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Images Dr. Kaae.

Order Aranea.  All spiders are included in the order Aranea.  Spiders have 4 pair of legs, no antennae and from 1 to 4 pairs of eyes.  As in all arachnids, the first pair of appendages behind the mouth is called chelicerae and in spiders these appear as hollow fangs.  Poison glands are connected to the fangs which are used to subdue prey.  Spiders feed by external digestion.  When a spider bites its prey, it injects venom and a digestive enzyme.  The function of the digestive enzyme is to dissolve the internal parts of its prey so the spiders can subsequently “suck it dry” with its hollow fangs.  Most species of spiders are relatively harmless to humans.  In fact, the fangs of most spiders are too small and weak to penetrate thicker human skin or in many cases even the thinest of human skin.  The bites of a few species of spiders are potentially harmful to humans.

Black Widows and Related Species. The black widow spider is found in every state of the country, and there are similar species throughout much of the world.  There are 5 or 6 species of widow spiders belonging to the genus Lactrodectus in the United States.  Each is marked slightly different, and all have a fairly toxic bite. 

Western Black Widow, Lactrodectus hesperus.  This is the species most commonly associated with the name black widow in the Western United States. 

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Female Black Widows, Lactrodectus hesperus.Left  Image Dr. Kaae. Right Image Gravid or Full of Eggs. Courtesy James Gathaway CDC Photo Library.

Only the female of the species is dangerous and is named after the practice of killing the male immediately after copulation. In actuality, the female is usually pretty well-fed, and more times than not the male escapes before being consumed.  As with many spiders, males are many times smaller than the females and brownish in color with pearly markings on the top of the abdomen.  As with many spiders, the male’s pedipalps are club-shaped, quite large and used to transfer sperm to the female.

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Male Black Widow with Clubbed Pedipalps. 

The immature females are often brown and striped with colored markings. All stages (except the youngest spiderlings) have a red marking on the underside of the abdomen. This red marking serves as a warning coloration to any potential predators.  Bright colors in most animals serve the same function by advertising the fact that this animal is potentially dangerous and to stay away.  The black widow female hangs upside down in her web, thus making this marking clearly visible.

The female is nocturnal and lies in wait on or near the web for passing prey. The male typically is not found in the web and searches either for prey or a female. The web is characteristically asymmetrical in shape, strong and produces a crackling sound when probed.  In the spring, the female can produce from 1 to 8 marble shaped white egg sacs.  Depending of prevailing temperatures, these eggs can hatch within 10-20 days. The spiderlings remain inside the sac until they molt into the second instar. This may take in up to a month or more depending on temperature.  Each sac can contains as many as 200 spiderlings but normally there is considerably less.  Once emerged, they initially forage and do not use webs to catch small arthropods, such as mite and aphids. The entire life cycle is completed in 4 to 8 months with the adult typically living about a year. These spiders can be found in many situations but common environmental requisites include high humidity, food and dark protected locations.

As with other spiders, black widows balloon or parachute as spiderlings. They typically crawl up on a twig or high on another surface, point their abdomen upwards and shoot long strands of silk out of their spinnerets.  Air currents pick up this webbing and carry off the attached spiderlings. With the heat of the day, the floating spiderlings are carried upward as high as a mile or so.  As temperatures cool and wind turbulence decreases at night, they float back to earth.  If they reach favorable environmental conditions, they survive.  If they do not, they die. In actuality, very few young survive to adulthood. However, because the female can produce as many as 2,000 or more during her lifetime, only 2 need to survive to replace the parents and perpetuate the species.

Apparently these young spiderlings and other small spiders have been observed (caught in ship sail) as far as 600 miles from land.  In addition, they have been found in air samples collected with atmospheric data balloons as high as 2 miles. It has been postulated that this is a common mechanism for spiders to invade isolated islands or tops of isolated mountains. Another common means would be human trafficking. Spiderlings have been recorded to survive without food while traveling in air currents for 25 days or more.

These spiders are not typically aggressive except in defense of the egg sacs.  It follows that this would normally occur in the spring, as this is when these egg sacs are formed. The fangs of a black widow are quite small and incapable of penetrating thick human skin.  This is common with many species of spiders.  As a result, a black widow must bite you on the soft parts of your body.  The bite of this spider is rather painless at first; however, a systemic effect soon develops because of a strong neurotoxin. The toxin of a black widow is said to be 15 times as toxic as that of a rattlesnake.  However, there is much less toxin so the bite is not nearly as bad as that of the snake.  Pain typically starts 1 to 3 hours after the bite and can continue for 24 to 48 hours.  Pain often starts in the lymph nodes (groin, armpits) and spreads to the lower back. A diagnostic symptom is the development of severe chest cramps due to rigid contractions. Clammy skin, a drop in blood pressure, excess sweating, facial muscle spasms, difficulty in breathing and convulsions are additional symptoms. The mortality rate of the bite of an adult female black widow in humans is approximately 5% of untreated cases.  Most of these deaths occur in young children (more venom per body mass) or individuals who are already in poor health.

The most common location where black widow bites occur in Southern California is outdoor bathrooms.  Right under the toilet seat it is dark, humid and abounds with flies. As previously indicated, these are all preferred environmental conditions of these spiders.  In the springtime, when the female is guarding her egg sacs and someone wiggles her web with soft body parts, it can be quite surprising (ouch!). 

An antivenin is available for black widow spider bites. This is not always given. Under normal circumstances, it is only administered one time.  Frequently patients are provided Demerol or something else for the pain, if the bite symptom do not appear to be too serious or life threatening. The antivenin is quite effective; however, it is not always advisable to use it on all patients, as some may develop allergic reactions.

The black widow antivenin is produced twice a year by a fairly simple procedure. There are several small companies (actually most are basement of houses) that raise black widows by the thousands.  As the result of applying a mild electrical shock, the spiders exude a tiny drop of venom from each fang or chelicera. These tiny drops of venom are subsequently collected with small capillary tubes and saved.  In the U.S., the venom is pooled twice a year to produce antivenin. This is accomplished by injecting small amounts of the venom into horses. These animals possess a degree of natural immunity to the black widow toxin and are not harmed.  Subsequently, in a week or 2 when the horses have developed even more immunity as a result of exposure to the venom, serum is condensed from their blood to make the antivenin. As previously mentioned, individuals treated with antivenin may develop allergic reactions. One such reaction is to develop hives and other symptoms when eating beef.  Apparently, at least some of the protein in beef is the same or similar to that in horse blood serum.

Brown Widow Spider-Latrodectus geometricus.  This spider is also commonly known as the grey widow or brown button spider. The brown widow is found in parts of the southeastern, south and southwestern U.S. These include Florida, Alabama, Oklahoma, California, Nevada, Louisiana, Georgia, Mississippi, South Carolina, Arizona, Tennessee, New Mexico and Texas.  It has recently received considerable attention, and has been accidentally introduced Orange County, California and other parts of the country.  The origin of this species is uncertain. Specimens were independently discovered in both Africa and in the Americas. They are usually found around buildings in tropical areas. In many areas, the distribution of the brown and black widow overlaps.  In this case, indications are that the brown widow out competes and tends to replace the black widow.

There brown widow is generally lighter in color than the black widow. Its color can range from tan to dark brown to black with shades of grey also possible. Like the black widow species in the United States, it has a prominent "hourglass" marking on the underside of the abdomen.  The brown widow's hourglass is usually a vivid orange or a yellowish color. Unlike the black widow, the brown widow has a black-and-white "geometric" pattern on the dorsal side of its abdomen. Although the Latin name comes from this pattern, the spider's coloring can and does darken over time, and the pattern may become obscured.

