Argiope aurantia

During late summer, staff and visitors at Prairie Ridge Ecostation have been treated to colorful discoveries of the arachnid variety.  One of our most ostentatious spiders is the Black and Yellow Garden Spider Argiope aurantia.  Many folks that live in the Carolinas are familiar with the large black and yellow females which can grow up to 3-inches in diameter. The male is much smaller and is often found in a smaller web adjacent to the female's web.
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These diurnal spiders are often identified from a distance by their large circular, or orb webs.  A special characteristic of this web is a dense zigzag pattern of white silk in the center of the web.  This pattern of silk is known as the stabilimenta.  The function of the stabilimenta is not fully understood but possibilities include camouflage for the resting spider, a lure for attracting insects, or a warning to birds and other large animals to prevent them from accidentally destroying the web.  The stabilimenta's resemblance to writing is credited with the spider's common name "writing spider."

Be sure to look for the large webs of these colorful spiders in your backyard, or during your next visit to Prairie Ridge.