Family

Fabaceae

Distribution

Discontinuous from the Moora–Wongan Hills area S to Augusta and Denmark, and E to the Stirling Ra., south-western W.A.

Description

Diffuse shrub to 2.3 m high; terminal branches commonly long, undivided and arching downwards. Branchlets finely yellow-ribbed, glabrous to shortly pilose or antrorsely puberulous. Stipules often spinose, 2–4 mm long, slender. Phyllodes ±patent, inequilateral, shallowly obdeltate to shallowly obtriangular with a prominent gland-bearing angle on adaxial margin, with adaxial proximal margin commonly convex and ±contiguous with branchlet and adaxial distal margin concave, 6–10 mm long, 3–8 mm wide, acuminate, pungent, normally glabrous; midrib prominent and near abaxial margin, often with an obscure second nerve. Inflorescences simple, 1 per axil; peduncles 3.5–10 mm long, slender, glabrous or sparsely puberulous; heads globular, 5–10-flowered, cream to pale yellow; buds ±obtuse. Flowers 4-merous; sepals c. 3/4-united; petals obscurely 1-nerved. Pods linear, curved, commonly twisted, to 7 cm long, 2–3 mm wide, ±thinly coriaceous-crustaceous, glabrous. Seeds longitudinal, ±oblong, 2.5–3 mm long, glossy, brown, arillate.

Habitat

Often grows near swamps and creeks but occurs also on drier sites in loamy laterite in Jarrah (Eucalyptus marginata) forest and, near Augusta, in sand over limestone in coastal heath.

Specimens

W.A.: 8 km S of Walebing, June 1932, W.E.Blackall s.n. (PERTH); Swan R., J.Drummond 2: 159 (BM, CGE, E, G, G-DC, K, LUND, MEL, NSW, OXF, P, PERTH); Stirling Ra., Chester Pass, B.R.Maslin 3769 (CANB, PERTH); 8.5 km S of Witchcliffe on Bussell Hwy, B.R.Maslin 3792 (K, PERTH).

Notes

Some field workers have suggested that A. scalpelliformis might be a hybrid between A. urophylla and A. divergens.

A member of the ‘A. biflora group’ with phyllodes closely resembling those of A. robiniae. Acacia divergens is the tallest member of the group and is distinguished by a combination of the following characters: heads 5–10-flowered and cream to pale yellow, peduncles 3.5–10 mm long, petals 1–1.7 mm long and obscurely 1-nerved, flower buds ±obtuse. See B.R.Maslin, Nuytsia 2: 302 (1978), for further details.

FOA Reference

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

Author

Minor edits by B.R.Maslin

B.R.Maslin