Brown widows can be located by finding their easily identifiable egg sacks. They resemble a sandspur having pointed projections all over, and are sometimes described as "spiky" in appearance. Eggs hatch in approximately 20 days.

Like all widow species, this brown widow is medically significant with neurotoxic venom. Some experts claim that brown widow venom is 2 times as potent as that of the black widow venom, but is usually confined to the bite area and surrounding tissue and typically lacks systemic effects. Other sources say that the brown widow is less venomous than the black widow.  Regardless, individuals who have been bitten typically describe the experience as very painful and care should be taken when working or playing in the areas they inhabit.

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Brown Widow Females with an Asymmetrical and Spiked Egg Sac. Left Image Dr. Kaae.  Right  Image Courtesy Mfield, Matthew Field, http://www.photography.mattfield.com GNU Free Documentation.

Brown Recluse or Violin Spider. Loxoceles reclusa. This spider is known as the fiddleback, recluse and violin spiders. This species is commonly found in the central and south-central U.S. Loxoceles laeta or the Chilean brown spider (also known as the South American violin) was found in Los Angeles a number of years ago but recent identifications are non-existent.  There is also considerable controversy as to if the brown recluse spider still exists in California.  The medical community annually reports treating many bites from the recluse spider. However, spider experts claim this spider no longer exists in California. Because little is known about the effect of the bite of many spider species, it is quite possible that the medically treated cases are not due to the recluse but any of a number of other spiders or more commonly to bacterial skin infections. The latter is especially possible when allergic reactions are considered.

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Complete distribution range of wild and domestic Loxosceles recluse. Image Courtesy Bob the Wikipedian Public Domain.

This species is typically between ¼ in and ¾ inch in length but may grow to considerably larger sizes. They vary in coloration and may be brown, gray, or a deep yellow and usually have violin shaped markings on top of the cephalothorax. As a result, the common nicknames are fiddleback spider, brown fiddler and violin spider. The violin pattern is not diagnostic, as other spiders may have similar markings (pirate spiders). Positive identification can be made by the number and arrangement of the simple eyes. While most spiders have 8 eyes, recluse spiders have 6 or 3 pair that are arranged in an upside down or semicircle pattern with 1 median and 2 lateral pairs. Very few spiders have 3 pairs of eyes arranged in this manner. The abdomen bears many fine short hairs.  

Behavioral characteristics of this spider can also be used in identification. When standing on a flat surface, all legs are typically extended.  If they are defensive, they withdraw the front legs straight backwards. At the same time they withdraw their rear legs into a position for lunging forward. Movement is an evenly paced with legs extended. When threatened, they typically withdraw and apparently to avoid conflict.  If they are confined or detained, they try to avoid contact with rotating movements.

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Adult Recluse and Eye Pattern.  Left Image Courtesy of Rosa Pineda CC BY-SA 3.0. Right Mattb. Public Domain.

The web of these spiders is asymmetrical in shape and may include a shelter for retreat that consists of disorderly silken threads. These spiders are frequently found in woodpiles, sheds, beds, closets, garages, cellars and other places that are dry and typically undisturbed. They are frequently found in cardboard in homes. This is possibly due a similarity in texture to rotting tree bark which is their natural habitat. They also have been encountered in shoes, beds, dressers, bed sheets of infrequently used beds, stacks and piles of clothing, underneath baseboards, pictures, and near sources of warmth when it is somewhat cold. Bites commonly occur when the spider is disturbed or is threatened. Unlike most web spiders, males leave their webs at night to hunt, but the female tend to remain nearer to her web.

The brown recluse spider is native to the U.S. and ranges from the southern Midwest south to the Gulf of Mexico. It is native to central Texas to western Georgia and very common in the Northwest.  A related species, the brown violin spider is found in Hawaii. Despite many rumors, the brown recluse spider has not become established or even been found in California in the past 20 years. There are other species of this genus that are native to California that may resemble the brown recluse, but these species are rarely encountered with a bite that is not considered dangerous to humans.

Symptoms. As suggested by their name, this species is typically not aggressive and bites are rare. It usually bites only when threatened or pressed against the skin. This can occur if it is tangled up within clothing, shoes, or in bedding. Many human bites have occurred after putting on clothes which had not recently been worn.  Many wounds that have been attributed to brown recluse spider bites have actually been the result of methicillin-resistant Staphylococcus aureus (MRSA) or other Staphylococcus infections. Other misdiagnosed recluse spider bite symptoms include Lyme's disease, and infected insect bites.  Bites from this spider can produce a variety of symptom known as loxoscelism. There are two main types of loxoscelism, namely cutaneous and systemic viscerocutaneous.

Most bites from a brown recluse spider are minor with no local skin necrosis. However, a small number can result in severe necrotic skin lesions and on occasions systemic symptoms. These can include organ damage and occasionally even death with most deaths occurring in young children or individuals with a weak immune system.  On occasion, brown recluse spider bites result in large necrotic ulcers that destroy tissue and take months to heal. These wounds can produce large deep scars. Damaged tissue can become gangrenous and rot away. The initial bite is not typically felt or there is little or no pain, but in time the necrotic areas grow to as large as 12 inches in extreme cases. Bites are typically painful and itchy within a few hours. These symptoms typically worsen in an average of 24 hours after the bite and necrosis develops over the next few days.

Numerous other spiders have been associated with necrotic bites. The most common of these are the hobo spider and the yellow sac spiders. Fortunately, bites from these spiders do not typically produce the severe symptoms that is typically associated that of a brown recluse. There are several studies that question the danger posed by these two spiders.

A recent article in National Geographic News illustrates how common it is to mistake brown recluse bites for a number of other maladies. “Many diagnoses of brown recluse spider bites come from areas apparently outside of their habitat. Brown recluse spiders are found mostly in the central and southern U.S., an area that includes Texas, Arkansas, Missouri, Kentucky, and Tennessee, parts of Illinois, Indiana, and Georgia. Brown recluse spiders also inhabit the states bordering the Gulf of Mexico. Yet Vetter (a UCR spider expert) has fielded reports of brown recluse bites from Wisconsin, New York, even Alaska and Canada. In virtually every case, systematic searches in those places have turned up no brown recluse spiders. In one analysis, Vetter counted 188 reports of brown recluse bites in 3 years in California, Oregon, Washington, and Colorado. But only 15 brown recluse spiders have ever been found in those four states. "These bite diagnoses are everywhere, and yet no one can find the spider," Vetter said. "Show me the spider."

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Symptoms of Brown Recluse Spider a Few Days after Bite.  Image Courtesy of Center for Disease Control.

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 Scar Left from Brown Recluse Bite. Image Courtesy of Center for Disease Control.

Tarantulas. Tarantulas have received a “bad rap” from the moving picture industry for years.  Actually in most cases the bite of a tarantula is relatively harmless to humans. That is to say, the venom has little more effect than that of a bee sting.  Of course, since tarantulas are so large, it follows that their chelicerae or fangs are large. In some of the larger tarantula species of the world, these structures can reach 1 inch in length. In this case, a bite would result in a deep puncture wound and should be treated with a tetanus shot.  As with many species of spiders, little is known about the toxicity of the venom of many tarantula species. This knowledge is becoming increasingly important because of the recent interest in keeping tarantulas as pets. There are many tarantula breeders in the United States and Europe. These individuals conservatively breed over 100 species of tarantulas for the pet and spider enthusiast trade.

