Arisaema wattii Hook.f.

Plants dioecious. Tuber depressed globose, 2.3–5cm in diam. Cataphylls 3 or 4, green or violet, with purplish spots, 15–20cm, apex acute or obtuse. Leaves 2; petiole yellow-green with dark brown spots consisting of tiny striae, finally to 60cm, proximal 1/3–1/2 forming pseudostem; leaf blade 3-foliolate; leaflets sessile, green; central leaflet elliptic, 15–30 × 4–10cm, base cuneate, apex acuminate; lateral leaflets narrowly obovate, oblique, as long as central one, base auriculate, rounded on outer side, narrowly cuneate on inner side. Inflorescence emerging before leaves; peduncle as long as petioles. Spathe purplish brown or purplish green, 11–13cm in total; tube cylindric, 4.5–6.5 × 1–2cm, throat margins with horizontal auricle 1.5–2.5cm wide; limb broadly ovate, 6–7 × 3.5–5cm, base slightly constricted, apex shortly acuminate. Spadix unisexual; female zone conic, 1.5–2 × ca. 1cm; ovary obovoid; ovules 4, basal; style short; stigma disciform; male zone 1.5–3cm; synandria lax; anthers 2, shortly stipitate, purple, dehiscing by apical pore. Appendix erect, whitish green, cylindric, 2.5–4.5cm × 4.5–5mm, base truncate with a stipe 5–7mm, middle part slightly constricted, apex obtuse. Berries red. Seeds 4, ovoid.