Stem scandent, high up, rooting at the internodes and reddish green, 3-8 cm long, 1 cm thick. Cataphylls fleshy, reddish, acutely 2-keeled dorsally, 7-10 cm long. LEAVES: Petiole flattened on the upper surface, especially towards the apex, terete below, 15-25 cm long, 7-10 mm thick; blade herbaceous, elongate ovate-triangular sagittate, 15-25 cm long, 12-18 cm wide, posterior lobes semiorbicular or semiovate, separated by a subtriangular or parabolic sinus; anterior lobe triangular, narrowing gradually towards the apex, the apex itself suddenly contracted, somewhat cuspidate-acuminate, 4 times longer than the posterior lobes; 4 basal primary lateral joined into short posterior ribs, 4 veins from the midrib spreading at an obtuse angle, secondary veins numerous, oblique between the primary veins. INFLORESCENCE: Peduncle 6-7 cm long. Spathe dark purplish externally, internally crimson, cucullate-boatshaped; tube ovoid, 7-8 cm long, blade shortly ovate, 7 cm long, 4-5 cm wide, apiculate for 5 mm. Spadix subtended by a 3 mm long stipe, female zone 5 mm long, 1.5 mm thick, male zone 10 cm long, thickened above the somewhat constricted base. Pistil obovoid, 8-locular, style discoid, measuring ca. 1.5 mm. Male flowers usually triandrous.