases when they bit a person while in his shoes. Therefore, in such regions, caution should become a habit for people.

An adult male does not have such a sharp disposition as a female and he has practically no poison. But he is able to paralyze an insect that has fallen into his territory. Insects become especially aggressive from April to October.

Spider lifestyle and habitat

This dangerous insect can be found anywhere in the world. The spider is especially widespread in Europe, America, Asia, Australia, Africa. Black widow spider in Russia until some time was an exclusively exotic insect.

After all, he prefers a hot and temperate environment. But recently, these spiders have been seen not in a single copy in places along the Urals and in the Rostov region. The black widow spider dwells in dark places, in dense thickets, in sheds, basements, toilets, rodent burrows, in dense foliage of grapes.

They lead a solitary nocturnal lifestyle. During the day, insects prefer to hide. In general, they try to always remain unnoticed. As soon as the black widow feels a serious danger, she falls out of the web and takes on an immovable pose, making it clear with her whole appearance that she is not alive.

Without its strong web, the insect is helpless and clumsy. With the onset of cold weather, spiders approach human habitation. Therefore, a photo of a black widow must be shown to your young children, who are distinguished by increased curiosity and can take an insect in their hands due to their ignorance and negligence.

Feature of the black widow spider Those are his furry paws. The most powerful and with a large number of bristles. With their help, the spider tightens the web of the web over its prey. Recognizing the web of this insect is not difficult. It has a chaotic weave and is mostly placed horizontally.

Black widow spider species

Each specific territory is characterized by one or another type of black widow. In the CIS countries, two species of these insects were noticed - karakurt and white karakurt.

The steppe widow or karakurt is always black in color with scarlet spots on the back and stomach. Sometimes the spots turn yellow or orange. In most cases, these are steppe inhabitants, hence their name.

Their large distribution becomes dangerous for people who are engaged in manual agricultural work and risk being bitten by insects. The males of these spiders are usually smaller than the females. Females, in turn, are a great danger not only to humans, but also to animals.

The strong web of these insects is usually located almost above ground level. But there are these traps for victims on the stems of plants, as well as among the stones, in the gorges.

Karakurt is considered the second most poisonous of all black widows. Most active in summer. It cannot be said that he is more active and prefers to bite his prey first. Usually this happens to him for the purpose of self-preservation.

There is also a brown widow. This is also a species of these insects. The color of such spiders is dominated by brown, and the abdomen is decorated with an orange color. Among all black widows, brown is the safest. Its poison is absolutely not terrible for people.

In frequent cases, the black widow is confused with the red capito. They are the same black color and have a red marking on their back. These insects live in New Zealand. You can distinguish insects by the web, which the capito weave in the form of triangles.

Australian black widow, As the name suggests, it lives in Australia. The female insect is also larger than the male. Australians fear this spider. Its bite causes incredible pain to people, which only disappears if an antidote is administered. Western black widow found on the American continent. She is black with a red spot. Males are pale yellow.

Nutrition

The diet of these insects is not much different from the menu of all other arachnids. Basically, it includes insects that, through their negligence, fall into the web. Their favorite treats are flies, midges, mosquitoes, beetles and caterpillars.

It is interesting to watch how the spider treats its prey. The fact that the "food" is already in place, the spider understands by the vibration of the cobwebs. He gets closer to his victim and wraps his hind legs around her so that she is simply no longer able to escape.

The widow has special fangs, with the help of which the spider injects its victim with a special liquid that liquefies all of its flesh. This causes the victim to die.

Another feature of the black widow is that she can limit herself to food for a long time. Starving spiders can live for about a year.

Reproduction and lifespan

Spiders become sexually mature at 9 months of age. After the male dances, he carefully sneaks up to the female and mates with her. Some males then die from the female herself. Others manage to survive.

A fertilized spider lays eggs. They are stored in a special grayish ball attached to the web. The ball is constantly next to the female until offspring appears from it. From fertilization to the appearance of babies, on average, it takes about a month.

In still very tiny creatures, from such an early time, there is a struggle for existence, in which a strong spider eats a weak one. Such a struggle ends with the fact that not everyone manages to survive. Of the large number of cocoons, no more than 12 babies leave.

Newborn spiders are white. They need to go through several molts in order for the color to darken, and they become visually similar to adults. Black widow females live up to 5 years. In males, things are somewhat sadder with this. In frequent cases, they die from females in the first days of their puberty.

