Complanine was the first compound isolated from the fireworm which causes these effects. Complanine is a quaternary ammonium compound isolated from the marine fireworm "Eurythoe complanata". The transcriptome of the bearded fireworm was sequenced and annotated in 2015. It is presumed that this compound's function is to deter predators of the fireworm. In the books, Snotlout has a Monstrous Nightmare dragon named Fireworm. The bearded fireworm lives throughout the tropical coastal waters of the Atlantic Ocean. The bearded fireworm is a voracious predator that supplements its diet with plant material. The fireworm ("Hermodice carunculata") sometimes grazes on it, but prefers other corals.