Leaves and Flowers. Copyright B. Gray
Scale bar 10mm. Copyright CSIRO
Cotyledon and 1st leaf stage, epigeal germination. Copyright CSIRO
Cotyledon stage, epigeal germination. Copyright CSIRO
10th leaf stage. Copyright CSIRO
Acacia hylonoma Pedley
Pedley, L. (1978) Austrobaileya 1: 214. Type: Qld, east of May Peak, Yarrabah Aboriginal Reserve, Dec. 1972, Webb & Tracey 10764; holo: BRI.
Racosperma hylonomum (Pedley) Pedley, Botanical Journal of the Linnean Society 92: 248(1986), Type: ?.
Yarrabah Wattle; Wattle
Bark usually somewhat yellowish-brown.
Leaves green, phyllodineous. Leaf blades about 8-13.5 x 0.7-1.6 cm. A gland usually present on the upper edge of the leaf blade, about 9-17 mm from the base. Veins longitudinal, anastomosing, about 4-10 veins more prominent than the rest. A small ridge normally apparent running down the leafy twigs from the base of each petiole.
Inflorescence usually consisting of two pairs of heads, peduncles about 5-8 mm long, glabrous, heads about 25-flowered. Calyx glabrous, about 1.1-1.2 mm long, eventually separating into distinct lobes. Corolla about 1.8-2 mm long, about 1.5 times as long as the calyx. Stamens about 2.5 mm long. Ovary glabrous.
Pods flat, about 9 x 1.2 cm, rather thin and papery. Seeds dull brown, longitudinally oriented in the pod, about 5 x 3.5-4 mm. Funicle brownish when dry, slightly thickened and folded but not expanded beneath the seed and not encircling the seed.
Cotyledons oblong or elliptic, about 4 mm long. First leaf pinnate, second leaf bipinnate. By the third or fourth leaf stage: leaves bipinnate, petiole often expanded. At the tenth leaf stage: leaves phyllodineous, linear, +/- falcate, glabrous, about 4-6 main parallel veins run from the base to the apex; a small gland usually present on the upper edge of the leaf blade near the junction of the leaf blade and the petiole; stipules very small, visible only with a lens; stellate hairs visible with a lens.
Distribution and Ecology
Endemic to NEQ, restricted to a few localities. Altitudinal range from near sea level to 400 m. Grows in well developed lowland and upland rain forest. This species is favoured by disturbance and is a component of rain forest regrowth.