Besides biting, New World tarantulas frequently protect themselves by using their hind legs to kick off puffs of branched body hairs (urticating hairs) from the back of their abdomens. The mucous membranes of the eyes and nose of mammals, including humans are quite sensitive to these hairs and contact results in watery eyes and severe itching of the skin that may last for several hours. These hairs can penetrate the skin up to 1/16 inch and frequently have toxins associated with them. Individuals who handle tarantulas may develop an allergic reaction to this venom that may result in increased sensitivity and irritation after minimal contact. Because the venom in the hairs is likely to be the same as that in the fangs, someone who has developed sensitivity to the hairs could have a more severe reaction upon being bitten. The hairs are regenerated each time the tarantula molts.

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Top of Bald Abdomen Missing Urticatig Hairs. Image Courtesy HTO. Public Domain.

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Nicely Marked Species of Tarantula and Chelicerae or Fangs of an Average Sized Tarantula. Images Dr. Kaae.

Goliath Spider. The goliath spider from South America is the largest species of spider in the world. A large specimen with its legs fully spread will exceed the size of a dinner plate (10 inches). Some of these giants of South America feed almost exclusively on lizards, frogs and snakes.This spider is commonly referred to as a bird eater. This is a misnomer. These ground inhabiting, heavy bodied spiders are rather slow moving and cannot climb, all characteristic which would be detrimental to catching birds.  Apparently, this name was probably acquired because one of the original books published about spiders had a drawing of this spider sitting next to a dead bird. When given a choice, this tarantula prefers rodents to insects. Some of the more primitive human tribes actively seek these giant tarantulas of the rainforests as a food source; the spiders are roasted to remove the body hair. The eggs of a gravid female are a special treat making a nice omelet! Tarantula is said to taste like chicken; actually, it has a distinctive flavor of its own-I guess (haven't eaten that many).

On one occasion, we received a live adult female goliath spider. As one of my colleagues and I were observing the spider, I asked him, "Do you want to hold it?" He responded rather abruptly, "No!"  I replied, "Me neither, let's feed it." It was a real monster with at least 1-inch long curved fangs. So we proceeded to throw a large mouse in its cage. The spider immediately jumped on the mouse and began pumping in salivary enzymes with its 1 needle shaped fangs. Upon our return the next day, there was nothing left but a small ball of fur. The tarantula had dissolved and consumed everything else including the bones.  We never handled that one-Ever.

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Top. Goliath Tarantula with Its Legs Spread. Image Dr. Kaae. Right. Fried Tarantula in Cambodian Restaurant. Image Courtesy Jaiprakashsingh at English Wikipedia CC BY-SA 3.0

Most tarantulas in the United States feed on insects and possibly young rodents. There are a number of tropical species that live in trees (arboreal) and possibly feed on young birds (the bird spiders). Many of the bird spiders are relatively slender bodied and exceedingly hairy with long hairs extending at right angles from the body. The authors were not sure of the function of these hairs until one day we accidentally dropped a rather hairy one. While in midair, the spider extended its legs in all directions and floated to the ground--much like a falling leaf. The long hairs obviously increased the surface area of the spider and along with the spider's relatively light body, allowed it to perform this acrobatic feat--a behavior that obviously has advantages when living in trees.  The main diet of bird spiders is not birds but insects.

Mexican Red-Knee. This is one of the most brightly colored and docile tarantulas. This species was collected by the thousands from Southern Mexico and imported for years into the United States for the pet trade. Several years ago, the Mexican government prohibited this practice due to the depletion of the species. Mexican red-kneed tarantulas occasionally can still be found in pet stores, but these come from tarantula breeders. They are typically available as tiny spiderlings.

The importation and exportation of animals and plants and/or their parts (e.g., Mexican red-knee, animal horns, and spotted cats) in many countries throughout the world has become a major problem. As a result, a number of these countries have formed an international agreement called the CITES Agreement.  Each country has identified the plants and animals (including their parts) which they want to protect. Once placed on a CITES List, an organism cannot be exported from a country to another country without a permit from the country of origin. In many cases these permits are not available. In the United States, the Fish and Wildlife Service enforces this agreement.  If they catch someone importing an illegal CITES organism, the penalties can be quite severe. An individual recently was caught bringing into the U.S about 80 Mexican red-knee tarantulas. He was incarcerated and heavily fined.

There was a case where an individual was caught trying to import a number of illegal butterflies (CITES) including 2 Queen Alexander birdwings-largest butterflies in the world-valued at $8500 each.  He was convicted on 15 Federal charges as a result of a 3 year investigation by the Federal Fish and Wild Life Services.  This individual was a fairly well-known insect dealer.  I knew him well. He seemed nice.       

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 Female Red Knee Tarantula. Image Dr. Kaae.

Chilean Rose Haired. The authors were somewhat skeptical about reports of a few incidences where a tarantula attempted to heal its own wounds with its webbing. However, one day we were closing the cage door of a Chilean rose-haired tarantula and accidentally chopped off part of its leg. As blood began to ooze from the wound, the tarantula spun several strands of silk and wrapped it around the wound, thus effectively sealing it. Without this tourniquet, the tarantula would likely have bled to death.

The Chilean rose-haired tarantula is the most common species sold in pet stores. This spider is typically quite docile and in most cases are reluctant to bite. However, there are always exceptions. My wife Pat used to offer insect presentations to schools. Unfortunately, one day she accidentally dropped the tarantula she was using in these presentations and cracked its exoskeleton. As with insects, spiders have an “open” circulatory system where the blood is contained within the exoskeleton but little within blood vessels.  As a result, if the exoskeleton is cracked, the spider may bleed to death and ours did. I learned since then, if a spider’s exoskeleton is cracked and there is no of minimal internal damage, the spider can be saved by sealing the crack with Super Glue.

When we at our Insect Fair at Cal Poly, one of the vendors indicated the Chilean Rose Hairs are quite docile and would be of use on Pat’s presentation. I took the spider he had and handed it to my wife.  Very shortly thereafter the spider bit Pat. She was pretty cool about it and indicated the spider was biting hers. At that time, we weren’t aware of how toxic were tarantula bites. I didn’t tell her that and had to leave. I did call her a few hours later to see how she was doing. It wasn’t a big deal, but she did have a strong tingling sensation on the hand that was bitten; that feeling subsequently traveled up her arm across her shoulders and down the other arm.  She does have a small hole in her hand where the tarantula tried to dissolve her-much like they do to their prey.

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Chilean Rose-haired Tarantula-the Most Common Species Available in Pet Stores. Image Dr. Kaae.

Jumping Spiders.  Some jumping spiders are reportedly very aggressive and on occasion bite humans. The venom is not very potent and the bite is initially painful leaving 2 small red marks that heal in a few days.  Johnson’s jumping spider is the most common species that has been reported to bite humans.  C:\Users\PatK\Pictures\Euophrys_kataokai_DSC_8526 Adorable Jumping Spider Japanese.jpgMalePeacockSpider.jpghttps://upload.wikimedia.org/wikipedia/commons/thumb/5/5b/Marpissamuscosa.jpg/1024px-Marpissamuscosa.jpg

Nice Jumping Spiders. Top.  Europhrys kalaokai. Image Courtesy Yasunori Koide - Own work, CC BY-SA 3.0.  Left. Peacock Jumping Spider. Image Courtesy Jugen Otto By CC BY-SA 2.0. Right Courtesy Atalanta CC BY SA 4.0.