View: Black Widow Spider (Latrodectus)

Family: Tenet spiders

Detachment: Spiders

Class: Arachnids

Type: Arthropod

Subtype: Cheliceric

The size: Approximately 38 mm long (feet 12 mm), 6.4 mm in diameter

The weight: 1 gram

Lifespan: 1 – 3 years

Habitat

This type of spider is distributed throughout the world. They live in regions with a temperate climate, incl. in the US, Southern Europe, Asia, Australia, Africa and much of South America. Can be found in dark, dry hiding places, dimly lit areas such as sheds, garages, basements, closets, hollow tree stumps, rodent burrows, dense vineyard vegetation. They tend to take shelter in warm dwellings in winter. Although the black widow spider was not previously known in Russia, in recent years they have been found in the Southern Urals and in the Rostov region. Migration is explained by an increase in air temperature.

Description

The adult spider is painted black. On individuals, mainly red spots or a long red spot in the form of an hourglass are located. Immature females have red spots with a white outline on the abdomen.

The body length of the spider is about 12 mm, paws - 12 mm. Adult male black widows are half the size of females. Young spiders are painted white or yellowish-white and darken with each subsequent molt. Spiderlings hatch after 2-4 weeks and, like their mother, are cannibals. While in a cocoon, they eat each other for food. Therefore, only 1-10 spiders are chosen to be free.

An important characteristic of the black widow is its shaggy combed paws. A row of strong, curved bristles are located on the hind pair of legs and are used to draw webs over captured prey.

In the southern parts of Russia, as well as in some countries of Central Asia, in Ukraine, in the Mediterranean region and in the Balkans, there is another species from the genus of black widows - karakurt.

Development

The fertilized female lays her eggs in a cocoon of cobwebs, which she fastens near her trapping net. The cocoon itself is a grayish ball with a funnel-shaped exit. The clutch is under the constant control of the mother until spiders appear from the eggs.

Development in the egg takes 2 to 4 weeks. Young offspring, just released from the eggs, immediately enters the struggle for life. Stronger individuals eat the weak, so not everyone survives. As a result, only a small handful of young black widows, often up to 12 spiders, leave the cocoon.

Immediately after birth, the body of young individuals is painted white. And only after a few molts have they darkened enough and will look like adult spiders from the genus of black widows.

Eggs

A grayish silk ball of eggs with a funnel-shaped exit is attached to the web. Each female builds 5 to 15 of these balls, 12-15 mm in diameter, each containing 200 to 900 eggs. These clutches are fiercely guarded by the mother until spiders emerge from them.

Spiders (babies)

Young spiders leave the ball after 10-30 days. Only a handful of them will survive, as black widows are cannibals in the early stages of their lives. They consume other spiders from their brood for food. Elderly individuals die in summer or autumn after laying eggs. The new generation survives through the winter. Surviving spiderlings undergo molting. At first they are white, then orange, and only after a couple of months they resemble adult male black widows. Surviving individuals leave the network. It will take 2-3 months for them to mature, begin to weave their linens and get food.

Interesting! Although the life expectancy of black widow spiders is one year, some female specimens live up to three years. Males are usually only 1-2 months old. These spiders live longer in captivity.

reproduction

The male black widow, before going in search of a partner, weaves a small web, rubs the end of the abdomen against it so that sperm drops appear on it. Then he sucks up the sperm with his sexual organ, the pedipalps, which look like small legs. After that, the male is already ready to meet his partner. He begins to shake the web as a sign that he is ready to perform a vital function. During intercourse, the male uses the pedipalps to carry sperm into the female's body.

Sometimes only one mating occurs, however, the female may store the seed in her body and use it, for example, after a few months. After mating, the female weaves a silk cocoon into which she lays her eggs. After some time, small spiders hatch from the eggs, which are miniature copies of their parents and soon become independent.

Why does a female black widow spider eat a male?

Spider species female Latrodectus mactans(black widow) spends her whole life patching and completing the same web. It feeds, like other spiders, on insects caught in the net. Males, attracted by pheromones, with which the entire web of the female is saturated, find their chosen one and try to make sure that other spiders do not smell her scent. To do this, they begin to destroy everything built by the hard work of the spider: they bite the web, tangle it and cover it with their own thin threads that mask the smell of the female.

For all this, the male takes a lot of time and effort; he has no time to arrange his own networks. Therefore, he does not live long. Its main goal is to fertilize the female; when he succeeds, his resources, as a rule, are already running out. After mating (and even in the process), the male ends up in the jaws of the female; she digests it and thereby provides food for future offspring.

What does a spider eat?

The black widow feeds on flies, moths, and other flying insects, as well as ants, beetles, and even other types of spiders. She makes a chaotic, three-dimensional web, very often with a short “cap”, in which she hides herself, waiting for prey.

