Taxonomy, phylogeny and biogeography of ‘true’ francolins: Galliformes, Phasianidae, Phasianinae, Gallini; Francolinus, Ortygornis, Afrocolinus gen. nov., Peliperdix and Scleroptila spp.

Abstract

Afro-Asiatic perdicine galliform taxa commonly and inconsistently referred to as francolins, spurfowls and partridges have contentious taxonomic and phylogenetic histories. Hall combined two putative monophyletic, but taxonomically unnamed, clades comprising 28 perdicine species known as ‘francolins’ or fisante in South Africa and 13 more quail-like species (partridges or patryse) into a single genus Francolinus, which was the largest galliform genus. Furthermore, she partitioned fisante + patryse into eight, also formally unnamed, putative monophyletic ‘Groups’ and speculated on the phylogenetic affinities of four ‘Unplaced’ species. We investigate patryse sensu lato using combined morphological, vocalisation and DNA evidence to produce a comprehensive revision of patryse taxonomy and phylogeny, a stable classification system and common-naming practice, and hypotheses vis-à-vis eco-biogeographical processes that promoted their speciation and cladogenesis. We confirm the monophyly of a larger patryse clade (including members of Hall’s ‘Spotted Group’ and one ‘Unplaced’ species, gularis) both from her fisante, and propose that they should be referred to commonly as ‘francolins’. We recognise five genera in the following phylogenetic sequence: Francolinus, Ortygornis, Afrocolinus gen. nov. plus Peliperdix and Scleroptila. The proposed new system recognises 31 species, elevating 14 subspecies to species level (Ortygornis grantii, O. rovuma, Peliperdix dewittei, P. hubbardi, P. thikae, P. stuhlmanni, P. maharao, P. spinetorum, Scleroptila crawshayi, S. elgonensis, S. gutturalis, S. jugularis, S. uluensis and S. whytei) and lumping other subspecies into more inclusive entities. Biogeographically, Asio-African ‘true’ francolins sensu lato appear to have originated in Asia and/or Indonesia and were derived from a forest-adapted taxon. Within Africa, an early evolutionary radiation occurred in subdeserts and arid bush versus primary forest, culminating in Ortygornis spp. and Afrocolinus lathami. Thereafter, there was more complex evolution in savannas and grasslands along rainfall and altitudinal gradients. This radiation was further driven allo-parapatrically by topography, rainfall, dynamically expanding and contracting forests and Lake Mega-Chad.