This family contains more than 500 described genera and approximately 5,000 described species. This makes it the largest family of spiders with approximately 13% of all known species. They have excellent vision which they rely on for hunting and navigating. They are capable of jumping from place to place but are secured by a silk tether. Jumping spiders live in a variety of habitats with tropical forests harboring the most species, but they also commonly occur in temperate forests, scrub lands, deserts, intertidal zones, and even mountains. They are generally diurnal, active hunters. They possess a well-developed internal hydraulic system which alters the pressure of body fluid within their legs, thus allowing the spiders to jump without large muscular legs. Some jumping spiders can jump 40 times their body length. This is equivalent to a 6 foot man jumping 240 feet.  When moving and especially just before it jumps, the spider tethers a filament of silk to any available surface. Should it fall, it can then climbs back up the silken tether.

Jumping spiders are known for their supposed curiosity.  If approached by a human hand, instead of retreating to safety as most spiders would, the jumping spider will usually leap and turn to face the hand. Further approach may result in the spider jumping backwards while still eyeing the hand. The tiny creature will even raise its forelimbs and hold its ground. Because of this contrast to other arachnids, the jumping spider is regarded as inquisitive as it is seemingly interested in whatever approaches it.

An additional distinctive characteristic is their large eyes. These spiders have the best-developed visual system of all spiders and is used their advantage when hunting prey. As do most spiders, they have 4 pairs of eyes. One large pair and one small pair are oriented in a forward facing position. Above this front row is a second row of 2 tiny eyes and behind these there is a set of 2 large eyes oriented in an upward position. As a result, these spiders can see in a 360-degree plane.  Unlike other spiders, they can move their eyes outward or inwards for focusing and they can be turned up and down and from left and right. The spider can also turn its carapace (breast) more than 45 degrees to look around. Jumping spiders have very good vision that is centered in their anterior median eyes. Their eyes are able to create a focused image on the retina which has up to 4 layers of receptor cells. Physiological experiments indicate that they have up to 4 different kinds of receptor cells. These include those with different absorption spectra and provide the possibility of up to tetrachromatic color vision. This sensitivity extends into the ultraviolet range. All of these spiders are highly sensitive to UV light. The principal eyes have high resolution, but the field of vision is narrow.

Jumping spiders are active hunters and stalk their prey. They use their discussed superior eyesight to distinguish and track their intended meals. Then they pounce giving the insect little to no time to react before succumbing to the spider's venom.

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Jumping Spider with Heavily Fringed Palps for Mating Display. Image Courtesy of Peter Chew, Brisbane Insects.

Mating recognition depends on visual courtship displays. Males are often quite different in appearance than females and may have branching or iridescent hairs, front leg fringes, structures on other legs and other bizarre, modifications. These are used in visual courtship in which the colored or iridescent parts of the body are displayed via vibrations, or zigzag movements for courtship a "dance". If the female is receptive to the male, she will assume a passive, crouching position. In some species, the female may also vibrate her palps or abdomen. The male will then extend its front legs towards the female to touch her. If the female remains receptive, the male will climb on her back and inseminate with his palps. In recent years, it has been discovered that many jumping spiders may have auditory signals as well.

Trapdoor Spiders. Trapdoor spiders construct burrows with a trapdoor made of soil, vegetation and silk. These relatively large spiders (adults reaching 1 to 1.5 inches in length) are rarely seen as they spend the majority of their lives in well-designed tunnels in the ground. The only time that a trap door spider is commonly seen is when the male reaches sexual maturity and strikes out in search of a female.  Otherwise, they remain, grow and molt inside their tunnels.The entrance of the tunnel is typically covered by an earthen door that is hinged at one end.  The door is extremely difficult to spot and it blends in with the surrounding environment.

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Trap Door Spider. Image Dr. Kaae.

Trap door spiders do not leave their burrows to hunt but merely wait with the door partially open for passing prey. Their eyesight is not well-developed, and they rely on sensitive hairs on their legs to pick up vibrations of passing prey.  Some species actually place elongated twig or silken strands radiating out from the entrance which function to detect passing prey.

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Door of a Trap Door Spider with Silken Stands Radiating Outward to Detect Potential Prey. Image Dr. Kaae.

The burrow and door serve not only as a home and means to capture prey, but also protects the spiders from rain, regulates humidity and temperature and helps protect them from potential predators such as centipedes, scorpions and parasitic wasps. In some species, these spiders have sets of spines on their legs which presses into the side of the burrow while it holds the door shut with its fangs.  We once tried to pry open the door of one of these spiders with a spoon and actually bent the handle in doing so. It is now known that these spiders can withstand the pull of 38 times its weight.

 A hungry individual will wait halfway outside of its burrow for a meal.  Females never travel far from their burrows, especially if they have an egg sac. During breeding season, the female will capture food and regurgitate it to feed her spiderlings. Enemies of the trapdoor spider include certain pompilids (spider wasps) which seek out the burrows and manage to gain entrance.

Some species store the remains of their prey and other debris behind the silk lining of the tunnel. If a potential predator breaks into the tunnel, the spider will rush to the bottom of the tunnel while simultaneously releasing the debris and silk lining.This material forms a false bottom to the tunnel and conceals the spider beneath.

Hollywood Trapdoor Species. Aptostichus stephencolberti is a species of trapdoor spider named after the American satirist Stephen Colbert. The spider was discovered on the California coastline in 2007. This species is found on coastal dunes that extend from the Big Sur area to the San Francisco Peninsula at Point Lobos and Golden Gate. Compared to closely-related species such as Aptostichus angelinajolieae (named after Angelina Jolie), Aptostichus stephencolberti is lighter in color. The male and the female both have brownish yellow legs, carapace and chelicerae while the abdomen is lighter with dusky stripes.

Orb-Weaver Spiders. These spiders are best known for their webs that are constructed of sticky spiral capture silk. Constructing their web is a feat of engineering and starts when the spider floating a line on the wind towards another surface. Once this web is secured to a surface, the spider drops another line from the middle of the initial silken line thus producing a "Y" shape.The remainder of the support scaffolding follows with the production of many radii (circles) of non-sticky silk. Subsequently, it produces final spirals of sticky capture silk. The spider navigates the web by walking on the non-sticky part of the web. Characteristically, any prey insect that blunders into the sticky lines is stunned by a quick bite and then wrapped in silk. If the prey is a venomous insect, wrapping may precede biting.

Many orb-weavers build a new web daily. The spider will consume the old web, rest for approximately an hour, and then spin a new web in the same general location. As a result, their webs are generally free of the accumulation of detritus that is common to other species such as black widow spiders.

Some of these spiders do not build webs. These spiders have a rather unique means of catching their prey. Instead of building webs, they attract their prey (male moths) by chemical mimicry. Moths are captured using a "bolas", which is a sticky ball of glue attached to a strand of silk. The spider swings this around until the ball hits and sticks to an approaching moth. The moth is then reeled in by the spider and then webbed up in silk. This would be a pretty inefficient means of capturing prey if done at random. The chance of catching a moth that merely flew by would be pretty remote. However, the spider actually emits a sex pheromone that mimics that produced by female moths to attract males for mating. Instead of finding a mate, the males end up as dinner for the bolas spider. Even more amazing, this spider feeds on 2 different species of moths each of which fly and typically mate at different times of the night--one early in the evening and another late at night.  Accordingly, the bolas spider produces and releases 2 different pheromones each at the correct time that correspond to when each species of moth flies.

