Euglenophyta A division of typically unicellular protists, sometimes regarded as algae, sometimes as protozoa (class Phytomastigophora). They are characterized by the possession of a single flagellum, the formation of paramylum as a storage product, possession of chlorophylls a and b, and the absence of sexual reproduction. Vegetative cells lack a cell wall but possess a proteinaceous pellicle. There are many genera, the best known of which is Euglena. They are found in a wide range of aquatic habitats: ditches, ponds, puddles, and rivers (especially those polluted with organic matter). Some species occur in brackish or marine waters.

euglenophyte Any member of the phylum Euglenophyta comprising single-celled algae, including the genus Euglena. Members of this group have both animal and plant characteristics. They swim by means of flagella. Many species contain chloroplasts and employ photosynthesis, but some are colourless and feed on bacteria and diatoms.