Thedinoflagellates(Greekδῖνοςdinos"whirling" andLatinflagellum"whip, scourge") are a large group offlagellateprotists. Most aremarineplankton, but they are common infresh waterhabitats, as well. Their populations are distributed depending ontemperature,salinity, or depth. Many dinoflagellates are known to bephotosynthetic, but a large fraction of these are in factmixotrophic, combining photosynthesis with ingestion of prey.[1]Dinoflagellates are the largest group of marineeukaryotesaside from thediatoms.[citation needed]Being primary producers makes them an important part of the aquatic food chain. Some species, calledzooxanthellae, areendosymbiontsof marine animals and play an important part in the biology ofcoral reefs. Other dinoflagellates are colorless predators on other protozoa, and a few forms areparasitic(see for exampleOodinium,Pfiesteria). Dinoflagellates produce resting stages, calleddinoflagellate cystsordinocysts, as part of their life cycles