Leopard print pattern on my dog’s wiener - please tell me it’s not ringworm

Just noticed a red leopard print pattern on my dogs wiener. Doesn’t appear to be on the rest of his belly, and I can’t tell if it’s on his skin because he’s double coated.

It doesn’t seem to be bothering him much, but he’s normally a wiener licker so it’s hard to tell what’s out of the ordinary for him.

He’s also been scooting quite a bit - we live in a high mosquito area and he has definitely gotten bites in/on his very exposed butthole.

Vet appt is Friday but want to rule out ringworm to know how much cleaning I need to do.