Plants dioecious. Tuber depressed globose, 2-4.5 cm in diam., with many fimbriate roots. Cataphylls 1 or 2, whitish green, flushed purplish, 17-36 × 1-1.5 cm, membranous, apex acute, sometimes obtuse. Leaf solitary; petiole dark green, unmarked, 17-55 cm, smooth, base forming pseudostem; leaf blade 3-foliolate; leaflets pale green abaxially, green adaxially, margin crisped or shallowly crenulate, petiolulate; central leaflet with petiolule 1-3 cm, blade obovate to obcordate, ca. 16 × 20 cm, apex depressed or concave with a short mucro; lateral leaflets with petiolule winged and 1-2 cm, blade broadly rhombic or obliquely ovate, 19-26 × 15-20 cm, base obliquely rounded or truncate, decurrent to petiolule, apex abruptly acuminate or acute, sometimes with filiform tail ca. 1.5 cm. Peduncle whitish green to dark green, unmarked, much shorter than petioles, emerging from pseudostem, 15-20 cm, smooth. Spathe green, purple, or dark green with broad white stripes; tube funnelform, 5-6 cm, ca. 2 cm in diam. at base, ca. 4 cm in diam. at throat, not auriculate; limb slightly incurved or suberect, oblong, ca. 15 × 4-6 cm, apex acuminate, sometimes with a filiform tail 2-3 cm. Spadix unisexual; female zone 3-4.5 cm; ovaries dense; stigma subsessile; male zone cylindric, 3.4-4 × 1-1.5 cm; synandria with stipe 2-3 mm; anthers usually 4, globose, each dehiscing by horseshoe-shaped slit. Appendix whitish, narrowly conic, basal 4-6 cm densely papillose or rugose, ca. 1.5 cm in diam., abruptly narrowed at base into stipe ca. 6 × 5 mm, distal part smooth and gradually drawn into flagellum to 38 cm in total, exserted from spathe tube and tortuous, pendulous in distal flagellate part. Fl. May-Jun.