Rough-Spined Urchin

Chondrocidaris gigantea

Chondrocidaris gigantea is a large sea urchin that typically reaches diameters of 20 to 25 cm, with spines extending up to 15 cm in length. Its spines are distinctive, featuring thorns that support the growth of algae and sponges, providing effective camouflage against predators. The number of spines can vary by location; for instance, individuals in Mauritius may have only five spines, while those in Hawaii can have up to ten. This species is primarily herbivorous, feeding mainly on algae found on coral reefs, which are its preferred habitat. The rough-spined urchin inhabits the Central Pacific, including regions such as Hawaii, New Guinea, and French Polynesia, as well as Mauritius. It favors coral reefs at depths greater than 46 meters, often using the surrounding coral for protection. Encounters with this species while diving can reveal its unique adaptations and the ecosystems it supports. Chondrocidaris gigantea has not been evaluated for conservation status, and it is considered harmless to humans. Its breeding habits and life cycle details are not extensively documented in the sources, but its role in the reef ecosystem as a herbivore is well established.