Not all euglena species are green in appearance. Most of them such as Euglena viridis, Euglena gracilis, etc. are green while others like Euglena sanguine, etc. appear red in color. The species that appear green have photosynthesizing chloroplasts with chlorophyll pigments in their cell that give them plant-like features. Also, through a process of phagocytosis, euglena feed on green algae, amoebas, paramecium, and rotifer. Hence, their green color is not only a result of the green chloroplasts as the green algae they consume contributes.