About Eurythoe complanata (Pallas, 1766)
Commonly known as the iridescent fireworm, Eurythoe complanata (Pallas, 1766) individuals display a range of body colors from gray, green to pink. This species can reach a maximum length of 6 inches (150 mm). It has tufted respiratory branchiae that begin on the second body segment and extend along the remainder of the body. The fireworm has body bristles that produce a quaternary ammonium toxin called complanine, which causes a stinging sensation. This toxin acts as a defense against predators, and can also be used to stun prey. Eurythoe complanata is a carnivorous species that feeds on sponges, coral, mollusks, and other worms. It can ingest all of its food at once by expanding its lip to 4 to 5 times its original length. This species reproduces both sexually and asexually, with asexual reproduction occurring through regeneration. Eurythoe complanata inhabits most warm tropical and subtropical waters, including the Indo-Pacific, Atlantic Ocean, and Mediterranean Sea. It can be found at depths as great as 1,100 m (3,600 ft), and is most commonly encountered in shallow waters around rocks, boulders, and coral, as well as in small rock pools.
