The black widow spider The black widow spider (Latrodectus mactans) is a spider notorious for its neurotoxic venom. It is a large widow spider found throughout the world and commonly associated with urban habitats or agricultural areas. Although the common name 'black widow spider' is used to refer specifically to L. mactans it is occasionally also applied to several members of the Latrodectus (widow spider) genus in which there are 31 recognized species including the Australian red-back and brown widow spider. In South Africa, the black widow is also known as the button spider. This well known and misunderstood pest is famous for its mating rituals where the female kills and consumes the male after copulating. The male Black Widow spider is smaller and totally harmless to man. The female is easily identified by the red hourglass shape on the abdomen. Black Widow poison is 15 times more lethal than rattlesnake venom; however, less poison is actually injected in a bite so far fewer people die from spider bites. Black Widows prefer dark, humid places like wood piles, basements, and crawlspaces. Modern pest control methods are very effective in controlling and preventing spider infestations.

Adult female black widow spiders are shiny black with an hourglass shaped marking on the bottom of its abdomen which, although most commonly red, may range in color from white to yellow to various shades of orange and red. They also bear a small, usually red (colors vary) dot near the spinerettes, which is separate from the hourglass. In some varieties, the two halves of the hourglass shape may be separated into two separate dots. A large female black widow spider can grow to 1.5 inches (38 mm), counting legspan. The body is about 0.5 inches (13 mm). Male black widow spiders are half the size of the female or smaller. They have longer legs and a smaller abdomen in relation to their body size. They are also usually dark brown with varying colors of stripes/dots, with no hourglass mark. Adult males can be distinguished from juvenile females by their more-slender body, longer legs and large pedipalps typical of most other male spiders. Juvenile black widow spiders start white, molting to dark brown to black exoskeletons with white, yellow, orange and red stripes and/or dots on their backs.

As with many poisonous creatures, the brightly coloured markings serve as a warning to predators. Eating a blac k widow will normally not kill a small predator (birds, et cetera), but the sickness that follows digestion is enough for the creature to remember that the bright red means not to eat. Because the adult female black widow typically hangs and moves about its web upside down, its hourglass is on its front. However, juvenile widows (female) spend a large quantity of time in search of an optimal environment. Once an optimal location is found, adult female widows often spend their entire lives in one place. However, because juvenile females must first find this optimal location, they bear brightly colored marks upon their backs, so that they may be seen by predators when the widow is travelling upon its legs. Males bear similar marks to the females to serve as warning while they are searching for mates, however, the marks are not as prominent (not as brightly colored, or as large). Males, being less poisonous, are less of a threat to predators, so having similar marks not as prominent helps predators to better judge their prey (some large birds can eat male widows without adverse effect, and so only avoid female widows.

Those who cannot eat any widow without adverse effect eat nothing with the marks.) Female juveniles develop an hourglass before the dorsal markings are shed. The brown recluse spider is a venomous spider, Loxosceles reclusa, of the family Sicariidae (formerly of the family Loxoscelidae). It is usually between 1/4 and 3/4 inch (6.4-19.1mm) but may grow larger. It is brown and usually has markings on the dorsal side of its thorax, with a black line coming from it that looks like a violin with the neck of the violin pointing to the rear of the spider resulting in the nickname "fiddleback spider" or "violin spider". Coloring varies from light tan to brown and the violin marking may not be visible. The brown recluse spider is native to the United States from the southern Midwest south to the Gulf of Mexico. It is native from central Texas to western Georgia. Recluse spiders, which also include Mediterranean recluse spider (Loxosceles ru fescens), build irregular webs that frequently include a shelter consisting of disorderly threads. Unlike most web weavers, they leave these webs at night to hunt.

People get bitten when they unintentionally squeeze them in clothing and bedding. These spiders frequently build their webs in woodpiles and sheds, closets, garages, and other places that are dry and generally undisturbed. As indicated by its name, this spider is not aggressive and usually bites only when pressed against human skin, such as when putting on an article of clothing. Actual brown recluse bites are rare and few. The initial bite frequently cannot be felt. Most bites are minor with no necrosis, but a small number produce severe dermonecrotic lesions or even systemic conditions (viscerocutaneous loxoscelism) with occasional fatalities. (For a comparison of the toxicity of several kinds of spider bites, see the list of spiders having medically significant venom.) It is estimated that 80% of reported brown recluse bites may be misdiagnoses. The misdiagnosis of a wound as a brown recluse bite could delay proper treatment of serious diseases. There is now a test for brown recluse venom that can determine if a wound is a brown recluse bite. The serious bites form a necrotising ulcer that destroys soft tissue and may take months and very rarely years to heal, leaving deep scars.

