Polymorphus(redirected from Polymorphus magnus)
a genus of thorny-headed worms in the phylum Acanthocephala.
found in the posterior part of the small intestine of many domesticated and wild birds including ducks and fowls. Causes anemia, wasting and enteritis, and heavy infestations cause death losses in colonies of aquatic birds.
causes death losses in eider duck colonies.
found in the intestines of wild anseriform birds.