Shrubs or small trees, 1-3 m tall. Roots stout, multibranched, outside yellowish. Branchlets gray-green, densely explanate, pubescent. Petiole 9-14 mm, pubescent, sulcate adaxially; leaf blade green, lanceolate to elliptic-lanceolate, 8-17(-20) × 4-6.5 cm, membranous, both surfaces pubescent, midvein raised abaxially, impressed adaxially, lateral veins 8 or 9 pairs, raised abaxially, anastomosing near margin, reticulate veins distinct, base cuneate to obtuse, margin entire, apex acuminate. Racemes terminal or axillary, 10-15 cm, pubescent; bracteoles caducous, basal, linear-oblong. Sepals 5, ciliate, caducous after anthesis; outer sepals 3, small, unequal, upper one helmet-shaped, 6-7 mm, other 2 ovate to elliptic, ca. 3 mm; inner sepals 2, petaloid, obliquely obovate, large, ca. 1.5 × 0.7-0.8 cm, base attenuate, apex rounded. Petals 3, connate in lower 2/3, yellow; lateral petals oblong, ca. 1 cm, inside glabrous at base, apex nearly truncate; keel hooded, ca. 1.2 cm, apex with fimbriate appendages, with stalk ca. 3 mm. Stamens 8, 1-1.1 cm, lower 2/3 united forming an open staminal sheath; anthers ovoid. Disk annular. Ovary globose, compressed, 3-4 mm in diam., ciliate; style 8-9 mm, thin, apex tubiform, shallowly 2-lobed; stigma with short stalk. Capsule green-yellow, broadly obcordate to orbicular or obovoid, 1-1.4 cm in diam., not winged and eciliate; carpels with concentric circles costate. Seeds 2, brown-black, globose, ca. 4 mm in diam., densely white pubescent; strophiole hooded, apex convex. Fl. May-Aug, fr. Aug-Oct.