The damaged tissue will become gangrenous and eventually slough away. Initially there may be no pain from a bite, but over time the wound may grow to as large as 10 inches (25 cm) in extreme cases. Bites may take up to seven hours to cause visible damage; more serious systemic effects may occur before this time, as venom of any kind spreads throughout the body in minutes. Deaths (1.5% of all cases) have been reported for the related South American species L. laeta and L. intermedia. First aid involves the application of an ice pack to control inflammation, the application of aloe vera to soothe and help control the pain, and prompt medical care. If it can be easily captured, the spider should be brought with the patient in a clear, tightly closed container so it may be identified. However, by the time the bite is noticed any spider found nearby is not likely to be the culprit. Species Spotlight: Black Widow Spider Black Widow Spider Like wolves and snakes, the black widow spider is the victim of bad publicity. While they are one of the two potentially dangerous spiders found in Oklahoma, their bad public image is somewhat undeserved.

The truth is that the black widow has not caused any deaths in the United States for several decades. Also, they are a voracious consumer of insects, particularly flies, crickets, and even cockroaches. Black widow is actually the common name given to several long-legged, smooth bodied spiders found in the tropics, southern United States and southern Canada. The female of the species found in Oklahoma, Latrodectus mactans, can be identified by its jet black body with an hourglass-shaped red mark on the underside of the abdomen. When mature, she measures about one and a half inches with her legs extended. Males, which are rarely seen, are only about half as large and usually have four pairs of red dots along the side of the abdomen. Newly hatched black widows are white with black spots on their abdomens and a cream colored hourglass. Later, they become cream and brown-striped, before entering their mature color phase. The black widow requires about four months from egg to maturity with the females going through six to nine molts. Over their one- to two-year life span the females produce several egg sacs, each containing several hundred eggs.

Female black widows guard the sac, which resembles a silken cocoon, until the eggs hatch. During this time she is most likely to bite. Eggs are most frequently encountered between May to October. Black widow spiders are commonly found around homes, garages, barns and other man-made structures. They build tough, irregularly shaped webs with strands running in many directions. The “messy” looking webs are often found in or behind objects in secluded and protected locations. During the summer they are known to set up house near porch lights in order to make an easy meal of the insects that gather there. They hide during the day and often hang upside down in their webs at night. Black widows are the only spiders in the United States with a neurotoxic poison, which means it affects nerves or nervous tissue. The initial bite may feel like a pin prick, and is followed by pain in the vicinity of the bite, muscle aches, severe abdominal pain, vomiting, muscular cramping, sweating, fever and headache. There is usually no swelling of the bite area, but a small lesion may form. Black widow bites are rarely life threatening but can be dangerous for small children or people with chronic health problems.

They also can be dangerous for pets, and are sometimes fatal to small dogs or cats. Contact with black widows can be avoided or minimized by observing these practices: Be cautious when picking up or moving objects, particularly in outbuildings such as shed or garages, or in shady undisturbed areas such as under parked cars or in flower pots. Although they are not commonly found indoors it is always a good idea to shake out and check clothing before putting it on (for brown recluse spiders and scorpions as well). Manage household, yard and garden insects (roaches, crickets etc.). Lack of food will discourage spiders and force them to move elsewhere. Keep outdoor lighting off as much as possible to prevent luring the insects upon which these spiders feed. Remove collections of paper, boxes, rubbish piles in the house, attic, storage areas, etc. As a part of the web of life, black widow spiders are as important as any other species including deer and quail. Where humankind is concerned it is pointless to try to label them as good or bad - they are simply part of the natural world. Whether they are a nuisance or beneficial involves individual perceptions and reactions.

