This is a parasite Cerathotoa Italica that eats away the tongue and then leeches on everything this fish eats.http://plazilla.com/page/4295024237/parasieten-die-zich-voeden-met-vissentongen (in dutch)
The Blue Ribbon Eel
Sand grains from Maui, Hawaii Magnified 125x
Kole tangs always have that bright yellow ring around their eyes, but usually start out with dull brown bodies as juveniles. It's not until they're about six months old that they turn orange and their blue spots and stripes begin to come out.