Sphenomonas teres (Stein, 1878) Klebs, 1893. Rigid, gliding euglenid, cell shape elongate elliptical, anterior end of cell narrow, apically oblique with slight neck and reflexed collar. Cell is about 11 - 30 microns long. Posterior end of cell also narrow, slightly pointed.or papillated. Two flagella insert in the flagellar pocket, unequal in length. The anterior flagellum is about the same length as the cell or slightly longer. The second flagellum is about one quarter the length of the cell. The flagellar pocket is located dorsally and has an associated contractile vacuole. Pellicle with at least 6-8 delicate, longitudinal ridges, spaced about 1.5 - 2 microns Typically there is a large hyaline inclusion of cell located more or less in the posterior part of cell. Cell contain a few small roundish paramylon grains in the posterior part of cell and some more in the anterior part of cell. T Clostenema sociale Stokes synomised by Huber-Pestalozzi, 1955
