Thank you so much Ms. Howe and GB Edwards for taking the time to do this!!! I feel quite honored to have posted the first photo of a female of this species. I had absolutely no clue what she was, once again thank you for identifying her. Incidentally she is still with me right now as the weather has been rather unstable recently, (I prefer to release my temporary captives in the best possible weather.) she's very non aggressive and eats well off of tweezers.
Be Well and God Bless
P.S.
How big will she get?

I have wanted to see what a female looks like for a long time, thanks for posting these! And I'm happy she's in good hands!
She's actually full-grown right now, so she won't get any bigger. The only part of her that can still change is the size of her abdomen. It will expand if she eats a lot (or is pregnant), or shrink if she's dehydrated or starved. We can tell she's fully mature from your 3rd image of her underside. See the two bright white circles? Those are her lung covers. Then right in between those is a sort of reddish region; that is her epigynum. Only adult females have one. It's functional genitalia. In younger females, they don't have anything in that spot yet.
So actually, if you keep her for a while, there's a chance she might make an egg sac. Since she's sexually mature, she might have already mated before you found her. Feeding her regularly will prompt her to start growing the eggs. In nature, I think this species probably lays their eggs inside a rolled up leaf.

Such wonderful info! I knew about the lungs and epigynum but I had no idea that it was actually non-existent in immature females. That makes perfect sense and will tell me alot about the status of of my spiders from now on. Thank you! Question, I would love for her to make an egg sack if she's pregnant but I would like her to do so on my plants so that they could hatch there. Does this species roam around alot or is she likely to make a home in my container garden? I was thinking I could pump her up with lots of food and then place her there so she wouldn't need to hunt for awhile. Do you think she'd stay?
Be Well and God Bless

This species is a hunting spider, so it will wander around looking for food at night (as opposed to staying in a web like some spiders do). I really don't know whether she would stay in your garden or not. I don't have any personal experience with this species... but in the scientific papers on it, some researchers note that they've been found in different types of trees. So I don't know if it likes to be further off the ground, or if it was just a coincidence that they were found in trees. I bet she'd stay anywhere as long as food and a little moisture was available.

Thanks again Ms. Howe, can I call you Mandy? I'll just put her on my plants and see what happens! I have noticed that many times when I put spiders of various types in my garden, I tend to see them there again. Maybe she'll stay, maybe she won't, it's up to her. At least she'll be well fed first. :)

A note on her behavior; she's VERY nocturnal, just like you said. Nihzoni will move around a little during the day, but she won't eat anything until it's totally dark. The next morning I find her food item in shreds!!! I wish I could see her in action...

Come to think of it, she may in fact have come from a tree... The day I found her there had been a bad storm and I was bringing some of my plants inside for some tending. But I also brought in a fallen tree branch that I intend to make use of and sat it on the floor next to said plants. Now here's the thing, I checked that branch really well for critters before bringing it inside... or so I thought. Perhaps it's more likely that she had been hiding under the bark, and then crawled out and onto one of my plant pots because of the disturbance?
Incidentally, the tree was a Scrub Oak.

Come to think of it, would it be in her best interest to put her in a tree instead of in my garden?

Be Well and God Bless

You're welcome. Yep, you can definitely call me Mandy. :-)

Nihzoni: pretty name! Sure, it's possible she could have been under the tree bark. I don't know what the weather is like in Florida right now, but a lot of spiders here in the Pacific Northwest are still overwintering under tree bark and stuff. I collect the majority of my spiders from fire wood when I go out to chop it. They hang out in between the logs and under the loosened bark. The nocturnal wandering-hunter spiders (like yours) will still hide in that kind of spot during the daytime, too, no matter what time of year.

I think you could put her anywhere you want... maybe wait until it's dark, or nearly so, so that she has some time to find a good spot, without predators (like birds) looming overhead. That Scrub Oak sounds like a good spot, actually. She'll just keep exploring each night until she finds the place she likes. :-)

Thanks Mandy, that sounds like a good idea.
Be Well and God Bless

Once again, thank you for all your help Ms. Schimming. I look foward to figuring out more mysteries together!
Be Well and God Bless