Studies on the Helminth Fauna of Alaska. XLII. \u3ci\u3eAploparaksis turdi\u3c/i\u3e sp. n., a Hymenolepidid Cestode from Thrushes

Aploparaksis turdi sp. n. (Cestoda: Hymenolepididae) is described from the robin, Turdus migratorius L., and recorded also from the varied thrush, Ixoreus naevius (Gmelin), from Iliamna Lake, upper Alaska Peninsula. This cestode is distinguished from the three previously known species of Aploparaksis s. l. occurring in passeriform birds by the size and number of rostellar hooks and by the arrangement and proportions of the genital organs. It is concluded that the validity of the genus Monorcholepis Oshmarin, 1961, to which certain of these species have been assigned, is questionable, and the latter genus is considered to be a synonym of Aploparaksis Clerc, 1903