STUDIES ON LARVAL STAGES OF DIGENETIC TREMATODES IN AQUATIC MOLLUSCS OF ISRAEL. 4. ON FIVE CERCARIAE FROM THE FRESHWATER SNAIL MELANOIDES TUBERCOLATA (MÜLLER, 1774)

ABSTRACT Five cercariae are described from the freshwater snail Melanoides tuberculata (Muller), collected near Kefar Masaryk in 1973: a gymnocephalous cercaria (Cercaria Levantina 9),. two pleurolophocercous cercariae (Cercariae Levantinae 10 and 11) and two xiphidiocercariae (Cercariae Levantinae 12 and 13). Details are presented on the morphology and swimming activities of the cercariae as well as on their development within and emergence from the snail. An instance of concurrent infection of one snail with a xiphidiocercaria and a gymnocephalous cercaria is mentioned.