The web of males is smaller than the web woven by the female. While waiting for prey, the black widow touches the fibers with its limbs from time to time. When an insect, flying, catches on the sticky fibers of the net, it sticks to them. The spider, through the web, feels even the slightest movement of the victim, who is fighting for his life, so without wasting a moment, he runs out of the shelter and begins to wrap sticky threads around the prey. Then the spider injects poison into the body of the victim, along with saliva containing digestive enzymes, and continues to wrap its web around the paralyzed insect.

Over the next few hours, saliva digests the victim's body, and the black widow sucks out its dissolved contents. The spider's muscular stomach acts like a pump. All that remains of the prey is an empty shell.

Black widow bite

The black widow spider has earned the reputation of a killer, but the number of people who have been killed by its poison is small. According to American statistics, out of 1,291 people bitten by a black widow over 217 years, only 55 died between 1726 and 1943. Probably most of the victims are children or old people, in whom the effect of the poison could cause additional complications. The bite of karakurt causes symptoms similar to angina pectoris and tabes.

The neurotoxin found in black widow venom is 15 times stronger than rattlesnake venom. Black widow bite it is accompanied by instant sharp pain at the site of the bite, and after some time (from 15 minutes to 1 hour), other symptoms begin to appear. First of all, these are severe pains in the abdominal region, due to which the bite of a black widow is often confused with an open ulcer, pancreatitis, or other diseases of the digestive tract. The difference is that pain does not increase with palpation. In addition to pains in the abdomen, pains and cramps in the limbs begin, the patient begins to thrash about the bed and scream, breathing gets confused, it becomes difficult. In addition, nausea, severe headaches, salivation, severe sweating, hyperreflexia, hypertension, paresthesia of the extremities, mild fever can be observed.

With timely medical care, after 2-3 hours the pain subsides, but does not go away completely, and within a few days they can resume with renewed vigor. Full recovery occurs only after a week. But bringing the patient to the hospital on time does not mean saving him; children or the elderly often die due to heart or respiratory failure during the manifestation of the main symptoms.

Peak aggressivenessblack widow spiderfalls from mid-April to October.

Adult male black widows are half the size of females and less dangerous, while young of this species are born white or yellowish, and darken more and more with each molt until they reach puberty and become glossy black.

And remember, in order not to meet face to face with such an unpleasant "lady" as a black widow, you just need to follow some rules:

• if there is a possibility of meeting a spider or you are in its habitat, then you need to dress in such a way as not to leave a single open area of ​​\u200b\u200bthe body;
• in the case of outdoor recreation, make sure that the place of rest and overnight stay is not in the zone of various soil depressions, rodent burrows and cobwebs on plants;
• after walking in the area of ​​\u200b\u200bthe likely habitat of spiders, carefully check your clothes so as not to bring a poisonous guest into the house in the folds of fabric;
• if you meet a spider on your way, then in no case do not touch it and its cocoons.

Not many dare to keep such an exotic and dangerous animal in their home, but the popularity of poisonous spiders, including karakurts, as pets is steadily growing. What conditions are necessary for this arthropod?

Life cycle features

Depending on environmental conditions, the life span of a spider varies from 1 year to 3 years. Males live somewhat less than females. Karakurt live in complete solitude, the only exception is the mating season. In winter, spiders hibernate, and in late spring they begin to mate. During the life of karakurts change the skin from 7 to 9 times. After the last molt, the males mate, and even if the spider was lucky enough to survive, he soon dies of starvation anyway - after marriage, the male loses interest in food. Karakurts can reproduce extremely numerous offspring - at one time, a female spider can lay from 5 to 15 large cocoons with eggs, 100-900 pieces each. The size of cocoons can reach one and a half centimeters. Karakurt females are distinguished by their extremely careful and caring attitude towards offspring, they carefully guard cocoons with babies.

On average, it takes 20 days for eggs to mature, after hatching, spiderlings do not move for several more days - they are completely defenseless, they cannot weave a web, and therefore get food. A week after birth, the first molt occurs.

Soon, the spiderlings get out of the cocoons and begin an independent life. Under natural conditions, a very small percentage of spiders survive from masonry. At home, you can resort to "seating" the young in separate dwellings - in this case, it will be possible to save almost all the offspring. For transplantation, you can use small glass bottles, vials, small plastic containers.

The peak of the attack of karakurt falls on the middle of summer - just at this moment young spiders ripen, moreover, warm weather at the height of the season contributes to the high activity of spiders.

What to feed karakurt?

