Protists both and multicellular that possess two different types of flagella during their motile .
Included among the stramenopiles are the brown algae ( or ), golden algae ( or ), diatoms ( or ), and ( or ).
The chloroplasts of the stromanopile posses four membranes versus the two of cyanobacteria, that is, the inner membrane and the outer membrane>. The possession of these four membranes by these chloroplasts may or may not imply secondary endosymbiosis and potentially even .
If a case of secondary endosymbios (or higher), then it is likely that the chloroplasts represented captured red algae.