Of 14,431 Clypeomorus bifasciata Sowerby, 1855 collected from Kuwait Bay between November 1992 and October 1993, 718 (5.0%) were shedding a total of 12 morphologically distinguishable ‘types’ of cercariae: 1 cystocercous, 2 echinos-tome, 1 furcocystocercous, 3 magnacercous, 2 megalurous, 1 microcercous and 2 ubiquità. Ubiquità I and furcocystocercous were the most prevalent species accounting for 66% and 25%, respectively, of total cercaria fauna. Double infections were recorded in only 6 (0.8%) of the infected snails. The overall prevalence of C. bifasciata shedding cercariae was highest (6-10%) in spring and summer, and species diversity was highest (11 species) in fall and spring. Seasonal variations in prevalence and diversity of cercariae were related to environmental factors and hosts behavior.