Hemiepiphytic; stem appressed-climbing, scandent; leaf scars inconspicuous; internodes short, thick, 1.5-2.5 cm long, 2-7 cm diam., broader than long, drying yellow-brown, epidermis moderately glossy, finely and acutely ridged on younger stems, lighter and more matte on older stems; roots drying brown, 15-75 cm long, 1-5 mm diam., numerous per node, epidermis peeling; cataphylls drying chartaceous, 7-25 cm long, usually 1-ribbed, pale red to reddish brown, drying yellowish brown to dark brown, persisting semi-intact as fibers. LEAVES erect to erect-spreading; petioles 53-109 cm long, 8-20 mm diam., sharply D-shaped, with broad medial rib adaxially, surface sometimes densely short-lineate, drying smooth and matte to semiglossy, light reddish brown or dark yellow-brown, the epidermis smooth and often flaking; blades ovate-triangular, moderately bicolorous to concolorous, abruptly acuminate at apex (the acumen (1)1.7-2.5 cm long), cordate at base, 56-84.5 cm long, 22-47 cm wide (1.8-2.7 times longer than wide), (0.77-1.1 times longer than petiole), broadest below point of petiole attachment margins broadly undulate, occasionally downturned, upper surface dark green, glossy to semiglossy, drying reddish brown, gray-green or olive-green, matte to weakly semiglossy, lower surface drying semiglossy, yellow-brown to reddish yellow-green; anterior lobe 32-64 cm long, 20-46 cm wide (2.6-3.3 times longer than posterior lobes), broadest at or near base, margins concave; posterior lobes 14.5-21.5 cm long, 22-47 cm wide, broadest at or near base, directed downward and inward to downward and outward, obtuse to semirounded; sinus spathulate to widely hippocrepiform; midrib weakly raised to flat above, thicker than broad, paler than surface, drying concolorous or darker than surface below; basal veins 6-10(15) per side, with 1 free to base, numbers 4-7 coalesced 6-9 cm, prominently raised below; posterior rib naked for 3.5-4 cm; primary lateral veins 11-16 per side, departing midrib at a 55-90º angle, straight to weakly arcuate, drying reddish brown, sunken and paler than surface above, raised, drying slightly darker than surface below; interprimary veins as conspicuous as primary lateral veins; minor veins arising from both the midrib and primary lateral veins; lesser veins drying prominulous; "cross-veins" moderately conspicuous on both surfaces. INFLORESCENCES erect, to 6 per axil; peduncle 7-7.5 cm long, 7-15 mm diam., green, coarsely lineate; spathe coriaceous, 13-18.5 cm long, (1.8-2.6 times longer than peduncle), more or less constricted midway on the tube, acute at apex; spathe blade green, short pale-lineate towards base, striate near apex outside, 10.5 cm long, (opening broadly oblong-ovate in face view; spathe tube oblong-ellipsoid, green, tinged purple-violet, paler along margin outside, 8.5-9 cm long, 3.5 cm diam., maroon, conspicuously short-lineate inside; spadix sessile; oblong, 12.5 cm long, constricted at base of fertile staminate portion and tapering at both ends; pistillate portion white, cylindrical to ellipsoid, 6.5-7.5 cm long, 2.2-2.5 cm diam. throughout; staminate portion creamy white, 9 cm long, 9 mm diam. throughout, broadest in lower one-third; fertile portion 9--11 mm diam.; sterile portion narrower than the pistillate portion, 9-15 mm diam.; pistils 1.9-2.3 mm long, 1.9-2.3 mm diam.; ovary 3-5-locular, drying irregularly angled, walls embedded with granular, crystal-like particles, with axile placentation; ovules 20-22 per locule, style similar to style type B; style apex broadly and shallowly concave; stigma button-like, 0.5-0.7 mm long; sterile staminate flowers 2-2.4 mm long, 1-1.5 mm wide. INFRUCTESCENCE with berries white; seeds 0.8-0.9 mm long, 0.3-0.4 mm diam.