Distigma sennii Pringsheim, 1942. Metabolic swimming euglenid, cell typically club-shaped, broader anteriorly and truncated with an apical canal-opening, the posterior end of cell tapers, cells are 40 - 62 microns long. With two flagella, unequal in length. The longer flagellum is about 0.25-0.35 cell length and the recurrent flagellum is very short (5 - 6 microns), slightly curved and directed sideways or to the posterior of the cell. The pellicle seems smooth. The reservoir is in the middle of the cell with an associated contractile vacuole. A nucleus is located centrally or slightly behind the centre of the cell. The cell contains a large number of ellipsoidal or cylindical refractile grains and when swimming the cell moves quickly and rotates.