Acacia oldfieldii F.Muell., Fragm. 4: 7 (1863)
Openly branched shrub to straggly tree 1.5- 5 m high. New growth citron golden-sericeous. Branchlets glabrous. Phyllodes commonly patent to reflexed, linear-elliptic to linear-oblanceolate, straight to shallowly incurved, 7- 16.5 long, 3- 5 mm wide, the margins yellow, acute to caudate-acuminate with straight to recurved tip, thin-coriaceous, glabrous, with numerous closely parallel, occasionally anastomosing, scarcely evident nerves. Inflorescences simple, 2 per axil; peduncles 1.5- 4 mm long, appressed-puberulous or glabrous; receptacle glabrous or sparsely puberulous, the hairs commonly white and subappressed; spikes commonly 30- 45 mm long, 4- 5 mm diam., loosely flowered, bright golden. Flowers 4-merous; sepals partially united. Pods linear, raised over and constricted between seeds, to 10 cm long, 2- 4 mm wide, thin-crustaceous, glabrous. Seeds longitudinal, elliptic, 3.5- 4 mm long, glossy, black; aril terminal, subconical.
Localised but common in coastal area from near Eradu (E of Geraldton) N to Kalbarri Natl Park, W.A. Grows in sand, sandy loam, and clayey sand overlying sandstone, limestone, ironstone and gravel, in dense sandplain scrub or shrubland with species of Calothamnus and Melaleuca .
G.Bentham, Fl. Austral. 2: 404 (1864), treated A. oldfieldii as conspecific with A. acuminata . Macro-morphological characters suggest that these two species are closely related although recent (unpublished) genetical data suggest that they not especially close, see B.R.Maslin reference at end of A. acuminata treatment. In A. acuminata the mature phyllodes have ciliolate margins, at least in their apical half. The phyllodes of A. oldfieldii are similarly adorned at very early stages but almost immediately, certainly by maturity, are glabrous. Additionally, the more densely flowered spikes are subsessile in A. acuminata , the peduncles rarely reaching 2 mm in length, and the receptacle is commonly puberulous with golden hairs. Also related to A. drepanophylla .
Type of accepted name
Murchison R., W.A., A.Oldfield s.n. ; syn: MEL, K, PERTH; Murchison R., W.A., A.Oldfield 53 ; syn: MEL, PERTH.
W.A.: S of Eradu, A.M.Ashby 1896 (PERTH); 24.1 km from Kalbarri Coast road (Grey St) towards Ajana, Kalbarri Natl Park, R.S.& R.A.Cowan A815 (CANB, K, NY, PERTH, US); 0.5 km S of Yuna on Council reserve, E.N.S.Jackson 3172 (PERTH); 14.5 km N of Murchison R. on North West Coastal Hwy, B.R.Maslin 3649 (PERTH).
(BRM & RSC)