Acacia ammobia Maconochie , J. Adelaide Bot. Gard . 1: 180; 181, fig. 1 (1978)
Shrub or small tree, 1.5–7 m high. Bark splitting longitudinally or fibrous, grey to black. Branchlets angular or flattened, soon becoming terete, pale yellow or light brown, glabrous. Phyllodes linear, flat, 11–27 cm long, 4–9 mm wide, tapered toward apex and base, the apex drawn out into an elongate, slender, blunt tip, coriaceous, with subprominent midnerve and 8–11 minor non-anastomosing nerves per mm; gland 1, very inconspicuous, basal, 1–3 mm above pulvinus. Spikes single or paired on axillary shoots that sometimes become leafy, 2–5 cm long, densely flowered, yellow. Flowers 5-merous; calyx 1–1.25 mm long, dissected to 1/10–1/5, basally villous, the lobes with orange-brown scurf; corolla 1.3–1.6 mm long, dissected to 1/3–1/2, glabrous; ovary densely villous. Pods linear, slightly constricted between and strongly raised over seeds, 5.5–11 cm long, 2–3 mm wide, the margins nerve-like, coriaceous, dark brown, glabrous. Seeds longitudinal, narrowly oblong to broadly elliptic, dorso-ventrally flattened, 3–4 mm long, dark brown; areole small, surrounded by pale U-shaped pleurogram; funicle folded and thickened into cupular aril.
Occurs in south-western N.T., in the vicinity of Ayers Rock, from 80 km W to 50 km E of Ayers Rock; also in far northern S.A. near Indulkana. Usually in sandy soils, often on dunes, or in gravelly soils, with spinifex. Flowers Aug.–Oct.
Allied to A. undoolyana .
Details of ecology, utilisation, etc. of A. ammobia are given in J.W.Turnbull (ed.), Multipurpose Austral. Trees & Shrubs 94 (1986). Details of the aboriginal use of this fire-sensitive rare plant are given by P.Latz, Bushfires & Bushtucker 86 (1995).
Type of accepted name
c. 30 km E of Ayers Rock, N.T., 1 Sept. 1972, J.R.Maconochie 1646A ; holo: DNA n.v .; iso: BRI, CANB, MEL, PERTH; all n.v .
Synonymy
Racosperma ammobium (Maconochie) Pedley, Bot. J. Linn. Soc . 92: 247 (1986). Type: as for accepted name.
Illustration
J.R.Maconochie, loc. cit .
Representative collections
N.T.: 31.1 miles [50 km] E of Ayers Rock, 14 Sept. 1956, G.Chippendale s.n . (CANB, NSW, NT); c. 30 miles [48 km] E of Ayers Rock, 28 Aug. 1980, R.Horner s.n. (NSW); 50 miles [c. 80 km] W of Ayers Rock, P.K.Latz 823 (NSW, NT); 39 km E of Ayers Rock, L.Ulyatt 121 (BRI, NSW, NT, PERTH). S.A.: upper slope of Indulkana Range, Anangu Pitjantjatjara Lands, P.J.Lang & P.D.Canty BS23-29140 (AD).
(NSW)