REDESCRIPTION OF ECHINOSTOMA-TRIVOLVIS (CORT, 1914) (TREMATODA, ECHINOSTOMATIDAE) WITH A DISCUSSION ON ITS IDENTITY

The life-cycle of Echinostoma trivolvis (Cert, 1914) has been complete d experimentally and the validity and identity of this species are dis cussed. Synonyms for cercariae and adults of E. trivolvis are as follo ws: Cercaria trivolvis Cert, 1914, C. trisolenata Faust, 1917, C. acan thostoma Faust, 1918, C. complexa Faust, 1919; Distoma echinatum Zeder , 1803, of Leidy (1888, 1904) and Hassall (1896); E. echinatum (Zeder, 1803) of Hassall (1896), Stiles & Hassall (1895), Barker & Laughlin ( l911), Barker (1916) and Swales (1933); E. revolutum (Frolich, 1802) D ietz, 1909 of Johnson (1920), Fallis (1934), Beaver (1937) and Fried & co-workers (1968-1989); E. armigerum Barker & Irvine, 1915; E. coalit um Barker & Beaver, 1915; E. callawayensis Barker & Noll, 1915; E. par aulum Dietz, 1909 of Miller (1937); E. multispinosum Vigueras, 1944; a nd Echinoparyphium contiguum Barker & Bastron, 1915. The first interme diate host is the planorbid snail Helisoma trivolvis. Second intermedi ate hosts are various pulmonate and prosobranch snails, mussels, plana rians, fishes, frogs, tadpoles and freshwater turtles. Final hosts are various birds and mammals. E. trivolvis occurs only in North America.