Erect or rarely straggling herb 0.35–3 m. tall, with single unbranched or sparsely branched glabrescent pubescent or hairy stem. Leaf-blades ovate-elliptic or rarely linear, 1.5–9.5 cm. long, 0.7–3.2 cm. wide, ± acute at the apex, rounded or cuneate at the base, pubescent to densely hairy on both surfaces, or glabrous above and pubescent beneath on the nerves, or altogether glabrous save for a very minute pubescence near the edges above and on the venation beneath; petiole obsolete or 1–6 mm. long; stipules with 1–3 flat linear setae 1–5 mm. long, 0.2–1 mm. wide, and also 2–6 short setae or sessile colleters from a short base. Flowering inflorescence 1–6.5 cm. long, becoming 4–37 cm. long in fruit, with a peduncle 0–30 cm. long; solitary nodal flower with pedicel up to 2 cm. long. Calyx-tube ± 2 mm. long, glabrous to hirsute; lobes very unequal, 1–3 foliaceous, lanceolate, 0.5–2.4 cm. long, 1.2–4.8 mm. wide, the rest 1–4 mm. long, 0.5–1.5 mm. wide. Corolla-tube 1.7–2.7 cm. long, sparsely hairy or glabrous below, 0.25–2.3 mm. wide below, dilated above to 1.25–3 mm. wide for a distance of 3–5 mm., the dilation urceolate and usually rounded at the base, externally hairy with long multi-cellular crimson or purple hairs; lobes ovate, orbicular or elliptic-spathulate, 0.5–1.8 cm. long, 0.25–1 cm. wide, mucronate from the emarginate tip, connate at the base for 0.5–1.5 mm.; throat orifice 0.5–1.5 mm. in diameter; throat densely hairy, the apical hairs crimson and spreading over the orifice and connate parts of the corolla-lobes. Anthers completely included. Style exserted 0–5 mm.; stigmas elliptic, 0.5–1 mm. long. Fruit oblong, compressed, chestnut or purple-brown, 0.6–1.2 cm. long, 4–6 mm. wide, 2.5–5 mm. thick (rarely smaller, 5 × 3.5 mm.), strongly ribbed, pubescent or hairy; dehiscence apical and accompanied by some longitudinal splitting. Seeds angular, ± 0.7 mm. long.
