About Chondrocidaris gigantea A.Agassiz, 1863
Chondrocidaris gigantea, commonly called the rough-spined sea urchin, grows to 20 to 25 cm (8 to 10 inches) in diameter, with each of its spines reaching 15 cm (6 inches) in length. Its spines have thorns that provide a surface for algae and sponges to grow on. The algae and sponges that grow on the spines then provide camouflage for the sea urchin. The number of spines this species has varies by region: for example, individuals found in Mauritius only have 5 spines, while individuals in Hawaii can have up to 10. The rough-spined sea urchin is primarily an herbivore, and most of its diet is made up of algae that grows on coral reefs. The rough-spined sea urchin is distributed in the Central Pacific, including Hawaii, New Guinea and French Polynesia, and also occurs in Mauritius. It prefers coral reef habitats in water deeper than 150 ft (46 m), and uses surrounding coral for cover.