Black Widow Spiders | National Geographic Black Widow Spiders About Black Widow Spiders Black widows are notorious spiders identified by the colored, hourglass-shaped mark on their abdomens. Several species answer to the name, and they are found in temperate regions around the world. Venom This spider's bite is much feared because its venom is reported to be 15 times stronger than a rattlesnake's. In humans, bites produce muscle aches, nausea, and a paralysis of the diaphragm that can make breathing difficult; however, contrary to popular belief, most people who are bitten suffer no serious damage—let alone death. But bites can be fatal—usually to small children, the elderly, or the infirm. Fortunately, fatalities are fairly rare; the spiders are nonaggressive and bite only in self-defense, such as when someone accidentally sits on them. The animals most at risk from the black widow's bite are insects—and male black widow spiders. Females sometimes kill and eat their counterparts after mating in a macabre behavior that gave the insect its name. Black widows are solitary year-round except during this violent mating ritual. Webs and Feeding These spiders spin large webs in which females suspend a cocoon with hundreds of eggs.

Spiderlings disperse soon after they leave their eggs, but the web remains. Black widow spiders also use their webs to ensnare their prey, which consists of flies, mosquitoes, grasshoppers, beetles, and caterpillars. Black widows are comb-footed spiders, which means they have bristles on their hind legs that they use to cover their prey with silk once it has been trapped. To feed, black widows puncture their insect prey with their fangs and administer digestive enzymes to the corpses. By using these enzymes, and their gnashing fangs, the spiders liquefy their prey's bodies and suck up the resulting fluid. © 1996-2017 National Geographic Society. Black Widow spiders - creepy arachnid on a lookout for a kill Navigation The yellow garden spider prefer to roam in its web with its head down. Read More The red back spider prefer to live in its silky nest and it is capable of eating prey its own size Read More The bite from a yellow sac spider is as painful as a bite from a wasp.

Too many house spiders are killed because of this Read More Pictures of the most venomous spiders in the world Read More The golden silk spider wraps its prey (insects) in silk thereby immobilizing it Read More The jumping spider can jump a distance of more than 30 times its own length This habit has been observed in closed containers. It is likely that the observations of large females eating smaller males is more due to the fact that there was no place for the males to escape to. The abdomen of the black widow is black but can have other colors as well. Red Back Jumping S. The black widow, and certainly the mactans, is the largest spider in the family Theridiidae. The female is 8-10 mm long and is identified by two distinctive red hourglass-shaped spots on its abdomen. Latrodectus mactans is found in the USA and the West Indies. Another well-known black widow is the red-back spider. More about the redback is found farther down on this page. Ballooning Young spiders of the genus including young Latrodectus mactans are often dispersed by the wind, a phenomenon known as ballooning.

The small and light spiders climb to the top of a tree, or something else, and allow an air current to carry them. During mating, the male spins a "sperm-web" and deposits semen on it. His palps are then charged with the sperm. He then abandons his habitat and locates a female. The Web of Black Widow Spiders The web of the black widow is an irregular tangled mass and contains a silken retreat where she can hide. The female hangs upside down in her web, where she defends her egg sac. Most bites to humans occur as a defense against attacks on a web. The male is about half the size of the female and has a more oval-shaped abdomen. The male's legs are longer, and it has a spotted appearance. The female black widow is very venomous, but the males aren't. The poison glands of a male aren't functional in its adult stage. Life Cycle Courtship begins when the female black widow spider has been located. During copulation, the male inserts his papal organs into the spermathecal openings of the female and the spermatozoa are released onto the eggs.

Research suggests that once a female Latrodectus mactans has mated, she can store a lifetime supply of sperm to fertilize all the eggs she will ever produce. Habitat Black widow spiders are commonly found outdoors and around human habitation. They have been found in containers, in rubbish, and on or under the seats of outdoor toilets, where it thinks it can stay undisturbed. Other places where this spider is often encountered include beneath logs, bark, sides of rocks, etc.—always close to its web. Black Widow Spider Bites A bite from a black widow can cause severe abdominal muscle spasms. A bite from a black widow can be distinguished from other insect bites by its two puncture marks in the skin. Antivenin is available, so bring the spider to the doctor if possible and let the doctor see her. Red Back Spider It's called the red back spider due to the markings on its abdomen. Its Latin name is Latrodectus hasseltii. The body of a female red back spider is around 0.4 inches and the size of a male is around 1.2 inches. The female produces up to twelve yellow egg sacs, each with approximately 250 eggs in it.

