A much branched shrub armed with (1-) 2-4, greyish-white, 1-2 cm long sharp, axillary spines. Leaves on 0-2.5 cm long petiole; lamina elliptic or ovate-elliptic to obovate, (4-) 6-12 (-17) x 2-5 (-6) cm, sparsely pubescent beneath, scabrid-lineolate above, attenuate, entire, ciliate, bristly acuminate. Flowers large, golden-yellow, up to 7 cm long, often sessile and solitary lower leaf-axils, in short terminal spikes above; bracts oblong or oblong-lanceolate, 1-2.5 cm x 3-5 mm, keeled, glabrous or sparsely hairy on keel, acute, spine-tipped; bracteoles linear-subulate, 10-20 mm long, spinescent. Calyx lobes spine-tipped, outer 2 lobes broadly oblanceolate, 1.5-1.7 cm long, acuminate, glabrous, inner ones narrowly ovate-lanceolate, 10-12 mm long, mucronate; Corolla c. 1.5 cm across, pubescent to glabrous outside, tube 2-2.5 cm long; limb nearly as long as tube, lobes oblong-ovate, obtuse. Fertile stamens 2 with exserted filaments, anthers 2-6 mm long; stminodes 2 with short filaments, included, hairy at insertion. Ovary c. 3.5 mm long; style up to 4 cm long. Capsule ovoid-conical, 1.5-2 cm x 8-10 mm, beaked, 2-seeded. Seeds ± orbicular, c. 6 mm long, 5 mm across, appressed hairy.