some kind of Faviid.
Again- nice macro.
Or is it xenia?
no. Keep guessing.Hydnophora?
Rich, the encrusting monti around that birdsnest is pretty special.
I posted a tough one: it's a Lithophyllon spp.
I like the challenge. Skeletal structures/coralites, and polyp types fascinate me.
A type of Fungiid