Liana to at least 5 cm in diameter, the bark gray, smooth; stem with 4 phloem arms in cross section; twigs subtetragonal, longitudinally striate, glab- rous to subpuberulous, interpetiolar glands conspicuous; pseudostipules ver- tically 3-seriate, acute. Leaves 3-foliolate or 2-foliolate with a tendril or tendril scar; leaflets ovate, long-acuminate to acute, broadly cuneate to narrowly sub- cordate, membranaceous, secondary nerves 6-10 on a side, scattered lepidote below, less so above, puberulous along main veins above and beneath, sunken plate-shaped glands usually conspicuous on both surfaces, olive to brownish when dry, usually darker above; tendril trifid, 8-16 cm long to branching, the three arms 0.2-4.0 cm long, often unequal; terminal leaflet 9-24 cm long and 3.4-10 cm wide, the laterals 7.8-22 cm long and 2.4-9.2 cm wide; terminal petiolule 1.5-6.1 cm long, the laterals 0.5-3.2 cm long, the petiole 0.9-7.1 cm long, above with a conspicuous apical glandular field, scabrous as the petiolules. Inflorescence a short axillary or terminal raceme of ca. 10 flowers opening one at a time, the rachis and pedicels puberulous. Flowers with the calyx campanu- late, irregularly truncate, puberulous, with scattered glands, 7-12 mm long and 5-9 mm wide; corolla white (Panama), tubular-campanulate, 3.6-7.3 cm long and 0.7-1.4 cm wide at the mouth of tube, the tube 3.0-6.3 cm long with a narrowed base 2.3-2.6 cm long and 0.2-0.6 cm wide, lobes 0.5-1.8 cm long, simple puberulous outside with plate-shaped glands at the base of the lobes, inside glandular-lepidote on the lobes and glandular-pubescent below the level of stamen insertion; stamens didynamous, the anther thecae pubescent, each 2-4 mm long, usually bent, the longer filaments 1.9-2.1 cm long, shorter filaments 1.4-1.6 cm long, the staminode 0.3-9.8 cm long, inserted 2.3-2.5 cm above the base of corolla tube; pistil 4.5-4.8 cm long, ovary flattened-cylindric, 2-3 mm long and 1.5-2 mm wide, 1-1.5 mm thick, minutely papillose; disc pulvinate, 1-2 mm long and 3-4 mm wide. Capsule (Panama) fusiform-oblong, acuminate at both ends, only slightly compressed, 10.2-22 cm long and 2.4-4.0 cm wide, 1.0-2.4 cm thick, the surface smooth, somewhat glandular and slightly lepidote, the midrib raised; seeds 1.8-2.4 cm long and 2.8-3.8 cm wide, rela- tively thick and corky, without wings.