Usually a hemiepiphytic vine or sometimes on rocks; stem appressed-climbing, green as juvenile, graying with maturity, minutely and densely striate, sap watery, unscented, leaf scars conspicuous, 8--10 mm long, 7--9 mm wide; internodes smooth, semiglossy, to 2.5 cm long, 4--10 mm diam., usually longer than broad, medium green to olive-green, epidermis thin, tan, peeling; roots olive green, smooth, few per node; cataphylls thin, semispongy, to 10 cm long, unribbed, bluntly or sharply 1-ribbed, green, drying pale yellow-green, deciduous. LEAVES erect to spreading; petioles 21--57 cm long, (2)3--9 mm diam., terete, moderately spongy, whitish toward apex, slightly flattened toward apex adaxially, surface dark green striate at base; blades triangular in outline, deeply 3-lobed, subcoriaceous, moderately bicolorous, long-acuminate at apex (the acumen apiculate, to 3 mm long), hastate at base, 20--35 cm long, 20--42 cm wide (0.8--1 times longer than wide), (0.6--1 times the petiole length), upper surface dark green, semiglossy to glossy, drying dark brown to dark gray-green, lower surface semiglossy, paler, drying yellow-brown to yellow-green; anterior lobe oblong-lanceolate to oblanceolate, almost elliptic, 16--30 cm long, 7--15 cm wide (1--1.3(1.5)) times longer than lateral lobes); lateral lobes broadly confluent 1--3(8) cm with medial lobe, 10--25 cm long, 3--8.7 cm wide, directed outward (90º angle from midrib), acute to bluntly acute; sinus arcuate; midrib more or less flat to sunken, paler than surface above, broadly convex below; basal veins 4--7 per side, sometimes with last vein free to base, most veins coalesced 1.5--13 cm, 2 veins coalesced to 17 cm, drying reddish brown to yellowish brown; posterior rib naked; primary lateral veins 4--5 per side, departing midrib at a 50--60º angle, narrowly sunken above, convex below; interprimary veins weakly sunken and concolorous above, weakly raised and darker than surface below; tertiary veins visible, darker than surface below; minor veins fine, close, weakly visible to distinct below, arising from both the midrib and primary lateral veins but mostly from the midrib. INFLORESCENCES erect-spreading, 1 per axil; peduncle 5.5--19.5 cm long, 3--8 mm diam.; spathe 7.4--16.6 cm long, (0.8--1.4(1.7) times longer than peduncle); spathe blade green to greenish white to creamy yellow, tinged with violet-purple outside, tinged with violet purple, at least sometimes with yellowish resin canals visible inside; spathe tube green outside, 4--6 cm long, 2--3.5 cm diam., dark violet-purple inside; spadix sessile; white, drying golden-yellow throughout, tapered, more or less rounded at apex, 7.5--10.8 cm long, broadest near the base; pistillate portion pale green (post-anthesis), ellipsoid, 3.6 cm long, 1.3 cm diam. at apex, 1.2 cm diam. at middle, 6 mm wide at base; staminate portion to 8.4 cm long; fertile staminate portion white, ellipsoid, tapered at apex, 8 mm diam. at base, 5 mm diam. at middle, 5 mm diam. ca. 1 cm from apex, broadest at base, much narrower than the pistillate portion; sterile staminate portion tannish, 8 mm diam.; pistils (1.5)2.9--4.4 mm long, 1.7--2.3 mm diam., ovary (6)7--8-locular, (1)2.2--3.2 mm long, ovule sac 0.7 mm long, with sub-basal placentation; ovules 3 per locule, contained within translucent, gelatinous ovule sac, ca. 0.4 mm long, longer than funicle; funicle 0.2--0.3 mm long, (can be pulled free to base), style similar to style type B; style apex flat; stigma discoid, 5--6 mm diam., 0.1 mm high, covering center of style apex; the androecium more or less prismatic, margins irregularly 4--6-sided, 0.7-1.1 mm long; thecae oblong, 0.3 mm wide, more or less divaricate; sterile staminate flowers irregularly 5--6-sided, 1 mm wide. INFRUCTESCENCE 9.5-16 cm long, peduncle to 14 cm long; spadix to 5.3 cm long, to 3 cm wide; berries orange, rhomboid; seeds 1--2(3) per locule, (16)21--22(29) per berry, light brown, 1.5--2 mm long, 0.5 mm diam., with weak constriction (nipple) opposite funicular end of seed.
Mexico to Costa Rica. In Mexico, the species ranges from Nayarit to Oaxaca and Chiapas mostly along the Pacific coast but also occurs in Puebla (Ajenjibre) and Morelos (Cuernavaca). One collection, Moore & Bunting 8874, from near Córdoba in Veracruz state appears out of range for the species. Collections from Guatemala are few, but all are from the Pacific slope except one collection from Baja Verapaz between El Chol and Rabinal (Croat & Hannon 63670). In Honduras and Costa Rica, the species is nearly restricted to the Pacific slope.