Description from
Flora of China
Annuals 2-15 cm tall. Roots yellow, stout. Stems erect, slender, subquadrangular, narrowly winged on angles, branched. Basal and lower stem leaves short petiolate; leaf blade spatulate to elliptic, 0.7-1.3 cm × 2.5-5 mm including petiole, base narrowed, apex obtuse, midvein prominent. Upper stem leaves sessile, linear to linear-lanceolate, 0.6-1.8 cm × 1-3.5 mm, base narrowed, margin slightly revolute, apex acute, midvein prominent. Inflorescences usually reduced to a single flower. Flowers 5merous. Pedicel erect, 1.2-6 cm, stout. Calyx tube 2-3 mm; lobes linear-lanceolate, 0.8-1.6 cm, equal, base obtuse, slightly revolute, apex acute, midvein prominent. Corolla rose, 2.5-3 cm in diam., tube 2-3 mm; lobes ovate-oblong to elliptic, 1.1-1.7 cm, apex rounded and mucronate. Nectaries 2 per corolla lobe, radially elongated, with a narrow scale, and raised margin with many compound fimbriae. Filaments 6-8 mm; anthers ellipsoid, ca. 2 mm. Ovary elliptic, 5-7 mm. Style ca. 2 mm; stigma lobes capitate. Fl. Aug-Nov.
* Grassland slopes; 1800-2900 m. S Sichuan, Yunnan.