Herbs perennial, 15--30 cm tall, ± fragrant when dry. Stems of previous year decumbent, rooting at nodes. Stems of current year ascending to erect, conspicuously quadrangular or weakly winged. Leaves alternate; petiole 0.8--1.2 cm; leaf blade ovate to broadly ovate, 1.5--3.2 X 1--2.2 cm, abaxially glabrous, adaxially ± bristly, base truncate to subcordate, rarely rounded, margin obscurely undulate, apex acute to apiculate; veins 3 or 4 pairs, lowest pair often basal; veinlets prominently reticulate abaxially. Pedicel ca. 2.5 cm. Flowers solitary, axillary. Calyx lobes lanceolate, 5--6 X 1--1.3 mm, abaxially costate, apex subulate. Corolla yellow, deeply parted; tube ca. 1 mm; lobes oblong, ca. 9 X 3 mm, apex obtuse. Filaments very short; anthers ca. 3 mm, basifixed, opening by apical pores. Capsule ca. 3 mm in diam., shorter than calyx. Fl. May-Jun.

* Mixed forests, streamsides; 2100--2600 m. S Yunnan (Jinghong Xian)