Rotala serpiculoides Welw. ex Hiern

Erect or decumbent simple or branched annual, 3–30 cm. tall; stem green or tinged with red.. Leaves narrowly elliptic-oblong to oblanceolate, decussate, 0.5–2.5 cm. long, 1–6 mm. wide, obtuse at the apex, narrowed at the base into a short petiole, spreading or suberect.. Flowers crimson or reddish purple, 3–4-merous, (1–)3–12 in axillary sessile racemose clusters; rarely with vegetative growth continued beyond the inflorescence rhachis; pedicels 0.4–0.5(–1.3; –2 fide Cook) mm. long; bracteoles linear-subulate ± 1 mm. long.. Calyx-tube usually campanulate, ± 0.6 mm. long; lobes 4(–5), triangular, 0.4–0.7 mm. long, acuminate; appendages absent.. Petals absent, (or 1, white, fide Milne-Redhead & Taylor 10873).. Stamens 1(–3), yellow, included.. Ovary reddish, ellipsoid, 0.5–1 mm. long; style very short; stigma cream, capitate.. Capsule ellipsoid or globose, 1–1.5 mm. long, 3(–4)-valved.. Seeds brownish, subglobose or compressed-ellipsoidal, concavo-convex, 0.25–0.5 mm. long.. Fig. 15/23–27, p. 53.