Common Name

Thiele’s Wattle

Family

Fabaceae

Distribution

Discontinuous along SW margin of the wheatbelt from near Toodyay S to Dardadine (c. 40 km due SW of Narrogin), south-western W.A..

Description

Grass-like, caespitose, multi-stemmed sub-shrub, erect and 20–50 cm tall or sprawling/scrambling ±prostrate. Stems gracile, little-divided, normally terete to sub-terete or quadrangular. Phyllodes continuous with stems, normally extremely reduced to ±terete, brown appendages 0.5–1.5 mm long, sometimes clearly-developed and superficially resembling stems, 2–33 mm long, 0.3–1 mm wide, erect, quadrangular to terete or ±compressed, subulate, 4-nerved with abaxial one the most pronounced, innocuous; gland absent. Inflorescences simple or 1- or 2-headed racemes 5–10 mm long; peduncles 5–15 (–23) mm long, glabrous; heads globular, 15–19-flowered, golden or cream-coloured; bracteoles 0.8–1 (–1.5) x 0.5–0.7 mm. Flowers 5-merous; sepals united, 2/5–1/2 length of petals; calyx tube glabrous, 1.3–1.5 mm wide at apex, truncate, repand or very shortly dissected into obtuse or broadly triangular, non-thickened lobes; petals glabrous and nerveless. Pods narrowly oblong, prominently rounded over seeds, 20–35 mm long, 4.5–6.5 mm wide, normally shallowly curved, glabrous or sparsely pilose, margins thickened. Seed transverse, 2–2.5 mm long, black, arillate, areole circular to elliptic.

Phenology

Aug.–Oct.; mature pods Dec.

Habitat

Occurs on laterite or sandy loam or sandy clay over laterite in lower shrub stratum of woodland often dominated by Eucalyptus accedens, E. drummondii, E. wandoo and/or Allocasauarina huegeliana.

Notes

Related to A. applanata which is distinguished by flattened, bifariously winged stems with the continuous phyllodes that are also flat, 1.5–5(–10) mm long and often appearing spur-like; it also has wider and normally densely villous pods, larger seeds and smaller bracteoles and calyces. See B.R.Maslin, Nuytsia 24: 148-149 (2014) for further discussion.

FOA Reference

Flora of Australia Project

Author

B.R. Maslin