Plants 10-30 cm tall, with a rather short rhizome. Stem erect, slender, glabrous, with 2 or 3 tubular sheaths at base and 2 leaves at apex. Leaves spreading horizontally, opposite or subopposite; blade broadly ovate, triangular-ovate, or cordate, 2.5-7 × 2.5-7 cm, herbaceous, glabrous, minutely ciliate, with 3-5 palmate veins and inconspicuous reticulate veinlets, base subcordate or broadly cuneate, apex acute or shortly acuminate. Inflorescence terminal, pendulous, with 1 flower; peduncle arching, usually 2-5 cm, slender, glabrous; floral bracts linear, 1.5-3 cm, glabrous; pedicel and ovary 8-14 mm, glabrous. Flower small, often hidden under leaves; sepals and petals pale green or yellowish green, with maroon spots or markings at base; lip white with maroon spots inside and sometimes stripes toward its mouth. Dorsal sepal narrowly ovate-lanceolate, 1-2 × 0.5-0.7 cm, glabrous, apex acuminate; synsepal similar to dorsal sepal, often slightly smaller, apex nearly unlobed. Petals lanceolate, 1-2 × 0.3-0.5 cm, apex acute, often ± enfolding lip; lip deeply pouched, subellipsoid, 1-1.5 cm, with a broad mouth, inner bottom hairy. Staminode orbicular to ovate, 1-2 mm. Capsule narrowly ellipsoid, 1-1.8 cm × 5-6 mm. Fl. May-Jul, fr. Aug-Sep. 2n = 20.