Acacia triquetra Benth., London J. Bot . 1: 358 (1842)
Spreading, glabrous shrub to 1.5 m high. Branchlets acutely angled towards apices, ribbed below phyllode insertion. Phyllodes on obvious stem-projections, patent to erect but commonly inclined to ascending, narrowly oblong to oblanceolate or narrowly elliptic, rarely linear, straight or slightly curved, usually 10–25 mm long and 2–6 mm wide, l:w = 3–8, rounded-obtuse and excentrically rostellate, dark green; midrib not prominent; lateral nerves absent or obscure; gland adjacent to apical mucro, rarely few phyllodes with additional gland near middle. Inflorescences rudimentary 1-headed racemes with axes 0.5–1.5 mm long, 1–2 per node; peduncles 3–8 mm long, slender; heads globular, 10–18-flowered, golden. Flowers 5-merous; sepals free. Pods linear, straight to shallowly curved, to 6 cm long, 3–4 mm wide, firmly chartaceous. Seeds longitudinal, normally oblong, 2.5–3.5 mm long, slightly ridged peripherally, subnitid, dark brown; aril subterminal.
Occurs in S.A. on the Eyre Penin. from near Calca to Port Lincoln, Yorke Penin. S of Port Rickaby and on eastern Kangaroo Is. Grows in coastal sand and limestone, sometimes on sea cliffs or in swampy scrub and in mallee association.
Erroneously considered a Western Australian species by G. Bentham, Fl. Austral . 2: 354 (1864). The two Drummond specimens cited by Bentham under A. triquetra are A. meisneri .
A variant from Kangaroo Is. has unusually elongate phyllodes (23–38 mm long, 2–4 mm wide); typical A. triquetra also occurs on the Island.
A member of the ‘ A. microcarpa group’ (see B.R.Maslin, Nuytsia 6: 39, 1987) and formerly confounded with A. acinacea . Putative hybrids between A. triquetra and A. microcarpa occur on the Eyre Peninsula, S.A. Acacia imbricata is perhaps not specifically distinct from A. triquetra. Putative hybrids with A. paradoxa have been reported.
Type of accepted name
Probably Kangaroo Is., S.A., W.Baxter (sphalm. ‘King George’s Sound, Bagster’); lecto: K (fruiting specimen), fide B.R.Maslin, Nuytsia 6: 45 (1987); paralecto: K (flowering specimen).
D.J.E.Whibley & D.E.Symon, Acacias S. Australia 2nd edn, 65 (1992).
S.A.: c. 3 km N of Elliston, N.N.Donner 2430 (AD); c. 8 km SE of Bascombe Well HS, Eyre Penin., E.N.S.Jackson 1165 (PERTH); Formby Bay road area, southern Yorke Penin., 15 Sept. 1962, M.J.Hancock s.n. (AD); Bay of Shoals, Kangaroo Is., J.C.Noble 624 (AD).