Perennial herb; Flowers 5-merous; Sepals glandular puberulous, elliptic, 3-4 by 2 mm, with obtuse apex, 3-nerved at the base. Petals white, oblong with rounded apex, slightly longer than sepals. Stamens 10, filaments 2-2.5 mm long. Ovary ovoid, c. 3 by 2 mm; Capsule c. 4 mm long. Seeds obliquely subrotundate, 0.6-0.8 mm, finely muricate.
Asia-Tropical: New Guinea endemic
In Malesia: endemic to New Guinea, only known from the type locality (Bele River, 18 km NE of Lake Habbema).
The species was identified by as S. echinisperma Hayata. Dr H. Hara, however, as mentioned by Merrill & Perry, l.c., has shown that the New Guinean plant is different from the Taiwanese species, that has proven to be S. japonica (Sw.) Ohwi, a species common in Japan. No material has been found in L.