The Black-Cheeked Lovebird was one of the last parrot species in Africa to be formally described by Western science. It was not until 1906 that the British ornithologist Philip Sclater published the first scientific description of the species, assigning it the binomial name Agapornis nigrigenis, a reference to the distinctive dark feathering on its cheeks and face. The discovery came relatively late in the era of African ornithological exploration, largely because the species occupies a narrow and remote range in what was then Northern Rhodesia, an area that did not attract the same volume of naturalist expeditions as the coasts or the East African highlands.
The first specimens to reach European collections were procured from the Kafue River region and the upper Zambezi watershed in what is now southwestern Zambia. These early skins revealed a small, compact lovebird with predominantly green plumage, an orange-red bib across the upper breast, and the dark brownish-black facial patch that gives the species both its common and scientific names. Taxonomists immediately noted its resemblance to Lilian's Lovebird and the closely related Nyasa Lovebird group, and debate over its precise phylogenetic placement within the Agapornis genus persisted for decades.
Field naturalists who followed Sclater into the Kafue Flats and the surrounding mopane woodlands confirmed that the species was highly localized, tethered to areas where permanent surface water and mature deciduous trees coincided. This dependence on a specific habitat mosaic explained why earlier collectors had missed it entirely and why subsequent surveys continued to find it restricted to a modest geographic footprint. The combination of late discovery and limited range set the tone for much of the species' subsequent history.
The description of Agapornis nigrigenis added a ninth recognized species to the Agapornis genus, filling a distributional gap in the southern African radiation of lovebirds. Its discovery also underscored how much avian diversity remained undocumented in the interior of the continent well into the twentieth century, a reminder that the cataloging of African birdlife was far from complete even during the heyday of museum-based ornithology.