(1) the flagella are located in endocytic vacuoles and remain beating; (2) the axostyle and the costa are not depolymerized but present a curved shape; (3) the axostyle does not exhibit staining with antitubulin antibodies when the mitotic spindle is observed; (4) the mitotic process occurs within pseudocysts but differs from that described for trophozoites; (5) a nuclear canal is formed connecting the two spindle poles; and (6) the process is reversible if the cells are transferred to fresh medium.