The diet of karakurt is quite diverse: it can be flies and cockroaches, crickets, locusts, small beetles, goose, midges and mosquitoes, in general, karakurt is not averse to eating all small insects. Since the activity of the spider stops in winter and it hibernates, the arthropod does not need food, but at this time it needs to provide a slightly higher temperature of the terrarium. Under natural conditions, the spider receives food as follows: it is located on the edge of the web, holding a pair of paws on signal threads that go to the farthest ends of the net.

As soon as the victim falls into the trap, the spider receives a signal, gets close to the insect and envelops it with nets that instantly stick together to form a strong cocoon. The victim can no longer move in the cocoon. Then the karakurt makes a bite, the active substances of which turn the victim into a kind of liquid "broth". On average, eating an insect can take more than a day.

Important! From time to time, spiders refuse to eat, this can happen during the molting period. In this case, it is necessary to provide the pet with water. A small plastic container is perfect as a drinker.

It is interesting that karakurt is able to go without food for a very long time, in some cases they may not eat for 6-12 months. However, if you keep a spider in a home terrarium, there is no need to check how long the arthropod will last without food. You need to feed an adult 1 time in 7-10 days, young spiders need to be given food more often - 1 time in 3 days. If you feed young animals, give them slightly “pressed down”, not very active insects, as a young, immature spider may not be able to cope with it.

Terrarium Care

Perhaps spiders are the most undemanding pets to care for. To keep a karakurt, you need to equip it with a terrarium. For this, an ordinary aquarium is suitable, at the bottom of which you need to place sand or small pebbles, as well as leaves, stems, dry branches and moss. To maintain a warm temperature, you can heat the spider's home with a special lamp. Place a container of water in the corner. The terrarium does not require frequent cleaning - it is enough to change the sand once a year. This is best done in the spring, after the winter sleep of the arthropod. Also, be sure to take care of the cover on the terrarium, so that one day you will not find an escaped spider in the house. However, the lid must be with small holes so that air enters the terrarium.

• The male black widow is much smaller than the female. It is not dangerous to humans because it produces only a small amount of poison. The claws on the male's chelicerae are too small to pierce human skin.
• Karakurts have been successfully bred at the London Zoo, where males have mated with females many times and have survived.
• There is an opinion that the black widow after mating necessarily eats the male, but this does not always happen. The appearance of such an assumption is due to the fact that after several matings the male is so weakened that he is often near death. At this time, he cannot escape from the female, and the female eats him.
• In Europe, there is a karakurt, called by the Italians mal-mignatta. The Italian name has been carried over into several other languages. The bite of a karakurt is not as dangerous and painful as the bites of tropical spider species, but the effects are felt for up to 3 weeks.

The black widow is a mysterious spider known for its interesting coloration and cannibalism. In North America, it is considered one of the most poisonous. However, its bite is very rarely fatal.

The black widow got its name because the female, mistaking the male for food, kills, and then eats him. This explains the short life of the latter.

Black widow spider habitat

A separate species of black widow lives in different territories. For example, 8 species are common in Eurasia, 13 in North and South America, and 3 in Australia and Oceania.

In Russia, you can also meet the species of this spider, it is known as white karakurt. The main feature of the spider is round belly yellow or white. At the same time, a bright spot is not typical for this species. Despite the fact that the poison of the karakurt is not as toxic as that of other species, it can still be deadly to children, the sick and the elderly.

Due to global warming, many species have migrated to other habitats. So, more and more often one hears about the appearance of a spider in the Caucasus and the Southern Urals, in Taganrog and the Crimea, in the Rostov region.

Main characteristics

Black widow spider genus has 31 species. Among the species there are especially dangerous representatives for humans and not very.

Appearance

The appearance of a spider largely depends on the species. At the same time, there are features that are characteristic of all representatives:

Lifestyle

Black widows lead a secluded and distant lifestyle. They prefer to live in dark and quiet places, spiders are active at night. An insect spins a web 30-50 cm from the surface of the earth. Outwardly, the web looks asymmetrical, but it is highly durable. The web is needed not only for catching prey, but also for storing female eggs.

Usually spiders weave their web in dry and dark shelters. You can meet an insect not only in open areas, but also in a barn, toilets, garages, in abandoned animal burrows, in stumps. With the advent of cold weather, the black widow spider often moves into the living quarters.

life in nature

Black widows are solitary spiders, except during the mating season. In May, mating occurs. It happens that after mating, the female kills the male and then lays eggs.

Life cycle

The life of a black widow can be divided into three periods:

The life expectancy of a black widow is a year, but some females live up to 3 years. Males are mostly 1–2 months old. As pets, they live much longer.

