This large, attractive spider is found in dry habitats from southern California to Florida, and to the south as far as Argentina.   It is a close relative of the banded argiope and the golden garden spider.   In California, the silver argiope is found mainly along the southern coast in Orange and San Diego counties, and is most often seen in clumps of prickly pear cactus.   Several individuals may inhabit one cactus clump.   The most visible are the large females (shown here); as with many spider species, males are much smaller and less conspicuous.   I took some of these photos on an annoyingly breezy day in late summer in Crystal Cove State Park in Orange County.  There was just enough wind to shake the webs almost constantly, making sharp macro images a real challenge.   The spider at upper right is in a rigid 'alarm' posture, which she assumed after I accidentally tugged her web.   The photos below were shot in the Bolsa Chica wetlands reserve, also in Orange County.