Lysimachia japonica
Thunb.Prostrate perennial with stems to c. 30 cm long, rooting from lower nodes. Leaves petiolate, opposite, subopposite or alternate, lamina broadly-ovate, 6–14 mm long, 5–14 mm wide, both surfaces with scattered erect septate hairs and sparse sessile glands. Flowers solitary in axils; sepals 5–7 mm long, long-acute, virtually free, entirely green and membranous; petals ovate, bright yellow, not or barely exceeding the sepals. Capsule globose, slightly shorter than calyx; seeds elliptic, unequally trigonous, c. 1 mm long, dark brown, minutely tuberculate. Flowers ?Jan.–Feb. (specimen in mature fruit Apr.).
EGL, EGU. Also Qld NSW. India, China, Japan, Indonesia, Papua New Guinea. In Victoria known from two collections (1971, 1997) from shaded gully vegetation near Toorloo Arm, north of Lake Tyers, where locally common.
Although sometimes treated as naturalised (e.g. Fensham 2019, Walsh 1996), the species is tentatively treated here as being indigenous to Victoria on the basis of its occurrence in intact native vegetation, and its occurrence in Queensland and New South Wales (where regarded as native), which although patchy, is more or less continuous with its distribution through south-east Asia. The relatively late date of the first Australian collection (1881) is puzzling however.
Walsh, N.G. (1996). Primulaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 3, Dicotyledons Winteraceae to Myrtaceae, pp. 517–522. Inkata Press, Melbourne.
SpinningFensham, R.J.; Laffineur, B. (2019). Defining the native and naturalised flora for the Australian continent. Austral. J. Botany.
Walsh, N.G. (1996). Lysimachia, in N.G.Walsh & T.J.Entwisle (eds). Flora of Victoria 3: 517–519.
