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Spiders that sting: Identifying and Treating Spider Bites

Identifying and Treating Spider Bites

By Markham HeidMedically Reviewed by Mohiba Tareen, MD


Medically Reviewed

Spider bites can look very different from person to person, and much also depends on the type of spider.Leonardo Briganti/Alamy

You spot an angry-looking red welt on your leg, and it seems too big to be a mosquito bite. Must be a spider bite, right?

Not so fast. “People wake up in the morning and find a red mark, and immediately call it a spider bite,” says Rick Vetter, a retired staff research associate and entomologist at the University of California, Riverside. But most of the skin issues people pin on spiders are actually other types of bug bites or skin issues, he says.

Other researchers back Vetter up on this. “Spider bites are really rare,” says Jonathan Day, PhD, a professor emeritus of medical entomology at the University of Florida. He explains that most “spider bites” are more likely mosquito bites that were scratched and became infected. “Spider bite is a catchall grouping whenever there’s a severe skin infection; they’re all lumped in as spider bites,” he says.

So the first thing every spider expert in America would like people to know about spider bites is that they’re uncommon and often misdiagnosed. That said, some spiders do bite people, and the result can be ugly.

RELATED: Everything You Need to Know About Bug Bites and Related Diseases

Identifying a Spider Bite: What Does One Look Like?

A lot of things. “There’s no one true spider bite,” Vetter says.

Spider Bites Can Look Very Different

Different types of spider bites may provoke different reactions in different people, he says. Even if you’re talking about just one type of spider — say, the brown recluse — its bite could cause a range of reactions, “everything from a little pimple-like bump to a rotting-flesh lesion,” he says.

At the same time, Vetter allows that different types of spider bites do produce distinct reactions. “I’ve had patients contact me saying, ‘This mark on my leg was either from a widow or a recluse,’ but that’s like saying you either got stabbed or trampled to death,” he says. His point: Black widow and brown recluse bites are so different that they could never be mistaken for one another.

But when it comes to common household spiders, hobo spiders, and other domestic varieties, a spider’s bite has some predictable characteristics.

How to Identify Which Spider Bit You

Broadly speaking, a spider’s bite tends to resemble a bee sting: a sharp prick of pain is followed by a red, inflamed skin lump that may hurt or itch but that goes away after a few days. (1) But when it comes to venomous spider bites, there are characteristic signs and symptoms.

Brown recluse bites sting, and they can resemble anything from small blisters to large, rotting-flesh sores, Vetter says. “Its bite causes the collapse of the capillary bed” — also known as skin necrosis (2) — “so people who are obese and have poor support of the capillary cells may have a more massive reaction,” he explains. Along with a wide variety of skin symptoms, brown recluse bites can cause chills, fever, nausea, and other flu-like symptoms common to infections. (3) The brown recluse’s bite is poisonous and can result in coma, kidney failure, or even death.

Because of the severe reaction a brown recluse bite can trigger, these spiders are likely blamed for more harm than they actually cause. The reality is that the brown recluse spider is limited in its geographic range: It’s found in the central and southern United States. (4) The Centers for Disease Control and Prevention (CDC) notes that while venomous spiders are dangerous, they aren’t usually aggressive. (2)

Black widow bites can in some cases cause skin lesions, ranging from small red marks to angry, red, streaky skin patches that are inflamed or contain pus. “But most of the reaction will be on the inside,” Vetter says.

Black widow bites contain potentially deadly amounts of venom and tend to be painful right away. Although that pain starts around the bite site, within an hour, it often spreads to the chest or abdomen, depending on whether the bite occurred on the victim’s upper or lower body. Other symptoms can include everything from headaches, muscle weakness, and difficulty breathing, to seizures, numbness, and painful muscle cramps. (5)

Hobo spiders, wolf spiders, house spiders, and the bites of other domestic types do not contain venoms that are of medical importance to humans, Vetter says. They can bite, he adds. But the result is likely to be similar to a bee sting — meaning a sharp pain, followed by a swollen, red, painful lump at the bite site.

