Disa hallackii Rolfe

Plants robust, up to 500 mm tall; leaves cauline, imbricate to subimbricate, narrowly lanceolate to lanceolate, acute, erect, reaching the inflorescence base. Inflorescences massive, 100-350 mm tall; bracts prominent, overtopping the flowers and partially obscuring them Flowers horizontal, sepals green on the back and white inside, petals purplish. Median sepal galeate, 15-18 mm tall and galea c. 4 mm deep, acute, narrowly oblong in outline; spur semi-pendent, sharply decurved, emarginate and subclavate, 5 mm long; lateral sepals suboblique, oblong, 10-16 mm long, apically navicular. Petals lorate, c. 6 mm long, wider near the apex, acuminate, basal half parallel to the anther, apical half curved upwards behind it, basal anticous lobe narrowly oblong, c. 3 mm long, flanking the stigma. Lip lanceolate to narrowly oblong, acute, 8-11 mm long. Anther and stigma horizontal; stigma equally tripulvinate; lateral rostellum lobes oblong, enclosing the globular viscidia.