Acacia yirrkallensis Specht, in R.L.Specht & R.L.Mountford, Rec. Amer.-Austral. Exped. Arnhem Land 3: 232, fig. 4 (1958)
Erect or prostrate, resinous shrub to 1 (–2) m high, branching near ground. Bark smooth, dark grey to dark brown. Branchlets angular, brown to dark red-brown or yellowish, glabrous; ridges often minutely resin-crenulated. Phyllodes very narrowly elliptic, narrowly elliptic-oblong to linear, straight to slightly curved, 1.5–4.5 cm long, 1.4–5.2 mm wide, thinly coriaceous, with prominent stomates, with 1 prominent main nerve, also sometimes 2 subprominent nerves, the minor nerves indistinct, parallel, sometimes sparingly anastomosing; gland basal, inconspicuous, 1–2 mm above pulvinus. Capitula 3–4.5 mm diam., yellow. Flowers 10–13 per head, 5-merous; calyx 0.9–1.1 mm long, almost free, glabrous; corolla 1.4–1.6 mm long, dissected to 1/3–1/2, glabrous; ovary glabrous. Pods oblanceolate to narrowly oblanceolate, basally narrowed, straight-sided, flat, 2–5 cm long, usually 4–9 mm wide, thinly woody, obliquely striate; margins and seed-partitions prominent. Seeds oblique, oblong-elliptic, 2.5–3.5 mm long, brown to dark brown; pleurogram with halo; areole elongate, open, dark brown; funicle-aril narrowly turbinate.
Occurs in northern N.T. in Arnhem Land N of Edith Falls (1411’S) and E to the Gulf of Carpentaria. Grows usually in grey sandy podsols on stony sandstone ridges and gorges, in eucalypt forest or woodland, also on laterite and bauxite. Flowers June–Jan.
A large pod variant (12–13 mm wide) occurs in inland sandstone areas, e.g. Russell-Smith 5223 & Lucas (DNA, PERTH).
A member of the ‘ A. stigmatophylla group’.
Type of accepted name
Gove, near Yirrkalla, N.T., 4 Sept. 1948, R.L.Specht 1016 ; holo: BRI; iso: CANB, NSW.
Illustrations
Specht et al ., loc. cit .; J.Brock, Top End Native Pl . 78 (1988).
Representative collections
N.T.: Wessel Is., P.K.Latz 3399 (BRI, CANB, MEL, NSW, NT); 3 km N of Yirrkala turnoff to Nhulunbuy road, D.Keith & B.Pellow 189 (NSW, SYD); Cato R., Arnhem Bay, F.Duncan (Cato 2) (NSW); c. 55 miles [88.5 km] W of B.H.P. Camp, J.R.Maconochie 1563 (BRI, CANB, DNA, MEL, NSW, NT, PERTH); c. 68 miles [109.5] km NE of Maranboy Police Stn, M.Lazarides & L.Adams 94 (BRI, CANB, K, NSW, NT).
(NSW)