The female red back spider has a black body with white markings on the upper side of its abdomen. It also has the characteristic red hourglass marking on the underside of the abdomen. The abdomen of the red back spider is shaped like a pea. Both males and females have long, slender legs. Are spiders insects? Bites From Red Back Spiders A bite from a red back spider is highly venomous and characterized by intense pain around the bite site. The symptoms from a bite may include sweating, muscular weakness, nausea, and vomiting. It usually starts with a sharp pain; then the bite site becomes hot, and edema develops rapidly. Swelling is limited to an area of up to five cm in radius from the bite site. Five minutes after the bite the pain commences and increases in severity and distribution. About thirty minutes after the bite swelling is experienced in lymph nodes near the area of the bite. Other symptoms have occurred as well. One must be extremely careful handling these animals. Life Cycle The female black widow can store sperm and use it for up to two years after mating to lay eggs. Each egg sac contains more than 200 eggs, and she can lay several egg sacs in one season. The sacs are distributed in her web.

Baby spiders spreads by the wind. The female often eats the male following mating. A link to a video showing the mating can be found in the navigation panel. Females may live for two to three years and males only for three or four months. Wolf Spiders Black Widow (the Red Katipo): New Zealand Black Widow Latrodectus katipo is one of two widow spiders in New Zealand. L.katipo is endemic of New Zealand but unfortunately it is threatened with extinction for a number of reasons. L. katipo is also called the red katipo, while the black katipo actually is an L. atritus. Brown Widow Spiders Appearance The black katipo spider, L. atritus, is characterized by the absence of the characteristic red stripe on its abdomen. L. katipo has the typical red marks. The red black widow has a size of approximately 25 mm. This cobweb spider is also characterized by its untidy web. The size of the male is approximately 1/6 of the female’s size, and the male resembles juvenile female black katipos. katipo's.

Camel Spider Habitat of the Red Katipo The red katipo black widow likes to stay in certain types of grass and sand and/or under logs, stones, or wood. In a larger survey from New Zealand, a lot of specimens were also found in sand-dunes. Bite A bite from the red black widow can be fatal, and deaths have occurred in both New Zealand and Australia. Brown Recluse S. The venom causes pain that develops and spreads within a few minutes. The pain is accompanied by sweating, difficulty in breathing, and vomiting. The degree of effect from a bite is proportional to the amount of poison injected into the bite wound. Tarantula Spiders Miscellaneous The black katipo is a kind of national invertebrate symbol in NZ. It appears on websites, t-shirts, and in e-mails, so it can be considered quite popular. This might be due to its status as a symbol of invertebrate conservation. Common Black Spiders (with Pictures) | eHow Common Black Spiders  Email Save Many animals and insects adopt colors that enable them to thrive where their counterparts fail. Spiders are no exception. Black spiders are found all over the world, in and around the places where people live.

Their dark color allows them to hide in corners and crevices, where they can hunt and live undetected. (marnoitum/iStock/Getty Images) Spiders appear in many different shapes, sizes, and colors, mostly depending on the environments in which they live. Some spiders exhibit bright colors to ward off predators or to camouflage themselves within their habitats. These spiders normally are not the ones that people need to worry about. A few of the more dangerous spiders are very dark in color. These spiders include the North American Black Widow Spider; two Australian species, the Redback Spider and the Mouse Spider; and the many types of tarantulas that are dark-colored. Other common black spiders are the Black House Spider, that inhabits residential areas in Australia; and various types of Jumping Spiders, which are found all over the world. Joerg Mikus/Hemera/Getty Images The Black Widow Spider is one of the most dangerous and most notorious of all the American spiders, though different types of Black Widows are found throughout the world. The female of the species is known for its glossy black exoskeleton, which has a red hourglass-shaped mark on the underside of the abdomen and will feed on the smaller male during mating.

The Black Widow is widespread across the southern portion of the United States and in tropical regions worldwide, and is commonly found in dark places in and around homes. Most build their webs in the corners of garages and sheds and sometimes colonies of them are found under manhole covers. The spider inflicts a painful bite that can cause a variety of symptoms, including vomiting, sweating, fever, and chills; however, the bite is seldom fatal to humans who have a strong immune system and receive immediate care. Mark Kostich/iStock/Getty Images The Redback Spider is the Black Widow's Australian counterpart. The Redback looks strikingly similar to the Black Widow, with the black exoskeleton and the large abdomen, but the red pattern on the abdomen isn't hourglass-shaped. The Redback's and Black Widow's webs are alike in the pattern in which they're constructed and, like the Black Widow, the Redback is also found in dark places near houses. However, the Redback's bite is usually more dangerous than the Black Widow's, and is commonly known for causing sweating at the site of the bite.

