Family

Fabaceae

Distribution

Restricted to the vicinity of Oenpelli Mission, N.T.

Description

Shrub or tree to 4 m high, multistemmed, pruinose. Bark fibrous, dark grey. Branchlets terete except near apices, light brown, glabrous. Phyllodes semilunate, flat, straight or slightly curved, 1.5–4 (–5.5) cm long, (6–) 15–22 mm wide, coriaceous, glabrous, with 2–5 ±indistinct main nerves; minor nerves 6–8 per mm, fine, strongly anastomosing; gland 1, basal, to 1 mm above pulvinus. Spikes 3–4.5 cm long, golden. Flowers 5-merous; sepals free, 0.5–0.7 mm long, pubescent in lower half; corolla 1–1.2 mm long, dissected to 1/2, glabrous; ovary glabrous. Pods narrowly oblong, curved, 3.5–4.5 cm long, thickly coriaceous, glabrous. Seeds oblique, 3 mm long, black; pleurogram with halo present; areole open, pale; aril terminal.

Phenology

Flowers late June–late Sept.

Habitat

It is relatively common at the base of or on top of sandstone escarpments.

Specimens

N.T.: East Alligator R., N.Byrnes 913 (DNA, NSW, PERTH); WSW of Nabarlek, C.R.Dunlop 4973 (BRI, DNA, MEL, NSW, PERTH); 8 km SW of Oenpelli, J.R.Maconochie 1602 (DNA, NSW, PERTH).

Notes

Acacia mountfordiae is a member of the ‘A. tumida group’ but readily distinguished by its phyllode shape and size. It produces natural hybrids with another member of this group, A. difficilis, fide B.R.Maslin & M.W.McDonald (1996), A key to useful Australian acacias for the seasonally dry tropics 34 (CSIRO: Melbourne.).

FOA Reference

Data derived from Flora of Australia Volumes 11A (2001), 11B (2001) and 12 (1998), products of ABRS, ©Commonwealth of Australia

Author

Dr M.D.Tindale and Dr P.G.Kodela with the assistance of M.Bedward, S.J.Davies, C.Herscovitch, D.A.Keith and/or D.A.Morrison

Minor edits by B.R.Maslin & J.Rogers