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Australian Female Bolas Spider and an American Bolas Spider Swinging Its Sticky Ball.  Images Courtesy of Dave Britton.

An equally amazing feature of this spider is the huge size of their egg sacs.Typically several of these giants are produced by the female. It is thought that she is capable of doing this due to the small amount of silk used in catching her prey.

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Female Bolas Spider Sitting on One of Its Several Egg Masses. Image Courtesy of Dave Britton.

One structure found in webs of a few orb-weavers is the stabilimentum. This consists of crisscross bands of silk through the center of the web. It is found in a number of genera, but Argiope including the yellow and banded garden spiders of North America are a prime examples. The functions of the bands have been hypothesized to lure prey or as a marker to warn birds away from the web or as camouflage for the spider when it sits in the center of the web. However, recent research suggests that the stabilimentum actually decreases the visibility of the silk to insects, thus makes it harder for prey to avoid the web. 

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Orb Web Spiders with Stabilimentum. Left Images Courtesy Peter Chew, Brisbane Insects. Right. Courtesy Muhammad Mahdi Karim-GNU Free Documentation.

Golden Web Spiders. .Anyone who has been in the tropics has undoubtedly come across the golden web spiders in the genus Nephila. These are beautiful monsters. The adult females of some species can reach a body length of two inches with a leg span of eight.  They are quite beautiful with many iridescent colors.  In comparison to the females, the males are minute.  In some species, they are 1,000 times smaller than the female.  The males are normally found in the same web as the female, but they are not in danger of being eaten because they are so small that the female does not recognize them as food.

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Typical (Costa Rican) Golden Orb Web Spiders.   Note Small Male at Top of Image. Courtesy Coveredinsevindust at English Wikipedia CC BY-SA 3.0

As amazing as are these spider, their web is even more impressive. The silk itself is a golden color and quite strong.  The silk is so strong that birds, bats and lizards are frequently trapped. The webs themselves are large, with the central hub reaching 6 to 8 feet in diameter and the radiating supporting strands attach as much as 20 feet apart.  The webs are so extensive that these spiders typically do not make new webs but continuously repair the old ones.  The webbing is so strong that the natives in some of the Pacific island use it for fishing line.

As large as these spiders are, they are not impervious to competition or even predation from other spiders.  On one of our student trips to Thailand, I was walking along a trail in the mountains and came across a large female Nephila spider that had recently caught and was feeding on a small bird.  I noticed that there were 2 other spiders (about 1/20th her size) feeding on the same bird.  Apparently, there are a number of other spiders that “pirate” feed on the prey of this species.  Argyrodes, a close relative of the black widow, is one of the main spiders that exhibit this behavior.  This spider typically builds its web close to that of the golden web spiders but makes frequent excursions onto the web of the giant.  Once this pirate determines that Nephila has made a catch, it waits until the prey is subdued, tightly wrapped with the giant's silk and moved to a storage location on the web. At that point, Argyrodes carefully moves toward the prey avoiding vibrating her web so not to end up as dessert.  Once locating the prey, Argyrodes cuts the filaments that support the wrapped package and steals away with its prize.  The orb spider’s web is so large that it is not uncommon for up to 40 of these pirates to feed off its catch.  If pickings are slim, these pirates on occasion will attack and eat the orb spider.

Lynx Spiders. These spiders hunt for their prey and as a result spend their lives on plants. They are quite nimble and readily jump. They rely on their keen eyesight to stalk, run down or ambush prey. Six of their eight eyes are arranged in a hexagon-like pattern. They are frequently characterized by long spiny legs.  Two of the most common genera in the U.S. are Oxyope the common lynx spider and Peucetia, the green lynx spiders. Some lynx spiders are common enough to be important in agricultural systems as biological control agents. This is especially true of the striped lynx spider (Oxyopes salticus).  Some in the genus Tapinillus are remarkable and are social spiders living in colonies.

The female of the common green lynx spider reaches a body length approaching an inch; the more slender male averages ½ inch. There usually is a red patch between the eyes and red spots over the body. The eye region is clothed with white flattened hairs. The legs are green to yellow with very long black spines and are covered with black spots. It is rather similar to other species to occur in the United States. Gravid females are able to change their color to fit their background; however, this takes about 16 days.

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Green Lynx Spider is Capable of Spitting Its Venom a Few Inches.  Image Courtesy of Chen-Pan Liao CC BY-SA 3.0.

The female constructs one to four egg sacs in September and October with each containing 25 to 600 bright orange eggs which she readily guards. They typically hang upside down from a sac and attack everything that comes near. The eggs hatch after about 2 weeks, and after another two weeks fully functional spiderlings emerge. They pass through eight instars to reach maturity. This non-venomous spider is usually found on foliage.

The green lynx spider very seldom bites humans, and its bite is relatively harmless though painful. It is a common predator in cotton and other crops. This species is found in gardens, chaparral, on flower heads of wild buckwheat.  The green lynx is capable of biting and spitting its venom a distance of a few inches.  If it reaches the eyes, the venom may cause irritation that will clear up in a few days. These spiders have been observed hunting several moth species and their larvae. These include some of the most important crop pests including bollworms, cotton leafworms and cabbage loopers. However, they also prey on beneficial insects such as honeybees.

Wolf Spiders. These spiders are robust and agile hunters with good eyesight, but unlike wolves, they live mostly solitary lives and hunt alone. Some are opportunistic wandering hunters and pounce upon prey as they find it or chase it over short distances. Others lie in wait near the mouth of their burrows.

These spiders resemble the behavior of nursery web spiders but carry their egg sacs attached to their spinnerets. There are large numbers of species of these spiders that range in body length from 1 to 2 inches. They have 8 eyes that are arranged in 3 rows. The bottom row consists of 4 small eyes; the middle has 2 very large eyes and the top consists of 2 medium-sized eyes. They depend on their excellent sight to hunt. Their sense of touch is also well developed. The abdomen is held in a raised position to keep the egg case from dragging on the ground, but they are still capable of hunting while so encumbered.

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Female Wolf Spider with Attached Egg Sac.  Image Courtesy of Muhhammad Mahdi Karim-GNU Free Documentation License.

Also unique to these creatures is the method of infant care.  Once hatched from their protective silken case, the young spiderlings climb up their mother's legs and crowd onto her abdomen.

The largest species of the wolf spiders belong to the genus Hogna. Among the Hogna species in the U.S., the nearly solid dark brown H. carolinensis is the largest species with a body that can be more than one inch long. It is sometimes confused with H. helluo which is somewhat smaller and entirely different in coloration.

Some species such as the Carolina wolf spider construct deep tubular burrows in which they remain much of the time. Others seek shelter under rocks and similar situations. They frequently change habitats, and are therefore more likely to be the ones attracted into human habitation when the weather starts to turn colder in autumn.

Daddy Longleg Spiders. Some species are also commonly called granddaddy long-legs spider, daddy long-legger, cellar spider or house spider.  These spiders are fragile with the body being 1/10 to 4/10 in length and legs which may be up to 2 inches long. They have cylindrical abdomens and their eyes are arranged in two lateral groups of three and two smaller median contiguous eyes. Other species have a small globose abdomen with eyes arranged in two groups of three and no median eyes. Pholcids are gray to brown with banding or chevron markings. 