The Redback can cause symptoms including vomiting fits, convulsions, and paralysis, and the bite can be lethal to a human if anti-venom medication is not administered. Ian Waldie/Getty Images News/Getty Images The Black House Spider is another common Australian spider whose entire body is black, and which makes its nest in places around houses, most notably in the corners of window and door frames. The spider is small in size, with the female growing up to 17 millimeters and the male reaching 8 millimeters. This spider is not dangerous to humans. The Black House Spider is the natural prey of another Australian species, the White-tail Spider. Marek Lambert/iStock/Getty Images The Mouse Spider is an Australian spider belonging to the Trap-Door family, a type of spider that digs a hole underground and creates a lid at the top of the den to allow them to catch prey. The Mouse Spider can grow to one to three centimeters in diameter; like other species, female Mouse Spiders typically are larger than males. The male Mouse Spider can be identified by its large red fangs–which give it an intimidating appearance–but the female inflicts a more serious bite to humans.

These spiders make their burrows in dry areas and also can be found in rain forests or living in trees. pelooyen/iStock/Getty Images Jumping Spiders are found all over the world and appear in many colors, but many times, the ones that stand out are the larger black ones. Sometimes black Jumping Spiders have colored patterns–spots or stripes of various colors. Jumping Spiders have two large eyes that greatly enhance their long-range vision and they can leap many times their body length. When Jumping Spiders hunt, they will move within striking distance and pounce on their prey, using their strong legs to subdue the prey so that the venom can be injected. While the Jumping Spider's bite isn't poisonous to humans, the bite can be irritable to the skin, especially if the victim is allergic to spider bites. johnandersonphoto/iStock/Getty Images Tarantulas are the largest of all spiders and occur worldwide. They appear in a variety of colors, most notably black, brown, or various hues of red or orange. In the United States, male tarantulas are most commonly seen, especially during mating season when they migrate to search for females. Male tarantulas are often black or dark brown.

Rather than using a web to catch prey, tarantulas will move about to seek insects, small mammals, birds, and reptiles, and they can go for weeks without eating. When frightened, the tarantula may stand on its hind legs and expose its large fangs, or it will turn and flick urticating hairs from its abdomen, which irritate skin and eyes as well as the throat and nasal passages if swallowed or inhaled. Pavel Trankov/iStock/Getty Images Geneva Spider Control: Pointe Pest Control My Account Geneva Spider Control Geneva, Illinois is home to a beautiful Dutch windmill located near the Fox River. Colonel Fabyan, a wealthy man, paid $75,000 to have it dismantled and moved to Geneva. The Fabyan Mill is held together by wooden dowels. All of the machinery inside it are intricately carved hickory gears. It’s a letdown when such beautiful structures are overrun by spiders making their webs. You pay good money for your house. Invest in it and maintain it. You can count on the Geneva spider control experts from Pointe to sweep your spiders and their webs out of your home.

It’s that time of year again when house spiders start to branch out. House spiders will make multiple webs to catch their food. They’ll make these webs in basements, windowsills and on the outer walls of houses. Female house spiders will lay up to four egg sacs. These sacs contain 200 spider eggs. One embarrassing place to find spider webs is on the front door. It’s a sign that you rarely use it and enter the house through your garage. These spiders can quickly populate your house if you don’t keep them in check. Geneva is also home to two poisonous spiders. The black widow is easily identified by the red hourglass shaped mark on its abdomen. A bite from this venomous spider causes pain and muscle spasms that can last several days. The brown recluse is a common spider here. They are identified by their six eyes and violin shaped marks on its head. Brown recluses like to hide in tight, dark spaces. Some are found under towels in bathrooms or linen closets. Briefs: Ahhh! Spiders! – PEM Blog View Larger Image Briefs: Ahhh! Spiders! Happy Halloween everyone.

