Description from Flora of China
Plants 4-10(-25) cm tall, glabrous. Stems simple to much branched, obscurely 4angled. Leaves sessile; lower leaves elliptic to ovate-elliptic, 0.6-1.7 cm × 3-6 mm, base rounded, apex obtuse, veins 1-3 and abaxially distinct; upper leaves elliptic-lanceolate, 0.6-2 cm × 2-7 mm, base rounded and nearly clasping, apex acuminate, acute, or mucronate, veins 1-3. Cymes laxly dichotomous or racemose. Pedicel 3-5 mm, slender, 4angled. Calyx lobes subulate or linear-lanceolate, 2.5-3 mm, apex acuminate, midvein distinct or strongly crested. Corolla white, pink, or purple, 1.3-1.5 cm; lobes narrowly oblong, 2.7-3.2 mm, margin entire, apex obtuse. Filaments 1.5-2 mm; anthers ellipsoid, 0.5-0.7 mm.
Style 2-2.5 mm. Capsules ellipsoid, 7.5-9 mm. Seeds blackish, globose, 0.2-0.3 mm in diam. Fl. and fr. May-Jul.
100-2200 m. Fujian, Gansu, Guangdong, Guangxi, Hainan, Hebei, Heilongjiang, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Nei Mongol, Ningxia, Qinghai, Shaanxi, Shandong, Shanxi, Taiwan, Xinjiang, Zhejiang [India, Russia; N Africa, C and W Asia, Europe]