Euglenophyta
"The euglenoids. Autotrophic (or sometimes derived heterotrophic) organisms with chlorophylls a and b. They store food as paramylon, an unusual carbohydrate. Euglenoids usually have a single apical flagellum of the tinsel variety and a contractile vacuole. The flexible cell wall (pellicle) is rich in proteins. Sexual reproduction is unknown. Euglenoids occur mostly in fresh water. There are some 450 species."
Biology of Plants, Fourth Edition, Worth Publishers Inc., Stanford University, Peter H. Raven and Helena Curtis, ©1971