Acacia ataxiphylla Benth., Linnaea 26: 605 (1855)
Subshrub to c. 0.3 m high, prostrate or spreading-erect. Branchlets glabrous or hairy. Stipules linear triangular, 2–3 mm long, sometimes rigid but not spinose. Phyllodes continuous with branchlets but not forming cauline wings, narrowly linear, pentagonal when very narrow, straight to shallowly curved or shallowly sigmoid, 15–60 mm long, 1–2 mm wide, shallowly recurved to markedly uncinate at the sharply or coarsely pungent apex, with indumentum as on branchlets, 5-nerved, the 2-nerved adaxial margin 0.5–0.6 mm wide; midrib evident. Inflorescences simple, 1 per axil; peduncles 4–12 mm long, rarely 18 mm, hairy; heads globular to slightly obloid, 15–20-flowered; bracteoles and calyx lobes dark brown and long-acuminate. Flowers 5-merous; sepals 1/3–1/2 united; petals 2–3 mm long. Pods (immature, subsp. ataxiphylla only) narrowly oblong, curved, to 20 mm long and 4 mm wide, reddish brown, longitudinally striate, strigulose.
Scattered and infrequent in south-western W.A.
Two subspecies are recognised, but future studies may show that these are better treated as distinct species.
Heads c. 5 mm diam. (when dry) on slender peduncles usually 8–12 mm long; branchlets sparsely antrorsely puberulous or glabrous; summer flowering
Heads 7–9 mm diam. (when dry) on stout peduncles 4–7 mm long; branchlets moderately to densely tomentulose; winter flowering
Acacia ataxiphylla Benth. subsp. ataxiphylla
Prostrate, sprawling subshrub 0.2 m high and to 0.5 m across. Branchlets sparsely antrorsely puberulous or glabrous. Phyllodes rather slender, (15–) 20- 35 (- 50) mm long, 1–1.7 mm wide. Peduncles (6.5–) 8- 12 (- 18) mm long, slender, 0.4 mm diam. (when dry), antrorsely puberulous; heads c. 5 mm diam. (when dry), 15–20-flowered; bracteoles 1–1.5 mm long. Calyx 1/3–1/2 length of corolla; petals c. 2 mm long, with midrib normally thick and prominent at petal apices.
Occurs from Darkan S to Albany. Grows in clay loam or sand, with some gravel, in Eucalyptus woodland.
Sometimes resembling A. laricina var. laricina which is distinguished by its calyx lobes and bracteoles which are not long-acuminate and heads 20–30-flowered.
Type of accepted name
Swan R., W.A., J.Drummond 4: 6 ; lecto: K, fide B.R.Maslin, Nuytsia 12: 323 (1999); isolecto: BM, FI, G, K, MEL, NSW, OXF, P, PERTH, TCD.
W.A.: near Cranbrook, 86.5 km N of Albany, Dec. 1927, W.E.Blackall s.n . (PERTH); 150 mile peg on Albany Hwy [near Arthur R.], B.R.Maslin 2614 (CANB, PERTH).
Acacia ataxiphylla subsp. magna Maslin, Nuytsia 12: 324 (1999)
Spreading subshrub to c. 0.3 m high, with ascending to erect branches. Branchlets tomentulose and flattened or angled at extremities, glabrescent. Phyllodes somewhat coarse, mostly 40–60 mm long, infrequently 20–30 mm long, 1.6–2 mm wide. Peduncles 4–7 mm long, stout, 0.5–0.8 mm diam. (when dry), tomentulose; heads 7–9 mm diam. (when dry), c. 20-flowered; bracteoles 2–2.5 mm long. Calyx 3/4 to fully the length of the corolla; petals 2.5–3 mm long, nerveless or faintly flabellate-striate and lacking a central nerve.
Seemingly restricted to the Tammin area. Grows in sand over laterite in low heath.
May resemble some forms of A. stenoptera .
Type of accepted name
Tammin area [precise locality withheld for conservation reasons], W.A., R.J.Cranfield 1522a ; holo: PERTH.
W.A: type locality, M.D.Crisp 6595 (CANB, NSW, PERTH).