Spider Bites Usually Heal on Their Own. Here’s When to Seek Medical Attention

If you think you were bitten by a black widow or brown recluse spider — either because you actually felt and saw the spider, or you’re experiencing the types of skin or systemic symptoms consistent with their bites — head to the emergency room. (6) Vetter says that recluse bites do usually heal on their own and don’t cause scarring wounds. But it’s better to play it safe.

If your spider bite isn’t causing any internal symptoms, or you’re sure it wasn’t a black widow or brown recluse that bit you, follow these steps:

  1. Clean the bite with soap and water.
  2. Swab the bite with alcohol to prevent infection, Dr. Day recommends.
  3. Apply ice or a cold compress to keep the swelling down.

If pain or itching develops at the bite site, it’s fine to take OTC pain meds or antihistamines for relief. But if pain spreads beyond the site of the bite, or if the swelling, inflammation, or redness are getting worse even a day or two after the bite occurred, get medical attention. You may have a secondary infection — something caused by bacteria getting into the bite — or you may have been bitten by a widow or recluse, Day says.

Why Do Spiders Bite People?

Unlike many other biting bugs, spiders are neither bloodsuckers nor flesh eaters. Vetter says they bite people for one reason only: self-defense.

“Biting is a last-ditch defensive response if a spider is being squashed,” he says. This can happen when someone rolls over in bed on top of a spider — or sits down on one, he says. “I’ve transferred spiders hundreds of times, and they’ll be running all over my arm and have no interest in biting,” he adds.

So while spider bites do occur, they’re far less common than most people assume.

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Editorial Sources and Fact-Checking

  1. Spider Bites. MedlinePlus. August 9, 2014.
  2. Types of Venomous Spiders. Centers for Disease Control and Prevention. May 31, 2018.
  3. Brown Recluse Spider. MedlinePlus. July 20, 2021.
  4. Brown Recluse Spider. Entomology at the University of Kentucky. July 12, 2018.
  5. Black Widow Spider. MedlinePlus. July 20, 2021.
  6. Spider Bites: First Aid. Mayo Clinic. June 11, 2021.

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9 of the World’s Deadliest Spiders


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More than 43,000 different species of spiders are found in the world. Of these, only a small number are said to be dangerous, and less than 30 (less than one-tenth of one percent) have been responsible for human deaths. Why are so few spiders harmful to humans? Much of the reason may result from the size differences between people and spiders. Spider venom is designed to work on smaller animals, but the venom of some species can produce skin lesions in people or produce allergic reactions that result in fatalities. It is important to understand, however, that “death by spider bite” is very rare since clinics, poison control centers, and hospitals often have various species-specific antivenin (the antitoxin) on hand to treat the bite.

  • Brown Recluse Spider (

    Loxosceles reclusa)

    brown recluse spiderJohn H. Gerard/Encyclopædia Britannica, Inc.

    The brown recluse spider is one of the most dangerous spiders in the United States. Its venom destroys the walls of blood vessels near the site of the bite, sometimes causing a large skin ulcer. Research in 2013 revealed that a protein in the spider’s venom targets phospholipid molecules, which make up a good portion of cell membranes, and transforms these molecules into simpler lipids. The wound that is produced may require several months to heal, or it may become infected, which could lead to the death of the victim. Deaths from brown recluse spider bites are rare.
    Most brown recluse spiders, which are also called violin spiders, live in the western and southern United States. Most are about 7 mm (0.25 inch) and have a leg span of about 2.5 cm (1 inch). On the front half of its body (the cephalothorax), it has a dark violin-shaped design, the “neck” of which is formed by a conspicuous furrow on the midline of its back. The brown recluse has extended its range into parts of the northern United States, making its home in caves, rodent burrows, and other protected environments. Brown recluse spiders also set up shop in the undisturbed spaces of buildings, such as attics, storage areas, and wall or ceiling voids.

  • Brazilian Wandering Spiders (

    Phoneutria fera and P. nigriventer)

    These species are sometimes also referred to as banana spiders because they are frequently found on banana leaves. They have an aggressive defense posture, in which they raise their front legs straight up into the air. Phoneutria are poisonous to humans, and they are considered to be the deadliest of all the world’s spiders. Their venom is toxic to the nervous system, causing symptoms such as salivation, irregular heartbeat, and prolonged, painful erections (priapism) in men. Scientists are investigating the venom of P. nigriventer as a possible treatment for erectile dysfunction.
    In late 2013, a family in London, England, had to move out of their home so it could be fumigated, because it became infested with tiny Brazilian wandering spiders. An egg sac deposited in a banana bunch was shipped to the family’s local grocery store. (The egg sac went undetected by the supermarket chain and the importing company it works with.) After the bananas were purchased, the egg sac broke open, releasing its potentially deadly contents.

