Eight-ray Fingercoral

About

The eight-ray fingercoral (Madracis formosa) is a Caribbean SPS coral recognized by a combination of traits that set it apart from similar columnar species. Its colonies grow as upright, club-shaped pillars that occasionally branch and show a slight flattening in cross-section. What really distinguishes it from other Madracis species is the consistent presence of exactly eight primary septa radiating from each corallite, giving each polyp a neat, symmetrical appearance. The corallites themselves sit well apart from one another on a finely textured coenosteum covered in small spinules, and each has a solid conical columella at the center. Coloration tends toward green with contrasting yellow oral discs, which gives the colony a two-toned look when polyps are extended. In the wild this coral lives on lower reef slopes sheltered from heavy wave action across the Caribbean, ranging from fairly shallow depths down to nearly 100 meters. In the aquarium it demands the kind of care you would expect from an intermediate-level SPS coral: robust water movement and intense lighting are both non-negotiable. It is reef safe and poses no threat to neighboring corals, but its needs make it a better fit for a well-established system than a beginner setup.