Acacia imparilis Maslin, Nuytsia 12: 358 (1999)
Erect or sprawling subshrub 0.2–0.7 m high. Stems slender and pubescent. Stipules linear to linear-triangular, 2–4 mm long. Phyllodes ascending to erect, inequilaterally narrowly oblong, oblong-elliptic, obovate or oblanceolate, mostly shallowly sigmoid, 6–16 mm long, 2–4.5 mm wide, subuncinate at the rostellate or obliquely narrowed apex, pungent, green, with indumentum as on branchlets except sometimes sparser, 1-nerved. Inflorescences simple, 1 per axil; peduncles 7–10 mm long, slender, glabrous; heads globular, 12–15-flowered, cream to pale yellow. Flowers 4-merous; sepals free; petals nerveless. Pods (immature) linear, shallowly curved, flat, to 5 cm long, 2.5 mm wide, red-brown, longitudinally nerved, strigulose. Seeds (immature) longitudinal, oblong, c. 5 mm long; aril terminal, conical.
Known from only two localities in the western extremity of the Stirling Ra. (E of Cranbrook), south-western W.A. Grows on rocky hills in open or closed Mallee scrub.
Phyllodes resemble some forms of A. ferocior (which also occurs in the Stirling Ra.) which can be distinguished by its 5-merous flowers and gamosepalous calyx; and A. huegelii which is distinguished by its normally 5-merous flowers which lack a calyx.
Type of accepted name
Hamilla Hill, 15 km due E of Cranbrook, W.A., 8 Oct. 1989, B.R.Maslin 6396 ; holo: PERTH; iso: CANB, K, MEL, PERTH.
W.A.: Mt Hamilla [Hamilla Hill], E.M.Canning WA/68 6156 (PERTH); south-west slope of Talyuberlup Peak, R.J.Cumming 1015 (PERTH).