See text Brachycistidinae is a subfamily of the flower wasp family Tiphiidae that contains 10 genera and 85 species,[2] and which is confined to the Nearctic zoogeographic region.

[3] These wasps demonstrate extreme sexual dimorphism; the females resemble ants and are wingless, while the males are winged and nocturnal.

[2] The taxonomy of the subfamily is difficult to resolve due to similarity of the structures of the species and their lack of distinctive colouration and patterning.

However, the males show a number of distinguishing characters in the structures of their genitalia, heads, thoraces, and the venation of their wings.

[5] The following genera are currently placed within the Brachycistidinae in two well-supported clades:[5] A phylogenetic analysis using females suggested a different phylogeny, but the true relationships of the genera in the subfamily will probably remain uncertain until a DNA based phylogenetic study can be undertaken.