Nutrition

Like almost all spiders, the black widow feeds on other insects and spiders, which it traps on its webs. The female hangs upside down and waits for the prey. So, she shows her bright body signs, which are recognized to scare away predators. The prey does not pay attention to these markings.

Spider eats midges, mosquitoes, flies, caterpillars and beetles. After the victim has got into the web, the female uses her legs-combs, wrapping the prey in the web. Then it pierces with fangs and injects special enzymes into it, which prepare the prey for consumption.

The black widow spider can live without food for a long time. There are cases when she survived in the absence of food for a year.

black widow and man

The meeting of a black widow and a person can be dangerous for the latter. After all, these spiders were considered the most poisonous on earth for a long time, until they were replaced by the Brazilian soldier spider. Black widow venom is 15 times as toxic as rattlesnake venom. The bite is almost imperceptible on the skin, but the poisons quickly penetrate into the human blood. It is noticed that these insects do not attack first. They can go on the attack if they feel danger to themselves or when they disturb their web.

Bite symptoms

The bite of a spider is a little painful, it feels like a light prick with a thin needle. Symptoms of a bite are:

• redness of the skin at the site of the bite;
• development of edema at the site of the bite;
• after 30 minutes, muscle spasm appears, which is accompanied by pain;
• after another 30 minutes, the abdominal muscles involuntarily tighten, the pain becomes more intense and stronger.

The consequences of a bite

Additional symptoms and possible consequences of a bite:

• increased blood pressure and salivation;
• intense sweating;
• nausea, vomiting;
• bouts of shortness of breath;
• cardiac arrhythmia, tachycardia;
• body weakness, anxiety;
• muscle twitching, headache;
• possible urinary incontinence;
• numbness or tingling of the skin;
• allergic reaction.

After a bite, antivenom should be administered as soon as possible. 3 hours after the bite and failure to take action, the condition may worsen, sometimes even fatal.

Black Widow Prevention

There are some measures that you can take to protect yourself and your home from a black widow:

Despite such a terrible name, the black widow is not an aggressive insect, but rather a shy one. It very rarely bites a human. We are a greater danger to her than the black widow is to us!

View: Spider Black Widow (Latrodectus)
Family: Web spiders
Squad: Spiders
Class: arachnids
Type: arthropods
Subtype: Cheliceric
The size: approximately 38 mm long (feet 12 mm), 6.4 mm in diameter
The weight: 1 gram
Lifespan: 1 - 3 years

The Black Widow got its name because the female often kills and eats the male, which explains his short lifespan. Scientists suggest that this is how females get a ready source of protein that will be useful for offspring. However, this is mostly seen in laboratory settings where the male is unable to escape.

Black Widow has earned a bad reputation unfairly. She only eats her husband when she takes him for food! Despite the fierce-sounding name, these are non-aggressive creatures, even shy ones. They rarely bite people. We are a much greater threat to them than they are to us. They have a completely romantic ritual: the male dances an amazing mating dance so that the female understands that he is not food.

Habitat

This type of spider is distributed throughout the world. They live in regions with a temperate climate, incl. in the US, Southern Europe, Asia, Australia, Africa and much of South America. Can be found in dark, dry hiding places, dimly lit areas such as sheds, garages, basements, closets, hollow tree stumps, rodent burrows, dense vineyard vegetation. They tend to take shelter in warm dwellings in winter.

Although the black widow spider was not previously known in Russia, in recent years they have been found in the Southern Urals and in the Rostov region. Migration is explained by an increase in air temperature.

Characteristic

Like all spiders, the black widow has 8 legs. Male and female individuals are different. Females are twice as large, with shiny black organs and a red hourglass-shaped marking on the underside of their round abdomen. The marking may also be orange-yellow. Males are paler, with red or pink dorsal patches. Females are about 40 mm long with outstretched legs, their black, spherical bellies are about 9-13 mm.

• The eggs are placed in greyish, silky balls 12 to 15 mm in diameter. Clutches contain 200 to 900 eggs and are webbed.
• Spiderlings are completely white at first. Then they become similar to adult spiders, although smaller in size. Photos of black widow spiders are easy to find in the literature, on the Internet.

• The black widow spider, the photo speaks of their danger, still have enemies. Wasps can sting and paralyze them, and it is also a favorite food for praying mantises. Some birds eat them, but may end up getting stomach upset from the poison. The bright red belly markings warn would-be predators that the spider is a nasty food.
• Black widows are lonely in nature. They communicate only during mating. They can sometimes be seen hanging upside down in a net, identified by the hourglass on their abdomen.
• The black widow contributes to the balance of the ecosystem by consuming insects: mosquitoes and flies. It also controls crop pests by feeding on pests that destroy plants: locusts, grasshoppers, beetles and caterpillars.

