Saint Andrew's Cross Spider

Description:

Argiope aemula (Walckenaer, 1841) is well described in Wikipedia as follows: The female is larger than male - often reaching 25-30 mm while the male tends to stop growing at 5-8 mm. Its Cephalothorax is brownish with a white pubescence. Its posterior median eyes are encircled in black and its sternum is heart shaped. Further, there is a narrow elongation found at the distal end of sternum. Its oval shaped and anteriorly truncated abdomen is yellowish with black stripes. Its ventrum is brownish with yellow parallel lines. Argiope aemula has silver hairs on its carapace - hence its namesake. The female spider has a carapace that is flat with yellow and black horizontal lines that are present from the end of the carapace to the entirety of the backside. The spider has eight legs that are doubled up and spread like an X in the web. The legs are long with claw like structures at the end. Their legs have grey color and black rings around them. The cephalothorax is a dirty white color and the sternum is shaped like a heart.[5] There are four yellow dots that are placed in its abdomen and are organized vertically. The females’ exotic color has been speculated to be associated with prey attraction. Males are much less brilliant in their color. Their sternum and backside are brownish while their carapace is black. Both sexes have abdomens that are oval shaped. They are easy to identify thanks to their stabilimentum in their web. Males are 5-8 mm while females are 23-30 mm creating a large size dichotomy. Wikipedia

Habitat:

I spotted this beautiful female A. aemula on foliage in the corner of our front yard. I had previously seen many specimens of this species, in the rice fields, but the proximity of this one gave me a greater opportunity to observe it, pretty much any time. So I set about taking pictures of it from time to time and even took some video footage of it wrapping its prey. However, I was not as observant as I thought because about three weeks after I first spotted this spider, I suddenly noticed (just to the right of the web) two egg sacks. The upper one was spilling out hundreds of tiny spiderlings. To this day I can't understand how I could have been so careless. I almost missed the entire event. This was a valuable lesson - look at the entire surroundings, not just the specimen !

Notes:

This species of Argiope exhibits at least three defensive reactions: 1. If startled, it will drop to the ground and quickly hide in the undergrowth. 2. It sometimes quickly retreats to the edge of its web and stands guard to observe the threat. 3. It grabs hold of its web with all eight legs and ferociously carries out a rapid and lengthy series of "push-ups" which cause the web to oscillate back and forth (2 to 3 inch oscillation). I don't know how successful this ploy is in deterring potential predators (if that is its purpose), but it surely scared me. I have never put my hand near one since that time, even in the knowledge that it is considered harmless to humans. The whole oscillation thing just looks demonic.