形态特征：Herb perennial, 12‒25 cm tall. Roots slender. Stems caespitose, unbranched, erect, green, sparsely to densely white-pubescent. Leaves opposite; basal and lower leaf blades spatulate or narrowly spatulate, 1.2‒3.2 cm long, 0.4‒0.8 cm wide, entire and sparsely ciliate at margin, apex acute, base attenuate, sparsely pubescent on both surfaces; upper leaf blades ovate, ovate-elliptic or oblong, 1.2‒4 cm long, 0.5‒1.5 cm wide, entire and sparsely ciliate at margin, apex acute, base slightly cordate, sparsely pubescent on both surfaces, sessile. Cyme terminal or axillary in upper part of stems, 6‒15-flowered; bracts leaf-like but smaller, narrowly ovate or lanceolate, herbaceous, sparsely pubescent on both surfaces; pedicels slender, 3‒12 mm long, white-pubescent; flowers white, 1.1‒1.3 cm in diam. Sepals 5, lanceolate, green, 5‒6 mm long, apex acuminate, margin membranous, abaxially pilose and glandular-pubescent. Petals 5, narrowly obovate, white, 6‒7 mm long, slightly longer than sepals, 2-lobed for ± 1/4 of length, lobes broadly ovate-oblong, apex acute, base glabrous. Stamens 10, filaments glabrous, slightly shorter than sepals. Styles 5, linear. Capsules cylindric, ± 2 as long as sepals, 10-toothed. Seeds numerous, subtriangular-globose, slightly compressed, brown, ca. 1 mm in diam., tuberculate.
