Shrub c. 40-60 cm, much branched. Stems palish yellow or brown, quadrangular on younger shoots, pubescent with short ± spreading eglandular hairs. Leaves ± clustered, oblong-oblanceolate, entire, 10-20 x 5-8 mm, finely glandular-punctate and with short adpressed hairs, obtuse at apex, attenuate at base, spread over stem and merging into the bracts; spines c. 10 mm in axils. Verticillasters 6-10-flowered, all remote. Bracts several, hard-spiny, c. 10 mm long, pale-coloured, spreading-erect. Calyx ± densely pubescent to pilose and with sessile oil globules, clearly 10-nerved or ribbed; tube tubular-infundibuliform 7-8 mm, densely bearded in throat; limb straw-coloured, reticuulate nerved, broadly turbinate, asymmetrically lobed, often with intermediate irregular smaller lobes, all apiculate or toothed, larger lobes up to 7-8 mm, smaller 4-5 mm. Corolla 15-20 mm long, yellow or orange-yellow; tube c. 7 mm included within calyx; upper lip c. 12 mm long, ± falcate, vinous, long-bearded at margin. Nutlets c. 3.5 x 2.5 mm, obovoid, rounded at apex, not trigonous, often only one developing.