10 Post, George 9999 Colorado State University Cooperative Fishery Unit 9p. animal studies, cestoda (tapeworm subclass), Diphyllobothrium cordiceps, ecology, fish, habitats, invertebrates, lakes and ponds, parasites, westslope cutthroat trout (Oncorhynchus clarki lewisi), wildlife health, Yellowstone Lake, Diphyllobothrium in fis Diphyllobothrium cordiceps is a cestode parasite which exists in salmonid fishes of certain Yellowstone Park lake environments. The parasite is found primarily in the cutthroat trout of Yellowstone Lake, although it has been found in brook trout, rainbow trout and grayling in other lakes of the northern Rocky Mountains. NatureBib ID: 32543