Herbs perennial, glabrous, aromatic when dry. Stems erect, 20--50 cm, quadrangular. Leaves alternate, subsessile; petiole less than 2 mm; leaf blade ovate to ovate-lanceolate, 5--13 X 2--4 cm, base rounded to subcordate, slightly asymmetrical, apex acuminate to long acuminate; veins raised abaxially, slightly impressed adaxially; veinlets prominently reticulate. Racemes terminal and axillary, 4--15-flowered; rachis 5--20 cm; bracts subulate, 2--3 mm. Pedicel 2--3 cm. Calyx lobes ovate-lanceolate, ca. 2 mm, glandular inside. Corolla yellow, deeply parted; lobes reflexed at anthesis, narrowly elliptic, 7--10 X ca. 2 mm. Filaments connate basally into a ring, free parts ca. 1 mm; anthers 4--5 mm, basifixed, opening by apical pores. Style ca. as long as to slightly longer than stamens. Capsule globose, ca. 3 mm in diam. Fl. Jun.

* In caves within calcareous formations. NW Guangxi (Fengshan Xian).