  • Yellow sac spider (

    Cheiracanthium inclusum)

    Yellow sac spiders are Clubionids, a family of spiders (order Araneida) that range in body length from 3 to 15 mm (about 0.12 to 0.6 inch) and build silken tubes under stones, in leaves, or in grass. Cheiracanthium inclusum, found throughout the United States, as well as in Mexico southward through South America, is venomous to humans and is often found indoors.
    The spider’s venom is a cytotoxin (a substance that destroys a cell or impairs its function) that can produce necrotizing lesions, but such lesions occur rarely in bite victims. Still, redness and swelling at the site of the bite are common reactions. Yellow sac spiders are not docile creatures; a female yellow sac spider, for example may bite when defending her eggs.

  • Wolf spider (family Lycosidae)

    Wolf spiders belong to the family Lycosidae, a large and widespread group that is found throughout the world. They are named for their wolflike habit of chasing and pouncing upon prey. About 125 species occur in North America, whereas there are about 50 in Europe. Numerous species occur north of the Arctic Circle. Most are small to medium-sized. The largest has a body about 2.5 cm (1 inch) long and legs about the same length. Most wolf spiders are dark brown, and their hairy bodies are long and broad, with stout, long legs. They are noted for their running speed and commonly occur in grass or under stones, logs, or leaf litter, though they may invade human dwellings that harbor insects. Most species build silk-lined, tubular nests in the ground. Some conceal the entrance with rubbish, whereas others build a turretlike structure above it. A few species spin webs. Wolf spider eggs are contained in a gray silk sac attached to the female’s spinnerets, or silk-producing organs, so that she appears to be dragging a large ball. After hatching, the young spiders ride on the mother’s back for several days.
    Although the spider is not considered to be aggressive, it will often bite people in self-defense. Wolf spiders are venomous, but their bites are not considered dangerous. (Some bite victims who are allergic to spider bites in general may become nauseous, dizzy, and develop an elevated heart rate, however.). The spider’s large fangs cause physical trauma at the site of the bite. The bite itself has been described as similar to that of a bee sting, and the venom the spider injects may cause itchiness at the site. This painful bite, coupled with their speed and startling appearance, can be unsettling, and some bite victims panic from the experience.

  • Black Widow Spider (

    Latrodectus mactans)

    black widow spider (Latrodectus mactans)Encyclopædia Britannica, Inc./Patrick O’Neill Riley

    The black widow is responsible for more than 2,500 visits to poison control centers every year in the U. S. It is one species that can be found from the United States and parts of Canada through Latin America and the West Indies. The most common member of Latrodectus in North America, it makes its home in a variety of settings, such as woodpiles, burrows, or among plants that serve as supports for its web.
    The female is shiny black and usually has a reddish to yellow hourglass design on the underside of the spherical abdomen. Sometimes two small triangles, instead of a complete hourglass, are present. The body is about 2.5 cm (1 inch) long. The male, seldom seen because it is often killed and eaten by the female after mating (hence the spider’s name), is about one-fourth the size of the female. In addition to the hourglass design, the male often has pairs of red and white stripes on the sides of the abdomen.
    Its bite, which may feel like a pinprick on the skin, often produces severe muscle pain and cramping, nausea, and mild paralysis of the diaphragm, which makes breathing difficult. Most victims recover without serious complications. Although the bite is thought to be fatal to very small children and the elderly, no deaths have been attributed to bites by widow spiders in the United States.

