| − | Any of various minute single-celled freshwater organisms of the genus Euglena, characterized by the presence of chlorophyll, a reddish eyespot, and a single anterior [[flagellum]]. | + | Any of various minute single-celled freshwater organisms of the genus '''Euglena''', characterized by the presence of chlorophyll, a reddish eyespot, and a single anterior [[flagellum]]. |