A new haplosphlanchnid cercaria, Cercaria kuwaitae VI sp. n., was found in the prosobranch snail Cerithidea cingulata in the Kuwait Bay. Details are presented on the morphology and behavior of the cercaria and the encystment process. The new cercaria is a biocellate, distome, with a prominent single sac-like intestinal cecum extending well posterior to the ventral sucker and develops in simple sporocysts. It differ from known haplosplanchnid cercariae in the absence of finger- like processes on the tail, and the presence of V-shaped excretory vesicle extending beyond ventral sucker and the presence of cervical glands. The surface topography of the cercaria and its sporocyst is examined by scanning electron microscopy. This is the first haplosplanchnid cercaria to be described from a Cerithidea species.
