Porcupinefish

Habitat:

Found in all the tropical and subtropical waters of the world, including the Mediterranean Sea. Juveniles are pelagic up to the time that they are about 20 cm in length. Adults favour lagoons, top reefs and seaward coral or rocky reefs from one to 50 m depth, sheltering under ledges or in caves during the day.

Notes:

Found this big guy hiding in the nooks of the rock pile, but he came out to check me out while I snorkeled over him (her?).