Description from Flora of China
Herbs perennial, rhizomatous. Stems 25-50 cm tall, erect, 1.2-2 mm in diam., reddish, subglabrous or slightly pubescent, few branched. Leaves 4-paired; petiole 7-12 mm, reddish, glandular pubescent; leaf blade dark reddish green abaxially, narrowly oblong to ovate, 3-11 × 1-4.5 cm, glabrous, abaxially with dense, small, impressed glands, base cuneate to rounded, margin sparsely denticulate to subentire or shallowly 2-6-serrate, apex acuminate to short acuminate. Racemes terminal, axillary, 9-15 cm; peduncle 2.5-3.5 cm; bracts reduced. Pedicel 2-2.5 mm, densely puberulent and glandular pubescent. Calyx purple-red, ca. 2 mm, to 3 mm in fruit, puberulent; scutellum spreading, semicircular, ca. 1.5 mm, to 4 mm in fruit. Corolla limb purple-red, 1.5-1.7 cm, puberulent outside; tube reddish or white, 1-1.2 cm, base bent, to 4 mm wide at throat; lateral lobes of lower lip ovate, ca. 3 mm wide, apically emarginate. Nutlets triquetrous, ovoid, ca. 0.75 × 0.5 mm, dark brown, tuberculate, adaxially elevated, umbonate on central part. Fl. Apr, fr. May.
* Forested hillsides, thickets; 500-1600 m. Guizhou, Sichuan, Yunnan