Description from Flora of China
Herbs to 1 m tall, erect. Stems 4-angled when young then subterete, subglabrous. Petiole 2-5 cm, subglabrous; leaf blade elliptic to broadly elliptic, 13-15 × 6-8 cm, cystoliths white, abaxially glabrous or puberulent along veins, adaxially glabrous, secondary veins 9 or 10 on each side of midvein and netted near margin, base broadly cuneate, margin slightly undulate, apex cuspidate. Spikes terminal, ca. 9 cm, 1-sided; peduncle ca. 1 cm; bracts 4-ranked, each 2 sterile or fertile, oblong to elliptic-oblong, ca. 15 × 4-5 mm, homomorphic, glabrous, margin narrowly hyaline, apex acute. Calyx ca. 5 mm; lobes linear. Corolla not seen. Capsule ca. 1.2 cm, glabrous. Seeds blackish brown, ovate in outline, densely verrucose. Fr. Apr-Jun.
● Streamsides; 900-1900 m. Yunnan.