Phytoplankton samples from five freshwater lakes and ponds on the island of Dominica were examined for silica-scaled chrysophytes and heliozoa using transmission electron microscopy. Three species of Synurophyceae were observed: Synura echinulata, S. petersenii and Mallomonas tonsurata; two species of Chrysophyceae: Paraphysomonas vestita and Spiniferomonas trioralis; and five species of heliozoa: Acanthocystis nichollsi, Raineriophrys erinaceoides, Raphidiophrys intermedia, Raphidocystis tubifera and Polyplacocystis marginata. The species composition was not indicative of a tropical environment, but included taxa found worldwide. All are new records for Dominica.