Differential interference contrast (DIC) light micrograph of Tetraselmis tetrathele green algae. Tetraselmis algae are unicellular and move by using whip-like structures called flagella. They contain bright green chloroplasts and are found in both marine and freshwater ecosystems. Their habitat is limited by water depth due to their photosynthetic nature Magnification 360x when printed 10 centimetres wide.