Carolyn Stables (PAS Member) found this in her garden:
More Information on the Spider:
Species Argiope argentata – Silver Argiope
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Class Arachnida (Arachnids)
Order Araneae (Spiders)
Infraorder Araneomorphae (True Spiders)
No Taxon (Entelegynes )
Family Araneidae (Orb Weavers)
Species argentata (Silver Argiope)
Other Common Names
Silver Garden Orbweaver
Explanation of Names
argentata = silvery
females average 12 mm, males average 4 mm.
Posterior half of the top side of the abdomen is dark-colored with “windows” of white. The division between the light-colored front half and the dark-colored back half is usually straight and unbroken.
These orbweavers place a conspicuous zigzagging white silk banner in their webs called the “stabilimentum” which can be used to identify the species. In this species four stabilimenta form a cross in the web of mature spiders. Juveniles of many species, including this one, spin a spiralling stabilimentum from the center of the web. The function of the stabilimentum is not fully understood. Hypotheses are; that it stabilizes the web, or makes it more apparent to birds which will thus not fly into and wreck it, or it reflects light to attract insect prey, or perhaps most likely helps to camouflage the spider in the web.