Herbs perennial. Stems ca. 1 m tall, deeply grooved, densely appressed, tawny stellate tomentose. Petiole 3-6 cm, narrowly winged; leaf blade broadly ovate-elliptic, 18-30 × 7-15 cm, adaxially corrugate and sparsely minutely hispid, abaxially densely gray stellate tomentose, base cuneate-attenuate, decurrent, margin irregularly shallow dentate, apex acuminate. Cymes axillary, dense, many flowered, ca. 5 cm; peduncle 2-5 mm; bracts ovate, 2-2.8 × 0.7-1.4 cm, apically acuminate; bracteoles linear, 1-2.3 cm. Calyx narrowly campanulate, ca. 13 × 4.5 mm, densely gray stellate tomentose; teeth triangular, ca. 1/2 as long as calyx, apically linear, ciliate inside. Corolla yellow, ca. 4.6 cm, puberulent; tube ca. 2 mm in diam., abruptly dilated from apical 1/3 to 1.1-1.3 cm wide at throat; upper lip straight, 6-9 × ca. 8 mm, lower lip ca. 1.3 × 1.3 cm. Fl. Aug.