distinguishing black ocellaris and black percula..not the same??

[Kabong]

There is only a black ocellaris
It's called a black perc quiet often though and sometimes a Darwin clown.
Darwin because the only place in the world they are found in the wild is Darwin Australia.

When I got mine he looked like the "Juvenile"
He darkened as he grew to the point where he looked like the adult.
I'd say he probably stayed like that for at least 6 months before the orange darkened to the point where he looks like the bottom one.

However, I don't believe all will darken some may retain their colored face.