Taxonomy
Until the early 1990s, major authorities placed all francolins in the genus Francolinus. In 1992 it was suggested that this treatment was problematic, and the francolins should be split into four genera: Francolinus for the Asian species, and the African species divided into Peliperdix, Scleroptila and Pternistis. The Crested Francolin and Nahan's Francolin were considered possibly quite distinct, but still maintained in Peliperdix and Pternistis respectively. Based on further evidence, the Crested Francolin was moved to the monotypic genus Dendroperdix in 1998, and the Nahan's Francolin was moved to Ptilopachus in 2006. Though some still maintain all these in Francolinus, the split into multiple genera is becoming more widespread. When split, the English name "francolin" is generally restricted to the members of the genera Francolinus, Peliperdix, Dendroperdix and Scleroptila, while the name "spurfowl" is used for Pternistis ("spurfowl" is also used for Galloperdix of the Indian subcontinent). As the Nahan's "Francolin" is related to the Stone Partridge rather than the true francolins and spurfowl, its name is sometimes modified to Nahan's Partridge.
In addition to the major changes proposed at genus level, the species level taxonomy among several francolins/spurfowl is disputed. For example, the distribution of the Orange River Francolin (F. (S.) levaillantoides) is highly disjunct, leading some authorities to split the northern taxa (from Kenya and northwards) into a separate species, the Acacia/Archer's Francolin (F. (S.) gutturalis, with subspecies lorti), while maintaining the southern taxa (from Angola and southwards) in the Orange River Francolin. Most authorities treat the Elgon Francolin (F. (S.) psilolaema elgonensis) as a subspecies of the Moorland Francolin, but others have suggested it is a species (F. (S.) elgonensis), a subspecies of the Shelley's Francolin, or even a hybrid between the Moorland and Red-winged Francolins.
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