Robust herb to 1 m tall; tuber turbinate to hemispheric with flat base, vertical or horizontal with yellow or orange flesh, sometimes getting bluish exposed to air, 2.5-10.2 cm long and 1.5-7 cm wide, sometimes dividing in upper part; sap abundant; tunic fibrous, black. Outer leaves shorter than the inner, the most outer up to 20 cm long, spathe like at base, oblong in the upper part, acuminate at apex, about 2 cm wide; densely covered with tufted and 2-branched trichomes; inner leaves 5-9, dark green, lighter at base, creating a distinctive pseudostem 6-15 cm long, linear, rigidly coriaceous, erect, conduplicate, 30-130 x 0.5-2.2 cm, pilose with tufted whitish to silvery greyish hairs along margins and midrib and with 2-3-branched hairs on the lamina; veins 11-17, distinctive. Inflorescences 1-5, with scapes 30-70 cm long and 1.5-2.0 mm wide, slender, covered with long ascending greyish-white hairs, overtopped by the mature leaves. Flowers 3-14 (-23), alternate, in an up to 15 cm long spicate raceme; lower pedicels 0.6- 1.0 (-1.9) cm long, shorter towards the apex; bracts linear subulate, 12-26 mm long; tepals light yellow inside and green outside, outer tepals sometimes with red stripe, (5-) 12-18 long and 5-7 mm wide; outer tepals lanceolate, acute; inner tepals suboval and subacute; stamens equal, yellow or brown; filaments subulate, 1.3-2.5 mm long; anthers sagittate, fused apically, 3-6 mm long; ovary turbinate, green, 4-8 mm long and 3-5 mm wide; style 0.5-1 (-2.3) mm; stigma yellow, piramidal, 1-2 (-3.5) mm long. Capsule turbinate, 8 mm long, circumscissile, densely villose. Seeds glossy, black, globose, 1.2-1.7 mm in diameter with papillate testa, cuticle smooth.
H. rigidula var. rigidula is wide dispersed in the Democratic Republic of Congo, Uganda, Kenya, Tanzania, Angola, Zimbabwe, Mozambique, Republic of South Africa, Swaziland and Lesotho. It occurs in the Zambezian Region, the Kalahari-Highveld Transition zone, the Sudanian Region and the Somalia-Masai Region. Its centre of abundance is situated in the eastern part of the South Africa. In the East Africa it has one area of continuous range and two island locations. It reaches here North and East limits of its range. It is distributed between 800-2200 m a.s.l., especially often from 1400-2200 m a.s.l. in a lower part of the mountain vegetation zone belt. In the south-eastern part of Africa this taxon occurs almost from the see level (Snijman et al. 2003, Nordal et al. 2001), but its bottom limit of the vertical range is elevating rapidly in the North. In the Democratic Republic of Congo the most western location is situated 1600 m a.s.l. (this study).
Grassland dry or wet, bushland, open woodland, seepage bog, fallow maize field, in full sun; laterite or black soil (pH 6-6.8) rich in humus.
Medical: Tubers are given to chickens as a cure. Magical: A cut tuber is used in a charm against extensive rain. Forage: Leaves nibbled by animals. The tubers are eaten by monkeys.