Interesting! There are 31 species of Black Widow, including: Latrodectus hersperus (western black widow), Latrodectus mactans (southern black widow), and Latrodectus variolus (northern black widow). There are also red widows and brown widows.

Black widow bite

The black widow spider, whose bite is dangerous, and the poison is 15 times stronger than that of a rattlesnake, fortunately rarely attacks people. Only when a person violates his peace. Only the bites of females can be considered a threat to human health. And, contrary to popular belief, most victims do not suffer serious harm. Bites from this spider rarely result in death. Risk group - children, the elderly, the sick.

After a pinprick bite, the pain spreads throughout the body within a few minutes. The effects of a bite from a member of this genus vary by species, but symptoms may include nausea, profuse sweating, severe abdominal and back pain, muscle pain, hypertension, and difficulty breathing. The pain lasts for 8-12 hours, and the symptoms are felt for several days. It is advisable to use an antidote. Animals are more likely to be bitten by a male.

Nutrition

Like many spiders, the black widow eats other arachnids and insects that get caught in its webs. The female hangs upside down and waits for her prey. This posture displays bright markings that are a warning to would-be predators that it is toxic. The markings, however, do not scare the prey.

The spider eats flies, mosquitoes, midges, beetles and caterpillars. Once the prey is caught in the net, the black widow uses her combed legs to wrap the prey in silk. It then pierces its prey with fangs and injects digestive enzymes that liquefy the corpse. And sucks out liquid.

Interesting! Like most spiders, the black widow is able to live for a long time without food. Specimens are known that have survived for almost a year in the absence of prey.

Life cycle

Eggs

A grayish silk ball of eggs with a funnel-shaped exit is attached to the web. Each female builds 5 to 15 of these balls, 12-15 mm in diameter, each containing 200 to 900 eggs. These clutches are fiercely guarded by the mother until spiders emerge from them.

Spiders (babies)

Young spiders leave the ball after 10-30 days. Only a handful of them will survive, as black widows are cannibals in the early stages of their lives. They consume other spiders from their brood for food.

Surviving spiderlings undergo molting. At first they are white, then orange, and only after a couple of months they resemble adult male black widows. Surviving individuals leave the network. It will take 2-3 months for them to mature, begin to weave their linens and get food.

Interesting! Although the life expectancy of black widow spiders is one year, some female specimens live up to three years. Males are usually only 1-2 months old. These spiders live longer in captivity.

Some originals have all sorts of exotics at home and even try to breed them. Spiders were also among the favorites. In principle, it is not difficult to keep and feed them, there is a lot of information on the Internet, but getting offspring is already a problem.

As for the black widow, one of the most dangerous spiders in the world, experts categorically do not recommend keeping it at home and non-professional breeding.

Chasing the exotic, you forget about the elementary instinct of self-preservation. The result can be deplorable, because despite the shyness, 5% of the attacks of such a pet end fatally.

Signs of presence

If suddenly at home or in the country you find the web of a black widow or the spider itself, be careful. Indoors, their webs can be vacuumed out. In fields, orchards, and vegetable gardens where these spiders have become a problem, gloves should be worn as a precaution against bites. Spiders can be killed with a pesticide spray.

Black widows produce dirty dense webs. Her canvases are usually found near ground level and under protected ledges, such as under furniture or a wooden porch on stilts. A red hourglass marking will also indicate the presence of this species.

Origin of the species and description

The black widow genus was classified by Charles Atanas Walkenaer in 1805. Arachnologist Herbert Walter Levi revised the genus in 1959, studying the female reproductive organs and noting their similarities between the described species. He concluded that the color variations were variable across the world and were not sufficient to warrant species status, and reclassified the red and several other species as a subspecies of the black widow spider.

Video: Black widow spider

Levy also noted that the study of the genus had been extremely controversial until then, since in 1902 F. Pickard-Cambridge and Friedrich Dahl revised the genus, each criticizing the other. Cambridge questioned Dahlem's division of the species. He considered the deviations that his opponent drew attention to as minor anatomical details.

It is interesting! In the 1600s, the people of southern Europe danced and raved after being bitten by a species of Black Widow. Movement is said to relieve painful symptoms. Their rhythmic movements were later named the tarantella dance, after the Italian region of Taranto.

