Herbs perennial, to 1 m tall. Stems erect, obtusely quadrangular, branched in upper part, apex and young shoots densely glandular. Leaves alternate; petiole 1.5--3.5 mm, narrowly winged; leaf blade lanceolate, 5--10 X 0.8--2 cm, glabrous, reddish brown or black glandular punctate or striate near margin, base cuneate-attenuate, margin obscurely undulate, apex acute to subacuminate; veins 4 or 5 pairs; veinlets conspicuous abaxially. Racemes terminal, 8--13 cm; bracts subulate. Pedicel slightly angular, 5--7.5 mm, elongating to 1 cm in fruit. Calyx lobes lanceolate, 4--4.5 mm, with 4 vertical brown glandular stripes outside, margin membranous. Corolla pale purple, ca. 3.5 mm, shorter than calyx; tube ca. 1.5 mm; lobes narrowly oblong, ca. 2 X 0.8 mm, epunctate, apex obtuse; sinus between lobes obtuse. Stamens exserted; filaments adnate to base of corolla lobes, free parts ca. 3.5 mm; anthers ovate, dorsifixed, ca. 0.5 mm. Ovary glabrous; style to 4 mm. Capsule subglobose, slightly shorter than persistent calyx. Fl. Jun.