Montipora flabellata

Montipora flabellata, the Blue rice coral, is a species of coral in the family Acroporidae.
Description.
Common in shallow water exposed to surge. Usually blue (which may photograph pink), also brown or purple. Colonies are encrusting, with irregular lobes.
Ecology.
Like many corals, Montipora flabellata has a mutually beneficial relationship with zooxanthellae, which are photosynthetic algae that live within the coral's tissues.