This Rough-Spined Urchin (Condrocidaris gigantean), photographed at night, is rarely seen during the day. Because their spines are not covered with living skin, the spines are often encrusted with corals and algae. This urchin is carrying a large crop of Porites coral on its spines. Like other sea urchins, this urchin generally eats algae, but will eat anything it finds that doesn�t escape its tube feet.

This sea urchin was photographed at night in about 35 feet of water off the south Kohala Coast near the Mauna Lani Resort on the Big Island of Hawaii.