Suffruticose to 1.7 m tall. Stem leafless below, subtetragonal above, mostly glabrous except for a few trichomes near apex, bark red, exfoliating. Petiole 1-3(-4) cm long, sparsely pilose; blade elliptic to ovate or obovate, 3-25 x 2-15 cm, firm, margin entire, undulate, acuminate to cuspidate at apex, cuneate at base, dark green on upper surface, gray green on lower surface, glabrous on both surfaces; primary vein and secondary veins as well as margins of lower surface with a few trichomes. Inflorescence pendent, an elongated, terminal raceme or rarely a panicle, 23-58 cm long; flowers 2-4 (rarely more) per node on conspicuously glandular-puberulent rachis; lowermost bracts lanceolate and sterile, 5-9 mm long, upper bracts reduced, 4 x 0.5 mm; bracteoles immediately inside each bract and similar, somewhat smaller. Calyx lobes narrowly triangular or subulate, 5-8 x 1 mm, pubescent with spreading, purplish, conspicuously glandular trichomes; corolla red, distinctly curved, bottle-shaped, 40-50 mm long, tube 2 mm wide at base, 5-7 mm wide at middle, puberulous throughout with some glandular trichomes, upper lip with shallow ovate lobes of 3-4 x 3-4 mm, lower lip similar; stamens exserted beyond corolla lips, filaments 35-38 mm long, glabrous, anthers 3-4 mm long, staminodes 1.5-2 mm long, apically capitate, glabrous; ovary glabrous, style 15 mm long, glabrous. Capsule clavate, 20 x 5 x 5 mm, ciliolate; seeds 4, oval.