Insect and Spider Identification: Beautiful spider, 1 by KroniKles

KroniKles wrote:
I found this cool looking little guy outside my back door, Its been making his big web there the past few nights and I'm starting to wonder what kind of spider it is out of curiosity. It has this very distinctive marking on the underside of his back end and some black or maybe brown stripes on its legs i can see from his underside. I would say hes about the size of a half dollar coin, i guess about an inch from front to back.

Here are some nice high resolution pictures of the top and bottom view with the marking:
http://img401.imageshack.us/img401/4138/img0330c.jpg
http://img27.imageshack.us/img27/8626/img0327cg.jpg


Thanks in advance anyone that could help! :]