Acacia stenoptera Benth., London J. Bot . 1: 325 (1842)
Subshrub to 0.5 m high, occasionally taller, often straggly. Branchlets angled, usually glabrous. Phyllodes continuous with branchlets, usually forming narrow stem wings 0.5–3 mm wide; free portion of phyllodes flat to compressed, straight or recurved, usually 1–3 cm long, 1–4 mm wide, pungent, green, usually glabrous; midrib prominent; upper margin flat, 2-nerved; gland not prominent, near base. Inflorescences simple, 1 or 2 per axil; peduncles 3–10 (- 20) mm long, glabrous or appressed-puberulous; heads globular, large, rather loosely 7–12-flowered, cream to golden; buds large, acute or apiculate. Flowers 4-merous; sepals united; petals flabellate-striate. Pods long-stipitate, to 10 cm long, 5–10 mm wide, thinly coriaceous-crustaceous, reddish, glabrous; margins winged. Seeds oblique, oblong, 5 mm long; aril terminal, conical.
Occurs from near Mingenew S to Mount Barker, south-western W.A. Grows in sand and laterite, in heath, scrub, woodland and open forest.
A very variable species. Branchlet and phyllode nerves are sometimes appressed-puberulous or muricate. These variants may resemble A. ataxiphylla subsp. magna which is distinguished by its 5-merous flowers and acuminate bracteoles and calyx lobes. Petal striations are strongest on specimens from between Perth and Mount Barker. A variant with linear, uncinate, often muricate phyllodes 3–9 cm long and non-winged stems is scattered at a few locations from between Bindoon and New Norcia, near York and S to Mt Dale (e.g. 30 km S of York on Yarra Rd, R.J.Cumming 2771A & B , PERTH). Elsewhere the phyllodes are rarely muricate or uncinate and not reaching 9 cm in length, also except for some specimens from Mingenew-Three Springs and Pingelly-Kojonup areas stem wings are present.
Type of accepted name
Swan R., J.Drummond s.n. ; syn: K; Swan R., W.A., C.Fraser ; syn: BM, K, NSW, NY; Vasse R., W.A., Mrs Molloy ; syn: CGE, K.
Illustrations
F. von Mueller, Iconogr. Austral. Acacia dec. 1 [pl. 1] (1887); M.Simmons, Acacias Australia 2: 13 (1988).
Representative specimens
W.A.: c. 14.5 km from Three Springs towards Eneabba, E.M.Canning WA/68 3343 (PERTH); Swan R., J.Drummond 2: 145 (BM, CGE, E, G, K, LUND, NSW, OXF, P, W); c. 14.5 km N of Mount Barker on Albany Hwy, S.Paust 12 (PERTH); Sussex district [between Capel and Toby Inlet], L.Preiss 992 (C, G, GOET, HBG, K, L, LUND, MO, NAP, P, RO, STR, W); 44.9 km N of Bindoon on Great Northern Hwy, M.D.Tindale 1268 (K n.v. , MEL n.v. , NSW, PERTH: variant).
(BRM)