Usually hemiepiphytic, terrestrial; stem appressed-climbing, gray-green to brown or green, sap sweet-scented, drying blackened, leaf scars conspicuous, 2 cm long, 1.7 cm wide; internodes weakly flattened on one side, two-ribbed, weakly glossy, to 8 cm long, but surely longer than wide and 2.5–3 cm diam. at apex, dark to medium green, soon gray, epidermis brown, flaking, fissured sometimes; roots whitish, few per node; cataphylls 10–20 cm long, bluntly or sharply 2-ribbed or unribbed, sharply D-shaped, somewhat spongy, light to medium green or reddish to brownish, sometimes streaked pinkish, semiglossy, drying brown, persisting semi-intact as pale fibers at upper nodes, disorganized below; petioles (18)29–91 cm long, (2)3–7(8–12) mm diam., sometimes terete, usually D- or U-shaped, spongy or firm, dark green, flattened or somewhat sulcate to convex, often with medial rib, margins raised adaxially, rounded abaxially, surface semiglossy, minutely and short-lineate; blades triangular-ovate, more or less subcoriaceous, moderately bicolorous, long acuminate at apex, deeply cordate at base, 25–74 cm long, 18–34 cm wide (1.1–2.8 times longer than wide), (0.5–2 times longer than petiole), broadest more or less near the middle, upper surface dark green, drying blackish, semiglossy, lower surface pale green to yellow-greenish, drying blackish, glossy to semiglossy or matte; anterior lobe 18–58 cm long, 10.1–40.4 cm wide (1.7–4.3 times longer than posterior lobes); posterior lobes 8–17 cm long, (3.7)5–17 cm wide, obtuse to rounded; midrib broadly sunken to broadly convex or flat, dark green, above, raised to narrowly convex, thicker than broad, concolorous or darker than surface below; basal veins 5–10 per side, in part coalesced to 4 cm, barely naked or naked to 2 cm; primary lateral veins 7–11 per side, departing midrib at a 50–60 degree angle, more or less straight to the margins, obtusely to weakly or narrowly sunken and sometimes weakly quilted above, convex and darker than surface below; interprimary veins almost as prominent as primary later veins; minor veins in part discontinuous and darker than surface below, arising from both the midrib and primary lateral veins. Inflorescences erect, 2–6 per axil; peduncle 3–13 cm long (to 20 cm long in South America), 2–6 mm diam., pale green to whitish, with raised, prominent white striations; spathe semiglossy, 6–14.5 cm long, (0.9–3 times longer than peduncle), sometimes greenish with short white lineations throughout; spathe blade white to pale green (at anthesis), reddish (post-anthesis) (B & K red-purple 7.5/7), short-lineate outside, (opening 4.6 cm long, 3.6 cm wide), very pale green to white, matte, few, sparse, dark-lineate inside; spathe tube semiglossy and greenish to greenish brown or reddish (maroon or reddish at anthesis) outside, green to white inside; spadix weakly exserted from the spathe, 7.6–9.2 cm long, constricted near base of fertile staminate portion; pistillate portion pale green or whitish, cylindrical, 1.4–2.4 cm long, 1 cm diam. at apex, 1.1 cm diam. at middle; staminate portion 5.3–7.6 cm long; fertile staminate portion creamy white, cylindrical to weakly tapered, 0.85–1.5 cm diam. at base, 0.7–1.3 cm diam. at middle, 6–10 mm diam. ca. 1 cm from apex, broadest at the base, narrower than the pistillate portion, narrower than the sterile portion; sterile staminate portion broader than the apical area of the pistillate portion, gray-white, 1.1–1.5 cm diam.; pistils 1.8–2.5 mm long, 1 1.4 mm diam.; ovary 4–6(5–7)-locular; locules 1.3–1.7 mm long, 0.5–0.7 mm diam., with axile placentation; ovules 18–26(23–28) per locule, arranged in series of 2, 0.2–0.4 mm long, longer than funicle; funicle 0.1–0.2 mm long, adnate to lower part of partition, style 0.2–0.3 mm long, 1–1.4 mm diam., similar to style type B; style apex flat to slightly rounded; stigma subdiscoid, brushlike, unlobed, 1–1.3 mm diam., 0.2–0.6 mm high, covering entire style apex; the androecium truncate, margins 4–6-sided; thecae oblong to obovate, 0.3–0.5 mm wide, more or less parallel to one another, contiguous; sterile staminate flowers blunt, 1.6–1.8 mm long, 1.4–1.5 mm wide. Infructescence with berries white (mature), 6 mm long, 2.6 mm diam.; seeds 14–16(24–28) per locule, 1.3–1.7 mm long, 0.2–0.3 mm diam. Juvenile plants with internodes 8 cm long, 5 mm diam.; petioles sharply U-shaped in cross-section, usually lacking medial rib adaxially, margins erect.

Type: Mexico. Chiapas: Cerro de Madrugal, along Teapa-﷓Tacotalpa (Tabasco) Highway, at Km 4, W of hwy.,on rock face of steep slopes, Bunting 1526 (holotype, US).

Esmeraldas: Noreste de Las Golondrinas. Cooperativa 3 de Septiembre en sector San Isidro cerca a Río Jordán, 300 m, 0°20'N, 79°12'W, Palacios 11498 (MO, QCNE); Fila de Bilsa, 7 km E of San Jose de Bilsa, ca. 80 km due SW of Esmeraldas, 12 km SE of El Salto on Atacames-Muisne Road, 280 m, 0°37'N, 79°51'W, Gentry & Josse 72923 (MO). Imbabura: Rio Mira valley, 2.5 km E of Lita, 750–775 m, Croat 38983 (MO); Entre El Pajón y Gachaco, 600 m,, Solís 12717 (F). Pichincha: Tinalandia (property of Hotel Tinalandai) 9.6 km E of Santo Domingo de los Colorados, S of hwy. to Aloag & Quito, above Río Toachi, 700 m, 0°16'N, 79°7'W, Croat 55737 (MO, QCA); E side of Río Lelia, ca. 16 km SE of Santo Domingo de los Colorados, 800 m, 0°18.5'S, 79°2'W, Grayum & Zamora 9431 (MO, QCNE).