Australian Tropical Rainforest Plants - Online edition

Polyalthia submontana subsp. sessiliflora (Jessup) Jessup

Shrub (woody or herbaceous, 1-6 m tall)
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Flower [not vouchered]. © R. Jensen
Flower [not vouchered]. © R. Jensen
Leaves and Flowers. © CSIRO
Scale bar 10mm. © CSIRO
10th leaf stage. © CSIRO
Cotyledon stage, semi-durian germination. © CSIRO

Jessup, L.W. (2017) Austrobaileya 10(1): 64.


Usually flowers and fruits as a shrub about 1-4 m tall.


Twig bark strong and fibrous when stripped. Young shoots clothed in brown or golden appressed hairs. Leaf blades about 6-13 x 1.5-4.5 cm. Upper surface of the leaf blade arched between the lateral veins. Lateral veins form loops well inside the blade margin. Oil dots visible with a lens.


Flowers about 8-11 mm diam. Ovaries hairy, clothed in downy copper-coloured appressed hairs.


Fruit about 19 x 13 mm. Seeds about 9 x 8 mm. Embryo about 1 mm long. Cotyledons about as wide as the radicle.


First pair of leaves ovate, alternate, margins smooth. At the tenth leaf stage: leaf aromatic when crushed; leaf blade ovate to elliptic, apex acuminate to acute, base cordate to obtuse. Stems and terminal buds clothed in brown hairs. Lateral veins difficult to distinguish but forming loops inside the blade margin. Seed germination time 138 to 203 days.

Distribution and Ecology

Endemic to NEQ, known only from a few localities on the Atherton Tableland. Altitudinal range from 700-1300 m. Grows as an understory shrub in well developed upland rain forest, more common on soils derived from vesicular basalts.

Natural History & Notes

Food plant for the larval stages of the Green Spotted Triangle Butterfly. Sankowsky & Neilsen (2000).


Haplostichanthus submontanus subsp. sessiliflorus JessupFlora of Australia 2: 449 (2007). Type: Queensland, Curtain Fig near Yungaburra, 5 Dec. 1984, L.W. Jessup 695. Holo: BRI.  Haplostichanthus sp. (Topaz LWJ 520), Australian Tropical Rain Forest Plants, Trees , Shrubs & Vines : (2003).

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