Petalostigma banksii Britten & S.Moore

Moore, S. le M. (1903) The Journal of Botany 41 : 225. Type: Queensland, Endeavour River, 1770, Banks & Solander; holo: BM. Fide Airy Shaw (1980).

Quinine Bush

Can grow into a small tree but usually flowers and fruits as a shrub about 2-4 m tall.

Leaf blades about 2.5-3 x 1-1.2 cm, glabrous or sparsely pubescent on the underside. Twigs and terminal buds clothed in brown or cream-brown hairs. Stipules very small, about 1 mm long, or not visible.

Flowers about 3-4.5 mm diam. Tepals densely clothed in prostrate hairs on the outer surface but +/- glabrous on the inner surface. Stamens united in a central column with short free filaments. Anther connective and ovary pubescent. Ovules 2 per locule.

Fruit globular, about 10-12 mm diam. Seeds with a distinct caruncle at the base.

Cotyledons about 10-11 x 6-7 mm. First pair of true leaves hairy on both the upper and lower surfaces. At the tenth leaf stage: leaf blade elliptic, apex obtuse, upper and lower surfaces densely clothed in pale brown to off white hairs. Stem clothed in similar hairs. Stipules green, about 8 mm long, densely clothed in long white hairs. Seed germination time 651 days.

Endemic to Australia, occurs in NT, CYP, NEQ and CEQ. Altitudinal range from near sea level to about 900 m. Usually grows in open forest but also found in monsoon forest and vine thickets.