A sumo crab carrying a radiant urchin for protection.

The crab grasps and holds spines of the urchin with four of its legs.

(Madidir, Lembeh Strait, Sulawesi, Indonesia)

arthropod; crustacean; decapod; crab; sumo crab; urchin crab; Arthropoda; subP Crustacea; Malacostraca; Decapoda; subOrder Pleocyemata; infraOrder Brachyura; superFamily Dorippoidea; Dorippidae; Dorippe frascone; 

echinoderm; urchin; sea urchin; radiant sea urchin; Echinodermata; Echinoidea; Diadematoida; Diadematidae; Astropyga radiata; commensal behavior, South Pacific