Hemiepiphytic; internodes to 7 cm or more long, ca. 1.5 cm diam., usually longer than broad, drying light brown, semiglossy, weakly and irregularly ribbed; cataphylls deciduous; LEAVES: petioles 34 cm long (slightly longer than blades), 7 mm diam., subterete; blades narrowly ovate-cordate, acuminate and slightly inequilateral at apex, sagittate at base, 37 cm long, 20 cm wide (1.8 times longer than wide; about equal in length to petiole), semiglossy, upper surface drying dark olive-green, lower surface drying yellowish brown; anterior lobe 31.5 cm long, 21 cm wide (4 times longer than posterior lobes); posterior lobes 7.5 cm long, 8.7 cm wide, narrowly rounded, directed toward base; sinus more or less V-shaped, 5--6 cm deep; midrib drying narrowly raised and darker below; basal veins 3--4 per side, with 0 free to base, 1 pair coalesced for 2.8 cm; posterior rib to 3 cm long, not naked; primary lateral veins 5--6 per side, arising initially at an acute angle then forming a gradual arch to margin, departing midrib at a 55º angle toward apex, 60--70º angle midway, to 80º angle near the base, weakly arcuate to the margins, drying weakly raised and paler below; minor veins arising from both the midrib and primary lateral veins. INFLORESCENCES 1 per axil; peduncle 6 cm long, 6 mm diam.; spathe 10.5 cm long, (1.75 times longer than peduncle), slightly constricted midway, densely speckled-lineate, especially on the tube, red within, darker red on the tube within, weakly acuminate at apex, convolute to half its length at base; spathe blade greenish white to white, paler along the margins outside; spathe tube medium green outside, 5 cm long; spadix sessile; 6.5--8 cm long, broadest above the middle; pistillate portion 2.9 cm long, 1.7--1.9 cm diam., broadest at the middle; staminate portion 7.2 cm long; fertile staminate portion to 2.2 cm diam. midway, usually broader than the pistillate portion; sterile staminate portion 1.7 cm diam.; pistils 3.3--3.8 mm long, 1.7--1.8 mm diam.; ovary 5--6-locular, with axile placentation; ovules 20 per locule, 0.3--0.4 mm long, equal in length or slightly longer than funicle; style similar to style type B, 1.3--1.5 mm diam.; style apex truncate, minutely warty, irregularly 3--5-sided; stigma 2.3--2.5 mm diam., depressed with 5--6 small stylar canals; sterile staminate flowers 2.7--3.1 mm long, 0.9--1.6 mm wide.