I am not sure if this is in the fungus family or lichens or what. This was what appeared to be a growth 80-90 cm across the widest part. The center was white there was a light green band close to the edge with the edge being white.
This was spotted on a tree in the Amazon rainforest of SE Ecuador. I don't know trees so cannot tell you what kind of tree. It was made of wood :-)
As I said, this may not even be something that should be posted. If not, please let me know and I will remove it. Fungi and lichens sound interesting and we are surrounded by rotting trees here so I should be able to get out and get some good photos.