The first formal description of the redthroat was by the English ornithologist and bird artist John Gould in 1841 under the present binomial name Pyrrholaemus brunneus.

[6] A small 11–12 cm (4.3–4.7 in) shy greyish-brown bird, the redthroat is most often seen swiftly darting through low branches and shrubs or hopping mouse-like on the ground.

Only adult males have the distinctive small, rusty-brown throat patch, which gives the species its common name and the absence of which makes the identification of females and juveniles more difficult.

[7] In New South Wales, the species is only known to occur in the far west, in several core populations, including Broken Hill, Tibooburra, Penarie and Nearie Lake Nature Reserve.

[7] The habitat of the redthroat consists primarily of arid and semi-arid regions of inland Australia, but it also occupies some coastal areas, as well as plains and rangelands.

[7] However, in some areas the species is known to occur in mallee with a diverse understory, semi-arid woodlands, Banksia and tea tree thickets and shrublands with an overstory of white cypress.

[9] The consistent feature among these habitats appears to be the presence of a complex understory, which provides suitable foraging and nesting resources for this shy, mostly ground-dwelling species.

Redthroats are omnivores with a diet consisting of seeds from grasses and shrubs as well as a broad variety of invertebrates, such as spiders, insects, and gastropods.

[10] This study found that redthroats feed mostly by pouncing on prey from the ground or gleaning in low vegetation, with very few instances of hunting on the wing.

Nests are located on or close to the ground among shrubs, grass tussocks, at the base of trees, in fallen logs or in small depressions.

The redthroat and the closely related speckled warbler are the only members of the acanthizids that have a solid coloured chocolate-brown egg.