Description from Flora of China
Plants annual, 30-60 cm tall, glabrous. Stem erect, terete, few branched. Leaves alternate; petiole 1-3.5 cm; leaf blade pale green abaxially, dark green adaxially, elliptic or lanceolate-elliptic, 5-14 × 2-5 cm, with bristles between teeth, lateral veins 5 or 6 pairs, base cuneate, margin crenate, teeth mucronulate, apex caudate-acuminate. Inflorescences terminal or axillary, racemose, 3-6-flowered; peduncles 3-8 cm, slender. Pedicels 1-5 mm, slender, 1-bracteate at base; bract caducous, ovate-lanceolate, ca. 4 mm. Flowers yellow. Lateral sepals 2, elliptic, ca. 5.5 mm. Lower sepal saccate, constricted into an erect or incurved spur ca. 2.2 cm. Upper petal obovate, ca. 6.5 mm, apex obtuse, mucronulate; lateral united petals not clawed, subovate, 9-17 mm, unequally 2-lobed; basal lobes broadly ovate, short; distal lobes oblong. Filaments compressed, 4-5.5 mm; anthers obtuse. Ovary linear, ca. 5 mm. Capsule elongate, 2-2.5 cm. Seeds many, oblong, ca. 3 mm, granulose. Fl. and fr. Jul.
● Forest understories, shaded places at mountain summits; 2000-2100 m. Taiwan.