Description from Flora of China
Herbs perennial, 15--180 cm tall or long. Stems single or few, erect to reclined, quadrangular, with short wings on ridges. Leaves opposite, subsessile or petiole to 8 mm; leaf blade elliptic to broadly ovate, 2--10 X 1.2--5 cm, finely papillate, abaxially densely minutely glandular, adaxially glabrous or ± bristly, base subrounded to broadly cuneate, margin obscurely undulate, apex acute; veins 5--7 pairs, raised abaxially. Pedicel 2--3.5 cm. Flowers 1 or 2(--4), in axils of medial and upper leaves. Calyx lobes ovate, ca. 6 X 1.8 mm, apex acuminate to subulate, costate. Corolla yellow, ca. 8 mm, deeply parted; lobes broadly obovate, ca. 7 X 5 mm, apex obtuse. Filaments connate basally into a ca. 0.5 mm high ring, free parts very short; anthers ca. 2.5 mm, basifixed, opening by short slits. Style ca. 4.7 mm. Capsule subglobose, ca. 4 mm in diam., shorter than calyx.
* In shrubs on mountain slopes, clearings at margins of mountain woodlands; 2200--2400 m. SW Sichuan, S, SW, and W Yunnan