The image shown is a representative illustration and does not depict every individual animal in this category.
Total number of species approx.: 950
Sea urchins are small, round marine animals covered in sharp spines, found in oceans around the world from shallow reefs to deep waters. They belong to the group of echinoderms, related to starfish, and move slowly using tiny tube feet. Most sea urchins are herbivores, grazing on algae and helping to keep reef surfaces clean. Their feeding activity plays a key role in maintaining balance within marine ecosystems.
Sea urchins have a unique feeding structure known as “Aristotle’s lantern,” a complex set of jaws used to scrape food from rocks and coral. Their spines provide protection from predators and can sometimes be venomous. While important for healthy reefs, sea urchin populations must remain balanced. Too many urchins can overgraze habitats, while environmental changes like pollution and climate shifts can threaten their survival.