Blue coral (
Heliopora coerulea) is a species of colonial
coral and the only species in the family Helioporidae and the only
Octocoral known to produce a massive skeleton. This skeleton is formed of
aragonite, similar to that of
scleractinia. Individual
polyps live in tubes within the skeleton and are connected by a thin layer of tissue over the outside of the skeleton. It was described by Pallas in 1766.