Ammannia prieuriana Guill. & Perr.

Annual erect or straggling mostly much-branched herb, 0.1–1.2 m. tall, but can be an unbranched ± ephemeral, 10–18(–25) cm. tall (see note); submerged stems sometimes inflated and occasionally with purplish green spongy growth; young stems 4-angled, ± winged above.. Leaves linear, oblong or narrowly lanceolate, 1–8.5 cm. long, 0.15–1.1 (– 1.5) cm. wide, narrowed to the apex, cordate to ± hastate and auriculate at the base.. Flowers in dense 3–20-flowered cymes 4–6(–9) mm. long; peduncle 1.5–3 mm. long; pedicels 1–4 mm. long, the median one longest, the others mostly short.. Calyx green striped pink, or red; tube campanulate, (0.6–)1–1.5 mm. long; lobes 4, triangular, 0.3–0.7 mm. long; appendages horn-shaped, short, ± 0.3 mm. long.. Petals pink, mauve or white, 4, obovate, 0.5–1.3 mm. long, soon falling.. Stamens 4, inserted near middle of tube, 1.2–1.5 mm. long.. Ovary globose, 0.7–1 mm. in diameter; style (0.3–)0.5–1 mm. long.. Capsule red, globose, 1.5–1.8 mm. in diameter, exserted.. Seeds dark brown, concave-convex, 0.2–0.4 mm. long.. Fig. 13.

In marshy places.