Revision of Mediorhynchus van cleave 1916 (acanthocephala) with a key to species.

Species characters in Mediorhynchus are discussed, and a consistent method of describing hook arrangement, longitudinal rows, is proposed. Mediorhynchus papillosus Van Cleave 1916, and M. orientalis Belopol'skaya 1953 are redescribed, and M. edmondsi sp. n. is described from Palawan. The new species is most similar to M. rodensis Cosin 1971 in armature, but differs from it in proboscis shape and overall size. Among other new records are M. gallinarum (Bhalerao, 1937) in chickens in Palawan, and M. turnixena (Tubangui, 1933) from a button quail in Palawan. Several synonymies are pointed out and several unidentifiable species are mentioned. A key to 29 species recognized as valid is provided.