Plants to 2.5 m tall. Rhizome long-creeping, 1.5–2 cm diameter; nodes of stem purplish. Leaves: sheaths diverging from the rachis; lamina narrowly ovate to narrowly elliptic, (17–)24–55(–75) by 4–15(–20) cm, base gradually narrowed into the sheath, apex acute, lower side glaucous. Inflorescence unbranched, with 2‑flowered cincinni; pedicels 1–2 cm long, to 3 cm in fruit; primary bracts 9–20 cm long, acute; branch bracts 1–3 cm long, obtuse; floral bracts (broadly) obovate-elliptic, 0.6–1 cm long, obtuse, caducous; bracteoles (broadly) obovate-elliptic, 0.3–0.4 cm long, obtuse; bracts, bracteoles, and sepals often glaucous. Flowers yellow, erect, 3–4 cm long; sepals green, narrowly obovate-elliptic, 0.5–0.8(–1.5) by 0.2–0.3 cm, obtuse; corolla (greenish) yellow, 3–5 cm long, petals reflexed, narrowly triangular-ovate, 2–3.5 by 0.3–0.6 cm, acute; staminodes 4, golden yellow, 4–4.5 cm long, free part narrowly elliptic to narrowly obovate, 1.5–3.5 by 0.5–1 cm, patent, 1 recurved and sometimes dotted with purple; stamen yellow, free part narrowly elliptic-ovate, 1.5–3 by 0.3–0.4 cm, theca 0.5–1 cm long; style yellow, free part narrowly obovate to linear, 2–3.5 by 0.2–0.3 cm. Fruit green, ovoid, obovoid to narrowly ellipsoid when young, size of ripe fruit unknown. Seeds broadly ellipsoid, c. 5 by 3 mm.