Australian Tropical Rainforest Plants - Online edition

Brillantaisia lamium (Nees) Benth.


Weed
Herb (herbaceous or woody, under 1 m tall)
Shrub (woody or herbaceous, 1-6 m tall)
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Flower and fruit. © CSIRO
Scale bar 10mm. © CSIRO
Family

Bentham, G. (1849) Niger Flora : 477. Type: Tropical Africa.

Common name

Brillantaisia

Stem

Flowers and fruits as a shrub about 1-2 m tall.

Leaves

Leaf blades about 5-14 x 3.5-8 cm, upper and lower surfaces clothed in hairs. Small pale glands usually visible on the underside close to the margin. Lateral veins about 10-12 on each side of the midrib. Petioles about 2-6 cm long, often narrowly winged towards the point of attachment with the leaf blade. Stems or twigs decidedly 4-angled usually with a line of hairs between the points of attachment of the petioles.

Flowers

Inflorescence a large terminal cymose panicle clothed in erect glandular hairs. Flowers about 30 mm long. Calyx lobes about 8-10 x 1 mm. Corolla about 25 mm long. Corolla 2-lipped, the upper lip 2-lobed, the lower lip 3-lobed. Stamens about 20 mm long, anthers about 6 mm long, deeply divided at the base. Ovary about 6 mm long, the base surrounded by a cup-like disk about 1-1.5 mm high. Style hairy, about 20-25 mm long. Stigma narrow, spoon-shaped, about 3 mm long.

Fruit

Fruits about 25-40 x 2-3 mm. Seeds flattened about 1.5-2 x 1.5 mm. Testa densely clothed in fleshy prostrate hairs arranged in groups.

Seedlings

Cotyledons +/- semiorbicular, about 8-10 x 13-16 mm, apex obtuse to emarginate, base truncate. Cotyledons +/- 3-veined but venation difficult to see. First pair of true leaves opposite, ovate, upper and lower surfaces clothed in hairs. midrib raised on the upper surface. Stem 4-angled. At the tenth leaf stage: leaf blade ovate to lanceolate, base attenuate, both the upper and lower surfaces clothed in hairs. Petioles about 30-40 mm long, upper half +/- winged. Stem distinctly 4-angled and glabrous except near the base of the petioles. Seed germination time 4 days.

Distribution and Ecology

Originally from tropical Africa but now naturalised in NEQ. Altitudinal range no great, from near sea level to about 100 m. Grows in disturbed areas in rain forest and in agricultural waste areas. Also naturalised on some Pacific islands.

Natural History & Notes

This species is a prohibited import into Western Australia. The fruits produce an essential oil. Ayedoun, M.A., et al. (1997) Journal of Essential Oil Research 9:605-607.

RFK Code
3556
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