Magnificent Fire Urchin - Asthenosom varium
The Asthenosoma varium is called Fire Urchin for the red colours associating it with fire but also for the intense pain if stung by them.
Some Crustaceans lives commensally with them and in the picture, a small Zebra Crab can be seen on it.
''Asthenosoma varium'' is a sea urchin. Growing up to 22 cm in diameter, it lives on sand and rubble sea bottoms in the Indo-Pacific, from the Red Sea to Australia and Southern Japan. It plays host to the commensal shrimp ''Periclemenes colemani'' and the zebra crab, ''Zebrida adamsii''.