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A new genus and species of swan (subtribe Cygnina) are described here from the late Miocene deposits of Toros Menalla (Chad, Africa), which have yielded the earliest known hominid. Afrocygnus chativireae, gen. et sp. nov., is about the size of Cygnus atratus of the Australasian region, but differs morphologically from all living members of the genus Cygnus, and from all other extinct taxa of swans. Several extinct genera of swans or supposed extinct species of Cygnus actually appear not to belong to the Cygnini or to Cygnus, respectively, and should be revised. Afrocygnus chalivireae fills a biogeographical gap because there is no swan today in Africa except on the Mediterranean coast in winter, and the continent is now the only one-with Antarctica-lacking breeding swans. An unidentified swan is also represented in the Pliocene of Koro Toro (Chad). Remains previously identified as a goose-like member of Anserinae from the Mio-Pliocene boundary of Sahabi (Libya) are referred to Afrocygnits cf. A. chauvireae. Two records of a larger, unidentified swan are known in the early/middle Pleistocene of East Africa, but none for the southern part of the continent. Afrocygnus appears as the closest genus to Cygnus. The Chadian and Libyan swans indicate rather calm freshwater bodies in the vicinity of the deposits. Afrocygnus is indicative of some vertebrate endemism in the Chadian-Libyan area during the latest Miocene, in humid settings, through the incipient eastern Sahara desert.