Abstract: | Investigating Mollusca prosobranchia of the Bithyniidae family in the water reservoirs of the Novosibirsk Region in 1994-1998 first revealed that Codiella troscheli had the trematode Metorchis albidus (Braun, 1893). The species affiliation of the trematode was experimentally verified. This paper presents the results of studies of the seasonal and daily emission of M. albidus cercariae and data on their longevity in the environment, on the ability of the cercariae to live in fish and that of metacercariae in the body of a definitive host. The studies have indicated that not only the trematode Opisthorchis felineus, but also C. troscheli may develop in the C. troscheli mollusks, which should be taken into account in both describing the natural foci of opisthorchiasis and diagnosing opisthorchiasis and metorchiasis. |