Euglena ehrenbergii is a single-celled protist belonging to the genus Euglena. It has an elongated, spindle-shaped cell with a flexible pellicle and a single whip-like flagellum used for movement. The organism features an eyespot for light detection and contains chloroplasts responsible for photosynthesis, giving it a greenish color. Euglena ehrenbergii stores paramylon as a carbohydrate reserve and can adapt to varying environmental conditions, thriving primarily in freshwater habitats.