Liana; stems with a prominent interpetiolar ridge, at first coarsely pubescent, minutely lenticellate; sap milky. Leaves opposite, glabrous; petioles ca 1 cm long, glandular in axils; blades elliptic to oblong-elliptic or obovate, very abruptly acuminate and falcate at apex, obtuse to rounded at base, 9-20 (30) cm long, 2.5-10 (15) cm wide. Corymbs axillary, pedunculate; peduncles mostly 1-6 cm long; pedicels 1-2.5 cm long, usually puberulent; flowers 5-parted; calyx lobes 10-15 mm long, ovate to narrowly triangular, each bearing a deltoid squamella inside at base; corolla salverform, constricted just below lobes, the tube greenish, to 18 mm long, pubescent inside at level of stamen attachment, bearing 5 slender appendages above stamens, the tube with a raised yellow rim, the lobes obliquely obovate, white with orchid lines near margin, to 14 mm long, spreading at anthesis; stamens half-exserted; anthers 4-5 mm long, connate and glued to stigma; nectaries thick at base, growing together, the margins thin, toothed, higher than ovary. Follicles paired, often united at apex, 20-40 cm long and 6 mm wide, glabrous; seeds to 14 mm long, +/- fusiform, flattened, glabrous but bearing an apical tuft of trichomes 2-3 cm long. Croat 13497. Southern Mexico to Panama. In Panama, ecologically variable; known from tropical moist forest in the Canal Zone, Bocas del Toro, San Blas, Los Santos, Herrera, Panama, and Darien, from tropical dry forest in Panama (Taboga Island), from premontane moist forest in Panama, from premontane wet forest in Colón Chiriqui, Coclé and Panama, and from tropical wet forest in Colón, Coclé and Panama.