Australian Tropical Rainforest Plants - Online edition

Abroma molle DC.


Shrub (woody or herbaceous, 1-6 m tall)
Click/tap on images to enlarge
Flowers [not vouchered]. © G. Sankowsky
Leaves, flower and fruit. © B. Gray
Scale bar 10mm. © CSIRO
Cotyledon stage, epigeal germination. © CSIRO
10th leaf stage. © CSIRO
Family

Candolle, A.P. de (1824) Prodr. 1: 485. Type: Moluccas, holo: P?.

Stem

Occasionally grows into a small tree but usually flowers and fruits as a shrub about 2-3 m tall.

Leaves

Twigs armed with very short, broad-based spines. Leaf blades about 6-23 x 5.5-20 cm. Underside of the leaf blade clothed in short simple hairs and much larger 3 or 4-armed irritant hairs. Stipules about 2-4 mm long. Twig bark strong and fibrous when stripped. Mucilage glands visible in the twig pith.

Flowers

Calyx lobes about 15-20 x 3-5 mm. Petals broad at the base, 5-ribbed and hairy, above that they narrow into a claw and then expand into a limb about 12-15 mm long. Staminal tube 5-lobed at the apex with anthers attached in groups of three on the outer surface at the junction of the tube and lobes.

Fruit

Fruit a large capsule, about 4-5 x 6-7 cm, 5-lobed, with branched hairs on the outer surface and with numerous long white hairs on the inner surface. Seeds about 3-4 x 2 mm. Testa thick and horny. Seeds almost completely hidden by hairs. Cotyledons much wider than the radicle. Funicle orange-brown, thick and fleshy, aril-like. Fruit hairs irritant.

Seedlings

Cotyledons orbicular, about 9-13 x 10-11 mm, petioles variable, up to 12-15 mm long. First pair of leaves +/- opposite, cordate, margins toothed, undersides clothed in pale erect and 3-armed hairs. At the tenth leaf stage: leaf blade +/- cordate, margin usually both toothed and lobed (usually 3-lobed) lower surface of the leaf blade clothed in pale simple hairs and much larger three or 4-armed irritant hairs. Upper leaf blade surface clothed mainly in pale simple hairs. Stipules linear, about 2-3 x 0.5 mm. Seed germination time 24 to 48 days.

Distribution and Ecology

Occurs in CYPNEQ and CEQ. Altitudinal range from near sea level to 200 m. Grows as an understory plant in disturbed gallery forest and lowland rain forest. Also occurs in Malesia.

Synonyms
Abroma mollis DC., Prod. 1: 485(1824), Type: Moluccas. Abroma augustum (L.) Murray, Systema Vegetabilium : 696(1784). Abroma fastuosa Vent., Hortus Botanicus Vindobonensis 3 : 3(1777), Type: (not cited). Abroma augusta (L.) L.f., Supplementum Plantarum : 341(1782).
RFK Code
3223
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