These spiders have very long legs and look similar to the harvestmen or true daddy longlegs. The harvestmen are not true spiders and actually belong to a separate order (Phalangida). An easy way to distinguishing the two is that the true daddy longleg has a segment abdomen while the spiders do not. The members of the daddy-longlegs spiders are the most common spiders found in houses and buildings. My wife really like spiders and doesn’t want me killing these spiders that inhabit our house.  Consequently we don’t have to decorate that much for Halloween.  When it gets really bad, I sometimes sneak out with the vacuum at night. When disturbed or under threat of attack, they violently vibrate their web in attempt to discourage the intruder hence another common name of the vibrating spiders.  Some claim that this spider has toxic venom; however, their fangs are too small to penetrate the skin and are not considered dangerous. (Pat’s note: Dick doesn’t know it, but I go back out and sneak them back in after he goes to sleep.)  (Dick’s note. I do now!)

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Harvestmen. By Marcel Zurreck - Own work http://marcel.zurreck.com/opiliones/ CC BY-SA 3.0

True Daddy Longlegs or Harvestmen. These spiders spin untidy webs that are readily abandoned if they become dirty.  When webs are abandoned, the spiders immediately spin new webbing.  The result is large amount of webs that can be found in a home with relatively few spiders. The main webbing is relatively weak and typically is not used to trap prey and is primarily used for retreat.  Likewise, their chelicerae are also too small to hold prey.  This spider traps its prey by throwing tough, stiff web material over the victim. After the prey is motionless, it is wrapped and subsequently pumped it full of digestive enzymes. These spiders are capable of subduing almost any type of arthropod including larger wolf spiders, black widows and even other daddy longlegs.  Even though the average homeowner is unwilling to put up with them, these spiders are quite effective predators and can significantly reduce the presence of other bugs in the home.

In the winter when the general insect population is at its lowest, these spiders move through the house on hunting expeditions. On such occasions, they frequently start looking for the webs of other species of spiders. If found, they will vibrate the web and thus simulating captured prey. They will also act like a captured prey. This behavior includes twitching its abdomen, bouncing in place, shivering and tensing while contracting its legs toward its body.  All these behaviors tend to excite the other spiders which emerge expecting a capture prey but are consumed by the larger long-legged cellar spider.

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  Daddy-longleg or Cellar Spider. Image Dr. Kaae.

This species originally came from the tropics and in colder climates is found only inside houses. Unlike most other spiders, daddy longlegs breed throughout the year. The fertilized eggs are not found in a sac as with many other spiders, but are held in a small silk net.  Because the spider is always on the move, it is common to see a female carrying her sac of 20 to 30 eggs with her.

Brazilian Wandering Spiders. This genus of aggressive and highly venomous spiders occurs throughout most of tropical South and Central America. They belong to the family Ctenidae. The genus Phoneutria contains 8 species. The Brazilian wandering spiders can have a leg span of up to 4 to 5 inches. Their bulky body ranges from 0.7 to 1.9 inches in length.  The wandering spiders are named after their behavior of nocturnal wandering the jungle floor as opposed to residing in a lair or maintaining a web. During the day, they hide inside termite mounds, under logs and rocks and in banana plants and bromeliads.  P. nigriventer typically hide in dark, moist places in or near human dwellings.

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Brazilian Wandering Spider.  Image Courtesy of João P. Burini CC BY-SA 3.0.

This species exhibit a distinctive defensive display in which the body is lifted up into an erect position. The first two pairs of legs are lifted high revealing the conspicuous black-striped pattern on their underside while the entire animal sways from side to side. They are found in forests from Costa Rica throughout South America east of the Andes into northern Argentina and into Colombia, Venezuela, Guiana, Ecuador, Peru, Bolivia, Brazil and Paraguay. Two species (P. reidyi and P. boliviensis) are found from southern Central America to the Amazon region. The remaining species are restricted to Atlantic Forest of Argentina, Paraguay and Brazil. In Brazil, Phoneutria is only absent in the northeastern region north of Salvador, Bahia.  Phoneutria has been introduced to Chile and Uruguay.

P. nigriventer is claimed to be the most venomous species of spider. Its venom contains a potent neurotoxin (PhTx3).  It acts as a broad-spectrum calcium channel blocker that inhibits glutamate release, calcium uptake and glutamate uptake in neural synapses. At deadly concentrations, this neurotoxin causes loss of muscle control and breathing problems. This may result in paralysis and eventual asphyxiation. In addition, the venom causes intense pain and inflammation. Sensory nerve stimulation causes a release of neuropeptides such as substance P which triggers inflammation and pain.

Aside from causing intense pain, the venom of the spider can also cause priapism (prolonged erection of the penis or clitoris-several hours in some cases) in humans. Erections resulting from the bite are uncomfortable and can lead to impotence. A component of the venom (Tx2-6) is being studied for use in erectile dysfunction treatments.  The quantity of its venom required to kill a 20 g mouse reportedly is 6 μg intravenously and 134 μg subcutaneously as compared to 110 μg and 200 μg respectively for the black widow) and Sydney funnel web spider. Laboratory mice subjected to its venom experienced intense penile erections prior to death. All the above ranks this spider's venom among the most deadly found in spiders.

The Brazilian wandering spider is one of the relatively few species of spiders known to present a threat to human beings. Part of the reason why it is so dangerous is not merely a question of the toxicity of the venom, but includes its ability to deliver the venom, the quantity of venom delivered, its aggressiveness and wandering habit of the spider.  The latter makes a bite likely and increases the chance of its proximity to human habitation. Recent studies suggest that Phoneutria injects venom in approximately one-third of their bites, and only a small quantity in one-third of those cases.

As mentioned, the spider's wandering nature is another reason it is considered so dangerous. In densely populated areas, Phoneutria species usually search for cover and dark places to hide during daytime. This can result in it hiding within houses, clothes, cars, boots, boxes and log piles and thus generate accidents when people disturb it. Its other common name "banana spider" is due to its tendency to hide in banana bunches on plantations and is occasionally found as a stowaway within shipments of bananas. These spiders can also appear in banana crates sent to grocery stores and bulk food centers around the world.

Despite their reputation as the world's deadliest spiders, there are multiple studies that call in to question their capacity for fatal human poisoning.  Phoneutrias easily can be confused with other species such as the Lycosides or other large labidognatha spiders. One study suggested that only 2.3 % of bites (mainly in children) were serious enough to require antivenin. However, other studies indicated that the toxicity of Phoneutria venom was clearly more virulent than both Latrodectus and Atrax.  Many experts believe that various spiders such as Phoneutria can deliver a "dry" bite and purposely conserve their venom.  The more primitive spider like Atrax usually delivers a full load of venom. Nevertheless, there are well-attested instances of death. In one case, a single spider killed two children in São Sebastião. The spider was positively identified as a Phoneutria.

Australian Funnel-web Spider.  These spiders have fangs which point straight down and do not point towards each other. They have quite large venom glands that lie entirely within their chelicerae. Their fangs are very large and powerful and capable of penetrating fingernails and soft shoes.

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Left. Sydney Funnel-web Spiders. Courtesy Sputniktilt CC BY-SA 3.0.  Right. Courtesy Doug Beckers from Macmasters Beach, Australia. Uploaded by Jacopo Werther CC BY-SA 2.0,

These spiders make their burrows in moist, cool, hidden habitats such under rocks, rotting logs and some in rough-barked trees (occasionally yards above ground). They are frequently found in suburban locations but rarely in lawns or other open terrain.  The burrows characteristically are composed of irregular silk trip lines radiating from the entrance. Unlike some related trapdoor spiders, their burrows do not have lids.

