Long Spine Urchin
Diadema antillarum
| Identification | Black body with extremely long (up to 12 inches), slender, needle-like venomous spines. A distinctive red-orange ring (the anal cone) is visible on top. Juvenile form has banded black and white spines. |
|---|---|
| Maximum Length | 4 inches body; spines to 12 inches |
| Origin | Caribbean, Atlantic |
| Minimum Tank Size | 75 gallons |
| Reef Compatibility | Reef safe with caution — requires space |
Behavior
Among the most effective algae controllers on Caribbean reefs. Once nearly wiped out in the Caribbean by a mass mortality event in 1983, their recovery has been critical to reef health. Nocturnal, sheltering in rocky crevices during the day and actively grazing at night.
Diet & Feeding
Herbivore. Voracious grazer of macro algae, turf algae, and encrusting algae. One of the most powerful natural algae control invertebrates available for large reef systems.
Cautions
Venomous spines cause intensely painful punctures — handle only with very thick gloves. Never handle barehanded. Will topple unsecured frags and small corals. Requires a large tank with substantial rockwork and open areas to graze.