Robust, erect, clumped perennial herb, 15-100 cm, the underground parts not scaly; Inflorescence erect. Flowers erect, borne in the axils of upper leaves. Sepals 3-5.5 by 0.8-1.6 mm. Petals obovate, 3-5 by 2-3.2 mm, white or very pale pink, the notch c. 1 mm deep. Capsule 3-5(-6) cm long, on a pedicel 0-2 cm. Seeds 0.9-1.2 mm long, 0.35-0.45 mm thick, finely papillose, brown, not beaked, obovoid, blunt at both ends, the coma 5-8 mm long, white.
Argentina present, Asia-Tropical, Australasia, East Java present, Lesser Sunda Is present, Lombok present, Mt Tengger present, New Zealand present, South America present, Southern America: Brazil South (Santa Catarina present); Uruguay (Uruguay present), Sumbawa present, Timor present
Very widely distributed, South America (Argentina, Uruguay, Brazil: Santa Catarina), New Zealand, Australia, and Malesia: Lesser Sunda Is. (Timor, Sumbawa, Lombok) and East Java (Mt Tengger).
Variable species. The Malesian specimens belong to a highly autogamous Australian form with small white flowers which occurs in swampy places throughout the lowlands of Australia (from Queensland to temperate W. Australia and Tasmania) and is predominant in New Zealand. I have assumed that it came there from Australia and has spread again from New Zealand to South America, either by natural dispersal or by man.
ALLAN - in Fl. New Zeal. 1961: 279
BURBIDGE & GRAY, Fl. A.C.T. 1970: 276
BACK. & BAKH. f. - in Fl. Java. 1963: 262
RAVEN - in D.S.I.R. New Zeal. Bull. 1976: f. 63-64, 65-66 (maps).
HAUSSKNECHT, Monogr. Epilob. 1884: 291
H. LEVEILLE, Ic. Gen. Epilob. 1910: t. 18
WILLIS - in Handb. Pl. Vict. 1972: 464