Common name : shingle urchin, cliff-clinging urchin, helmet urchin or rock urchin
Aspect : shell in the shape of a flattened dome covered with purple "radioles" which form a sort of nested scales. This particular shape allows it to offer no grip on the waves. The lower surface equipped with powerful suckers which can retract or lengthen, in order to allow it to move or else to cling to rocks.
Feeding : periwinkle, other sea urchins, coral algae
Environment : warm waters, coastal rocks
Colobocentrotus (Podophora) atratus (Linnaeus, 1758)