Erect rigid shrub or small tree, usually with patent spiny branches, 1.2–4 m. tall. Young branchlets quadrangular, grey-brownish, sometimes pubescent or glabrescent. Leaves simple, rarely 1-jugate, sessile to subsessile, 20–50 × 3–10 mm., oblanceolate to linear-oblanceolate, slender, rounded, retuse or emarginate at the apex, tapering at the base, more or less pubescent when young, glabrescent, margins entire, alternate on the young branchlets, 9–13 crowded together in each shortly lanate cushion on the older shoots; cushions always below the short spines. Flowers single or clustered on the cushions; pedicels 6–10 mm. long, pubescent. Calyx 5–9 mm. long, more or less 5-lobed, pubescent outside, sometimes glandular in the upper part. Corolla golden-yellow, sometimes with reddish streaks, with the tube 15 mm. long, minutely hairy in the throat and below the insertion of the stamens; lobes 15–19 mm. wide, subcircular, patent, crinkled, emarginate, margin ciliate. Stamens adnate up to c. 10 mm. from the base corolla tube; filaments 7–12 mm. long; anthers 3–4.5 mm. long, not apiculate. Ovary 2–3 mm. long. Capsule 5.5–10 × 1.1–1.5 cm. long, beaked; valves thin, light-brown. Seeds 1 × 1.8–2.2 cm., including the wings.
