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If you were to ask people to make a list of animals that invoke fear, it would inevitably include spiders. This fear is so well known that a unique phobia is associated with spiders: arachnophobia.

Spiders are found in all regions of the world, from the frigid mountaintops of Mount Everest to dry hot deserts of the Sahara as well as in the basements and closets of most people's homes. Worldwide, there are more than 30,000 species of these arachnids. Spiders are extremely beneficial to our environment because they consume millions of harmful insects. Almost all spiders have venom which is used to kill or paralyze their prey. Spiders will also bite in self defense or to protect their eggs as do many wild animals. Unbeknownst to many, the majority of spiders have mouth parts too small or not powerful enough to pierce human skin and most spider venom is harmless to humans.

Of all the spiders in the country probably the two most feared are the black widow (Latrodectus mactans) and the brown recluse (Loxosceles reclusa). Most people think the black widow is found only in the southern US, but its range does include WV, and it can be found throughout the Mountain State. The female can easily be recognized by her coal black color and relatively large bulbous body which is about 1/2 inch long. She also has a distinguishing red hourglass-shaped mark on the underside of her abdomen. Normally quite shy, secretive and nonaggressive, the female rarely leaves her web and will retreat when disturbed. The exception is when she is guarding her egg sack. Juveniles and males do not bite. The venom from the black widow is a potent neurotoxin affecting the nervous system and is 14 times more toxic than rattlesnake venom. Children, elderly people and people with fragile immune systems are especially sensitive to the bites from this spider.

According to James Arnold, curator of the WV Arachnid Collection at Marshall University, the brown recluse, Loxosceles reclusa, has not been found in WV; its closest occurrence has been in neighboring Kentucky. The venom from the recluse is different from the black widow's and causes necrotic lesions which can take months to heal, and there is no known antivenin. Although their range is outside the Mountain State, Arnold says there are sometimes reports of brown recluse bites in places where the spider is not endemic, but no one has produced the spider causing the incidence. The recluse is tan to yellowish brown in color and has a body that is approximately 5/8 of an inch long. It too has a distinguishing mark that can be used for identification. This mark is fiddle shaped, pointing to the rear of the spider and is located just behind its eyes. Many people have called this spider a "fiddleback."

Other spiders also have a similar mark which can make a positive identification difficult. The brown spider (L. rufescens) is in the same genus as the recluse and looks so similar to the recluse that only a trained expert can differentiate between the two. This brown spider is found throughout the world and is not known to bite people. According to Arnold, only a few specimens have been taken in Huntington. Both the black widow and brown recluse live in dark, cool undisturbed areas and with the advent of window screens and indoor plumbing, bites from these spiders are extremely rare.

As much as these spiders are feared, less than 1% of black widow bites result in deaths and, according to WV Department of Health, Epidemiology Section, there have been no known deaths due to spiders in the last few years. People desiring more information or who would like to have spiders identified, should contact Dr. Arnold, Marshall University, 304-529-0130, email warnold@marshall.edu. Just remember, spiders are very important to our ecosystem and shouldn't frighten you off your tuffet. They are simply misunderstood.

--Jim Fregonara

Editor's Note: Although the brown recluse spiders are not endemic to WV, they can enter the state through shipments of wood, especially from the South.



Uploaded: 2/21/2004
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