Terrestrial or hemiepiphytic; stem appressed-climbing, 2--3 m long, thick, leaf scars conspicuous, 1.2--1.7 cm long, 2--2.5 cm wide; internodes smooth, to weakly pruinose, 3--6 cm long, 4--7 cm diam., about as long as broad, green to olive-green, epidermis drying smooth, semiglossy, light yellow-brown (B & K Yellow-Red 9/10), cracking with age, fissured transversely, sometimes with minute cracks perpendicular to axis; roots few per node, elongate, to 4 mm diam., light brown, smooth, weakly glossy, the epidermis cracking free upon drying; cataphylls thick, 18--32 cm long, sharply 2-ribbed (ribs 4 mm high), pale green, glaucous, dark short-lineate, deciduous. LEAVES erect-spreading, clustered at or near stem apex; petioles 49--70 cm long, 1.2--2.5 cm diam., more or less D-shaped, becoming flattened and much broader than thick toward apex, medium green, rounded to flattened abaxially, with adaxial margins prominently winged (to 3 mm diam.), undulate to broadly flattened, surface dark short-lineate, glaucous; blades ovate-cordate to oblong-ovate cordate, moderately coriaceous to subcoriaceous, gradually acuminate to abruptly acuminate at apex, cordate at base, 36--60 cm long, 22--44 cm wide (1.3--1.8 times longer than wide), (0.85--0.88 times the petiole length), broadest slightly above point of point of petiole attachment, margins moderately undulate, upper surface medium green, semiglossy, drying greenish yellow, lower surface medium to pale green, glaucous, matte, paler, drying greenish yellow; anterior lobe 28--44 cm long, 10--20 cm wide, (0.9--1.3 times longer than wide), (1.8--2.9 times longer than posterior lobes), broadest at base; posterior lobes usually overlapping, 10--20 cm long, 10--20 cm wide, directed downward and slightly inward, obtuse to rounded; sinus oblong-triangular or closed, 10--19 cm deep; midrib flat to weakly raised, pale green, concolorous above, weakly raised, paler than surface below; basal veins 5--10 per side, 1--2 pairs free to base, the remainder mostly free, sometimes weakly coalesced 1--4 cm, drying weakly raised; posterior rib usually not present, naked and straight if present; primary lateral veins 7--11(15) per side, departing midrib at a 30--45º angle, straight or slightly arcuate to the margins, flat to sunken and drying darker than surface above, convex and darker than surface below; interprimary veins prominulous, weakly sunken to flat, concolorous above, flat and darker than surface below; lesser veins visible when dried; minor veins conspicuous, fine, darker than surface below, arising from both the midrib and primary lateral veins. INFLORESCENCES 4 per axil; peduncle 7.7--8 cm long, 8 mm diam., medium green; spathe more or less erect, 20--21 cm long (2.5--2.7 times longer than peduncle), medium green throughout, glaucous, more or less acute at apex; spathe tube maroon, suffused maroon onto blade inside; spadix sessile; tapered, 20--21 cm long; pistillate portion tapered toward the apex, 5.2 cm long, 1.3 cm diam. at apex, 1.5 cm diam. at middle, 1.7 cm wide at base; staminate portion 14.7 cm long; fertile staminate portion tapered, 1.4 cm diam. at base, 1.3 cm diam. at middle, 1.1 cm diam. ca. 1 cm from apex, broadest at the base, narrower than the pistillate portion, narrower than the sterile portion; sterile staminate portion narrower than the pistillate portion, 1.4 cm diam.; pistils 4.5 mm long, 2.1--2.4 mm diam.; ovary 7--8-locular, locules 1.9 mm long, with sub-basal placentation; ovules 9--10 per locule, 0.4--0.5 mm long, slightly longer than funicle, style 2 mm long, 1.8 mm diam., similar to style type B; style apex flat; stigma subdiscoid, unlobed, 2 mm diam., 0.4 mm high, covering entire style apex; the androecium truncate, margins 4--6-sided; thecae oblong, 0.5 mm wide, contiguous; sterile staminate flowers blunt, 3.2 mm long, 1.7 mm wide.