Common Name

Kimberley Ghost Wattle

Family

Fabaceae

Distribution

Occurs in the Kimberley region, W.A.; restricted to two populations c. 1 km apart in the Mitchell River Natl Park.

Description

Shrub 4–6 m high, wispy with open crowns, slender stems and pendulous branches and phyllodes. Branchlets pruinose, glabrous. Stipules caducous. Phyllodes filiform, quadrangular (when dry), not rigid, straight to shallowly incurved, 30–60 cm long, 1.5–2 mm wide, glabrous, green; with 4 yellowish longitudinal nerves; gland basal, sometimes a second gland near middle of phyllode. Inflorescences axillary or terminal racemes, or simple; raceme axes 2–8 cm long, glabrous; peduncles 1–3 in phyllode axils or at nodes along raceme, 10–18 mm long, glabrous; heads globular, large, 12–13 mm diam. when dry, densely 60–70-flowered, lemon-yellow; bracteoles linear-peltate, the laminae hispidulous with yellow hairs aging silvery. Flowers 5-merous; calyx gamosepalous, the short lobes and petals with indumentum as on bracteoles. Pods narrowly oblong, 11–15 cm long, 8–10 mm wide, coriaceous to slightly woody, openly reticulate, brown to reddish brown, glabrous. Seeds oblique, seated in shallow chambers, oblong-elliptic, 7–8 mm long, minutely pitted, brown; aril terminal.

Habitat

Grows in shallow sand associated with sandstone outcrops in mixed shrubland.

Specimens

W.A.: Kimberley region [precise locality withheld for conservation reasons], C.Done 1999 (PERTH); Seed from Kimberley region, cultivated in Darwin, 15 Feb. 2003, M.King (PERTH).

Notes

Related to A. kenneallyi which differs most obviously in broader phyllodes and smaller heads. Both these species referable to a group of north Australian acacias that also includes A. latescens, A. mimula and A. rothii, fide M.A.Lewington & B.R.Maslin, Nuytsia 19: 70 (2009), for discussion. Acacia aphanoclada from the Pilbara region, W.A., superficially resembles A. spectra in growth form and general phyllode morphology but is distinguished by having spinose stipules, smaller heads (7–9 mm diam. when dry), glabrous petals and thinly textured, narrower pods with longitudinal, shorter seeds. The north Australian species A. alleniana and A. jasperensis also have wispy growth forms and long, filiform phyllodes, but are not closely related to A. spectrum, fide M.A.Lewington & B.R.Maslin, loc. cit.

FOA Reference

Flora of Australia Project

Author

J.Reid, B.R.Maslin