An erect, up to 1 m tall undershrub with 4-angled, glandular-pubescent Leaves dimorphic, basal main stem leaves oblong-lanceolate, 5-10 (-12) x 1.5-4 cm, glabrous, lateral nerves 4-5 pairs, acute or acuminate, mucronate, entire, tapering basally into 5-25 mm long petiole; upper leaves much smaller and subsessile, elliptic-lanceolate, 1.5-2.5 cm x 7-9 mm, glandular-pubescent, cuspidate. Flowers white, in terminal, lax or dense, up to 15 cm long spikes; elliptic-oblong or obovate, 9-12 x 4-6 mm, acute, spine-tipped, glandular bracteoles lanceolate, 6-8 mm long, spine-tipped, glandular-pubescent. unequally 5-lobed to the base, 1-1.2 cm long, lobes glandular hairy, 2 outer lanceolate, spine-tipped, 2 inner lobes linear, acute. Corolla pubescent externally, 1.2-1.6 cm long; upper lip ovate, purple-streaked, entire or emarginate; lower lip with 3, rounded lobes. Staminal filaments glabrous with bearded anthers. Ovary glabrous, style hairy. Capsule ovoid-lanceolate, c. 8 mm long, glabrous, 4-seeded. Seeds ovoid, c. 2.5 mm long, flattened.