Ophelia bimaculata Siebold & Zuccarini, Abh. Math.-Phys. Cl. Königl. Bayer. Akad. Wiss. 4(3): 159. 1846; Silene esquirolii H. Léveillé; Swertia bimaculata var. macrocarpa Nakai; S. platyphylla Merrill.

Annuals 30-140(-200) cm tall. Roots yellow, fibrous. Stems erect, 2-6 mm in diam., branched. Basal leaves withered at anthesis. Stem leaves sessile or short petiolate; leaf blade broadly elliptic to ovate-lanceolate, 3.5-9 × 1-4(-5) cm, base narrowly tapered to obtuse, apex acuminate; veins 3-5, arcuate. Inflorescences panicles of cymes, lax, spreading branched, many flowered, to 50 cm. Flowers 5merous. Pedicel spreading to erect, 0.6-4 cm, stout, terete. Calyx tube 1-2 mm; lobes narrowly oblanceolate to narrowly elliptic, 3-6 mm, base narrowed, margin slightly revolute and membranous, apex acuminate; veins 3-5, indistinct. Corolla yellow or white, with purple spots, to 2.5 cm in diam., tube 1-2 mm; lobes oblong to elliptic, 1-1.5 cm, base narrowed, apex acuminate to acute. Nectaries 2 per corolla lobe, yellow-green, orbicular, reduced to a naked gland patch without raised margin. Filaments 5-6.5 mm; anthers ellipsoid, ca. 2.5 mm. Style indistinct; stigma lobes capitate. Capsules narrowly ovoid, to 2.3 cm. Seeds brown, globose; seed coat warty. Fl. and fr. Jun-Nov.

Beside streams, swamp, meadows, scrub, forests; 200-3000 m. Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hainan, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Shaanxi, Shanxi, Sichuan, Xizang, Yunnan, Zhejiang [Bhutan, India, Japan, Malaysia, Myanmar, Nepal, Sikkim, Vietnam].