Petrophile linearis, commonly known as pixie mops,[2] is a species of flowering plant in the family Proteaceae and is endemic to southwestern Western Australia.

The flowers are arranged on the ends of branchlets or in leaf axils in sessile, oval to spherical heads up to 25 mm (0.98 in) in diameter, with many linear, tapering involucral bracts at the base.

Flowering occurs from August to November and the fruit is a nut, fused with others in an oval head about 25 mm (0.98 in) long.

[3][2] Petrophile linearis was first formally described in 1830 by Robert Brown in the Supplementum to his Prodromus Florae Novae Hollandiae et Insulae Van Diemen from material collected by Charles Fraser near the Swan River in 1826.

[6] Pixie mops grows in woodland and heath on the coastal plain and Darling Range from Jurien Bay and Eneabba to Yallingup.