Life-cycle of the cestode Wardium calumnacantha (Schmidt, 1963) comb. n. (Hymenolepididae) from common snipe, Gallinago gallinago (L.)

Post-embryonic development of the cestode Wardium calumnacantha (Schmidt, 1963) comb. n., a parasite of common snipe, was studied by experimental infection of the oligochaetes Neoscolex roseus Morev and Rhyacodrilus coccineus (Vejdovsky) carried out in Chukotka. The larvae of W. calumnacantha were ovoid and belonged to the morphological modification of cysticercoid-diplocyst. Two invaginations were observed during the larvogenesis. The first one occurred at the stage of scolexogenesis, when the body of larva was plunged into the external cyst formed by the walls of the primary cavity. Second invagination of the formed scolex and neck into the internal cyst was the final stage of cysticercoid formation.