Annuals 45-70 cm tall. Roots stout, fibrous. Stems erect, simple. Basal leaves with petiole flattened, 3-3.5 cm; leaf blade elliptic, 15-19 × 8-10 cm, base cuneate and decurrent into wings of petiole, apex acute; veins distinct, pinnate. Lower stem leaves with petiole to 2 cm; leaf blade elliptic, to 11 × 4 cm; middle to upper leaves sessile, ovate, to 7 × 3 cm, base cordate and subamplexicaul, apex acute, veins distinct. Inflorescences many-flowered thyrses, rounded, lax, spreading, to 45 cm. Flowers 4 or 5merous, nodding. Pedicel 1.6-3 cm, slightly thickened at apex. Calyx tube 2-2.5 mm; lobes spreading, ovate to ovate-triangular, 3-3.5 mm, margin narrowly membranous, apex acute. Corolla pale yellow, with dark spots, 1.5-1.7 cm in diam., tube 3-3.5 mm; lobes narrowly oblong, 1.7-1.9 cm, apex acute. Nectaries 1 per corolla lobe, suborbicular, reduced to a naked gland patch. Filaments slightly flattened, 6-7 mm; anthers yellow, narrowly ellipsoid, ca. 5 mm. Style distinct, ca. 2 mm; stigma lobes capitate. Capsules ellipsoid, 1.7-1.9 cm. Seeds pale yellow, ellipsoid, ca. 0.5 mm; seed coat warty. Fl. and fr. Oct-Dec.

Forest margins; ca. 900 m. N Taiwan [Japan].