Liana; trunk to 10 cm diam, often 4-sulcate; bark smooth, gray; stems with 4 phloem arms in cross section; twigs subterete, glabrous to slightly lepidote, usually drying black with whitish lenticels, the nodes lacking glandular fields; tendrils simple; pseudostipules small, pointed, ovate. Leaves 2- or 3-foliolate; petioles 3.2-6.5 cm long; petiolules 0.9-4 cm long; leaflets ovate to elliptic-ovate, acuminate, rounded to subcordate at base, 4.5-17 cm long, 2.5-8 cm wide, weakly lepidote on both surfaces, drying dark gray or olive, the margins wavy, with a narrow, conspicuous, cartilaginous border. Racemes axillary or terminal; flowers each subtended by a deciduous bract ca 1 cm long; rachises, pedicels, and calyces puberulent; calyx cupular, 5-8 mm long, bilabiately split for 1-2 mm, usually with plate-shaped glands; corolla bright yellow, tubular-funnelform, 3-7 cm long, puberulent outside, glandular-lepidote inside on lobes; stamens included, the longest pair ca 1.8 cm long; anthers slightly divaricate, 2-3 mm long; staminodium 4-5 mm long; pistil 2.4-2.5 cm long; ovary cylindrical, 3-3.5 cm long, lepidote. Capsules oblong, 10-27 cm long, 2.5-3 cm wide, 1.4-2.2 cm thick, rounded at both ends, not compressed; valves woody and somewhat thickened, gray, with numerous, raised, tannish lenticels, the midrib obscure; seeds 1.7-2.1 cm long, 5.1-7.6 cm wide, the body thick, the wings thin, brown. Foster 1116 (DUKE).