The Madagascan fauna of the genus Curtonotum Macquart, 1844 is reviewed. Type material of the seven species described by Tsacas in 1974 (C. balachowskyi, C. boeny, C. keiseri, C. pauliani, C. sakalava, C. sternithrix and C. stuckenbergi) was studied and additional material of five of these is noted, substantially increasing their known distributions. Six of the seven species described by Tsacas are endemic to Madagascar; unpublished records indicate, however, that C. pauliani, occurs in Namibia and South Africa on the African continental mainland. Six additional endemic species are described as new: C. coronaeformis sp. n., C. gladiiformis sp. n., C. griveaudi sp. n., C. irwini sp. n., C. parkeri sp. n., and C. rinhatinana sp. n. The head and thorax, frons, wing, sixth sternite and hypandrium of the male of the 13 species are illustrated for the first time, as well as the highly diagnostic male phallus, both laterally and dorsally at the junction of the basiphallus and distiphallus. A key to species based on male characters is provided, and species distributions are mapped and interpreted. The biogeographical significance of the Madagascan species is discussed. An annotated checklist of Madagascan Curtonotidae is presented, and co-ordinates used to plot maps and a list of vegetation types in which species occur are provided.