A pictorial key was developed as a training aid for the identification of the adults of 15 species of mosquitoes involved in the transmission of yellow fever virus in Africa. Included are 14 species of Aedes (subgenera Aedimorphus, Diceromyia and Stegomyia) and one species of Eretmapodites. Introductory figures display the taxonomic features used in the key.