The phylum Annelida is characterized by the presence of segmented worms. Usually found in marine environments some are also fresh water and terrestrial. Polychaetes are separated from the rest of the annelids by the presence of parapodia and chaetae. A pair of parapodia is located on each segment and on each parapodia multiple chaetae (bristles) can be found. The order Amphinomida is one of nine that have an eversible mouth and calcareous chaetae. The family Amphinomidae is easily recognized as the fireworms as most members have hard, calcareous, brittle chaetae that break off when touched. They are also a long and elongated rectangular shape where as their sister family Eunicida contains specimens that are usually as long as they are wide. The Eurythoe genus is separated by an elongated caruncle and different microhabitats (Edmonds et al. 2000).