Hi. One of your wolf spiders. Hogna from the looks of it.
Genus Hogna – BugGuide.Net
Comparing with last one, this one seemed to have thinner legs, and it used the a standing up tactic showing its black downside. Also the pattern on it back is more detailed. Thank you.
Thinner legs may be a male and rearing is a defense posture. Not a good time to put a finger in its face. Completely black bottom with som light on the legs, it could be Hogna carolinensis.