My daughter got this Iguana 3 weeks ago from a pet store. He's not very social, but shes patiently working on that. The little guy has recently developed a black spot on the side of his head/neck/dewlap that seems to be slowly growing. We're going to take him to the vet for a checkup in a few days, but I am concerned about this spot. He has a good setup, a large wire cage with a UV and basking light, its not burns because we have them hanging over the cage and he cant get to them. He did have a few mites, but we used spray and cleared them up shortly after we got him. Hes on a 12 / 12 cycle, he eats well, and poop looks good. He is pretty stressed in this photo because we just took him out of the bath. We were hoping a good soak in warm water would help clear it up, but it did not. Here is a picture of it. Any help would be appreciated, thanks!