  • Brown Widow Spider (

    Latrodectus geometricus)

    Brown widow spiderEncyclopædia Britannica, Inc./Patrick O’Neill Riley

    The brown widow is thought to have evolved in Africa, but the first specimen described came from South America. It is classified as an invasive species elsewhere around the world. Brown widow populations have appeared in southern California, the Caribbean, the U.S. states of the Gulf Coast, as well as in Japan, South Africa and Madagascar, Australia, and Cyprus. The species makes its home in buildings, inside old tires, and under automobiles, as well as among shrubs and other vegetation.
    The spider has a brownish appearance that ranges from tan to almost black. The abdomens of some specimens have ornate dark-brown, black, white, yellow, or orange markings. Unlike other members of the genus, the hourglass marking on the underside of the brown widow is orange.
    Brown widow venom is considered to be twice as powerful as that of the black widow; however, the species is not aggressive and only injects a tiny amount of venom when it bites. Still, brown widow bites were associated with the deaths of two people in Madagascar in the early 1990s. (These victims were in poor health and were not treated with antivenin.)

  • Red Widow Spider (

    Latrodectus bishopi)

    red widow spiderEncyclopædia Britannica, Inc./Patrick O’Neill Riley

    The third widow spider on this list is the red widow, or red-legged widow. The spider’s appearance is distinguished from other widow spiders by its reddish cephalothorax and legs and its reddish-brown to black colored abdomen. Many red widows have a red mark on the underside of the abdomen, which may be either hourglass-shaped, triangle-shaped, or indistinct. The top of the abdomen is spotted red or orange, with each spot surrounded by a yellow or white outline. The legspan of an adult female is 1.5-2 inches, whereas the male is only about one-third of that size.
    Currently, red widow spiders inhabit palmetto-dominated scrublands in central and southern Florida; however, some experts believe that this range may be expanding. The spider feeds on insects, and it is not considered to be aggressive toward people. However, it has been known to bite when it is protecting its eggs or when it is trapped against a person’s skin by clothes or footwear. The bite of the red widow is similar to that of the black widow, and identical symptoms (pain, cramping, nausea, etc.) typically result. Likewise, death from a red widow bite is rare, since the spider injects such a small amount of venom. Very young children, the elderly, and people with health problems are most vulnerable to red widow spider bites.

  • Redback Spider (

    Latrodectus hasselti)

    Redback spider (Latrodectus hasselti)Encyclopædia Britannica, Inc./Patrick O’Neill Riley

    The redback is another cousin of the black widow L. mactans; however, this species is not as widespread. It is native to Australia, but it has spread to New Zealand, Belgium, and Japan through grape exports. (The spider often builds nests and webs on grape leaves and inside bunches.) The species is widespread throughout Australia, living in all of the continent’s varied environments, except for its hottest deserts and frigid mountaintops. The species is also found in urban areas, frequently making nests in human dwellings. The redback is identified by its prominent red stripe or hourglass-shaped mark on its black-colored back. This mark is more noticeable on female redbacks than on males.
    Redback spiders are not aggressive and are more likely to play dead when disturbed, but a female spider defending her eggs is very likely to bite. Bites also occur when the spider climbs into shoes or clothing and becomes trapped against the victim’s skin when he or she is dressing. Both male and female redbacks are venomous, but most envenomations primarily result from female bites. Only 10-20% of all victims bitten are envenomed. The venom is a mix neurotoxins called alpha-latrotoxins, which produces pain, sweating, rapid heartbeats, and swollen lymph nodes. The spider can moderate the amount of venom it injects, and the severity of these symptoms often depend on how much venom is delivered. More than 250 redback bites are treated each year in Australia, many with antivenin. Researchers and physicians are split on the effectiveness of redback antivenin, with some studies indicating that it was not effective in treating symptoms or relieving pain. Nevertheless, the last human death attributed to redback envenomation occurred in 1956.

  • Funnel-web Spiders (family Dipluridae)

    Sydney funnel-web spider (Atrax robustus) Encyclopædia Britannica, Inc./Patrick O’Neill Riley

    This family of spiders in the order Araneida are named for their funnel-shaped webs, which open wide at the mouth of the tube. The spider sits in the narrow funnel waiting for prey to contact the web. When this happens, the spider rushes out and captures the insect prey at the funnel’s mouth. The most important genera are Evagrus, Brachythele, and Microhexura in North America, Trechona in South America, and the poisonous members of the Atrax genus in Australia.
    The species Atrax robustus and A. formidabilis are large, brown bulky spiders that are much feared in southern and eastern Australia because of their venomous bites. Several human deaths from the bites of these aggressive spiders have been recorded in the Sydney area since the 1920s. An antidote to the main toxin in their venom has been developed which is effective if administered to victims soon after they have been bitten.

