Stem scandent, internodes elongated up to 2 cm thick. LEAF petioles sheathed almost up to lower third, thereafter moderately terete, 25 cm long; blade herbaceous cordate-triangular, ca. 55 cm long, 35 cm wide. Posterior lobes semi-elliptic, rounded, separated by an almost rectangular sinus. Anterior lobe margin slightly lobed, with apex narrowly acuminate, thin, ca. 2.5 cm long. Posterior lobes with 5 primary lateral veins joined into a short posterior rib, not denuded in the sinus. One primary lateral vein spreading between each lobe, anterior lobe with 5-6 spreading at an obtuse angle from the midrib, strongly prominent below. INFLORESCENCE: Peduncle almost 10 cm long, 1.2 cm thick. Spathe green oblong-apiculate, slightly constricted halfway, ca. 18 cm long, convolute, almost 4 cm diam. Spadix subtended by a stipe almost 1 cm long; Female zone 6 cm long, 1-1.2 cm thick halfway, male zone cylindroid obtuse 8-9 cm long, with a short sterile part, a little narrow than the lower female part, upwards gradually attenuate. Pistils broadly conoid, ca. 2 mm long, 5-locular, stigma moderately large, discoid coronate. Male flowers usually tetrandrous.