The white-browed treecreeper (Climacteris affinis) is the smallest of the Australo-papuan treecreepers and sole family member adapted to arid environments. The species foraging strategy involves climbing the trunks of trees in search of invertebrate prey on and under bark. Although some populations within the species range have declined, the species IUCN conservation status is of Least Concern.
The white-browed treecreeper is 14–16 cm in length, has a wingspan of 22 cm and weighs 21g. Adult male plumage is mostly dark grey above (crown, neck, rump and uppertail) excluding the mantle and scapulars of which are brown and black sub-terminal tail-band. Facial plumage includes black lores, white tapered eyebrow and black and white streaked ear-coverts. The chin is white and throat brownish grey. The upper breast is grey and lower breast, belly, flanks and vent streaked black and white. Undertail coverts are barred black and white. Females are similar to males but with rufous stripe bordering the upper edge of the eyebrow and dull white streaking, tinged rufous, on the centre of the upper breast. In both sexes the bill is black, around 1.5–2 cm long and is relatively straight and slender. The iris is dark brown and legs and feet black. Juveniles differ from adults with pale grey bill and both facial patterning and ear-covert streaking duller and less distinct
The white-browed treecreeper has moderately long wedge shaped wings and square tail. Flight pattern over longer distances is undulated, involving brief bursts of flapping within long glides, during which a buff wingbar is visible.