Naturalised populations are distributed mainly in the coastal areas of eastern Australia. It is most common in coastal southern and central Queensland. Scattered populations are also present in the coastal parts of northern Queensland, the Northern Territory and northern Western Australia (e.g. at Koolan Island). Also recorded in New South Wales (particularly near Grafton) and in non-coastal parts of Queensland and Western Australia.
Naturalised overseas in south-eastern USA (i.e. Florida), on Timor and on several Pacific Islands (i.e. Cook Islands, Fiji, French Polynesia, Niue, Midway Atoll and Hawaii).
Stems and Leaves
The stems and leaves contain a poisonous milky sap (i.e. latex). Older stems are pale brown or greyish in colour and relatively smooth, while younger stems are glossy green in colour and hairless (i.e. glabrous).
The leaves (5.5-15 cm long and 4-15 mm wide) are spirally arranged along the stems and often they are rather densely clustered near the tips of the stems. They are long and narrow (i.e. linear or lanceolate) in shape, with obscure leaf stalks (i.e. petioles) 1-4 mm long, and prominent central veins (i.e. midribs). These leaves are hairless (i.e. glabrous) with glossy green upper surfaces and paler, duller, undersides. The leaf tips are pointed or somewhat rounded (i.e. acute or sub-obtuse apices) and the leaf margins are curved downwards (i.e. recurved).
Flowers and Fruit
The bright yellow, or occasionally pale orange, flowers are arranged in several-flowered clusters near the tips of the branches. These flowers are tubular in shape (5-7 cm long) with five petal lobes (35-40 mm long) that are twisted and overlapping when in bud. The flowers also have five narrow green sepals (5-13 mm long) that are fused near the base (i.e. the calyx is deeply five-lobed) and are borne on stalks (i.e. pedicels) 15-37 mm long. Flowering occurs throughout the year, but mostly during summer and autumn.
The relatively large fruit is slightly fleshy with a hard centre (i.e. it is a drupe). It is somewhat broader than it is long (25-55 mm across) and is often somewhat triangular in outline (i.e. obtriangular) when mature. These fruit are green and glossy when young, but turn black and become slightly shrivelled as they ripen. Each fruit contains 2-4 large, flattened, seeds (about 35 mm long and 15 mm wide) in its woody centre.
