The parasitic worm Heteracanthocephalidae belongs to the Kingdom: Animalia, Phylum: Acanthocephala, Class: Palaeacanthocephala, and Order: Echinorhynchida (which also includes other parasitic worms like Cavisomidae and Illiosentidae).
The parasitic worm Heteracanthocephalidae belongs to the Kingdom: Animalia, Phylum: Acanthocephala, Class: Palaeacanthocephala, and Order: Echinorhynchida (which also includes other parasitic worms like Cavisomidae and Illiosentidae).