Spiders are usually associated with our fear of creepy, crawly things. There have been many books written, movies produced, and songs recorded about spiders, usually in a way that builds upon our fear of them. Some people fear them based on their look, size or bite while others fear them in general. Spider distribution can continuously change and they can, on occasion, be found outside of their documented location by being relocated through humans via transportation vehicles, luggage , or other personal belongings. There are over 35,000 described species of spiders worldwide but most are no threat to humans. There are three dangerous spiders commonly found in South Carolina.
Black Widow Spider (Southern and Northern)
Black widow spiders get their name from the popular belief that the female eats the male after mating, an occurrence which rarely happens in nature. This spider has a worldwide distribution with at least 5 species found in the United States and specifically, South Carolina. although their color can vary, the black widow can be identified by its black abdomen with 2 reddish triangular markings usually joined to form a reddish hourglass-shaped mark. Several varieties make up the black widow family so identification and control is better left to pest control experts.
Black widow egg sacs can be constructed in 1-3 hours and, depending on the species, each female can produce 6 to 21 of these sacs with an average of 185-464 eggs per sac. Black widow spiders spin an irregular web and hang from it inverted or upside-down. They create their web mostly at night and use it to capture their prey.
As far as toxic bites, only the female is of concern. The male’s poison/venom sacs cease development and he does not attack prey upon maturity. It’s interesting to note that spiderlings are poisonous when ingested until they are 18 days old and then lose their toxicity. The black widows venom is a neurotoxin and the female will aggressively attack immediately after laying her eggs and while guarding them.
Although a black widow bite is not always felt it can be detected by slight local swelling with 2 tiny red spots where the fangs entered. Usually, pain is almost immediate and reaches its maximum in 1-3 hours, continues for 12-48 hours, and then gradually subsides. The major symptoms include increased body temperature and blood pressure, profuse sweating, and nausea. There is an anti venom available and, when treated, bites are rarely fatal except occasionally in small children.
Brown Widow Spider
Brown widows are similar to black widows but they tend to be brown or grayish-brown in color. They may have 3 white spots on top of their abdomen, a median white band on the rear, 4 diagonal white bands on either side, and a yellow to orange hourglass mark on their underside.
Brown Recluse Spider
Brown recluse spiders get their name from their coloration and reclusive habits. They are mostly found throughout the south central Midwest and southward and sometimes just outside of these areas. Their are at least 11 species that are recognized, with 6 of them being of public health importance. These spiders are tan to dark brown in color, usually with a darker fiddle-shaped marking on top of their abdomen. They are the most miss-identified spider in South Carolina. They are rarely found in this area.
The female will produce 1 to 5 egg sacs with each one containing 31-300 eggs. She will spin a web in an undisturbed area and will use it mostly as a retreat, not to capture prey. Both the male and female spiders can inject venom and should be considered dangerous to humans. This venom can produce necrosis or dead tissue, resulting in an ulcerating type of sore. Typically, the bite is not felt but may produce an immediate stinging sensation followed by intense pain. However, it can take as many as 6-8 hours for this reaction to occur. A small blister usually appears and the surrounding bite area becomes swollen. Symptoms include restlessness, fever, and difficulty sleeping. The dead tissue gradually drops off during the next 10-14 days, leaving an open ulcer and possibly exposing the underlying muscles and/or bone. Healing is very slow and usually takes several weeks, resulting in scar tissue.
Brown recluse spiders are typically found around rocks, piles of inner tubes, utility boxes, woodpiles, under bark, etc. They have been found in such places as outside rodent bait stations and infesting cedar shake roofs. In your home, they can be found in almost any undisturbed area to which they can gain access. They are most commonly found in boxes, among papers, and in seldom-used clothing and shoes. Storage areas such as closets, bedrooms, attics, crawl spaces, and basements are the areas of greatest occurrence. They will typically run for cover when disturbed. Bites have been reported to occur when putting on seldom-worn clothing or shoes, when cleaning out storage areas, or by rolling on the spider while in bed. They can also be found in commercial buildings that have heat tunnels, boiler rooms, attics, basements, storerooms, and garages. Its worth noting that it is impossible to identify a spider bite from the bite alone.