Phyllomedusa azurea - Brown Spot Appeared and Raised Lump

[MantellaGuy]

Hi all,

My partner noticed today that one of her Phyllomedusa azurea individuals has a raised bump appear on it's forearm, adjacent elbow, which has also got a small brown spot too. Here are a few photos of it, unfortunately, it's just a mobile picture but should be able to get clearer ones later.





Unfortunately, I am stumped with this as I haven't personally seen anything like it before, so I am asking all you kind folks for some help, which would be muchly appreciated.

I looked this up in several books and also online and found no illness resembling such a thing, any ideas?

Many thanks in advance!

Josh