Their primary range is the eastern coast of Australia.  In addition, some specimens have been found in other islands in the South Pacific. The only Australian locations without funnel-webs are Western Australia and the Northern Territory.

Funnel-webs are one of the three most dangerous spiders in the world and are regarded by some to be the most dangerous. Examination of bite records has implicated that wandering males cause almost all fatal funnel web bites to humans. Adult males, recognized by the modified terminal segment of the palp, will defend themselves vigorously if they feel threatened and tend to wander during the warmer months looking for receptive females for mating. They are attracted to water and hence are often found in swimming pools where they have fallen while wandering. The spiders can survive such immersion for several hours and can deliver a bite when removed from the water. They also show up in garages and yards in suburban Sydney. Contrary to a commonly held belief, no funnel-web spider is able to jump, but they can run quickly.

While some very venomous spiders may give dry bites, these spiders do so much less frequently. An inefficient mode of delivery to large animals and interrupted contact are also possible causes of low volume delivery. It has been claimed that approximately 10% to 25% of bites will produce significant toxicity, but the likelihood of this cannot be predicted and all should be treated as potentially life-threatening.

There have been 26 recorded deaths in Australia in the last 100 years from spider bites. Bites from Sydney funnel-web spiders have caused 13 deaths (seven in children). In all cases where the sex of the biting spider could be determined, it was found to be the male of the species. Most victims were young, ill or infirmed. One member of the genus Hadronyche, the northern tree funnel-web has also been claimed to have a fatal bite, but this lacks the support of a specific medical report.  Assays of venom from several Hadronyche species have shown it to be similar to Atrax venom.

The female venom was thought to be only about a sixth as potent to humans as that of the male, but recent research has proven that false. The bite of a female or juvenile may be serious; however, considerable variation occurs in venom toxicity between species.

Web Casting Spiders. These spiders have a unique means of capturing their prey.  In this case, they use a preformed web, much like a fish-net. The spider typically builds the web over an area that is frequented by insects such as a broad leaf, downed tree trunk or wall.  The net is not sticky but is quite flexible and can be expanded to five times its smallest size.  Once the spider forms the net, it moves to the desired position where it suspends on a safety line with its head facing downward and holds the four corners of the net with its four front legs.  It simultaneous holds a safety line with its last pair of legs. When a prey passes under the spider, it jumps down by cutting the safety line and simultaneous releasing the expanded tension of the net.  The net contracts and entangles the prey. Some species mark the desired target area (e.g. on a leaf below the waiting spider) with white spots.  It is thought these serve to indicate the prey is in a good location for capture. 

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Web Casting Spider with Net in Relaxed Condition.  Image Courtesy of Peter Chew, Brisbane Insects.

Mirror Spiders. One might think that these Australian spider’s mirror-like pattern may be disadvantageous as it would seem to attract potentials predators. But it is postulated by arachnologists that the opposite is probable true.  As with a disco ball constricted of different mirrors,” the reflective spots covering the spider’s abdomen most likely scatter light making it difficult for predators to see it. These small spiders in the genus Thwaitesia are commonly called “mirror or sequined spiders.  There are several other spider families include species with silvery or white shiny abdominal markings. Based on studies of other similar spiders mirror-like spots are most likely crystalline deposits comprised of guanine, a waste product produced by cells in the spiders gut cells called guanocytes.  The guanocytes cells are located immediately under the transparent abdominal exoskeleton.

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Mirror Spider. Courtesy Poyt448 Peter Woodard CC BNY-SA 3.0

SPIDER MYTHOLOGY

Because these critters are some of the larger and most commonly encountered arthropods on the planet, it follows that there are considerable myths and falsehoods associated with them. One very common belief in many parts of Central and South America is that when a spider urinates on a horse, its hoof will fall off. In such regions, children are given the task of collecting and killing all spiders around horse corrals. In actuality, horse's hooves are susceptible to splitting and even "falling off," which in extreme cases leaves the animal lame for life. This phenomenon is referred to as "founder," but is by no means due to spider pee, as spiders do not pee and in most cases their feces is quite dry. Keep in mind that one of the main physiological battles of these creatures is the loss of water and any excess water in the feces would be adding to this problem. Founder can result from any extreme tissue damage occurring on any part of the body. If this occurs, chemical messages are produced that cause the blood vessels in the hoof (and other parts of the body) to constrict, resulting in splitting of the hoof. It is possible that if a horse were to be bitten by a very toxic spider (which could cause tissue damage), founder might occur.

In some American Indian cultures, Spider Woman is a cautionary figure used by mothers to warn unruly children. Spider Woman is a protector to the Navajo. She instills a type of spiritual protection and, as a creator, a love of beauty. The comparison of an intricate and elaborate orb web to a beautiful tapestry is not hard to make. Spider Woman, being a spinner, is represented by a tiny hole found in all traditional Navaho blankets that indicates the spot where she can escape.

Gaia culture portrays the spider as a sort of earth goddess, a spinner of life and death: a positive figure. The Greco-Romans put a far darker slant to this deft weaver: known as Arachne. Athena, the Goddess of Crafts, turns her into a spider. The story goes that after a contest of skillful weaving, Athena is enraged by the subject of Arachne's tapestry--a portrayal of the gods, especially Zeus (highest god of all and Athena's father), in an unflattering light. After condemning her to hang until dead, Athena spared her life but turned her into a spider--dangling from a web instead of a noose. Arachne is the reason that spiders are known as Arachnids.

Tarantulas are hairy behemoths of the American spider world. In southern Italy, the name "tarantula" came into usage in the town of Taranto. A local large wolf spider was considered to be extremely venomous. The legend was that if this spider bit someone, they must begin dancing to a lively song known as the tarantella or they would fall into a coma. The spider became known as "tarantula." This particular spider is not really very venomous and the others we know as tarantulas usually aren't either. But their size alone is enough to give some people nightmares.

In Ancient Egypt, the spider was associated with the goddess Neith in her aspect as spinner and weaver of destiny, this link continuing later through the Babylonian Ishtar and Greek Athena.  It is the story of the weaving competition between the Greek goddess Athena and the sometimes princess Arachne. This fable was added much later to the Greek mythos when Ovid wrote the poem Metamorphoses between AD 2-8. Arachne was the daughter of a famous Tyrianpurple dyer in Hypaipa of Lydia. Due to her father's skill with cloth dying, Arachne was adept in the art of weaving. Eventually, she began to consider herself a greater weaver than the goddess Athena herself and challenged the goddess to a weaving contest to prove her skill. Athena wove the scene of her victory over Poseidon that had inspired her patronage of Athens, while Arachne wove a tapestry featuring twenty-one episodes of infidelity amongst the Gods of Olympus, which angered Athena. The goddess conceded that Arachne's weaving was flawless but she was infuriated by the mortal's pride. In a final moment of anger, Athena destroyed Arachne's tapestry and loom with her shuttle and cursed Arachne to live with extreme guilt. Out of sadness, Arachne hanged herself soon after. Taking pity on her, Athena brought her back to life as a spider (using juice of aconite) after the princess killed herself. Athena made sure that the spider retained Arachne's weaving abilities. The Greek Arachne means "spider" (αράχνη).

