Fire algae or pyrrophyta is a type of unicellular algae that has two different flagella and yellow-brown color. Pyrrophyta contains different pigments of chlorophyll, which is why they can produce their own food. Dinoflagellates were once seen as a separate type of algae, but they are now classified as pyrrophyta.
Apart from dinoflagellates, other members of fire algae include Cryptomonads. Although dinoflagellates and Cryptomonads are both considered as members of fire algae, one of the major differences between the two is that the former has cell walls, whereas the latter does not have cell walls.
As said before, the pigments of chlorophyll in some members allow them to produce their own food; however, other members of pyrrophyta can't produce their own food. Out of all the members of pyrrophyta, dinoflagellates have a unique feature, and that is their ability to exhibit bioluminescence (the ability of a living organism to emit light).