Description from Flora of China
Herbs perennial, 40--80 cm tall. Stems elongate, reclining to procumbent, rarely branched. Stems, petioles, and pedicels with dense rust-colored multicellular hairs. Leaves opposite; petiole 0.5--1.5 cm; leaf blade ovate to broadly ovate, rarely suborbicular to ovate-oblong, 1.5--3 X 1--2.2 cm, densely bristly, transparent glandular striate, stripes visible with transillumination, base cordulate to truncate, apex acute to obtuse; abaxially midvein and 3 pairs of lateral veins rust-colored pilose. Pedicel recurved in fruit, 0.6--2 cm. Flowers solitary, axillary. Calyx lobes lanceolate, ca. 5 X 1 mm, pubescent, apex acute, cristate; crest ca. 1 mm wide at upper part. Corolla yellow; tube ca. 2.5 mm; lobes oblong-lanceolate, 7.5--9.5 X 3.5--4 mm, inconspicuously brown glandular striate, apex acute. Filaments connate basally into a ca. 3 mm high tube, free parts 2--4 mm; anthers oblong, dorsifixed, opening by lateral slits, ca. 1.2 mm. Ovary glabrous; style ca. 6 mm. Capsule subglobose, ca. 4 mm in diam. Fl. Jun.
* Forest margins; ca. 2100 m. W Sichuan, NE Yunnan.