I thought I’d “celebrate” by posting about some rare but still clinically important spider bites. The two that get the most press in United States are the black widow (Latrodectus mactans) and brown recluse (Loxosceles reclusa). Fortunately, there are only approximately 500 bytes a year in the United States and deaths are very rare. Black Widow Spiders Black widow spiders are found in the temperate and tropical zones of the earth. They normally only bite humans in self defense. Only the female is venomous to humans – It can be identified by its black color and the red hourglass shaped mark on its abdomen The venom causes the of norepinephrine, GABA and acetylcholine via exocytosis of synaptic vesicles. It also leads to degeneration of motor endplates which leads to denervation as well as destabilization of nerve cell membranes which causes a massive influx of calcium into the cells resulting in hypocalcemia. The initial bite produces a pin prick were burning sensation and is often unnoticed. Within hours the bite site becomes red, cyanotic, urticarial and eventually a characteristic halo shaped target lesion.

Later, generalized symptoms develop – Patients will have regional lymphadenopathy near the bite site, as well as chest, abdomen and lower back pain. The pain of a Latrodectus bite can mimic that of appendicitis! Eventually, patients may develop flexor spasms, and writhe in pain. This is bad. What’s worse is the potential for hypertension, sweating, salivation, dyspnea and increased bronchosecretions along with convulsions. Untreated patients can have symptoms for up to seven days. Many will have pain in persistent muscle weakness for weeks. Bite victims should have ice applied to the bite wound. It is certainly a good idea to update their tetanus status. Antibiotics are not routinely recommended. Most patients have pain severe enough to require IV opiates. The relative hypocalcemia may be treated with calcium gluconate. This requires appropriate cardiac monitoring and the evidence is far from ironclad. Latrodectus specific antivenom and is available in Australia and Arizona, and is appropriate for patients in which opiates and benzodiazepines are ineffective. If possible consider administering the antivenom and to the very young, the elderly, The medically fragile and those with hypertensive and cardiac disease.

Relief Will come within 1 to 2 hours after administration. Reducing is rarely indicated. Many patients who received an defendant will have flulike symptoms or a serum sickness like presentation for 1 to 3 weeks following treatment. Finally it is important to note that any symptomatic pediatric patient with a black widow bite should be admitted for observation and pain control. The ICU is appropriate for any patient with cardiac compromise or convulsions. Brown Recluse Spiders These brown colored spiders are 1-5cm long and have a fiddle-shaped marking on their thorax. Brown recluse spiders are nocturnal hunters. They search for prey during the months of April through October and like to hide in small spaces like closets, attics, old blankets and shoes. Most bites occur on the extremities. More potent than the venom of rattlesnakes, the brown recluse bite leads to extensive skin necrosis. Sphingomyelinase-D causes RBC lysis. Once the cell walls are damaged and intravascular coagulation process leads to clotting abnormalities, White blood cell infiltration and eventually the the aforementioned necrotic ulcer. Fortunate patients will have a local irritating reaction, whereas the unlucky ones will have a life threatening syndrome.

The bite itself is relatively painless. Within a few hours there is itching, swelling, redness and tenderness over the bite. Initially the wound may appear to be a dull blue-gray macule surrounded by a pale ring. Eventually, by the third or fourth day the base becomes a chronic with a central black eschar. Full thickness necrotic ulceration occurs by 1-2 weeks. The above cutaneous reaction is much more common than systemic symptoms. Within 1 to 3 days after the bite patients have fever, chills, myalgias and arthralgias. Very severe cases result in DIC, hemolytic anemia, and dark urine. Management depends on whether or not the patient has local or systemic symptoms. Heat will worsen local symptoms so use ice. A polymorphonuclear leukocyte inhibitor (dapsone) may help with overall healing. It’s use is controversial in pediatrics due to the development of methemoglobinemia. Update the patient’s tetanus status if necessary. Whatever you do do not excise the lesion early on. this will just make things worse. Once the damage is done a plastic surgeon can excise and revise.

Patients with systemic symptoms may benefit from glucocorticoids as steroid treatment can slow hemolysis. Close monitoring for DIC is essential. Patients with hemolysis should have their fluid status monitor closely and one should consider alkalinizing the urine. An antivenin is being currently researched. Patients with a rapidly expanding lesion or hemolysis should be admitted. Patients with minimal symptoms and reassuring labs can be seen in 24-48 hours by their physician. Not Spider Bites Spider Bites - Injuries and Poisoning - Merck Manuals Consumer Version (See also Introduction to Bites and Stings .) Serious injuries from spider bites can include severe wounds caused by the tissue-destroying venom of brown spiders and bodywide poisoning caused by the nerve-toxic venom of widow spiders. Wounds suspected of being caused by the brown spider are often caused by other problems, some potentially more serious. Brown spider bites are treated by caring for the wound. Widow spider bites are treated by relieving symptoms and sometimes giving antivenom. Almost all spiders are poisonous. However, the fangs of most species are too short or too fragile to penetrate human skin.

