Key to the species of Cyrtagenia from Brazil (modified from Evans 1973)

1 Swellings on the front well above the antennal sockets; some of the metasomal terga with lateral pale spots; pubescence fine and relatively inconspicuous.................................................................. A. fallax (Arlé)

- Front forming a nearly flat, oblique slope from the antennal sockets to the vertex; metasoma without pale spots; pubescence unusually coarse and hoary.................................................................. A. innuba Evans