tapeworms (cestoda: caryophyllidea), parasites of fish under the microscope for education

catfish parasitic fish larva muscle slide laboratory whipworm eggs japonicum diphyllobot cyst roundworms taenia solium caryophyllidea cestoda freshwater background cell cysts helminth parasitology proglottid scientific hook cestode tissue samples zoology rostellum flatworm magnification microscopy host infection intestine head scolex tapeworm biology medicine platyhelminthes microscopic disease medical microscope worm parasite