Morphological Variability of Plagiorhynchus (Prosthorhynchus) Cylindraceus (Acanthocephala, Plagiorhynchidae) and Its Importance in Assessment of Taxonomy Structure of the Subgenus

Morphological variability in cystacanths and adults of P. (P.) cylindraceus (Goeze, 1782) Schmidt et Kuntz, 1966, type material of P. (P.) gallinagi Schachtachtinskaja, 1953 and P. (P.) gracilis Petrochenko, 1958 were studied. Data on intermediate hosts, definitive hosts and distribution of some species from the subgenus Prosthorhynchus were summarized. The taxonomy of the subgenus is discussed and names P. (P.) formosus Van Cleave, 1918, P. (P.) genitopapillatus Lundstr m, 1942, P. (P.) transversus Rudolphi, 1819, P. (P.) gallinagi and P. (P.) gracilis are placed as synonyms of P. (P.) cylindraceus.