The stone partridge (Ptilopachus petrosus) is a bird of the New World quail family. This largely brown bird, which commonly holds its tail raised, is found in scrubland and lightly wooded habitats, often near rocks, from Kenya and Ethiopia to Gambia (a large part of its range is in the Sudanian Savanna).
The stone partridge was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae. He placed it with all the other partridge like birds in the genus Tetrao and coined the binomial name Tetrao petrosus. Gmelin's description was based on the Comte de Buffon's "Le perdrix de roche ou de la Gambia" and John Latham's "Rufous-breasted partridge". The stone partridge is now placed with Nahan's partridge in the genus Ptilopachus that was introduced in 1837 by the English naturalist William Swainson. The genus name is from the Ancient Greek ptilon meaning "feather" with pakhus meaning "thick" or "dense". The specific epithet petrosus is Latin meaning "rocky".
Four subspecies are recognised: