Family

Fabaceae

Distribution

Confined to the Pilbara region in north- western W.A. where it is seeming rare. It is known from the Hamersley Ra. W of Newman and near Wittenoom Gorge, and from near Nullagine.

Description

Dense, ±rounded sub-shrub 0.3–0.4 m high and spreading to c. 1 m across, slightly viscid, resinous and sometimes with a slight curry odour. Branchlets with rather dense, short, straight, spreading or slightly reflexed hairs. Phyllodes 5–15 phyllodes per whorl, rather wide-spreading to ascending, flattened to sub-terete, straight to shallowly incurved and sometimes slightly recurved at apices which are ±abruptly narrowed and possess a very short mucro, 3–8 mm long, c. 0.5 mm wide, indumentum similar to branchlets except hairs slightly shorter, dull greenish; longitudinal nerves indistinct. Peduncles 6–22 mm long, indumentum similar to branchlets. Heads 25–35-flowered, golden. Flowers 5- merous; calyx dissected into triangular lobes; petals obscurely striate, with sparse to dense, minute, spreading hairs. Pods (immature) 3–4 cm long, 8–10 mm wide, narrowly oblong, flat but rounded over seeds along midline, not constricted between seeds, straight to shallowly curved, sometimes slightly viscid, glabrous. Seeds (immature) transverse.

Phenology

Flowers July–Oct.

Habitat

Grows in skeletal soil on low rocky hills.

Specimens

W.A.: Wittenoom Gorge, E. Hall 1 (PERTH); c. 25 km W of Newman on road to Port Hedland, B.R.Maslin 8021 (CANB, MEL, PERTH).

Notes

In the field this putative hybrid is most readily distinguished from the parents by its dull greenish phyllodes which are intermediate in colour between the smoky blue-grey of A. adoxa var. adoxa and the bright green of A. spondylophylla. The phyllode length and orientation, the degree of resinosity and the petal striations are also intermediate between the parents. Plants of this hybrid sometimes have a faint curry odour (but not as strong-smelling as in A. spondylophylla). For further information see B.R.Maslin et al., Wattles of the Pilbara CD-ROM (2010).

The hybrid status of this entity is based on field observations and morphology of specimens examined; it occurs in populations (at low frequencies) with both presumed parents.

FOA Reference

Flora of Australia Project

Author

B.R.Maslin