ERR overview: which insects and arachnids are willing to bite and sting the people of Estonia | Ecology

Summer in Estonia is not complete without a can of spray against annoying insects. Mosquitoes, horseflies, ticks and midges are not the only representatives of the local fauna, lying in wait for their prey or even chasing it. The editors of the ERR portal decided to find out which insects and arthropods pose a danger to humans. The topic is commented by the biologist of the Museum of Nature Katerina Pesocki.

Some insects have been familiar to Estonians since early childhood and usually evoke only positive emotions. A prime example of this is the ladybug. The reddish-orange insect of the ladybug family, or coccinellids – the seven-spotted ladybug – immediately catches the eye and is usually perceived as the cutest creature. People often pick it up to take a picture or see how spectacularly the insect will take off from their finger. But there is also an unexpected turn when the ladybug bites.

The seven-spotted ladybug is able to use its mouthparts to bite a person, among other things. Author: Pixabay

Although this small insect is not capable of biting the skin to blood, an unexpected bite can still scare a person. How is it that such a cute insect suddenly bites? The fact is that many representatives of arthropods, especially those with a gnawing type of mouth apparatus, are quite capable of using their weapons, including for self-defense purposes.

Common earwig. Terrible in appearance, but does not bite. Posted by Melani Marfeld / Pixabay

It also happens that not only the jaws, but also various outgrowths on the body can serve as means of self-defense. For example, there are such interesting insects as earwigs. At the end of their elongated body, on the last segment of the abdomen, there are processes called forceps. The insect uses them perfectly, like tongs. They can also be used in self-defense, although often the insect simply frightens by demonstrating its formidable weapon.

Spiders: there are no extremely dangerous spiders in Estonia, but the bite of some can be painful

Defending themselves, not only insects can bite, but also, for example, spiders.

All spiders living in Estonia are predatory “comrades” (lead a predatory lifestyle), and their adaptations are appropriate. Spiders have mouth appendages, chelicerae, and venom ducts that they inject into the victim’s body. The venom of the spiders living in Estonia is not lethal to us, but the bite of large spiders with fairly strong chelicerae can be painful. The bite of some single species can cause redness on the skin, swelling and fever. However, there are no spiders living in Estonia whose venom is extremely dangerous.

In Estonia, there is a yellow-headed piercing spider. Its venom can cause nausea and fever. Author: Fritz Geller-Grimm/Wikipedia

All of the arthropods mentioned use their weapons exclusively for self-defense. Not a single ladybug would think of climbing on a sleeping person to bite him.

Hematophagous: pursue and attack

There are some representatives of arthropods that lead a parasitic lifestyle and are hematophagous, that is, their diet consists of blood. They pursue prey and actively attack.

Some have adapted so effectively to a parasitic way of life that they live with their potential victims: bed bugs and lice with humans, fleas with dogs.

Fleas, bed bugs and louse prefer to coexist with their prey. Author: collage

Other representatives of hematophagous arthropods prefer to live in nature and patiently wait for a meeting with their prey. Among arachnids, these are, of course, ticks.

Ixodid ticks in Estonia

If a person doubts whether a tick is crawling on him, then you can count the limbs: a tick with a flat brownish body has eight limbs. Different types of ticks live in Estonia, of which two species parasitize humans: the taiga tick and the dog tick. The name of the latter does not mean that it is found only in dogs.

The dog tick carries diseases such as Lyme disease, encephalitis, Marseilles fever. Author: Erik Karits / Pixabay

It should be understood that ticks do not fall from trees like pine cones. They wait for their prey on low plants. According to my personal observations, there are more ticks in 2020 than in the past. This was facilitated by a warm winter.

If ixodid ticks are waiting for their prey, sitting in ambush, on some relatively long blade of grass, trying to catch the approach of the desired object with the help of receptors, then some insects have to actively move in search of their prey.

Mosquitoes and their relatives – midges and midges

Everyone knows how piercing the mosquito squeak sounds at night, when the insect flies in the silence of the room above the ear in search of access to blood. There are over 1200 species of mosquitoes in Estonia, but don’t worry – not all of these species feed on blood. There are three families: blood-sucking mosquitoes, midges and midges. They use blood, including human.

