Dinoflagellata

Dinoflagellata is a phylum of single celled eukaryotic organisms, most of them aquatic and propelled by two dissimilar flagella, that occupy a place at the boundary between plants and animals because many species photosynthesize while others are predators or parasites. Dinoflagellates are a major component of marine and freshwater plankton, and certain species are responsible for the phenomenon of bioluminescent waves as well as harmful algal blooms, sometimes called red tides, that can produce toxins affecting shellfish, fish, and the people who eat them.