This spider is a good 1.5 - 2 inches in length, and yes, those look like warts on its back in real-life too. It was on the driveway when I took the dog out for her late-night rounds, so I grabbed my camera and snapped a few shots - but the lighting is poor.
This is a wolf spider (family Lycosidae). Those things that look like warts-- are spiders. They are the newly hatched young that cling to the back of the adult.
Yeah, I realize that after I posted it and then I zoomed in on it even more :-) I hadn't realized how big a wolf spider could get...
