Acacia undosa R.S.Cowan & Maslin, Nuytsia 10: 220 (1995)
Dense, domed or obconic shrubs 0.3- 1.5 m high. Branchlets tomentulose. Stipules persistent, subulate, to 2 mm long. Phyllodes spreading, linear to linear-oblanceolate, straight to shallowly incurved, 2–4.5 cm long, 1–4 mm wide, obliquely mucronate to subuncinate with a hard, innocuous to coarsely pungent point, rarely with a straight, sharply pungent point, rigid, glabrous except pulvinus tomentulose, with 9 plane or slightly impressed, close nerves per face, 20 nerves in all, with very occasional anastomoses, the internerve spaces with strongly raised stomata; glands 1 or 2. Inflorescences simple, 2 per axil; peduncles 1–1.5 mm long, glabrous; basal bracts cucullate, rostrate; heads globular, 3–3.5 mm diam., 18–20-flowered, golden. Flowers 5-merous; sepals free or to 1/2-united. Pods linear, strongly undulate, 1–4 cm long, 2.5 mm wide, crustaceous, papillate; marginal nerve distinct, much paler. Seeds longitudinal, elliptic-oblong to broadly oblong-elliptic, 2.2–2.7 mm long, dark brown; aril apical.
Known only from scattered localities from near Tammin and Bruce Rock S to Lake Grace and SE to near Lake King in south-western W.A. Grows in clayey sand or loam in open shrub mallee.
Several collections made between Tammin to c. 110 km NE at Warralakin (e.g. Survey camp, N of Warralakin, J.S.Beard 4735 , PERTH) have half-united sepals but in all other respects are referrable to this species.
A member of the ‘ A. densiflora group’ similar in several characteristics to A. hadrophylla . Specimens with very narrow phyllodes sometimes resemble A. densiflora but that species has tomentulose peduncles and non-undulate pods.
Type of accepted name
0.5 km S of Belka Siding (between Bruce Rock and Merredin), W.A., 14 Dec. 1971, B.R.Maslin 2361 ; holo: PERTH; iso: CANB, K, NSW.
Representative collections
W.A.: c. 0.4 km S of Belka Siding between Bruce Rock and Merredin, B.R.Maslin 1768 (AD, BRI, MO, PERTH); 36 km E of Lake King, K.Newbey 9476-1 (MEL, MELU, PERTH); 35 km S of Hyden towards Newdegate, R.Perry 545 (PERTH).
(RSC)
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.
