Vandellia cambodgiana

Small annual herbs, 5–30–(40) cm tall; stems erect, quardrangular, glabrous, except densely hispid hairs at nodes and young shoots, somewhat rooting at the nodes. Leaves pinnately nerved; sessile; lamina lanceolate, narrowly ovate or elliptic, 0.5–2.2 x 0.1–0.8 cm, apex acute or obtuse, base cuneate or attenuate, margins entire or crenate, sparsely hispid hairs. Inflorescences solitary and axillary umbellate or somewhat short raceme or umbel-like; pedicel 1–1.7 cm long, hirsute hairs; bracts lanceolate or leaf-like, 0.5–2 x 2–11 mm. Calyx 5–7 mm long, 5-lobed; lobes divided to the base, linear to lanceolate, apex acutminate, densely hispid hairs. Corolla purple, 5–8 mm long; upper lip emarginated, 3–3.5 mm wide; lower lip broadly 3-rounded lobes, often acute, 5–6 mm wide. Stamens 2 fertiles, 2 rudimentary or sterile anthers; posterior filaments straight, 1–1.2 mm long; anterior filaments (0.2–)1.2–1.6 mm long, obscurely knob or short linear spurs, 0.1–0.3 mm. Capsules ellipsoid, glabrous, 2.5–4 x 1–3 mm, shorter than calyx lobes. Seeds numerous, ovoid, narrowly ellipsoid, subglobose, 0.35‒0.54 x 0.29‒0.43 mm, scorbiculate-foveolate