Acacia pycnocephala Maslin, Nuytsia 2: 281; 280, fig. 6 & 326, fig. 20 (1978)
Erect or spreading shrub 0.3–0.6 m high. Branches orange to (reddish) brown. Branchlets puberulous with patent to slightly retrorse hairs. Stipules setaceous to narrowly triangular, 2–4 mm long. Phyllodes often crowded, patent to slightly reflexed, narrowly semi-trullate with a prominent gland-angle on adaxial margin near base, 6–11 mm long, 1.5–4 mm wide, acuminate, pungent with a 1.5–2.5 mm long cusp, rigid, olive green, glabrous, sometimes sparsely puberulous; midrib prominent, central; lateral nerves absent. Inflorescences simple, 1 per axil; peduncles 1.5–3 mm long, puberulous; heads globular, 4-flowered, golden. Flowers 4-merous; sepals 2/3–2/5-united, with lobes broadly triangular. Pods terete, abrubtly narrowed at both ends, curved, to 4.5 cm long, c. 3 mm diam., red-brown, striate, minutely puberulous. Seeds longitudinal, shape and size variable, oblong to elliptic, 3.5–4.5 mm long; aril terminal, conical.
Occurs from Narrogin to near Rocky Gully and E to Beaufort Inlet, also near Lake King, south-western W.A. Commonly abundant where it occurs. Grows in often lateritic sand or loam, in a variety of vegetation, but commonly Mallee shrubland or Wandoo woodland.
Distinguished from other members of the ‘ A. horridula group’ by golden flower-heads and rugose to verruculose seeds (seeds smooth in other members of the group). Closest to A. horridula which has much longer peduncles and less hairy pods.
Type of accepted name
19.5 km S of Lake King towards Ravensthorpe, W.A., 28 Aug. 1973, B.R.Maslin 3440 ; holo: PERTH; iso: CANB, K, MEL, N, LY.
Synonymy
Acacia horridula Meisn., in J.G.C.Lehmann, Pl. Preiss . 1: 9 (1844) and G.Bentham, Fl. Austral. 2: 350 (1864) p.p. , not as to lectotype, as to L.Preiss 965 (LUND, NY).
Illustrations
B.R.Maslin, Nuytsia 2: 280, fig. 6 (1978)
Representative collections
W.A.: Narrogin, C.A.Gardner 1496 (PERTH); 54.7 km S of Kojonup on road to Rocky Gully, B.R.Maslin 637 (CANB, PERTH); 6 km N of Mt Madden towards Lake King, B.R.Maslin 4063 (PERTH).
(BRM)
The information presented here originally appeared on the WATTLE CD-ROM which was jointly published by the Australian Biological Resources Study, Canberra, and the Department of Parks and Wildlife, Perth; it was produced by CSIRO Publishing from where it is available for purchase. The WATTLE custodians are thanked for allowing us to post this information here.
