What is this?

[Bogertophis]

Not to cause any alarm, and by no means am I a vet, but this looks similar to a minor fungal infection in humans. For some reason these infections in humans are usually round or rounded in shape and have brighter red irritation around the edge of them.

Now I'm not even sure if this is possible in snakes, but the resemblance was so close I figured I'd bring that up and see if anyone knows any more about fungal infections in snakes?

I actually have seen a fungal infection on a BP but it looked nothing like this; but that in NO way rules it out...IMO. The only type of fungal infection I've seen was
on a BP & it was the type where individual scales got dry & shriveled-up looking; it responded to the topical anti-fungal that was prescribed for it. But I do know what
you're talking about (in humans, tinea versicolor or tinea corporis) & I'm not sure if this could be that or not?

I would say that a vet check is in order IF this doesn't seem to improve with topical antiseptic treatment. Also, I think it looks worse just because it's
on a white snake.