Plants to 2 m tall. Rhizome long-creeping, 0.2–0.5 cm diameter. Leaves: sheaths more or less lanuginose; lamina narrowly elliptic to narrowly (ob)ovate, 20–55 by 5–18 cm, base gradually and continuously narrowed into the sheath, apex acute or sometimes shortly acuminate, lower side more or less glaucous. Inflorescence unbranched, with 1- (or 2-)flowered cincinni; pedicels up to 0.2 cm long, not lengthened in fruit; primary bracts 10–20 cm long, acute; branch bracts 11–14.5 cm long, acute; floral bracts depressed ovate to ovate-triangular, 0.2–0.5(–1) cm long, obtuse to acute, persistent; bracteoles narrowly triangular, 0.4–3 cm long, acute; bracts, bracteoles, and sepals glaucous. Flowers yellow, erect, 10–14 cm long; sepals pale yellow, narrowly ovateelliptic, 2–3.5 by 0.4–0.8 cm, acute; corolla green, 10–13 cm long, petals reflexed, narrowly ovate-triangular, 4–6.5 by 0.3–1.8 cm, acute; staminodes 4, yellow, 9–14 cm long, free part obovate to broadly obovate, 6–7 by 1.5–6.5 cm, erect, showy, thin and flaccid, margins undulate; stamen yellow, free part obovate, 5.5–7 by 2.5–3.5 cm, theca 1.5–2 cm long; style yellow, free part narrowly obovate, 2.5–4 by 0.8–1.2 cm. Fruit green, maturing dark brown, very densely covered by tubercles, ellipsoid, 3–6 by 2–3.5 cm. Seeds globose, 5–7 mm diameter.