Common Name

Yarnda Nyirra Wattle, Fortescue Wattle

Family

Fabaceae

Distribution

Occurs in north-western W.A., N of the Hamersley Ra. from Millstream (21º35'S, 117º04'E) and W of 122ºE, extending S to the northern Hamersley Ra.

Description

Compact, spreading, rounded or flat-topped, often multi-stemmed, resinous shrub 0.5–1 (–1.5) m tall and up to 2 m across. Bark smooth except at extreme base, ±grey. Branchlets terete, resin-ribbed at apices. Phyllodes curved at base to become ascending, ±terete, (1.5–) 2–4.3 cm long, 0.7–1.2 mm wide, glabrous, very obscurely 8-nerved; gland 1, obscure, basal. Inflorescences simple, axillary, bright yellow. Heads globular, dense, 7–10 mm diam., 30–45-flowered, resinous. Flowers 5-merous; calyx 1–1.3 mm long, dissected to 1/6–1/4, glabrous; corolla 2–2.5 mm long, dissected to c. 1/3, glabrous, viscid; ovary glabrous. Pods rigidly erect, linear-oblanceolate, straight, subterete to compressed, 3.5–5.5 cm long, 4–6 mm wide, woody, yellowish brown to dark brown, longitudinally nerved, glabrous, opening elastically from apex (valves recurved following dehiscence); margins not thickened. Seeds oblique, elliptic, 2.8–4 mm long, ±brown with slightly paler open areole; pleurogram with pale halo; funicle-aril straight, conical.

Phenology

Flowers Mar.–June.

Habitat

Appears to favour low rocky hills or stony flats, in spinifex dominated shrub-steppe.

Specimens

W.A.: Creek 3 at road, southern tributary of Fortescue [R.], 30 Jan. 1975, R.F.Black (NSW, PERTH); 13 km E of Dampier–Tom Price railway, on road to Wittenoom, B.R.Maslin 5567 (NSW, PERTH); ‘Palm Springs’ (tributary of Fortescue R.), 11 km W of Millstream Stn, A.Rodd 2809 (K, NSW, PERTH).

Notes

Related to the sometimes sympatric A. hilliana which has a similar growth form and phyllodes but which is readily distinguished by its spicate inflorescences and pods with thickened marginal nerves. Probably also related to A. arida and A. orthocarpa which are most readily distinguished by their spicate inflorescences and puncticulate phyllodes.

FOA Reference

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

Author

Edited by B.R.Maslin

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