The 11 species of Thyridanthrax Osten Sacken listed for the Afrotropical region are reviewed. Anthrax caffra Wiedemann is shown to be a species of Exoprosopa Macquart. T. calochromatus Bezzi, T. macquarti Bezzi, T. kappa Bowden and T. subperspicillaris Bezzi are reduced to subspecies of T. elegans Wiedemann, from the southern Palaearctic Region. T. idolus Hesse and T. speciosus Hesse are designated synonyms of T. perspicillaris hessei Bowden which therefore becomes a synonym of T. perspicillaris idolus Hesse. One new species, T. heliocheili sp. n. is described from specimens reared from Heliocheilus albipunctella (de Joannis) (Noctuidae) in Mali and Senegal. A key to the 11 species and subspecies now recognized is provided.