Although at least 60 species in the United States have been implicated in biting people, serious injury occurs mainly from only two types of spiders: The widow (black widow) spider The brown (brown recluse, fiddleback, or violin) spider Brown spiders are present in the Midwest and South Central United States, not in the coastal and Canadian border states, except when imported on clothing or luggage. Widow spiders are present throughout the United States. Although some people consider tarantulas dangerous, their bites do not seriously harm people. Spider bites cause fewer than three deaths a year in the United States, usually in children. Symptoms The bite of a widow spider usually causes a sharp pain, somewhat like a pinprick, followed by a dull, sometimes numbing, pain in the area around the bite. Cramping pain and muscle stiffness, which may be severe, develop in the abdomen or the shoulders, back, and chest. Other symptoms may include nausea, vomiting, sweating, restlessness, anxiety, headache, drooping and swelling of the eyelids, rash and itching, severe breathing problems, increased saliva production, and weakness. Did You Know... Although tarantulas are large and may appear frightening, their bites do not seriously harm people.

The bite of a brown spider may cause little or no immediate pain, but some pain develops in the area around the bite within about an hour. Pain may be severe and may affect the entire injured area, which may become red and bruised and may itch. The rest of the body may itch as well. A blister forms, surrounded by a bruised area or by a more distinct red area that resembles a bull’s-eye. Then the blister enlarges, fills with blood, and ruptures, forming an open sore (ulcer) followed by a thick black scar (eschar) that may leave a large crater-like scar. Uncommonly, nausea and vomiting, aches, fatigue, chills, sweating, blood disorders, and kidney failure develop. Diagnosis A doctor's evaluation If possible, identification of the spider There is no way to identify a particular spider on the basis of its bite mark. Therefore, a specific diagnosis can be made only if the spider can be identified. Widow spiders are recognized by a red or orange hourglass-shaped marking on the abdomen. Brown spiders have a violin-shaped marking on their back.

However, these identifying marks can be difficult to discern, and the spider is rarely retrieved intact, so the diagnosis is usually uncertain and based on symptoms. Many people mistake skin infections, some potentially serious (such as methicillin-resistant Staphylococcus aureus [MRSA] infections), or other disorders for spider bites. Treatment Cleaning the wound and applying ice For widow spider bites, drugs to relieve pain and muscle spasms and often antivenom For brown spider bites, wound care and sometimes surgical wound repair First-aid measures for a spider bite include cleaning the wound, applying ice (for example, an ice cube or crushed ice in a plastic bag and wrapped in a thin cloth because ice should not be applied directly on the skin) to the bite to reduce pain, and, if the bite is on an extremity, elevating the wound site. For a widow spider bite, muscle pain and spasms can be relieved with benzodiazepines (which sedate and may help relax muscles) and opioids (analgesics). Antivenom is given for severe and sometimes for moderate poisonings (those that cause muscle cramping or other bodywide symptoms).

Hospitalization is usually required for people younger than 16 or older than 60 and for people with high blood pressure, heart disease, or severe symptoms. Did You Know... Many people falsely assume that they were bitten by a spider when they really have another disorder, such as a skin infection. Most brown spider bites heal without complications. Sores should be cleaned daily with a povidone-iodine solution and soaked 3 times a day in sterile salt water (saline). Moderately to severely damaged wounds may require surgical procedures. Resources In This Article Spiders and Insects - New River Gorge National River (U.S. National Park Service) Spiders and Insects Brown Recluse Poisonous Spiders Only two types of poisonous spiders may be found in the New River Gorge area; the black widow and possibly the brown recluse, whose range may be expanding into this area. While these spiders are rarely encountered on hikes or picnics, it is still important to be able to identify these spiders in case a bite is received. Brown Recluse: • Has a violin shaped mark on its back • A body length of 10 to 12 mm.

