Phyllosoma larva of Spiny lobster (Palinurus sp) riding a Purple jellyfish (Pelagia noctiluca), at night in surface waters of the deep ocean off Kailua Kona, Hawaii, August. The larval crustacean uses its cnidarian host both as a food source, and as a defensive weapon, spinning it around to deter predators with the stinging tentacles of the jellyfish.