Two new protistan species were observed in a blenniid fish, Scartichthys viridis, inhabiting tide pools at Las Cruces, central Chile. Trypanoplasma ojedae sp. n. (Mastigophora: Kinetoplastida) in the blood is characterized by its small size (29.8 +/- 5.0 x 5.1 +/- 1.2 mu m), short anterior flagellum (4.9 +/- 0.6 mu m), anterior located kinetoplast (2.4 +/- 0.2) and a prominent undulating membrane. All of 18 fish were infected and 67% were parasitized on the gills by an unidentified piscicolid leech that harbored developing and infective biflagellated stages. Trichodina lascrucensis sp. n. (Ciliophora: Peritrichida) parasitized the gill fillaments of all fish. The ciliate is characterized by its body size (70.8 +/- 8.4 mu m), adhesive disc (53 +/- 5.4 mu m), denticular ring (33 +/- 3.1 mu m), mean number of denticles (32.8 +/- 3.0), mean number of denticular pins (9.5 +/- 1.0) and ovoid micronucleus located near to one of the macronuclear arms. Since none of the two parasites was similar to any species described from marine tide pool habitats as well as from the Pacific Ocean, both are considered new species with the characteristics described herein.