The Mediterranean is home to many unique marine creatures, and among the most striking is the long-spined sea urchin (Centrostephanus longispinus, Maltese: Rizza tax-xewk twal). With its elegant, ultra-long spines and dark, spherical body, this deep-sea dweller is a fascinating sight for divers exploring the waters around Malta, Gozo, and Comino.

Typically found between 10 and 200 meters deep, this sea urchin prefers rocky seabeds, underwater caves, and rhodolith beds. Though mainly active at night, it often clings to rocks or hides in shaded areas during the day. Its body measures around 4 to 6 cm, but with spines extending up to 30 cm, its total size can reach an impressive 40 cm. Colours range from dark purple and brown to black, occasionally with stripy patterns and small red spines visible beneath.

Despite its delicate beauty, this species should never be handled. Its brittle, venomous spines can break off under the skin, causing pain, redness, and localised reactions. While not life-threatening, stings are unpleasant and may require medical treatment. Always wear protective footwear in rocky or deep areas and avoid touching marine life.

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Beyond its appearance, the long-spined sea urchin plays a vital ecological role. As a herbivore, it feeds on algae, helping to regulate growth and maintain balance within deep-sea ecosystems. Think of it as a discreet, prickly underwater cleaner, quietly supporting biodiversity on the sea floor.

So next time you’re diving in Maltese waters, keep an eye out for this remarkable creature.

Admire it from a distance - and let it do its important work undisturbed!