Scandent herb. Stem up to 4 m long, with 4 irregularly angled sides, very narrowly sulcate, internodes 10 cm long, 1.7 cm in diameter. Cataphyll 29.5 cm long, soon caducous. LEAVES: Petiole sappy, brittle, sub-terete nevertheless flat adaxially, 35-45 cm long, 1.3 cm wide (halfway), sheathing part 7-10 cm long. Leaf blade upright on the petiole, more or less coriaceous, nevertheless brittle (semi-coriaceous when dry), triangular in outline, lateral margins more or less straight, 34-43 cm long, 17-23 cm wide (at the point 4-6 cm above the insertion of the petiole), more or less sub-cordate, with an open sinus 1.5-3.5 cm deep, apex narrowly acuminate (2-3 cm), both surfaces glossy; adaxially deep green, midrib convex, 0.6 cm wide; lateral veins slender, sulcate, 6-7 on each side, arising at an angle of ca. 55-65º (70º); abaxially veins all prominent. INFLORESCENCES in 6s. Peduncle up to 10 cm long (during anthesis). Spathe 8.5-14.5 cm long (with 0.3 cm long cuspid included), tube scarcely differentiated, externally bright ('laete') green, limb paler, from cream to green. Spadix stipitate, with the stipe 0.5-0.7 cm long, female zone 4-4.3 cm long, male zone 7.8 cm long. Pistillate flowers: ovary 5-7-locular, locules uniovulate. Staminate flowers (5-)4-2-androus.