The female mosquito needs blood to continue offspring. Author: Pixabay

About 30 species of mosquitoes “drink” human blood. Most of them parasitize humans in the warm season, but there are exceptions, such as the basement mosquito. Such an insect in nature can be found in warm countries. Once in Estonia, this species has adapted to breed in damp basements, and the cold winter does not bother it. Usually, blood-sucking mosquitoes that breed in the nature of our country are active from spring to late autumn. Among blood-sucking mosquitoes, as you know, females “drink” blood, they need it for the development of germ cells and laying eggs.

Mosquitoes’ relatives include midges and midges.

Biting midges are one of the smallest blood-sucking parasites among insects, they are no more than 3 mm in length. These insects begin to fly actively around the time of cherry blossom, but become especially annoying by the beginning of July. It is the females who consume the blood, their bites are painful and cause redness on the skin. There are about 20 species of biting midges in Estonia.

Female midge. Author: Wikipedia

Among the bloodsuckers there are also smaller representatives – midges. The species diversity of midges in our country is also within 20 species. Their saliva causes intense itching.

Deer bloodsuckers, gadflies and blueberry calyptera

In addition to mosquitoes and their relatives, various flies show interest in blood. One family of insects is called the bloodsuckers.

The most famous representative of the bloodsucker in our country is the deer bloodsucker, more often it is called the moose fly. You can meet them in those forests where moose, deer, roe deer and wild boars live. In dry forests without succulent vegetation, and therefore without food for elk and deer, these flies are not found. Most often, a fly crawls over its prey without wings. The fact is that when she lands on her food object, she gets rid of her wings forever.

Deer bloodsuckers are confused with ticks because, once on the body, they shed their wings. Author: Flickr

In addition to deer bloodsuckers and other flies, the well-known gadflies also belong to the short-whiskered suborder. If you tell a child that a horsefly is a large fly, with big eyes and a desire to taste blood, this will not be a lie.

The horsefly has really big eyes to see its prey. Although horseflies are good flyers and can easily fly a couple of kilometers, they still do not fly far from the reservoir. Horse flies are usually active from late May to mid September. The greatest activity is achieved on hot summer days, in cloudy and rainy weather the activity of horseflies decreases. Females feed on blood, males consume plant foods.

Houseflies do not bite

Our harmless housefly has a close relative in the family – the autumn stinger, about 5-7 mm in length. Some people might think that these are house flies “go crazy” by autumn and start biting people, but no. Closer to autumn, it is not at all house flies that attack, but autumn zhigalki. These insects can attack not only in nature, but also indoors. So the housefly bite is a myth.

Autumn Stinger attacks mainly animals, but does not disdain people either. Author: Pavel Krok/Wikipedia

In addition to representatives of the order Diptera, which was discussed earlier, sometimes some representatives of Lepidoptera present surprises. A harmless butterfly is not associated with vampires, and meanwhile, among Lepidoptera there are such species, the diet of which, among other things, includes blood. Although the calyptra cornflower is found in our country, cases of this butterfly attacking a person are very rare, because blood is not the main diet of this insect.

The attack of the calyptra basilis on a person is a rarity. Author: Dumi/Wikipedia

scientist spoke about dangerous species of spiders in the Volgograd region


3 Jul 16:18, 4 photos

These small representatives of the fauna begin to show activity in the region from May, and end in autumn.

The hot climate of the Volgograd region is not only a certain temperature discomfort for its inhabitants. The lack of heavy rains creates a favorable environment for the appearance of poisonous spiders. Many of the arthropod fauna have successfully migrated from neighboring Kazakhstan. The other day, in social networks, Volgograd residents shared messages that they had met a salpuga in nature, which they had never seen in these places before. Karakurts generally become almost an ordinary phenomenon for local residents, but at the same time no less dangerous. So, in May, a resident of the Novoanninsky district “boasted” that he had discovered a poisonous spider in the courtyard of his house. Fortunately, no one was hurt. The poison of the karakurt is painful and deadly, it is 17 times stronger than the poison of a rattlesnake. As they say, evaluate the odds.

