Coral reefs are one of the world’s most important ecosystems, sheltering and sustaining about a quarter of all ocean species.

The reefs are formed over thousands of years, mainly by colonies of animals called polyps. These creatures make stony corals, the foundation for most coral reefs, by secreting protective skeletons of limestone. As these skeletons accumulate over time — with new colonies of polyps growing on top of the skeletons of older ones — they build up the base of coral reefs.

The Coral Reefs stamps feature highly stylized digital portraits that depict four types of stony corals and associated reef fish:
•    Elkhorn coral and two French angelfish
•    Brain coral and a spotted moray eel
•    Staghorn coral and bluestriped grunts
•    Pillar coral and a coney grouper and neon gobies

The pillar coral grows vertically in a column-like fashion from an encrusted base. There is no secondary branching. It may reach heights of 3m and 10cm in width. During the day, unlike most coral species, the polys are visible making the skeleton of the coral impossible to see. Its many tentacles from the polys gives it its furry appearance. It is grey-brown or olive in color.
 
It is found in the western Atlantic Ocean, surrounding most of the Caribbean islands, and the southern Gulf of Mexico, in addition to being on the coast of Florida and Bahamas. It was once found in Panama until it was eliminated there,mand is a native species to Trinidad and Tobago.

They are marine species, typically found on a flat or slightly inclined reef (back-reef or fore-reef) environment. They can survive an upper depth imit of 1m and a lower depth limit of 25m, but are commonly found at depths of 5-15m.They are not found in extremely exposed locations, but are resistant to heavy wave surges. Unlike most hard corals, they feed during the day (diurnal activity).

Pillar coral is azooxanthellate species. This means that the coral acquires most (about 90%) of its energy through the symbiotic relationship it has with algae called zooxanthellae. The algae are found within the tissues of the coral, where it provides the building blocks, such as amino acids, glucose, and oxygen to the coral, which are then used to synthesize proteins, carbohydrates, and other necessary substances. The remaining energy requirement is obtained from the coral polyps using its tentacles to capture plankton, which are ingested through the mouths of the polyps and digested.