Some kind of jumping spider, I guess. They found my backpack on a sandy bank of the Potomac River.
Thanks! I know very little about spiders. This one was in the same area, and was definitely hopping around. It's camouflage is nearly perfect, making identification a challenge. I was thinking they might be the same species, but really have no idea.
@Yasha
Agreed, and like Iris DeMent sang, so beautifully "I think I'll just let the mystery be."
https://www.youtube.com/watch?v=nlaoR5m4L80