Dinoflagellates like Gonyaulax cause red tides when the colour of the sea appears red due to the large abundance of fire algae Gonyaulax so it is known as the “Red Tide".
Dinoflagellates are unicellular, photosynthetic, and a biflagellated group of protists, they are commonly known as whorling whips.
Some of the dinoflagellates are bioluminescent algae, they have pigment luciferin, which is acted upon by the enzyme luciferase causing the production of light.
Dinoflagellates are mostly marine plankton, but also found in freshwater habitats.