Need help ID.....

[hfp75]

I have a rabbit fish that has that appears to have two small rings 1/8"EA by its Pectoral Fin. It looks more like a figure 8, I dont know what this is I'll try to snap a picture of it...

Any ideas? what causes a ring(s) to form on a fishes skin?

These just showed up last week and the fish seems normal....