The taxonomy of the Afrotropical footman moth genus Archithosia Birket-Smith, 1965 sensu lato is studied and two genus-group names previously considered as subgenera of Archithosia are upgraded to genus level (Acanthosia Krüger, 2015, stat. n. and Architesma Birket-Smith, 1965, stat. n.). The genus-group name Eurythosia Krüger, 2015 erected as a subgenus of Archithosia is synonymised with Architesma. A new genus, nineteen new species and a new subspecies are described: Flavifronthosia gen. n., Acanthosia tryphosa pringlei ssp. n., Acanthosia reducta sp. n., Acanthosia pervolgata sp. n., Acanthosia kruegeri sp. n., Asbolopsyche jiwundu sp. n., Asbolopsyche nyungwe sp. n., Asbolopsyche acanthosioides sp. n., Architesma frondosa sp. n., Architesma nyonie sp. n., Architesma nouabaleana sp. n., Architesma nkwaji sp. n., Architesma diffusa sp. n., Architesma ampullaria sp. n., Architesma bassa sp. n., Architesma turlini sp. n., Architesma odzala sp. n., Architesma ndoki sp. n., Architesma dolgomoides sp. n., Architesma smithi sp. n., and Architesma inermis sp. n. Twelve new combinations are introduced and one species-group taxon is downgraded to subspecies level: Acanthosia tryphosa tryphosa (Kiriakoff, 1958), comb. n., Acanthosia tryphosa duplicata (Birket-Smith, 1965), stat. & comb. n., Acanthosia similis (Birket-Smith, 1965), comb. n., Architesma makomensis (Strand, 1912) (= Eilema fuscicorpus Hampson, 1914), comb. n., Architesma angulifascia (Strand, 1913), comb. n., Architesma jaundeana (Strand, 1912), comb. n., Architesma henricus (Durante, Potenza & Pellegrino, 2024), comb. n., Architesma sordida (Birket-Smith, 1965), comb. n., Macrodicella derelicta (Debauche, 1942), comb. n., Flavifronthosia flavifrontella (Strand, 1912), comb. n., Hyleilema kinuthiae (Kühne, 2007), comb. n., and Coniopsyche gilvafrons (Durante & Panzera, 2002), comb. n. Adults, male and female genitalia are illustrated.