Many people don't like spiders. Some believe that they bring bad luck; others, on the contrary, believe that they bring good luck. Black widows have been helpful in controlling pests such as fire ants and termites. In the past, doctors often misdiagnosed after being bitten by a spider. Mistaking the severe condition of the chest and abdomen for symptoms of a perforated appendix.

Appearance and features

The black widow (Latrodectus) is a widespread genus of spiders, a member of the family Theridiidae. The name Latrodectus is believed to mean "secret bite" in Greek. The genus contains 31 species, including the black widows of North America (L. hesperus, L. mactans and L. variolus), the black widow of Europe (L. tredecimguttatus), the Australian red and black widow (L. hasseltii), and the button spiders of South Africa. The species vary greatly in size.

Female widow spiders are usually dark brown or shiny black. Adults have red or orange hourglasses on the ventral surface (underside) of the abdomen. Some species have only a couple of red spots or no markings at all.

Male black widow spiders often have various red, yellow, or white markings on the dorsal surface (upper side) of the abdomen. The females of several species are pale brown and some do not have bright spots. They are larger than males. Spider bodies are 3 to 10 mm in size. Some females may be 13 mm long.

The paws of the widow spider are quite long, relative to the body, and resemble a "comb" with a number of curved, elastic bristles on the hind limbs. Throwing a web on prey is done with a back crest.

On a note! These small spiders have an unusually strong venom containing the neurotoxin latrotoxin, which causes a state of latrodectism.

Female widow spiders have unusually large venom glands and their bite can be especially harmful to large vertebrates, including humans. Despite their fame, Latrodectus bites are rarely fatal or even cause serious complications.

Where does the black widow spider live?

The species can be found on all continents of the world except Antarctica. In North America, black widows are commonly known as southern (Latrodectus mactans), western (Latrodectus hesperus) and northern (Latrodectus variolus). They can be found in all four deserts of the American Southwest, as well as parts of southern Canada, especially in the Okanagan Valley of British Columbia. In addition, on the American continent there are "gray" or "brown widow spiders" (ometricus) and "red widow spiders" (bishopi).

The area of ​​residence is distributed as follows:

• American continent - 13 varieties;
• Eurasia - 8;
• Africa - 8;
• Australia / Oceania - 3 species;
• One species (geometricus) - lives everywhere except Eurasia;
• The most common species found in East Asia and Australia is commonly referred to as the redback (Latrodectus hasselti). Hundreds of Australians are bitten each year by the red spider, a relative of the black widow. It is found in all parts of Australia except for the hottest deserts and coldest mountains.

Interesting fact! Black widows prefer to nest near the ground in dark and undisturbed areas, usually in small holes created by animals, around building openings, or wood piles on the underside of ledges, rocks, plants, and debris. Only cold weather or drought can drive these spiders into buildings.

The brown widow spider (Latrodectus geometryus) is not as dangerous as the black spiders. When bitten, it releases less venom. However, it is a venomous creature and should be handled with care. Found throughout the tropical regions of the world, it has been introduced to southern Texas, central and southern Florida, and is now also found in southern California.

What does a black widow spider eat?

Like most arachnids, the black widow preys on insects. Sometimes she eats mice, lizards and snakes caught in the net, but very rarely. In the deserts, black widows live on a diet of scorpions. It is known that its web is the strongest compared to other types of spiders. Widows do not weave pretty nets, instead they create an elastic weave of thick threads, rough and sticky.

Curious fact! The tensile strength of Black Widow's web has been found to be comparable to that of steel wire of the same thickness. However, since the density of steel is about six times that of the web, the resulting web is stronger than steel wire of the same weight.

To catch prey, black widows create a "tangle" of three levels:

• Support threads on top;
• Clew weaves of threads in the middle;
• Attached to the ground are vertical strings of traps at the bottom with sticky drops.

The spider often hangs upside down near the center of its web and waits for insects to make a mistake and get caught in the web. Then, before the victim can escape, the widow rushes towards her to poison her by injecting poison and wrap her in silk. Her mouth pulses with digestive juices over the prey, which gradually liquefies. The black widow then makes small punctures in the victim's body and sucks on the supstance, allowing it to be sucked back into the mouth.

The prey caught in the net includes various small insects:

• cockroaches;
• beetles;
• flies;
• mosquitoes;
• grasshoppers;
• caterpillars;
• moths;
• other spiders.

Like all spiders, black widows have very poor eyesight and depend on the vibrations in the web's web to find their prey or alert them to danger.

