This subfamily consists of the genera Agromyza, Japanagromyza, Melanagromyza, Tropicomyia, Ophiomyia and Hexomyza. Its monophyly can be established by the shape of the subcosta and wing vein R1: Subcosta well developed, coalescing with R1 before reaching Costa. R1 apically thickened, just before reaching the costa it is somewhat bent towards costal break agr-phy-wing.pct. This character is very useful as diagnostic feature too. There are hardly more characters which are constant throughout the whole subfamily. Most species are uniformly black, sometimes metallic; Surstyli are always fused with the epandrium. Other structures of the male genitalia and chaetotaxy are highly diverse.
The larvae can be recognized by the basal part of the cephalopharyngeal skeleton. The dorsal arm possesses a well-developed lower part agr-phy-larva.pct. In spite of this character all Agromyzinae show a variety of shapes. Examples are shown on the following picture: agromyzinae ceph.pct.
Agromyzinae contain leaf miners and - among others within the genera Melanagromyza, Hexomyza and Ophiomyia - many stem miners.