Climbing perennial suffrutescent to 1 m tall. Stem erect, subhexagonal, angles rounded, glabrous. Lower leaves soon deciduous; petiole slender, 5 mm long, hirtellous; blade thin, lanceolate, 3-4 x 1.1.5 cm, margins ciliolate, acuminate, often apiculate upwards, narrowed and rounded at base and then shortly cuneate onto petiole, drying dark olive green, glabrous, cystoliths numerous; primary vein and secondary veins (4-6 pairs) more or less hirtellous. Flowers borne in shortly pedunculate cymes, these in axils of leaf-like bracts, becoming crowded and confluent upwards to form a dense terminal inflorescence to 6 cm long; primary bracts similar to leaves but commonly reduced and apiculate; peduncle 2-5 mm long, glandular puberulous; cyme branches short, 0.5-2 mm long, glandular puberulous, bracts subtending cymes linear, about 4 mm long, chartaceous, pilose, trichomes 1.5-2 mm long; cymule bracts similar in size or anterior one slightly smaller than other, both elliptic to ovate, 12-14 x 4-6.5 mm, acuminate and mucronate at tip, cuneate at base, firm, 5-veined from base, green with whitish base, minutely dotted with yellowish glands, margin ciliate with straight trichomes of 1.5-2 mm long; bracteoles whitish-green, linear-lanceolate, about 5 mm long, hirsute. Calyx whitish-green, about 4 mm long, minutely puberulous, lobes narrowly subulate-triangular, 1.5-2 x 0.5 mm wide at base; corolla purple, 17-20 mm long, glabrous except hirtellous medial portion and outer surface of lips, tube cylindrical, about 9 mm long, 1 mm wide basally, 2 mm wide apically, upper lip obovate, 8-11 x 4 mm, rounded or obtuse, lower lip narrowly ovate, 8-11 x 2.5 mm, 3-lobed at apex, lobes about 0.5 mm long, rounded, pilose, middle one 0.5 mm wide, lateral ones slightly narrower; stamens exserted about 7 mm beyond mouth of corolla tube, filaments flattened, glabrous, anther thecae superposed, 1 x 0.5 mm; disk low and cupuliform; ovary glabrous. Capsule 5 x 1 mm, pubescent, retinacula 1 mm long, obliquely cucullate and acute; seeds not seen.
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