Cladocora caespitosa, commonly known as Coral loaf or “cushion coral”, is a stony coral of the subclass Hexacorallia, phylum Cnidarian. This species forms the only true coral reef in the Mediterranean Sea.
The polyps are a clear maroon colour, around 5 mm in diameter and form cushion-shaped colonies, in symbiosis with Zooxanthella algae. They produce deposits of calcium carbonate which form the calciate structures in which they live. It is the largest stony coral in the Mediterranean, reaching up to 50 cm in diameter. C. caespitosas have an average generation length of about 30 years.
Distribution and habitat
This species is endemic to the Mediterranean Sea, where it is attested already in the Upper Pliocene. It is common on rocky seabeds between a few metres and 60 metres in depth. In the marine lagoon of Veliko Jezero, in the marine reserve of Mljet island, Croatia, there is a small coral reef made up of C. caespitosa. This is the only true coral reef in the Mediterranean.
The colonies grow through budding, but the species spreads through the settlement of plankton-like larva on seabed suited to colonisation.