Description from Flora of China
Plants annual, 30-60 cm tall. Stem robust, simple and long naked, or branched; branchlets succulent. Leaves alternate; petiole long, 3-4 cm; leaf blade pale green-gray abaxially, green adaxially, ovate-elliptic or obovate, 3-13 × 3-4.5 cm, membranous, abaxially glabrous, setose between teeth, adaxially strigose, lateral veins 5-7 pairs, base cuneate, attenuate into petiole, margin crenate or crenate-serrate, apex acuminate. Inflorescences in upper leaf axils, 2-flowered; peduncles longer than petioles, 2-3(-4) cm, elongate at fruiting. Pedicels 1-2 cm, bracteate at base (but appearing as if at middle in upper flowers); bracts persistent, green, lanceolate or ovate-lanceolate, 3-5 mm, herbaceous. Flowers yellowish, ca. 3.5 cm deep. Lateral sepals 2, green, ovate or orbicular, 6-10 × 6-8 mm, membranous, 3-5-veined. Lower sepal navicular, limb 1.5-1.8 cm deep, narrowed into an incurved spur; spur orange striate, ca. as long as or longer than limb, slender; mouth vertical, 1.5-2 cm, tip acuminate. Upper petal orbicular, 1.3-1.5 cm, apex cuspidate, abaxial midvein not thickened, narrowly carinate; lateral united petals not clawed, 2-2.5 cm, 2-lobed; basal lobes suborbicular, small; distal lobes dolabriform, larger, apex obtuse-rounded; auricle inflexed, orbicular. Filaments fibrous, 5-6 mm; anthers ovoid, apex obtuse. Ovary linear. Capsule erect, narrowly fusiform, 2-2.5 cm. Seeds many, yellow-brown, oblong, 2-3 mm, smooth. Fl. Jul-Sep, fr. Oct.
● Forest margins, shaded moist places, roadsides; 900-1800 m. Chongqing, Sichuan (Emei Shan, Hongya, Jinyuan Shan).