Herb or shrubby herb (30-)75-100 cm tall, branched from a subligneous base. Stem erect, quadrangular, branching, glabrate to pilosulous, lenticullate. Petiole 20-40 mm long, pilosulous; blade elliptic to narrowly obovate, 10-20 x 4-6 cm, firm, long-acuminate at apex, attenuate at base, partially decurrent on petiole, margin crenulate to crenate, glabrous or nearly so on both upper and lower surface; primary vein sulcate above, convex on lower surface, secondary veins (ca. 6 pairs), convex on both surfaces; leaves subtending inflorescence reduced, narrower than cauline leaves. Inflorescence a terminal spike or thyme, sessile to short-pedunculate; peduncle to 1.5 mm long; flowers opposite, 1-3 in axils of distal, foliose bracts; foliose bracts subulate to narrowly oblong, 10-20 x 1-2 mm; bracteoles narrowly triangular2-3 x 1 mm, suerulous and gland-dotted. Calyx 5-7 mm long, lobes subulate, 5-6 mm long, 0.75-1 mm wide at base, puberulent and minutely and densely gland-dotted; corolla pale yellow, sulphur-yellow or white with copper red apex, infundibular, 25-32(-38) mm long, glabrous except puberulous tube, tube cylindric, slightly bent near base, 12-15 mm long, limb suberect, lobes obovate, 8-9 x 6-8 mm, apically retuse; stamens slightly exserted from mouth of corolla, anthers 3 mm long; ovary and style puberulent. Capsule clavate15 x 4 x 3 mm, puberulent, green at base, apiculate and tinged purplish-brown apically, stipe 7 mm long; seeds dark brown, 2.75 mm in diam., glabrous, margin fringed by hygroscopic trichomes.
French Guiana present, Southern America: Brazil North (Amapá present)
French Guiana and Brazil (Amapá); 5 collections studied of which 2 from French Guiana (FG: 2).