Australian Tropical Rainforest Plants - Online edition

Dichapetalum papuanum (Becc.) Boerl.


Shrub (woody or herbaceous, 1-6 m tall)
Vine
Click/tap on images to enlarge
Flowers. © Barry Jago
Leaves and Flowers. © CSIRO
Leaves and fruit. © CSIRO
Fruit, three views, dehiscing, cross section and seed. © W. T. Cooper
Scale bar 10mm. © CSIRO
Cotyledon stage, hypogeal germination. © CSIRO
10th leaf stage. © CSIRO
Vine stem bark and vine stem transverse section. © CSIRO
Family

Boerlage, J.G. (1890) Handleiding tot de Kennis der Flora van Nederlandsch Indie 1: 199.

Stem

Can grow into a tree-top vine but often flowers and fruits when still at the shrub stage. Vine stem diameters to 3 cm recorded. Stem wood very tough, hard to cut, lacking vessels or vessels not obvious. Vascular rays obvious when viewed with a lens.

Leaves

Leaf blades about 7.5-15 x 2.5-5.5 cm, petioles about 0.3-0.6 cm long. Stipules +/- almost linear, hairy, about 1-1.5 mm long, inconspicuous and caducous. Lateral veins about 5-7 on each side of the midrib forming indistinct loops inside the blade margin. Many of the tertiary veins form an angle of about 90 with the midrib. Leaf blades much paler on the underside where the venation is more obvious. The younger leafy twigs usually reddish-brown and marked by pale-coloured lenticels.

Flowers

Flowers small, about 2 mm diam. Petals truncate to emarginate at the apex. Staminodes closely resemble functional stamens. Base of the ovary surrounded by 2-lobed yellow glands. Style quite short. Stigma 3-lobed. Two ovules per locule.

Fruit

Fruit about 10-15 mm diam. Calyx lobes persistent at the base of the fruit. Cotyledons large and fleshy.

Seedlings

First pair of leaves with pale hairs on both the upper and lower surfaces but mainly on the midrib and on the margin. At the tenth leaf stage: stipules small, up to 1 mm long, clothed in pale, prostrate hairs, leaf blade with pale hairs but mainly on the midrib and on the margin. Lateral veins forming loops inside the blade margin. Seed germination time 91 to 202 days.

Distribution and Ecology

Occurs in CYP and NEQ. Altitudinal range from near sea level to 1150 m. Grows in well developed rain forest on a variety of sites. Also occurs in Malesia.

Natural History & Notes

When this species assumes the stature of a vine the stem wood produced is exceedingly hard with a very high specific gravity. This species should be treated with caution as some species of Dichapetalum produce fluoroacteate which is very poisonous.

Synonyms
Dichapetalum papuanum (Becc.) Boerl. subsp. papuanum, Flora Malesiana Series I 5: 309(1958). Chailletia papuana Becc., Malesia 1: 176(1877), Type: West New Guinea, Ramoi, Beccari PP. 307; lecto: FI. Dichapetalum australianum C.T.White, Proceedings of the Royal Society of Queensland 53: 211(1942), Type: Queensland, Slopes of Mt. Fraser, 16 Apr. 1932, L.J. Brass 2510; holo: BRI.
RFK Code
3054
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