Looks the same as whatever is inside the fish... about the size of sesame seeds.Well i cant answer your question but what the hell is it on the base of its tailfin?
Agree with RD about the tail spot.Regarding the spots, this may be what your fish has.
Wild caught snail tank safe?
I think I found a Chinese mystery snail, in a near by pond. Given that this is an invasive species I took it home. It's in a bucket of tank water now to purge a bit. I'm wondering if there is any harm in putting in my aquarium? Any known diseases or parasites I should be worried about?www.monsterfishkeepers.com
The white lump at the base of the tail fin appears to possibly be lymphocystis. http://edis.ifas.ufl.edu/fa181