Hello,
The black is scabbing and scar tissue. I suspect while free she was too dry and had a bad shed that she pulled off on her own.
I have 4 Tokay rooms that are hot and 'dripping wet' humid and include open fish tanks w/ Tokay friendly egress and misters for the open area and tropical plants. These rooms have free roaming Tokay for cricket clean-up. Once in a while one will get out into the rest of the basement which is cooler and much dryer and more comfortable for the pups & humans. Some of these guys can be out for months but once I catch them again, they usually have indications of dry sheds and need a good soaking to revive their skin. Home heating/AC systems are designed to remove the humidity from the air. Dry air is much more comfortable to us, but not so good on Tokay skin.
(I actually cut a Tokay Portal to allow these guys back into a snake room. This room is a bit warmer and more humid than the basement but not like the Tokay rooms. There is no full-time resident Tokay in the snake room because there are no escaped crickets. I do have to cover the pinkie bins, HA! I set up another Tokay 'fish tank' and a couple of easy-to-get-to vertical hides, and sure enough, they find their way in eventually.)
As noted before, check her feet just after the next couple of sheds to see if there is anything stuck to the scar areas. You most likely will not find anything if your enclose is up to Tokay humidity and misting levels.
