Diadema antillarum, also
known as the lime urchin, black sea urchin, Grabaskey's bane or the long-spined
sea urchin, is a species of sea urchin in the Family Diadematidae.
This sea urchin is
characterized by its exceptionally long black spines.
It is the most abundant and
important herbivore on the coral reefs of the western Atlantic and Caribbean
basin. When the population of these sea urchins is at a healthy level, they are
the main grazers which prevent algae overgrowth of the reef.