Acacia crassiuscula H.L.Wendl., Comm. Acac. Aphyll . 5, 31, t. 8 (1820)
Shrub 1–2.5 m high, often spindly. Branchlets glabrous. Phyllodes ascending to erect, linear, rarely terete, straight to shallowly incurved, 5–10 cm long, (1–) 2–4 mm wide, narrowed at base, obtuse to acute, mucronulate, with mucro sometimes pungent, thick, somewhat rigid, longitudinally rugose, dark green, glabrous; midrib rather prominent; gland 2–8 mm above pulvinus. Racemes 1–6 cm long, 3–8-headed, glabrous; axis flexuose; peduncles 4–8 mm long, constricted at receptacle; heads globular, 5.5–6 mm diam., 13–20 flowered, cream; buds often subacute. Flowers 5-merous; calyx gamosepalous. Pods linear, shallowly constricted between seeds, 10 cm long, 4–5 mm wide, thinly coriaceous, glabrous; marginal nerve narrow, yellow. Seeds longitudinal, oblong to elliptic, 4.5–4.8 mm long, semi-glossy, black; aril terminal, thick.
Found in near-coastal areas from Albany E to Cape Arid Natl Park, W.A., also two discontinuous collections from north and NW of Walpole, c. 100 km W of Albany. Grows in association with granite, often in white, granitic sand, sand over quartzite and rocky sand in scrub mallee and heath.
The nomenclature of A. crassiuscula is complicated and is discussed by L.Pedley, Austrobaileya 1: 286 (1980). In Fl. Austral. 2: 372 (1864), G.Bentham misapplied the name to several taxa, including A. hamiltoniana , viz. Sieber 464 while at the same time describing true A. crassiuscula as A. pycnophylla ; he also erroneously treated A. adunca as conspecific with A. crassiuscula .
Plants with narrow phyllodes (1–1.5 mm wide, sometimes quadrangular-terete) occur mainly E of Esperance. G.Bentham applied the name A. pycnophylla var. angustifolia to these but the variant is not considered worthy of formal rank.
Superficially resembles A. cupularis which is a glabrous shrub, phyllodes with 2 or 3 glands, much shorter racemes with fewer, golden flower-heads on generally shorter peduncles that are not constricted at the receptacle and more or less submoniliform pods. Sometimes confused with A. harveyi which has uncinate phyllode-tips, smaller heads and the aril half or more encircling the seed. In phyllode shape and size, resembling A. euthyphylla .
Type of accepted name
‘Habitat in Nova Hollandia’; holo: GOET—folder annotated by H.L.Wendland ‘Acacia crassiuscula Wend.fil.’; iso: MEL.
Acacia pycnophylla Benth., Fl. Austral . 2: 368 (1864). Type: Swan R., W.A., J.Drummond 3: 98 ; syn: K; isosyn: FI, G, MEL, OXF, P, TCD; King George Sound, W.A., A.Oldfield s.n .; syn: K; isosyn: MEL; Swan River [Princess Royal Harbour, 27 Sept.1840—cf. LUND, NY isotypes], L.Preiss 929 ; syn: K; isosyn: FI, C, G, GOET, HBG, L, LUND, M, MEL, MO, NAP, NY, P, PERTH, RO, STR.
Acacia pycnophylla var. angustifolia Benth., loc. cit. Type: Cape Pasley (sphalm ‘Paisly’), W.A., G.Maxwell s.n. ; syn: K; isosyn: MEL, PERTH; Cape Le Grand, W.A., G.Maxwell s.n .; syn: K; isosyn: MEL, PERTH.
H.L.Wendland, loc. cit.
W.A.: Whoogarup Ra., Fitzgerald R. Natl Park, M.I.H.Brooker 2746 (MEL, NSW, PERTH); Granite Peak, c.32 km N of Walpole, A.S.George 11121 (MEL, PERTH); Cape Arid Natl Park, A.S.Weston 9684 (PERTH).