Acacia sessilispica Maiden & Blakely, J. Roy. Soc. W. Australia 13: 23; pl. 16, figs 5- 10 (1928)
Spreading, rounded shrub 0.8– 2.5 m high. Branchlets slightly angular, glabrous, sometimes resinous. Phyllodes ascending to erect, slightly incurved, terete to slightly compressed, 5– 11.5 cm long, 1– 1.3 mm diam., acuminate, coarsely pungent with straight to subuncinate tip, rigid, glabrous, with 8 closely parallel nerves separated by deep furrows as wide as or wider than nerve-width. Inflorescences simple; spikes sessile, often tapering towards apex when in bud, 10– 28 mm long, 3– 5 mm diam., densely flowered, pale golden to dark golden; receptacle glabrous; bracteoles peltate. Flowers 4-merous; sepals free or rarely joined basally. Pods deflexed, linear, strongly and sharply raised over but not usually constricted between seeds, straight, to 7 cm long, usually 3– 4.5 mm wide, chartaceous, longitudinally wrinkled, glabrous. Seeds longitudinal, broadly elliptic to oblong-elliptic, depressed laterally, 3– 4 mm long, smooth, glossy, black; aril apical.
Occurs from Ballidu SE to Ravensthorpe with one collection from near Higginsville (c. 200 km NE of Frank Hann Natl Park), south-western W.A. Grows in granitic loam and sand, often near granite outcrops, mostly in shrubland and mallee communities.
Some collections from the southern end of the distribution range have narrower pods (c. 2.5 mm wide) somewhat constricted between the seeds but otherwise are apparently this species (e.g. c. 41 km ENE of Lake King, K.Newbey 6577 , PERTH) .
As discussed by R.S.Cowan & B.R.Maslin, Nuytsia 10: 45 (1995), A. sessilispica is closely related to A. multispicata which has phyllodes with 8- 20 nerves that are not separated by deep furrows, spikes in bud that are not apically narrowed, puberulous receptacles, broadly fan-shaped bracteoles, at least half-connate sepals and pitted and/or verruculose seeds. Also related to A. jibberdingensis . The phyllodes of A. sessilispica are similar to those of A. synoria and have a superficial resemblance to those of A. ephedroides , both of which are readily distinguished by their 5-merous flowers.
Type of accepted name
Bruce Rock, W.A., Aug. 1917, F.Stoward 163 ; lecto: NSW, fide R.S.Cowan & B.R.Maslin, Nuytsia 10: 44 (1995); isolecto: MEL, NSW (both incorrectly labelled ‘Kununoppin, Jan. 1917’), PERTH; Kununoppin, Jan. 1917, F.Stoward 69 ; paralecto: NSW.
Acacia multispicata Benth., Fl. Austral. 2: 400 (1864) p.p. , not as to lectotype, as to paralectotype, interior of south-west Australia, J.S.Roe s.n. (K, PERTH).
Acacia aciphylla var. leptostachys E.Pritz., Bot. Jahrb. Syst. 35: 306 (1904). Type: Jacup Ck, W.A., 8 Oct. 1901, L.Diels 4759 ; iso: PERTH (Fragment ex B).
W.A.: Wiacubbing Hill, 8 km due SE of Bencubbin, B.R.Maslin 1995 (AD, PERTH); 8 km from Hines Hill towards Nungarin, B.R.Maslin 2342 (CANB, K, PERTH); 14 km SE of Mt Gibbs, Frank Hann Natl Park, K.Newbey 6577 (CANB, K, MEL, PERTH); Wingarni Well, c. 40 km NNW of Norseman, K.Newbey 8573 (PERTH); Fitzgerald R. bridge on main road between Ravensthorpe and Jerramungup, M.D.Tindale 3832 (BRI, K, MEL, NSW, PERTH).