Aquatic or mud-terrestrial, spreading or mat-forming, relatively robust with stems to c. 90 cm long, glabrous. Leaves variable, linear-spathulate to suborbicular, 2–25 mm long, 1–6 mm wide, 3–7-veined, petiolate; upper leaves rosetted. Flowers usually paired, a male and female together in 1 or both axils; bracteoles falcate, c. 1.5 mm long, membranous, persistent; stamen 1.4–4(–7) mm long, c. twice as long as fruit; styles erect, 2.5–4 mm long, becoming recurved in fruit, persistent. Fruit more or less circular, 1.2–1.7 mm long and wide, usually slightly longer than wide, subsessile, pale buff; wing prominent. Flowers and fruits mainly Sep.–Apr.
Wim, GleP, VVP, VRiv, MuF, GipP, OtP, WaP, Gold, CVU, GGr, DunT, NIS, EGL, EGU, WPro, HSF, HNF, OtR, Strz, MonT, HFE, VAlp. Also naturalised in WA, SA, Qld, NSW, Tas. Native to Europe, north Africa and Asia, widely naturalized. Widespread over all but north-western Victoria, growing in water or creeping on mud. .
