Family

Fabaceae

Distribution

Occurs in the Witchcliffe–Augusta, Northcliffe–Walpole and Albany areas, south-western W.A.

Description

Sprawling or erect shrub, 0.3–0.6 m high. Branchlets sparsely antrorsely puberulous, hairs confined to ribs and commonly appressed. Phyllodes narrowly triangular, sometimes narrowly semi-trullate with a slight gland-angle on adaxial margin near base, pungent, cusp slender and c. 1 mm long, 5–9 mm long, 1–1.5 mm wide, ±patent, rigid, often distant, glabrous, green; midrib prominent and central; lateral nerves absent; stipules narrowly triangular to setaceous, erect, straight. Inflorescences simple, 1 per axil; peduncles 1–5 mm long, puberulous; heads globular to shortly obloid, 8–15-flowered, pale yellow to cream. Flowers 4-merous; sepals 1/2-united, with lobes triangular; petals glabrous, nerveless. Pods curved, terete, to 7 cm long, 2–3 mm diam., red-brown, striate, glabrous or subglabrous. Seeds longitudinal, ±oblong, 3–4 mm long; aril terminal, conical.

Habitat

In the Witchcliffe–Augusta area it grows on sand, sandy loam or lateritic loam in shallow depressions in open Jarrah–Marri (Eucalyptus marginata –E. calophylla) forest. Elsewhere it grows on loam in clearly defined, seasonal swampy areas.

Specimens

W.A.: near Karridale, on Margaret River–Augusta road, B.R.Maslin 474 (CANB, NSW, PERTH); 2 km N of Northcliffe towards Manjimup, B.R.Maslin 3785 (AD, BRI, G, K, PERTH, RSA).

Notes

Habit variable. In swampy sites within dense vegetation it is a sprawling shrub with long, weak, slender branches to 1 m long and as such it resembles A. inops. On drier, more open sites it is an erect shrub to 0.6 m high and with more rigid branches. Intermediate forms occur.

A member of the ‘A. horridula group’ most closely related to A. semitrullata.

FOA Reference

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

Author

B.R.Maslin

Minor edits by J.Rogers