Acacia alleniana Maiden, in A.J.Ewart & O.B.Davies, Fl. N. Terr. 330; t. 26, figs A–G (1917)
Spindly, open shrub or tree to 5 m high; branches sometimes pendulous. Branchlets slender, with scattered lenticels, dark red-brown, glabrous. Phyllodes filiform, terete to quadrangular, 12–24 cm long, 0.5–0.8 mm wide, acute, not rigid, longitudinally sulcate when dry, puncticulate, glabrous; nerves not evident; gland obscure, 3–15 mm above pulvinus; pulvinus prominent, 1–2 mm long. Inflorescences simple; peduncles 2–6 per axil, 6–13 mm long, slender, glabrous; basal bract persistent; heads globular, c. 35-flowered, yellow; bracteoles exserted in buds. Flowers mostly 5-merous; sepals free, linear-spathulate. Pods linear, prominently raised over seeds alternately on each side, to 15 cm long, 3.5–5 mm wide, very thinly coriaceous, glabrous. Seeds longitudinal, oblong to elliptic, 4–5.5 mm long, 2–2.5 mm wide, turgid, ridged at periphery, dull, mid-brown, dark coloured bordering pleurogram; funicle filiform, scarcely arillate.
Occurs from near Darwin to Arnhem Land and islands of the Gulf of Carpentaria (Bickerton Is. and Groote Eylandt), N.T., SE to Westmoreland Stn in extreme north-western Qld. Grows in skeletal soil in hilly sandstone country.
Closely allied to A. jasperensis . Also related to A. juncifolia which differs by its broader, non-puncticulate, obscurely 4-nerved phyllodes (observe at x10 mag.), fewer heads per axil, non-exserted bracteoles in young buds and its mottled seeds.
Type of accepted name
Sandstone Ranges near Western Ck [1615’S, 13610’E], N.T., 16 Feb. 1911, G.F.Hill 776 ; holo: NSW; iso: K (sphalm. ‘10 Feb. 1911’), MEL.
Synonymy
Racosperma allenianum (Maiden) Pedley, Austrobaileya 2: 344 (1987). Type: as for accepted name.
Acacia tenuissima F.Muell., J. Proc. Linn. Soc., Bot. 3: 122 (1859), pro syn., non F.Muell., op. cit. 135, as to: near source of McArthur R., Gulf of Carpentaria, N.T., F.Mueller 5 ; K n.v. ( fide L.Pedley, Austrobaileya 1: 241, 1980), PERTH.
Illustrations
J.H.Maiden, loc. cit. ; J.Brock, Top End Native Pl. 55 (1988).
Representative collections
N.T.: 21 km N of Jim Jim Falls, Kakadu Natl Park, M.Lazarides 9077 (DNA); 29 km NE of new Tanumbirini HS, N.McHenry 9 (AD, PERTH). Qld: Westmoreland Stn, C.H.Gittins 828 (BRI).
(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.
