Description from Flora of China
Herbs, erect, 40-80 cm tall. Lateral roots fusiform. Stems quadrangular, glabrous. Leaves opposite; petiole 1.5-3 cm, glabrous; leaf blade ovate, 5-11 X 2.5-5 cm, base truncate to cuneate, margin regularly serrate and often double serrate, apex acute; midrib abaxially raised; lateral veins 3 or 4 on each side of midrib. Thyrses terminal, narrow, 5-10 X ca. 2 cm; cymes 1-5-flowered; peduncle 3-5 mm, often glandular pubescent; bracts linear-lanceolate, 2-4 mm, glabrous, margin entire. Pedicel 0.5-1.5 cm, erect, sparsely glandular pilose. Calyx campanulate, glabrous; lobes oblong to ovate, ca. 3 X 1.5-2 mm, apex obtuse to rounded. Corolla yellow-green, ca. 5 mm, glabrous; tube ca. 3 mm; lower lip ca. 1 mm, lobes orbicular and ca. 1 mm in diam.; upper lip fanlike, ca. 2 mm, lobes orbicular and ca. 1.5 mm in diam. Stamens included; filaments glandular pilose; staminode fanlike. Style ca. 3 mm; stigma capitate. Capsule ovoid, ca. 5 X 3 mm. Fl. and fr. Aug-Sep.
* 2600-2800 m. Yunnan (Lijiang Naxizu Zizhixian, Eryuan Xian).