Procumbent or ascending glabrous perennial herb; stems branched, floating, to 50 cm long, rooting at nodes. Leaves opposite, broadly elliptic to more or less ovate, 0.5–2.5 cm long, 3–17 mm wide, entire; petiole 2–25 mm long. Flowers sessile, solitary or often paired in upper leaf axils; bracteoles minute, often caducous; sepals 4, green, c. 1 mm long, deltoid, acute; petals absent; stamens 4; ovary 4-celled. Fruit a 4-angled elongate-globose capsule, 2–5 mm long, readily and irregularly dehiscent; seeds free. Flowers mostly Dec.–May.
VRiv, MuF, GipP, CVU, NIS, EGL, EGU, HNF, VAlp. Also naturalised NSW, the Pacific region. Native through much of the Northern Hemisphere and Africa. In Victoria, confined to stream and lake margins mostly along the Murray River system upstream from about Barmah and also along the Mitchell River and its tributaries.
Source:
Jeanes, J.A. (1996). Onagraceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 3, Dicotyledons Winteraceae to Myrtaceae, pp. 930–942. Inkata Press, Melbourne.
