Common name: violet sea urchin

General information

The Purple Sea Urchin, Sphaerechinus granularis, is a striking marine invertebrate known for its vibrant purple color and spherical shape with short, dense spines. It is a popular species among reef aquarium enthusiasts due to its unique appearance and the role it plays in the tank's ecosystem as an algae grazer.

Care

In captivity, Sphaerechinus granularis requires a tank with ample space to roam and a stable rock structure to cling to. They are generally hardy but sensitive to rapid changes in water parameters. A varied diet that includes algae and prepared sea urchin foods will help maintain their health and vibrant coloration.

Reproduction

In the wild, Purple Sea Urchins reproduce by releasing gametes into the water column during spawning events. In the aquarium, breeding is less common, but with optimal conditions, it is possible to observe spawning behavior.

Symbiosis

While not known for specific symbiotic relationships like clownfish and anemones, sea urchins play a crucial role in the reef ecosystem by controlling algae growth, which can benefit other tank inhabitants by maintaining a balanced environment.

Habitat

Sphaerechinus granularis is found in the Mediterranean Sea and the eastern Atlantic Ocean, from the British Isles to the coast of West Africa. They inhabit rocky substrates and seagrass beds, often at depths ranging from the intertidal zone to about 200 meters.