These are soft octocoral that are endemic to the Mediterranean. The beautiful deep red colour is retained even after the animal is removed from the water and dried. It is much valued in the manufacture of jewellery, and the resulting unsustainable levels of harvesting have depleted this species in many areas. The powdered endoskeleton is also used by some practitioners of alternative medicine.
Red coral tends to be found at depths from 20m to as deep as 300m and grows on hard substrates, with a preference for dark environments with minimal sedimentation. At shallower depths it is often found in caves, overhangs and crevices. Red coral forms irregularly shaped branching colonies. The calcium carbonate endoskeleton can reach a length of 60cm if left undisturbed.
The white polyps seen along the branches are the soft part of the animal, extended to feed, each one with the characteristic 8 tiny tentacles or rays of the octocoral. The branches are covered with a bright red tissue, though occasionally these are white or even yellow. The inner limestone skeleton also contains carotene, resulting in the various shades of red that jewelers find so valuable.