• 6 eyes instead of the typical 8 Habitat: • In or around abandoned buildings Indoors: • Storage rooms and crawlspaces. Symptoms: • Reaction varies from just a little red mark with no pain or other symptoms to more severe symptoms such as tissue damage and intense pain. • Itching, chills, fever, nausea, vomiting, shock • A small white blister usually forms at the bite site; the affected area may become red and tissue may be hard to the touch. • A dry blue-gray or blue-white lesion may form. • Red or orange hourglass shaped marking on the underside of its abdomen. Habitat: • Often found in buildings, wood piles, stone walls, and crawl spaces. Symptoms: • Severity of the reaction can vary • Venom acts on the nervous system, causing various degrees of pain • Short stabbing pain • Slight local swelling and two red spots (puncture points from the spider's fangs) • Pain progresses from bite site to abdomen and back • Nausea, profuse perspiration, difficulty breathing, tremors, increased blood pressure, fever • Symptoms usually diminish after a day or so Prevention: • Avoid sticking your hands in leaves, under rocks, or in places where you cannot see.

• Wear gloves when collecting firewood or moving rocks or yard debris. • When camping, shake out clothing and shoes before getting dressed. If bitten: • Carefully attempt to catch the spider so it can be properly identified. • Seek medical attention immediately. mosquito Mosquitoes Mosquitoes are a very common menace through out the New River Gorge area. While most mosquitoes are harmless, some do carry diseases such as West Nile Virus. West Nile Virus: West Nile Virus is a potentially serious illness. For more on the symptoms, prevention, and what to do if you believe you may have contracted the virus please visit the Center for Disease Control website via the link below. Habitat: Mosquito’s are found in a greater number around bodies of water such as streams, rivers, ponds, and lakes. While their numbers will be greater in these areas, mosquitoes can be found throughout the area due to their ability to lay eggs wherever standing water may be found. Prevention: The most efficient means to control mosquito populations and the spread of diseases carried by them is to reduce the amount of locations where they may lay their eggs. Mosquitoes require a water source to lay their eggs. Eliminating standing water will help to reduce populations.

Mosquito habitat can often include: • Garbage Cans and Recycling Bins • Litter such as soda bottles and cans • Tires • Use insect repellants with DEET, according to manufacturer’s instructions. • Wear long sleeves and long pants when possible. • When possible remain indoors at dawn, dusk, and in the early evening when mosquito’s are most active. • Ensure window screens or tent netting is in good condition. Deer Tick Ticks Ticks are blood-feeding parasites that are often found in tall grass and shrubs where they will wait to attach to a passing host. Physical contact is the only method of transportation for ticks. Ticks do not jump or fly, although they may drop from their perch and fall onto a host. Ticks will try to climb to the highest part of their host. Habitat: Ticks can be found in most wooded or tall grass land regions throughout the world. They are especially common in areas where deer are plentiful. Commons ticks here: This tick can carry Rocky Mountain Spotted Fever • Deer Tick This tick can spread Lyme Disease Description: • Unfed males and females are reddish-brown and can be 3/16-inch long or smaller.

They have hard shells, starting right behind the mouth. Prevention: • Wear protective clothing such as long-sleeved shirts, long trousers, boots or sturdy shoes. (Ticks are easier to detect on light-colored clothing.) • Apply insect repellent containing 10 to 30 percent DEET primarily to clothes. Apply sparingly to exposed skin. Always follow label instructions on how to apply. • Walk in the center of trails so weeds do not brush against you. Individuals who sit on the ground or disturb leaf litter on the forest floor may encounter ticks. • Check yourself, children and other family members every two to three hours for ticks. Most ticks seldom attach quickly and rarely transmit disease organisms until they have been attached for four or more hours. If your pets spend time outdoors, check them for ticks, too. • Take a shower immediately after coming in from being in the outdoors. Removal of tick: • If tick is on clothing use masking or duck tape to remove. • The best way to remove a tick is to grasp it firmly with tweezers as close to the skin as possible and gently, but firmly, pull it straight out. • Do not remove the tick with bare hands.

• To dispose of the tick, flush it down toilet. • Wash the area around the bite thoroughly with soap and water, then apply antiseptic to the bite. • If you have an unexplained illness with fever, contact a physician. Be sure to tell the physician if you have been outdoors in areas where ticks were present.

Question: What type of spider can be identified by an hourglass-shaped mark on its abdomen?
Answer: Black Widow