Calyx tube 0.8–1 mm. long, campanulate; lobes 1.5–2 x 0.7–1.2 mm., elliptic or oblong-lanceolate, scarcely winged on the keel at the apex, obtuse or subapiculate, 1-nerved.
Flowers mauve, purplish to blue, in axillary clusters, which are continuous and form a dense oblong terminal inflorescence; pedicels 2.5–4 mm. long; filiform.
Leaves subsessile, sometimes scarcely exceeding the subtended flower fascicle, 10–35 x 3–10 mm., spathulate-ovate or oblanceolate, cuneate at the base.
Corolla tube 1.5–2 mm. long, cylindric, smooth; lobes 0.9–1.2 x 0.5–0.6 mm., oblong-ovate, acute.
Ovary 1.8–2 x 0.8–1 mm., obovoid-cylindric; style 0.8–1.5 mm. long; stigma sub-bilobed.
Filaments 0.25 mm. long; anthers 0.25–0.3 mm. long, ovoid-ellipsoid.
Stem up to 6–7(12) cm. long, branched, 4-ridged, almost winged.
Seeds c. 0.25 mm. in diam., globose, minutely scrobiculate.
Capsule 2–2.2 x 0.9–1.2 mm., obovoid.
Caespitose annual herb.