I have confirmed under a microscope that this species is indeed Peckharmia, according to the Spiders of North America ID manual. It has every required character. With Mandy's assistance, we have it as Peckhamia americana.

Moved from Jumping Spiders.

From the newly uploaded epigyne shot, I believe this is P. americana. Thank you Mandy for pointing me to the right resources.

I found this hitchhiker on the spider after the spider died. The hitchhiker was still alive and well.

Moved from ID Request.

I didn't know this genus well right off hand, but I did some research on what distinguishes each of our four species from each other and found:

-Can't be P. seminola because those do not have the constricted abdomen.

-Can't be P. picata because those have a conspicuous constriction right behind their rear eyes (the posterior laterals). They also have a pair of white dots between the rear eyes and another pair on the sides of the abdominal constriction.

-Can't be P. scorpionia because the first tibiae don't appear enlarged enough. Also, in this species the eyes do not form a line as wide as the carapace.

So, if I read everything correctly and interpreted it right, this neat gal should be Peckhamia americana by process of elimination. So, if you get her under the scope, the epigyne should look something like this fig. 4 if she is indeed an adult.

We don't have many Peckhamia in the guide, so this is a nice contribution! You'll have to update us on what the scope yields. I can already see in your last venter image that the epigyne does look a lot like the diagram I gave a link to.

I forgot to mention that this spider is only using it's posterior six legs for walking, keeping legs I tucked as shown. Corinnids at least wave that first pair like antennae, but this spider looks so much like an ant that maybe it doesn't have to.