Red corals are long-lived animals, reaching over 100 years of age! The red coral o precious coral is an invertebrate, colonial animal (Cnidaria-Anthozoa-Octocorallia), mainly produced by the accumulation of calcareous encrusting algae growing in dim light conditions.
It is endemic of the Mediterranean Sea. It is characterized by an intensely coloured red skeleton, which is used for making jewellery. Its intensive fishing is, without doubt, the main threat to this species. Although this activity is strictly regulated, illegal fishing is an important problem.
The red coral grows very slowly, usually less than one millimetre in thickness each 4 years. Along the Costa Brava, for example, it can be observed all year round from 3 meters depth downwards, in small caves, overhangs and in fissures or cracks in the rocks.