African Lemon-dove (Columba larvata) - HBW 4, p. 131

Taxonomy: Columba Larvata Temminck, 1810, Knysna, Cape Province.
A very specialized member of Columba, commonly placed in a separate genus, Aplopelia (see page 60). Forms a superspecies with C. simplex, with which usually considered conspecific, but differs markedly in voice; playback of voice to birds on Príncipe and African mainland elicited no response. Some authors have recognized the two species, but have placed all W African populations (and sometimes birds of race jacksoni) in C. simplex, retaining E & S African birds only in present species; populations of all Gulf of Guinea islands might be more appropriately placed in C. simplex; further investigation required, particularly for all W African populations. Much confusion and uncertainty too at subspecific level: birds of S Cameroon tend to be somewhat darker and have been awarded race plumbescens, but doubtfully valid; Liberian population poorly known, and subspecific assignment disputed; birds of Bioko and Pagalu have been awarded separate races, poensis and hypoleuca respectively; birds of mainland W Africa usually placed in race inornata, but with merging of Aplopelia in Columba this name becomes a junior synonym, and must give way to hypoleuca; should populations of Pagalu again be awarded separate subspecific status, mainland form will once again require renaming. Six subspecies tentatively recognized.