Aphonopelma seemanni [ventral sexing]

the ventral is a bit dark, but it looks male

The door looking or capital upside-down U area between the first pair of book lungs does seem to suggest it's a male.

@LailaQ Ahh and I see we've had a little stroll happen. Man, if my female ever got out in my room, it would be a complete and utter nightmare. Thank goodness you found him.

@Androxian LOL. Indeed. It was a surprise to not see him this morning, chilling in his usual spot. I went through his tank with a fine-toothed comb, and nope, he had done a vamoose. I had to deal with my kids and breakfast and getting them to school and all that—before I could start searching for the missing spider. Long story short, my youngest cat helped me (under my watchful eye!!!), like I was hoping he would do. No joke, he lay down facing the spot where the tarantula was hiding, in the closet, under a baby gate, in a dark area where I otherwise wouldn’t have seen him for a looooong time. Mr. Tarantula also wasn’t too happy to be caught and put into his (new) home. But this one’s got latches, so I’ll be able to sleep better tonight.