Acacia effusa Maslin, Nutysia 4: 85; 86, fig. 6 & 101, fig. 11 (1982)
Low, dense, resinous shrub to 1 m high. Bark ‘Minni Ritchi’, grey or greyish red. Branchlets terete, puberulous becoming glabrous with age. Phyllodes ascending, obliquely oblong-elliptic to narrowly elliptic (occasionally some phyllodes obovate to oblanceolate), (0.6–) 0.9–1.5 cm long, (2–) 3–7 mm wide, with indumentum as on branchlets, apically rounded with lateral +/- pungent mucro, with a prominent midnerve and a second longitudinal nerve running adjacent to the thickened adaxial margin (sometimes several subprominent nerves in wider phyllodes), the minor lateral nerves anastomosing longitudinally; gland 1, obscure, basal, 2–4.5 mm above pulvinus. Spikes 10–18 mm long, to 25 mm in fruit, bright golden. Flowers 5-merous, occasionally 4-merous; calyx 0.5–0.6 mm long, dissected to 1/2–2/3, glabrous; corolla 1.2–1.5 mm long, dissected to c. 1/2, glabrous. Pods flat but slightly raised over seeds, curved to once-coiled, sometimes twisted, to 8.5 cm long, 5.5–7.5 mm wide, coriaceous, glabrous. Seeds oblique, rotund to very broadly elliptic, 3–5 mm long, dark tan; areole small, closed, surrounded by pale halo.
Restricted to north-western W.A., collected only from within the Hamersley Ra. Natl Park, locally abundant. Grows in rocky red loam, on lower slopes particularly along creeks where the watercourses leave the hills. Flowers May–Sept.
Allied to A. lysiphloia , but the shrubs to 1 m high and the phyllodes asymmetrically elliptic, 9–15 mm long, 3–7 mm wide, with rostriform apices. These two species are also related to A. chisholmii , A. gracillima , A. trachycarpa and A. affin. trachycarpa .
Acacia daweana may have originated as a hybrid between A. effusa and A. hamersleyensis .
Type of accepted name
6 km N of Marandoo, on road to Tom Price, Hamersley Ra., W.A., 16 July 1980, B.R.Maslin 4681 ; holo: PERTH; iso n.v .: CANB, K, MEL.
Illustration
B.R.Maslin, op. cit. 86, fig. 6.
Representative collections
W.A.: 4.5 km along Mt Bruce road from Marandoo road, B.G.Briggs 8765 & L.A.S.Johnson (BRI, NSW, PERTH); 3 km W of Mt Bruce, C.G.Dawe 212 (PERTH); 6 km N of Marandoo on road to Tom Price, B.R.Maslin 5278 (NSW, PERTH); NE footslope of Mt Bruce, Pilbara region, R.Pullen 10.940 (NSW, PERTH).
(NSW)
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.
