The precise location of sensillae of the cercaria of E. trivolvis is d
escribed. This study allows one to distinguish E. trivolvis from E. re
volutum, E. echinatum, E. caproni, E. jurini and E. parvocirrus on the
basis of the arrangement of the argentophilic structures of their cer
cariae. She arrangement of the tegumentary receptors of the circle AI
dorsal (AID) complex allows for clear differentiation of the cercariae
of E. trivolvis from the cercariae of all trematode species studied b
y silver nitrate staining in the genera Echinoparyphium, Hypoderaeum,
Moliniella, and Paryphostomum in the family Echinostomatidae.