Australian Tropical Rainforest Plants - Online edition

Polyosma rigidiuscula F.Muell. & F.M.Bailey ex F.M.Bailey

Herb (herbaceous or woody, under 1 m tall)
Shrub (woody or herbaceous, 1-6 m tall)
Click/tap on images to enlarge
Flowers. © T. Hawkes
Leaf and flowers. © CSIRO
Leaves and Flowers. © A. Ford & F. Goulter
Fruit. © T. Hawkes
Scale bar 10mm. © CSIRO
10th leaf stage. © CSIRO
1st leaf stage, cotyledons absent. © CSIRO

Bailey, F.M. (1890) Queensland Department of Agriculture and Stock. Botany Bulletin 1: 4. Type: Summit of Mt. Bartle Frere, Bellenden-Ker Expedition, August 1889.


White granular stripes in the outer blaze. Fine oak grain in the inner blaze.


Lateral veins forming loops inside the blade margin. Midrib depressed on the upper surface. Leaf blades about 6-10.5 x 1.5-4.5 cm, broadest towards the apex, margin very sparsely toothed, with about 1-3 teeth on each side. Terminal buds clothed in pale brown prostrate hairs.


Calyx sericeous on the outer surface, lobes about 0.5 mm long. Corolla sericeous on the outer surface, about 7-12 mm long, lobes about 1 mm long. Staminal filaments about 4.5-7 mm long. Style about 6-10 mm long, stigma terminal, +/- 2-lobed.


Fruits glabrous or sparsely puberulous, +/- globular, about 12 x 12 mm. Seeds about 11 x 6 mm, rostrate at the apex.


Cotyledons (when present) linear, about 8-11 mm long. First pair of leaves with deeply serrate margins, often three-pronged. At the tenth leaf stage: leaf blade oblanceolate to obovate, apex acuminate, base attenuate. Margin with 1-3 peg-like teeth on each side towards the apex. Midrib hairy, +/- flush with the upper surface of the leaf blade. Lowe surface of the leaf blade sparsely clothed in short, translucent, prostrate hairs. Petiole and stem clothed in prostrate hairs. Seed germination time 145 to 260 days.

Distribution and Ecology

Endemic to NEQ. Altitudinal range from 950-1600 m. Grows as an understory tree or shrub in mountain rain forest.

RFK Code
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