Petrophile pilostyla is a species of flowering plant in the family Proteaceae and is endemic to southwestern Western Australia. It is a shrub with needle-shaped, sharply-pointed leaves and spherical heads of hairy, cream-coloured or pale yellow flowers.
Petrophile pilostyla is a shrub that typically grows to a height of 0.4–1.7 m (1 ft 4 in – 5 ft 7 in) and has prominently ribbed, glabrous branchlets. The leaves are needle-shaped, sometimes strongly curved or s-shaped, 40–110 mm (1.6–4.3 in) long and 1–1.5 mm (0.039–0.059 in) wide with a sharply-pointed tip. The flowers are mostly arranged on the ends of branchlets in sessile, spherical heads 22–35 mm (0.87–1.38 in) in diameter, with narrow egg-shaped, glabrous involucral bracts at the base. The flowers are 9.5–17 mm (0.37–0.67 in) long, cream-coloured or pale yellow, and hairy. Flowering mainly occurs from July to early September and the fruit is a nut, fused with others in a more or less spherical head 10–20 mm (0.39–0.79 in) long in diameter.[2][3]
Petrophile pilostyla was first formally described in 2005 by Barbara Lynette Rye and Michael Clyde Hislop in the journal Nuytsia from material collected near Binnu in 2003.[2][4] The specific epithet (pilostyla) means "having a hairy style".[2][5]
In the same paper, Rye and Hislop described three subspecies and the names are accepted by the Australian Plant Census:
This petrophile is found on low hills where it grows in sandy-gravelly soils over limestone or laterite between Tamala Station near Shark Bay and Watheroo National Park in the Geraldton Sandplains biogeographic region.[2][3]
Petrophile pilostyla is classified as "not threatened" by the Western Australian Government Department of Parks and Wildlife[3] but subspecies syntoma is classified as "Priority Two" by the Western Australian Government Department of Parks and Wildlife[3] meaning that it is poorly known and from only one or a few locations.[9][10]
Petrophile pilostyla is a species of flowering plant in the family Proteaceae and is endemic to southwestern Western Australia. It is a shrub with needle-shaped, sharply-pointed leaves and spherical heads of hairy, cream-coloured or pale yellow flowers.