Erect, decumbent or ascending annual, 5–15(–25) cm tall; stems usually diffusely branched, glabrous to rarely slightly pubescent. Leaves sessile or shortly petiolate, ovate, ovate-lanceolate or elliptic, 2–5(–16) mm long, 1–5(–8) mm wide, apex acute or obtuse, margins entire, or larger leaves occasionally minutely, shallowly dentate, 1–3(–5)-veined; petiole 0­–2 mm long. Flowers axillary or in terminal racemes, slender; pedicels (5–)7–12 mm long in flower, extending in fruit to 9–17(–25) mm long. Calyx (1–)2–4 mm long, glabrous or with few glandular hairs (e.g. Kibuwa 2450 from Kenya), divided almost to base; lobes lanceolate to linear-lanceolate, up to 0.5 mm wide, acute. Corolla white or pale blue, with darker blue or purple markings especially towards base, 4–7(–12) mm long, upper lip emarginate to shallowly bifid. Fertile stamens 2; filaments 0.4–1 mm long; staminodes two, 0.2–0.5 mm long, slender, clavate at apex occasionally with short spur ± 0.7 mm long just below. Capsule obovoid or broadly cylindric-ellipsoid to subglobose, 1.5–4.5(–6) mm long, 1–2 mm broad, usually slightly longer than calyx. Fig. 25, p. 84.