Weak prostrate herb, forming mats to c. 15 cm diam., or stems ascending to 40 cm or more when submerged. Leaves ovate, elliptic or oblong, mostly c. 2–5 mm long, 1–3 mm wide (but submerged forms to c. 15 mm long, 6 mm wide); stipules c. 1 mm long, soon disintegrating. Flowers subsessile in axil of only 1 leaf of any pair; sepals and petals usually 3; sepals narrow-elliptic, c. 0.5 mm long, green; petals orbicular, c. twice as long as sepals, green or pink. Capsule 1.5–2.5 mm diam. Seeds numerous, c. 0.5 mm long. Flowers mainly Sep.–Jan.
LoM, MuM, Wim, GleP, VVP, VRiv, MSB, RobP, MuF, GipP, OtP, WaP, Gold, CVU, GGr, DunT, NIS, EGL, EGU, WPro, HSF, HNF, Strz, MonT, VAlp. All States. New Zealand. Widespread and rather common, usually on wet mud beside lakes, dams, watercourses, etc., occasionally occurring in still or slow-moving water to 1 m deep.
