Of the 45,000 species of spiders known globally, an estimated 600 live in South Carolina. In the Lowcountry, these mid-summer days are when our eight-legged neighbors become busiest as spiderlings that emerged in the spring have reached full maturity, motionless and waiting for prey in their elaborate webs. Fortunately for us, there are only four venomous spiders in our area - three varieties of the hourglass-marked widow family, and the brown recluse - all of which will only bite if physically threatened. The widows' bites, if painful, are very rarely fatal; the brown recluse's bite, however, can in severe cases cause swellings on the skin that can take months to heal.
Fortunately for us, the most commonly encountered Lowcountry spiders are non-venomous. Often popularly grouped together as banana spiders, we share the environment with three distinct types of yellow/black spiders - the yellow garden spider (Argiope aurantia), the golden silk orb weaver (Trichonephila calvipes), and a newcomer, the Joro spider (Trichonephila clavata). If you encounter any of these three types, you will most commonly be looking at the imposingly large female, while the much smaller males may be nearby in their own webs to entice the female by strumming on hers with their legs. And, yes, the female may sometimes consume the male after mating before laying her eggs; in any event, an unconsumed male will die shortly after mating.
You can tell you're looking at a yellow garden spider if its web, usually constructed in sunny, open areas, has a characteristic zig-zagged thread, the stabilimentum, through the middle of the otherwise round web (seen in the photo at the top of this post). Its purpose is uncertain. The webs of orb weaver spiders, found in dense vegetation, are to many admirers the most beautiful with their yellow/gold coloring, which may be intended as camouflage in the shifting sunlight and shadows of wooded areas. The orb weaver is also the largest of the three types, with females' bodies as large as two inches. The newcomer to the Lowcountry, the Joro spider, arrived here from Asia, where it's common in China, the Korean peninsula and Japan. It's also an orb weaver with a bright yellow-and-green striped abdomen and darker stripes on its underside. As a relatively new non-native species, its effects on the southeast's ecology are still under study.
Whatever your reaction on seeing one of these arachnids, remember that spiders are important to ecosystems as a natural form of pest control, capturing and consuming insects that are harmful to crops, pets and us. And few sights are more beautiful than a delicate golden web glistening in the summer sun.
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