Elena Ivantsova, doctor of agricultural sciences, professor, director of the Institute of Natural Sciences of the Volgograd State University, told Gorodskiy Vesti what spider species dangerous to humans live in the Volgograd region.

– Karakurt is the most dangerous species of spiders for humans, living in hot arid conditions of the Volgograd, Astrakhan regions, Kalmykia, Dagestan and the east of the Rostov region, – says the professor. – Directly on the territory of the city of Volgograd, the population of karakurt was noted from the end of 90s, but is not observed every year, but usually during outbreaks of the species.

The body of poisonous spiders is spherical. The female karakurt is much larger than the male, her body with a span of legs in length is approximately 2. 5 cm, male individuals are much smaller – only 6-7 mm. Four pairs of limbs are located on both sides of the body. Two pairs of middle tarsi covered with hairs. The first and last pairs are distinguished by the greatest length. The color of spiders is distinguished by the presence of red or orange spots of various shapes. Sometimes a white border of each spot is added to the pattern on the body.

– The venom of a female spider can be fatal. After a bite, burning pain after 15-20 minutes spreads to neighboring parts of the body and organs, then, after 20-40 minutes, a burning sensation appears throughout the body, chills, weakness, mental arousal develops. The pulse becomes frequent, breathing is difficult, heart sounds are muffled; blood pressure initially rises. Some patients experience salivation and difficulty swallowing. After 2-3 hours, cramps of the lower and upper extremities appear. Later, nausea, vomiting, tension of the rectus abdominis muscles and constipation, puffiness of the face, swelling of the eyelids and heavy sweat, which is combined with chills, appear. The temperature is subfebrile from the norm to 38 ° C, less often normal or high. When bitten by a karakurt, you must immediately seek help from the nearest medical facility or call an ambulance, warns Elena Ivantsova.

In addition to karakurt, two types of tarantulas are considered dangerous for humans: South Russian and huge. Tarantulas are one of the largest spiders in the Volgograd region, reaching sizes up to 3 cm without legs and up to 6 cm with legs. The development cycle of individuals of both species reaches up to four years; in the first year after birth, spiders lead a wandering lifestyle, and in the second year they build burrows where they hide from predators and wait for prey running past.

Despite the reputation, the danger to humans from tarantulas is greatly exaggerated. The tarantula will in any case prefer to run away or warn with a threatening posture before launching the chelicerae.

– The venom of a tarantula is comparable in strength to that of a wasp, however, the amount of this poison is much greater than that of a wasp, that is, the feeling after a spider bite is comparable to the feeling from a bite of two or three wasps. Two punctures will be visible at the bite site, then swelling and redness of the skin appear, accompanied by burning and itching, and a short-term increase in temperature is possible. People who do not suffer from allergies do not need special treatment, Professor Ivantsova comments.

Help will be to wash the wound surface as soon as possible. Clean running water is suitable for washing, which will avoid infection. You can use soapy water. It is advisable to treat the wound with an antiseptic – hydrogen peroxide, chlorhexidine, if such medicines are at hand. In order to relieve swelling, you can use a cold compress from ice or another product that is in the freezer.

However, if symptoms of an allergic reaction are observed, medical attention should be sought immediately. Otherwise, a severe allergic reaction can be fatal.

Southern Russian tarantula is outwardly distinguished by the following features: body color varies from dark sand to dark brown, almost black. There are 6 pairs of lighter spots on the upper side of the abdomen. The whole body is covered with dense hairs. Legs with numerous spines, which are not very noticeable surrounded by hairs. The underside of the body is intensely black. The abdomen is oval, in size the female is slightly larger than the cephalothorax, and the male is slightly smaller. The legs are of medium length (approximately equal to the length of the body) and thick compared to spiders from other families.

Huge Tarantula – this is the name of another dangerous spider – in size, shape and body proportions it is very similar to the South Russian one, but it differs significantly in color. It varies within shades of grey. On the abdomen there is a rather complex leaf-like pattern. The cephalothorax and legs are colored like those of the South Russian tarantula, but the abdomen is very different. In young animals it is orange and there is a black dot in its center. With age, this point increases in size and, by reaching its maximum size, occupies almost the entire abdomen.