 Species of "Lophius" have three long filaments sprouting from the middle of their heads; these are the detached and modified three first spines of the anterior dorsal fin.As with all Anglerfish species, the longest filament is the first, which terminates in an irregular growth of flesh, the esca (also referred to as the illicium), and is movable in all directions; this modified fin ray is used as a lure to attract other fish, which the monkfish then seize with their enormous jaws, devouring them whole.Whether the prey has been attracted to the lure or not is not strictly relevant, as the action of the jaws is an automatic reflex triggered by contact with the esca.