Hydrocotyle bonariensis
Lam. Largeleaf PennywortPerennial glabrous herb with robust, creeping stems that root at nodes. Leaf-lamina rather fleshy, peltate, 3–6 cm across, shallowly lobed, margin crenate; petiole to 15 cm long; stipules scarious, 2–4 mm long. Umbels compound, 1–6 cm across, many-flowered; rays 5–12, spreading; flowers in whorls in interrupted or sometimes branched spike-like structures and at base of rays; peduncle to 11 cm long, usually exceeding leaves; pedicels 2–20 mm long; involucral bracts lanceolate, acute. Petals white to creamy yellow. Fruits transversely ellipsoid, 1.5–2 mm long, 2.5–3 mm wide, base and apex emarginate; dorsal and lateral ribs prominent. Flowers mainly spring and summer.
GipP, WaP, EGL, EGU, WPro. Also WA, SA, Qld, NSW. Native to South America. Usually naturalised in coastal or near-coastal areas where it colonises dunes, cliff-faces and swampy areas, but also naturalised in constructed wetlands at Cairnlea (a western suburb of Melbourne).
Duretto, M.F. (1999). Apiaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 4, Cornaceae to Asteraceae, pp. 256–258. Inkata Press, Melbourne.