||Hosts of this parasite are Oncorhynchus, Salvelinus, Thaleichthys, Gadus, Theragra, Gasterosteus, Aulorhynchus, Syngnathus, Brachyistius, Cymatogaster, Coryphopterus, Hexagrammos, Ophiodon, Blepsias, Dasycottus, Hemilepidotus, Nautichthys, Oligocottus, Ammodytes, Pholis, Aprodon, Lepidopsetta, Platichthys species (Ref. 94010). Members of the class Trematoda are parasitic, thus requires a host to survive. Life cycle: Eggs are passed on to the feces of the hosts. Embryos hatch into miracidia and penetrate the tissues of snails where they further undergo three stages: sporocysts (Ref. 833).