Cushion Coral

Overview

Cladocora caespitosa, commonly known as the cushion coral, is a stony coral endemic to the Mediterranean Sea. It is a significant bioengineering species, recognized as the only coral in the region capable of forming true reef-like structures.

Distribution & habitat

This species is found throughout the Mediterranean Basin and in adjacent areas of the Atlantic, such as the coasts of Portugal and Morocco. It typically inhabits rocky seabeds and seagrass meadows, thriving at depths ranging from a few meters down to 60 meters.

Appearance

Cushion coral forms hemispherical, brownish colonies that can exceed 50 cm in diameter. The colony structure consists of numerous individual, tube-like polyps (corallites) that are roughly 4–5 mm in diameter. These polyps are tightly packed together, giving the colony its characteristic cushion-like or bushy appearance.

Biology & behavior

This coral lives in symbiosis with zooxanthellae, which are unicellular algae that provide nutrients through photosynthesis. The species is known for its longevity and slow growth rate. It also exhibits a unique survival mechanism called rejuvenescence, which allows it to recover following environmental stress. Due to its sensitivity to rising sea temperatures and mass mortality events, it is currently classified as an endangered species.

Feeding

Colonies obtain nutrition through two primary methods: capturing plankton with their polyps and utilizing the nutrients synthesized by their symbiotic zooxanthellae.