Acacia rigens A.Cunn. ex Don, Gen. Hist . 2: 403 (1832); Benth., London J. Bot. 1: 342 (1842)
Needle Wattle , Nealie , Needle-bush Wattle , Nealia , Nilyah
Spreading shrub 2–3 m high, occasionally tree to 6 m high. Branchlets sericeous between the yellow ribs. Phyllodes straight to shallowly incurved, terete, rarely flat, 3–14 cm long, 0.8–1 mm diam., to 2.5 mm wide when flat, innocuous or coarsely pungent by a straight or curved point, coriaceous to subrigid, grey-green, multistriate by yellowish nerves (some appearing more prominent than others), appressed-puberulous or sometimes glabrous between the nerves; gland basal. Inflorescences simple, (1–) 2 (- 4) per axil; peduncles 2–6 mm long, appressed-puberulous; basal bract persistent; heads globular, 20–33-flowered, golden, resinous. Flowers 5-merous; sepals free to 1/2-united. Pods submoniliform, curved, 3.5–10 cm long, 2–3 mm wide, firmly chartaceous to thinly coriaceous, appressed puberulous. Seeds longitudinal, oblong-elliptic to narrowly elliptic, 3–4.5 mm long, glossy, pale brown; aril apical, conical.
Mainly found from the Gawler Ra., S.A., E through north-western Vic. to near Dubbo in N.S.W., but with a few scattered occurrences in western S.A., W.A. and Qld. Commonly in sandy soils but also in red and shaley soils, mostly in mallee scrub.
Often confused with A. havilandiorum . Similar in some respects to A. masliniana and A. roycei , both of which are readily distinguished by their subulate-pungent phyllode apices. Also superficially similar to A. argyrotricha . Acacia affin. rigens , a taxon of uncertain rank from south-west W.A. and presumably having affinities to A. rigens , is keyed and described separately in WATTLE. Another W.A. taxon of uncertain rank, previously regarded as A. rigens , is discussed under A. eremophila . Flat phyllode forms of A. rigens in S.A. are common in the Gawler Ranges where they appear to favour rocky hills.
Probably type of accepted name
Lachlan R., N.S.W., 1817, A.Cunningham 400 & 401 ; BM, K (cf. R.S.Cowan & B.R.Maslin, Nuytsia 12: 436–437 (1999) for discussion of typification).
Synonymy
Racosperma rigens (A.Cunn. ex Don) Pedley, Austrobaileya 2: 355 (1987). Type: as for accepted name.
Acacia chordophylla F.Muell. ex Benth., Linnaea 26: 612 (1855). Type: Murray R., Oct. 1848, F.Mueller s.n. ; lecto: MEL, fide L.Pedley, Austrobaileya 1: 186 (1978); isolecto: A, BM, K.
Illustrations
F. von Mueller, Iconogr. Austral. Acacia dec. 2 [pl. 4] (1887); J.H.Maiden, Forest Fl. New South Wales 3: pl. 114A (1908), 7: pl. 248A–K (1921); G.M.Cunningham et al ., Pl. W New South Wales 371 (1981); B.R.Maslin, in J.P.Jessop (ed.), Fl. Central Australia 119, fig. 158K (1981); D.J.E.Whibley & D.E.Symon, Acacias S. Australia 2nd edn, 217 (1992).
Representative collections
W.A.: 3.2 km E of Boorabbin on Great Eastern Hwy, B.R.Maslin 1859 (AD, K, MEL, NSW, PERTH). S.A.: c. 22.8 km SE of Tailem Bend on Dukes Hwy, N.Hall H80/85 (NSW, PERTH). Qld: Dingwall, 155 km SSE of Charleville, S.L.Everist 7508 (BRI). N.S.W.: 4.8 km NE of West Wyalong, R.Coveny 2377 (PERTH). Vic.: 4.8 km SE of Redcliffs, J.Cullimore 30 (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.