Features of character and lifestyle

The black widow spider is nocturnal. She hides in dark and untouched places, in small recesses created by animals, under fallen branches, piles of trees and rocks. Sometimes they live in rodent burrows and hollow tree stumps. Other habitats include garages, outbuildings, sheds. Nests inside dwellings are found in dark, untouched places such as tables, furniture, basements.

Sexual cannibalism in the female actually increases the chances of offspring surviving. However, females of some species rarely display this behaviour. Most of the documented evidence of sexual cannibalism is in laboratory cages where males cannot escape.

It is interesting! Male black widow spiders choose their mates by determining whether the female is full at the moment in order to avoid being eaten. They can tell if a spider has eaten by looking at the sensitive chemicals in the web.

The widow is not aggressive, but may bite when disturbed. If she is trapped, she is unlikely to bite, preferring to pretend to be dead or hide. Bites are possible when the spider is cornered and unable to escape. Injury to humans is due to defensive bites received when the female is inadvertently pinched or pinched.

Need to know! Black widow venom is poisonous. When the fangs hit the skin, they stay there for a few seconds. The venom glands contract to deliver the venom through ducts in the fangs.

The syndrome resulting from the bite is known as "latrodectism". Painful symptoms are felt all over the body. Black widow venom has been called "neurotoxic" because it acts on the nerves. When the nerve endings do not work: the muscles cease to obey, the body becomes rigid, paralysis and convulsions intensify. Sometimes the respiratory muscles stop working, causing suffocation.

Social structure and reproduction

Typically, black widows mate in spring and summer. The female produces an egg mass containing about 200+ eggs. She covers the eggs with cobwebs, then forms a bag out of this, which should protect the eggs from external influences. The bag is hung on a web to keep it away from predators.

It takes about two weeks for the eggs to hatch. Very few young spiders survive because they eat each other as soon as they are born. Spiderlings molt several times before reaching maturity. Diet and temperature are factors that affect the development of offspring.

Remember! Females take 2 to 4 months to mature and have a lifespan of about 1.1/2 years. Males mature in 2-4 months and live for about 4 months. They lose their outer covering (exoskeleton) as they grow.

Sexual contacts between mating spiders are longer if the male allows himself to be cannibalized. By sacrificing his life, he can fill his partner with more sperm. The female holds this sperm in two storage organs and can control when she uses these stored cells to fertilize her eggs.

If she has sexual contact again, the sperm of the second male may displace the sperm of the first. But females that eat their first mate are more likely to reject the next one.

Natural enemies of the black widow spider

These spiders, although a little scary, also have enemies. Several types of wasps can sting and paralyze a spider before being eaten. The black widow is also the mantis' favorite food. Some birds may eat these spiders but end up with an upset stomach.

Bright red or orange markings in the abdomen warn predators that this is a disgusting food. Most vertebrates that hunt visually pick up this red-black signal and avoid using it.

Among spiders, brown widows usually replace blacks fairly quickly in their habitats, although it is not known for sure if this is a sign of predation, perhaps they simply drive them away in some other way. Some varieties of cellar spiders also enthusiastically feed on black widows.

Other arthropods can eat black widows, but must be able to grab the spider before it bites them, which they rarely do.

This is a very fast spider, it is able to detect small vibrations produced by a predator in advance. If he is in danger, he descends to the ground along the web and hides in a safe place. The spider often pretends to be dead to deceive a potential adversary.

The blue mud wasp (Chalybion californicum) of the western United States is the main predator of the black widow. Alligator lizards can also sometimes "eat" such extravagant food.

Population and species status

The population of the black widow at the moment is not threatened by anything, and even vice versa. New research shows that over time, the black widow's habitats are expanding northward and in other directions beyond its usual habitat.

Climatic factors are responsible for changing the habitat of this dangerous insect. For black widows, the most important predictor of their distribution range is the average temperature of the warmest three months of the year. These updated sightings mean health officials in regions not used to seeing a black widow need to be prepared for one.

The bite of a black widow can be distinguished by two punctures in the skin. The venom causes pain in the area of ​​the bite, which then spreads to the chest, abdomen, and entire body. The Centers for Disease Control and Prevention says black widow bites are not usually life-threatening for adults, but they can cause severe pain and painful muscle contractions. People bitten by a black widow are advised to seek professional medical attention.

To combat spiders, insecticides are applied in their habitats when an infestation is detected. Repeat the treatment is carried out at the interval indicated on the label. To further discourage spider entry into your home, you can use an insecticide barrier spray around the base of the home and possible entry points such as door sills, windows, and foundation vents.

According to the researchers, it is very likely that black widow spider also available further north. The next step is to conduct further sampling efforts in the habitats associated with these spiders.