The Prosthogonimidae are a family of parasitic flatworms. They are part of the huge of the suborder Plagiorchiata in the order Plagiorchiida. The adults of these parasites occur in the bursa of Fabricius, caecum, cloaca, liver, oviduct and sometimes even under the nictitating membrane of mammals and particularly birds. Selected genera are: \n* Cephalotrema \n* Mediogonimus Woodhead & Malewitz, 1936 \n* Ophthalmogonimus \n* Prosthogonimus Luhe, 1899 \n* Schistogonimus