Plants dioecious. Rhizome lying underground or half underground, dark brown outside, purplish in section, thickly cylindric, 7-18 × 4-6 cm. Leaves usually 2; petiole green or purplish green, to 60 cm, proximal 20-30 cm sheathing into pseudostem, encircled by several cataphylls; leaf blade green, 3-foliolate; central leaflet with petiolule 1-4 cm, blade elliptic to ovate, to 30 × 17 cm, base rounded; lateral leaflets similarly petiolulate, obliquely ovate, apex acuminate. Peduncle colored as petiole, 7-12 cm. Spathe green, without stripes, semitranslucent; tube narrowly funnelform, 4-7 cm, throat 2-3 cm in diam.; limb deltoid-ovate, to 7 × 5 cm, apex acute and cuspidate. Spadix bisexual when mature; appendix basically green, 4-6 cm, slender, covered with rather numerous filiform neuter flowers, brushlike. Berries reddish, ovoid, ca. 5 mm in diam. Fl. Jun-Jul, fr. Oct-Nov.