shed, use of the crushing method is preferred
(Karvonen et al. 2006a). In contrast, if the infections
are old and most of the cercariae are fully developed
and ready to shed in August (Karvonen et al. 2006a),
the emergence method is suitable for examining the
parasites. Cercariae were identified based on their
morphology and resting posture: those hanging down
at rest with the tail stem bent at an angle of 90 and
the furcae spread apart at an angle 180 were
classified as Diplostomum sp. (Niewiadomska 1986