Backyard beauty of a spider

Silver Argiope (orb weaver spider)

Silver Argiope (orb weaver spider)

This weekend I stumbled upon a terrific spider in my backyard.  It’s its web that caught my eye first, as it had a distinctive zig-zag pattern like this:

Illustration by Erin Hunter. www.baynature.org

Illustration by Erin Hunter. http://www.baynature.org

Turns out with a little sleuthing, I found out that it’s a Silver Argiope or Argiope argentata a type of orb weaver spider. 

According to a site on the UC Irvine website, it is common in Southern California in the Fall and those zig-zaggy features are called ”stabilimenta” in the orb web, asserting that they “probably … make it more visible to birds who might otherwise fly into it accidentally and destroy [the web].”  Perhaps it also creates a bright spot that would attract insects like moths.

On closer inspection, there were in fact TWO spiders on the web. One very big and one very small, so a female and male!!! Take a look at this fantastic photo.  It shows the two of them sharing the same web, one on either side.  I believe the male is gingerly courting the female … gingerly because it might be that the female eats the male after you-know-what like with black widow. 

Female & Male together on her web

Female & Male together on her web

Upon zooming into this photo, I noticed that indeed the male had enlarged pedipalps used in mating for transfer to the female. This feature is unique to spiders, according to Wikipedia. 

The following day, she was no where to be seen although he was there (not eaten – whew). Perhaps she was laying eggs – her final act just like Charlotte’s Web.