Acacia viscidula Benth., London J. Bot. 1: 363 (1842)
Sticky Wattle
Shrub or small tree 1–6 m high. Branchlets angular, ribbed, resinous, usually puberulous. Phyllodes ascending, linear, incurved, 4–8 cm long, 1–3 mm wide, curved-acute to mucronate or apiculate, usually innocuous, thin, puberulous or glabrous, with 3–7 distant, impressed, resinous nerves and occasional anastomoses. Inflorescences simple, 1 or 2 per axil; peduncles 2–6 mm long, puberulous; heads globular, 4–5.5 mm diam., 20–35-flowered, light golden. Flowers 4-merous, infrequently 5-merous; sepals free to 1/2-united. Pods linear, raised over seeds, 7.5 cm long, 2.5–3 mm wide, puberulous. Seeds longitudinal, oblong, 4 mm long, glossy, dark brown; aril terminal.
Occurs principally in the Darling Downs in south-eastern Qld and adjacent N.S.W., extending inland in Qld to the Injune area and in N.S.W. to the Coonabarabran area. Found in upland granitic soils, in low woodland with Acacia and Eucalyptus species.
Bentham’s variety angustifolia , for which he cited no specimens, is said to be a narrow phyllode form with smaller flower-heads but the measurements given in his description fall well within the limits of the species for these characters. I have seen specimens (e.g. J.L.Boorman , NSW222567) from the Stanthorpe area of Qld that fit Bentham’s description but neither I nor L.Pedley, Austrobaileya 1: 204 (1978), have been able to locate authentic material.
Two collections from the vicinity of Torrington ( R.Coveny 2257 , NSW, PERTH and J.Vickery , NSW222570) are referable to this species but differ in having somewhat more rigid phyllodes which are rather pungent, as well as having flexuose-pilose branchlets and peduncles.
Similar in general appearance to A. cognata and A. subporosa , but probably most closely related to species of the ‘ A. wilhelmiana group’. Possibly related to A. elongata , but differing in having predominantly tetramerous flowers, at least in all the material I have seen, including the type. The species is described as ‘mostly 5-merous, but often 4-merous’ by G.Bentham, Fl. Austral . 2: 387 (1864).
Type of accepted name
Banks of the Lachlan R., N.S.W., C.Fraser ; holo: K; iso: PERTH (Fragment ex K).
Synonymy
Racosperma viscidulum (Benth.) Pedley, Austrobaileya 2: 357 (1987). Type: as for accepted name.
? Acacia viscidula var. angustifolia Benth., Fl. Austral. 2: 387 (1864). Type: not designated. Provisionally included here in synonymy in absence of having seen the type.
Illustrations
T.Tame, Acacias SE Australia 69, fig. 52, pl. 52 (1992).
Representative collections
Qld: 22 km SSE of Stanthorpe, 5 km N of Girraween Natl Park, R.S.& R.A.Cowan A-788 (BRI, CANB, K, MEL, NSW, PERTH). N.S.W.: 8 km WNW of Stannum towards Torrington, R.Coveny 2257 (NSW); [Coonabarabran area] near Backwater [Ck], 30 Oct. 1929, E.McKie & T.Youman (NSW).
(RSC)