Broad Fish Tapeworm Diphyllobothrium latum
Some flatworms, including tapeworms, have become highly modified and live as parasites. The broad fish tapeworm has a complex life history. It begins life as a fertilized egg that is eaten by tiny freshwater crustaceans, inside which the larvae hatch. Freshwater, estuarine, and migratory marine fish, (such as salmon) become infected by the larvae when they eat either the crustaceans or other infected fish. The adult broad fish tapeworm lives in fish-eating mammals and may infect humans who eat raw fish. Other tapeworm species live as adults in the guts of marine fish.