Rigid shrub. BRANCHES pairs at right angles to each other; bearing straight thorns that are grey and densely woolly at first, becoming brown-black later. LEAVES simple, obovate to oblong; densely grey-woolly, paler below than above; veins prominent below; margin toothed and wavy. FLOWERS solitary, trumpet-shaped with long tube; white to pale pink. FRUIT a woody, warty capsule that rattles when shaken and splits open when the seeds are ripe. (from Tree Atlas of Namibia)

Spiny shrub or very small tree armed with slender straight spines. Leaves in fascicles, sometimes opposite, densely covered in silvery-grey hairs, oblong; margins coarsely dentate or crenate. Flowers axillary, solitary, large and showy, white, sometimes tinged with pink with a long yellowish corolla tube. Fruit a thickly woody capsule, warty, greyish-brown when ripe, splitting to release winged seeds. (from Flora of Botswana website)