Acacias of Australia

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Acacia ampliata R.S.Cowan & Maslin




Restricted to near Mullewa with one collection from near Coolcalalaya (c. 100 km NNW of Mullewa), south-western W.A.


Shrub or small tree 2–5 m high. Branchlets slightly ribbed, silvery sericeous and with scattered patches of red-brown resin-hairs. Phyllodes ascending to erect, linear to linear-elliptic, straight to incurved, 8–19 cm long, 3–6 mm wide, acute, rigid, sparsely sericeous, striate by numerous closely parallel nerves; central nerve raised and conspicuous; marginal nerves broad. Inflorescences simple, 1 or 2 per axil; peduncles 3.5–9 mm long, with indumentum as on branchlets; heads obloid to short-cylindrical, 9–12 mm long, 7–8 mm diam., densely flowered, golden. Flowers 5-merous; sepals 1/2-united. Pods linear, slightly raised over and slightly constricted between seeds, to 11 cm long, 5–6 mm wide, coriaceous to crustaceous, invested with minute red-brown resin-hairs. Seeds longitudinal, broadly elliptic to elliptic-oblong, 4.5–6 mm long, shiny, dark brown-black; aril much-folded.


Grows in loam, sandy loam and sand in mallee scrub.


W.A.: c. 16 km E of Mullewa, A.M.Ashby 4509 (PERTH); S of Coolcalalaya, J.S.Beard 7149 (PERTH).


Most closely related to A. jamesiana which has normally tetragonous phyllodes 1–1.5 mm wide (rarely to 3 mm and flat) and pods 4 mm wide. Also related, but more distantly, to A. heteroneura subsp. heteroneura which has compressed-rhombic to flat phyllodes normally 5–7 cm long, 2–4 mm wide, globular heads with less densely arranged flowers, pods to 5.5 cm long and 2 mm wide, and mottled seeds.

FOA Reference

Data derived from Flora of Australia Volumes 11A (2001), 11B (2001) and 12 (1998), products of ABRS, ©Commonwealth of Australia


R.S.Cowan, B.R.Maslin