Flowers yellow or pale yellow, in terminal few to many flowered dichotomous cymes, very rarely solitary; pedicels 0.3 mm. long; bracts 2–3 mm. long, elliptic-lanceolate.
Stamens inserted in the throat of the corolla; filaments 0.2–0.7 mm. long; anthers 0.5–0.7 mm. long with a minute ovoid-ellipsoid apical gland, without basal glands.
Leaves, sessile, 5-nerved; lamina 5–12 x 5–14 mm., ovate-circular to subreniform, cordate at the base, obtuse of shortly apiculate at the apex.
Calyx segments 5, 2.5–5 x 1.5–3 mm. long, ovate-lanceolate, acute at the apex, with a short wing on the keel, broader at or above the middle.
Ovary ellipsoid; style 3–5 mm. long, with or without a swelling above the middle; stigma subglobose more or less bilobed.
Stem slender, unbranched or branched (sometimes almost from the base), 4-ridged.
Corolla tube, 3–4 mm. long; lobes 1.5–3.5 x 0.8–1.2 mm. obovate-oblong.
Seeds 0.25–0.3 mm. in diam., cubical; testa frilled.
Erect herb of wet places up to 60 cm. high
Erect annual herb up to 40 cm. tall.
Capsule 2–4 mm. long, ellipsoid.
Flowers bright yellow.