Not so itsy bitsy

I wish I had taken these photos in late October.  I was just a little late for Halloween!

 

I'll also admit that I'm a little squeamish around large spiders.  [This individual was ~2 cm (3/4 inch) long.]  But if I can watch them from a distance, I'm intrigued by their variety of shapes and sizes, color patterns and life histories.

This species is quite visible right now in low grassy areas on Bodega Head.  It creates a large orb web and tends to sit in the center or near the top edge. 

Some have very large, swollen orange abdomens (see next two photos). 

 

 

On the dorsal (upper) surface, there are noticeable white spots, some with pupil-like markings similar to cats' eyes.

 

Below, there is a beautiful combination of burnished orange bordering iridescent metallic purple.  (I'd like a sweater with those colors!)

 

In the photo above, note the spinnerets (silk-spinning structures) at the tip of the abdomen.  They are black with a yellow ring at the base and are arranged in a tight circle.

This might seem crazy, but they reminded me of sea urchin teeth!  Urchins have five pointed teeth that come together for grazing on algae (see below).  Drawing parallels between spider spinnerets and sea urchin teeth — see what happens when you spend time in both terrestrial and marine environments!

 

(This urchin skeleton, missing most of its spines, washed up on the beach in January 2009.)

Back to the spider...I tried to figure out which species it is, but so far I haven't had much luck.  I'm wondering if it's in the genus Araneus, but if anyone out there can help with an identification, I'd be grateful!