Long-Spined Sea Urchin (Diadema setosum)

The Long-Spined Sea Urchin is a striking and effective invertebrate, easily recognized by its long, thin black spines and distinctive bright blue or orange ring around its mouth. Known for its algae-eating capabilities, it helps maintain a healthy reef environment by grazing on nuisance algae and keeping rock surfaces clean. Despite its peaceful nature, caution is advised when handling, as its spines are sharp and can cause injury.

Size: Typically grows up to 6 inches in diameter

Country of Origin: Indo-Pacific

Latin Name: Diadema setosum

Care Level: Easy – thrives in stable reef aquariums with ample hiding spots and moderate water flow

Long-Spined Sea Urchins are herbivores that graze on algae and detritus. They are reef-safe with caution, as their long spines can unintentionally damage corals or other tank inhabitants if the urchin is startled or moved.