Stem scandent. LEAVES: Petiole semi-terete, flattened above, ca. 20 cm or longer, 6-8 mm thick, attenuating upwards, with a somewhat thickened geniculum 1.8-2 cm long, glabrous below, rather scabrous above. Leaf blade thinly coriaceous, glabrous on both sides, cordate-ovate, 35-50 cm long in total, up to 40 cm wide; posterior lobes sub-ovate, retrorse, separated by a wide, obtuse rounded sinus; anterior lobe ovate- sub-triangular, apex acuminate, ca. 2 times longer than the posterior lobes; primary lateral veins 3-4 on both sides of the posterior lobes, joined together into a short posterior rib, naked for 1-2 cm in the sinus; 5-6 arcuate-ascending veins on each side of the midrib in the anterior lobe. INFLORESCENCE: Peduncle short, 10-14 cm long, rather densely scabrous. Spathe smooth, oblong, apex rather long- and slenderly-acuminate, ca. 15 cm long, convolute 3-3.2 cm in diameter. Spadix sub-sessile; female zone cylindric, ca. 4 cm long, 7-8 mm thick; male zone narrowly conoid, attenuating upwards, rather obtuse, ca. 2 times longer than the female zone. Pistils shortly oblong obtuse, measuring 1-2 mm, with a small many-lobuled stigma. Male flowers 3-4-androus.