An Islamic tradition holds that during the Hijra, the Prophet Muhammad and his companion Abu Bakr took refuge in a cave whilst being pursued by the Quraysh. The tale goes on to say that God commanded a spider to weave a web across the opening of the cave and a dove to construct a nest in front of it, thus deterring the Quraish from entering (the Prophet's entry to the cave would have broken a web). Since then, it is held in many Muslim traditions that spiders are, if not holy, then at least to be respected.

The 10th Century Saint Conrad of Constance is sometimes represented as a bishop holding a chalice with a spider in it or over it. This refers to a story that once when he was celebrating mass a spider fell into the chalice. Spiders were believed at that time to be deadly poisonous, but Conrad nevertheless drank the wine, with the spider in it, as a token of faith.

In more recent history, the famous legend of the King Robert the Bruce of Scotland depicts a spider as a symbol for hope. Historians are unsure of the legend's truth but in the legend Bruce, when fighting the English, took refuge in a cave after a series of military failures. While hiding in the cave he saw a spider, which continued to fail to climb up its silken thread to its web. After repeatedly failing to climb upwards, the spider eventually succeeded due to perseverance. Taking this as a symbol for hope and perseverance, much like the saying "try, try and try again", Bruce came out of hiding. Bruce eventually won Scotland's independence.

The spider has been compared with vampires as they have similar characteristics. Both lure and ensnare prey before sucking the life out of their victim. Like the arachnids, vampires are believed to be able to scale walls and cliff faces, and possess fangs, similar to those of spiders.

The spider is also depicted in various urban legends. The daddy long legs (Pholcidae) were known as to have very potent venom but have very short fangs to deliver the poison. The myth might have arisen due to its similarity in appearance with the Brown recluse spider.  However, an episode in Discovery Channel's Mythbusters showed that a host was able to survive a bite from the spider. Another urban myth depicts a young woman who found out that her beehive hair was infested with Black widow spiders. An email hoax describes the attacks by the South American Blush Spider in public toilets. The alleged spider's scientific name Arachnius gluteus literally means "butt spider". It should be noted that the hoax spider shares some characteristics with the two-striped telamonia (Telamonia dimidiata).

The spider has been featured in literature for many centuries. In the Vedic philosophy of India, the spider is depicted as hiding the ultimate reality with the veils of illusion. In the epic poem Ovid's Metamorphoses written about 2millennia ago. In Chinese fantasy, Wu Cheng'en's Journey to the West, spiders came as female monsters. They tried to eat Xuánzàng, but it failed. Spiders were also depicted in Dante Alighieri's Purgatorio as the half-spider Arachne, and more recently in books such as the fantasy novel Harry Potter and the Chamber of Secrets by J. K. Rowling. This book was later followed by a motion picture of the same name, using the giant spider Aragog from the novel as a supporting character and pet of Hagrid, a grounds keeper in the book. Again in titles such as The Lord of the Rings, written by J. R. R. Tolkien, the spider takes its form as the menacing giant spider Shelob, and was featured in the film adaption of the last book of the Lord of the Rings series. Tolkien had previously used spiders in his precursor to the Lord of the Rings series with the book The Hobbit. In The Hobbit, giant spiders roamed a great forested area known as Mirkwood and attacked the main characters of the book, capturing some of them. Spiders are a recurring theme in both Tolkien's works and in other authors. The 1952 children's novel Charlotte's Web written by E. B. White, later made into a feature film in 1973 and 2006, is notable in its portrayal of the spider in a positive manner as a heroine rather than an object of fear or horror. Atlach-Nacha is the creation of Clark Ashton Smith and first appeared in his short story "The Seven Geases" (1934). Atlach-Nacha resembles a huge spider with an almost-human face. In the story,  Atlach-Nacha is the reluctant recipient of a human sacrifice given to it by the toad-god Tsathoggua.

In graphic novels, spiders are often adapted by superheroes or villains as their symbols or alter ego due to the arachnid's strengths and weaknesses. One of the most notable characters in comic book history which has taken their identity and name from the spider is the Marvel comic book hero Spider-Man. After being accidentally bitten by a radioactive spider, Peter Parker, later known as Spider-Man, was able to scale tall buildings and shoot web fluid from a box attached to his wrist. Along with these abilities came super senses and instant reflexes. The franchise, originally created by the writer Stan Lee and artist Steve Ditko, has become so popular that it has had three successful movies made based on the Spider-Man comic books. Along with Spider-Man, the comic book has also introduced several new characters using the spider as their patron: these include Spider-Woman, Spider-Girl, the Scarlet Spider, Venom, Araña, and the Tarantula. Many other comic book characters have taken the guise of a spider, including Black Spider from the Batman universe, and in mange and anime; In the Pokémon franchise, Spinarak and Ariados are similar to spiders in shape; in the Static Shockseries, Anansithe Spider takes his name and techniques from the African trickster god.

Spiders have been present for many decades in both film and television, predominantly in horror movies, which use them to cause fear, especially amongst those who suffer from arachnophobia; an acute fear of spiders. Many films have featured the spider, including: 1955'sTarantula, made in the midst of America's fear of atomic radiation, Kingdom of the Spiders, a 1977 film starring William Shatner, depicts the spiders attacking humans after their natural food supply was destroyed from pesticides; Arachnophobia, a 1990 movie in which spiders multiply in large numbers and terrorize a group of humans; and more recently, the 2002 blockbuster Eight Legged Freaks in which a group of spiders is mutated from nuclear waste and attacks the nearby town via an underground mine. Film adaptations of books featuring spiders have arisen too, including The Lord of the Rings: The Return of the King's Shelob and Harry Potter and the Chamber of Secrets' Aragog, and of comic books, including the Spider-Man trilogy. In Ingmar Bergman's film Through a Glass Darkly, the psychotic Karin believes she has an encounter with God in the form of a spider.

As the spider further embeds itself into the culture of humans, more and more depictions arise: From nicknames such as "Spider" for the Olympic skier Vladimir Sabich, to gaming depictions such as the solitaire game Spider, to team names such as the Cleveland Spiders and San Francisco Spiders to technological mentions such as the web spider, commonly known as the web crawler. The World Wide Web implies the spider-like connection of information that is accessible in the Internet. Giant spiders appear in a number of role-playing games, such as Dungeons & Dragons and the first edition of Warcraft: The Role playing Game, where they are described as "a spider of staggering size—perhaps 15 feet around—with great furred body." Atlach-Nacha is an H-game that revolves around a spider demon disguising herself as a human woman. The tarantella, a dance, is related to the spider Lycosa tarantula. As tattoos, spiders serve a visible symbolic significance in popular culture. In September 2008 a giant mechanical spider La Princesse was in Liverpool as part of a French performing arts company spectacle. In Bionicle, the Visorak horde is a species of six spider-like breeds, created by the Brotherhood of Makuta in order to take over islands. They possess mutagenic venom, and spin green, sticky webs.

Cool Spiders-Just for Fun.

https://upload.wikimedia.org/wikipedia/commons/thumb/9/91/Kaldari_Zygoballus_rufipes_female_02.jpg/1280px-Kaldari_Zygoballus_rufipes_female_02.jpgFile:David Bowie spider.jpgPhidippus audax male.jpg

Left Image CourtesyRyan Kaldari-Public Domain.                           Middle Image Courtesy Seshadri. K.S. CC BY-SA 4.0.                   Right Image Courtesy Opoterser CC BY-SA 3.0

 

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