Acupalpa is revised to include five described species: A. albitarsa Mann, A. divisa (Walker), A. pollinosa Mann, A. rostrata Kröber and A. semirufa Mann, and one new species, A. irwini sp. n. All species are brightly coloured wasp mimics with morphological and behavioural characteristics associated with mimicry of pompilid wasps. A key to genera and species is presented with male and female genitalia described and figured for the first time. All species of Acupalpa were compared in a cladistic analysis with two species of Agapophytus using 34 states across 16 adult morphological characters, which resulted in three most parsimonious trees (length = 58 steps). The phylogenetic relationships of species of Acupalpa are discussed in light of the analysis.