Usually epiphytic, sometimes hemiepiphytic (often occuring high in canopy), rarely terrestrial (accidentally); stem usually appressed-climbing, creeping, brownish, sap sweet, turpentine- to burseraceous-scented; internodes weakly glossy, minutely striate longitudinally, 2--3 cm long, 1.5--3.5 cm diam., usually broader than long, dark to medium green, drying brown, epidermis fissured longitudinally; roots moderately few, drying reddish brown; cataphylls sharply 2-ribbed, D-shaped, deciduous, margins sharply raised. LEAVES erect-spreading to spreading; petioles 33.5--66 cm long, more or less terete, somewhat spongy, dark green, obtusely to weakly flattened adaxially, surface weakly glossy, not noticeably marked, drying 8--15 mm diam., usually greenish dark brown; blades ovate-cordate, subcoriaceous, glossy, weakly bicolorous, acuminate to long-acuminate at apex (the acumen inrolled, 7--11 mm long), cordate at base, 35--55 cm long, 17--26 cm wide (2.1 times longer than wide), (0.8--1 time longer than petiole), margins weakly undulate; upper surface dark green, semiglossy, drying gray-green, lower surface glossy to semiglossy, paler, drying green to brownish green; anterior lobe 30.5--41 cm long, 16--26 cm wide (2.6--2.9 times longer than posterior lobes); posterior lobes 10.5--15.8 cm long, 7--13 cm wide, rounded at apex; sinus spathulate, 12 cm deep; midrib flattened, slightly paler than surface above, raised to convex, paler than surface below; basal veins 5--6 per side, with none or rarely 1 free to base, two to three veins coalesced 2.7--5.5(6.3) cm; posterior rib naked for 4 cm; primary lateral veins 5--7 per side, departing midrib at a 70--80º angle, straight to the margins, weakly and narrowly sunken above, convex and paler than surface below; minor veins moderately obsure to clearly visible below, arising from both the midrib and primary lateral veins. INFLORESCENCES 1 per axil; peduncle 4.5--9.4 cm long, 0.08--0.15 cm diam., green, weakly striate; spathe semiglossy, 15--20 cm long, (2.1--3.3 times longer than peduncle), constricted above the tube, dark green throughout, pale maroon to white inside; spathe tube oblong-ellipsoid, weakly wrinkled longitudinally outside, 6--9 cm long, dark maroon, suffused onto blade inside; spadix sessile; greenish white to white throughout, oblong, 12--16.9 cm long; pistillate portion creamy white to pale green, cylindrical, 5--13 cm long, 6--12 mm diam. at apex, 12 mm diam. at middle, 5--10 mm wide at base; staminate portion 7--11 cm long; fertile staminate portion white, ellipsoid, 1 cm diam. at base, 1.4 cm diam. at middle, 6 mm diam. ca. 1 cm from apex, broadest at the middle, slightly broader than the pistillate portion, narrower than the sterile portion; sterile staminate portion broader than the pistillate portion, white, 1.5 cm diam.; pistils 3 mm long, 1.1--1.3 mm diam., ovary 9--10(11)-locular, 1.8 mm long, 1.2 mm diam., with sub-basal placentation; ovules 2--3 per locule, contained within translucent or transparent ovule sac, 0.3 mm long, more or less equal in length to funicle, style similar to style type B; style crown about as broad as ovary; central style dome well developed; style apex with central domes; stigma discoid, weakly lobed, 1.1 mm diam., 0.2--0.3 mm high, covering entire style apex, depressed medially; the androecium margins mostly 5-sided, sometimes 4--6-sided; thecae oblong to ovate, 0.4 mm wide.