Australian Tropical Rainforest Plants - Online edition

Atalaya angustifolia S.T.Reynolds


Herb (herbaceous or woody, under 1 m tall)
Shrub (woody or herbaceous, 1-6 m tall)
Tree
Click/tap on images to enlarge
Leaves and Flowers. © CSIRO
Fruit. © CSIRO
Scale bar 10mm. © CSIRO
Cotyledon stage, epigeal germination. © CSIRO
10th leaf stage. © CSIRO
Family

Reynolds, S.T. (1981) Austrobaileya 1(3): 402. Type: Queensland, 107.2 km S of Laura (15 40 S, 144 30 E), 17 Sep 1971, A. Irvine 79; holo: BRI; iso: QRS.

Stem

May attain the dimensions of a small tree but usually flowers and fruits as a shrub.

Leaves

Leaflets sessile, blades about 3.5-9 x 0.3-0.7 cm. V-shaped in transverse section. Lateral veins not very obvious but forming loops inside the blade margin. Compound leaf petiole swollen at its junction with the twig. Compound leaf rhachis winged and ending in a terminal appendage.

Flowers

Inflorescence about 30 cm long. Sepals about 2.5-3.5 mm long. Petals about 5 mm long with hairy, bilobed scales attached to the inner surface near the base. Two yellow glands attached to the apex of each lobe on the scales. Stamens 8, anthers about 1.5 mm long, filaments about 4 mm long, clothed in hairs on the basal half. Pollen orange-yellow.

Fruit

Samaras (up to 3 per flower) about 27-36 mm long, wing 23-30 x 12-15 mm, clothed in short velvety hairs, and marked by numerous veins. Seeds about 6-8 mm long. Cotyledons fleshy, one enclosed by the other. Cotyledons much wider and longer than the straight or slightly curved radicle.

Seedlings

Cotyledons about 12-13 x 4-5 mm, unequal in size, rather thick and fleshy. Apex obtuse to truncate and oblique, base +/- auriculate. Venation not visible. Hypocotyl densely clothed in short white hairs. First leaves lanceolate to elliptic or oblong, glabrous, midrib slightly raised on the upper surface. At the tenth leaf stage: leaf long and strap-like +/- linear-oblong, about 6-10 x 0.6-0.8 cm, lateral veins numerous, more than 25 on each side of the midrib. Midrib raised on the upper surface. Irregular oil dots or glands visible with a lens only from the upper surface of the leaf blade.

Distribution and Ecology

Occurs in CYP and NEQ. Altitudinal range from 100-300 m. Often grows in open forest but also found monsoon forest and vine thicket. Seed germination time 12 days.

Natural History & Notes

An attractive shrub with horticulture potential in low rainfall areas. Narrow pendant foliage, showy flowers and long lasting winged fruits are its features.

RFK Code
3534
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