Studies on the trematode parasites of Indian fishes

Abstract

THE family Heterophyidee Odhner (1914), on account of its importance both in medical and veterinary sciences, has attracted considerable attention of many writers. Ransom (1920) made the first attempt to gather all the known forms in the family Heterophyidoe. This was followed by Ciurea (1924), Poche (1926), and Fuhrmann (1928), who have given their respective classifications of the family Heterophyidee, but the latest and the most comprehensive systematic treatment of the family is that given by Witenberg (1929) where he recognised the following sub-families (1) Centrocestinoe, (2) Heterophyinae, (3) Cercarioidinoe, (4) Haplorchina, (5) Adleriellinee. Almost all the forms described by him in these five sub-families are, as a rule, parasites of mammals and birds, usually fish-eaters, fish being one of the intermediate hosts ; Haplorchis cahiranus Looss (1899) being the only form from fish included by him in the family Heterophyidae. Fuhrmann (1928) included Crvptogonimus chyle Osborn (1903), a form from fish, in the family Heterophyidae, and this has been supported by Van Cleave and Mueller (1932-34), who have further described six genera—A cetodextra, Cryytogonzmus, Ccecincola, Centrovarium, Neochasmus and Allacanthochasmus—in the family Heterophyidoe, as of regular occurrence in fishes ; and further they have erected a new sub-family Neochasminae to include the genera Neochasmus and Allctcanthochasmus. Witenberg (1929), in his account of the family, recognised two genera —Haplorchis and Monorchotrema—under the sub-family Haplorchinae, but in a subsequent communication (1930) he has corrected his statement by making Monorchotrema as synonym of Haplorchis and has further suggested the removal of Haplorchis cahirinus from the genus Haplorchis. Gohar (1934), while describing Haplorchis pumilio and Haplorchis milvi, raised the