Arge melanochroa is a species of the family Argidae, subfamily Arginae.

The adults grow up to 7–8 millimetres (0.28–0.31 in) long and can be encountered from May to July.

[1] The head, the antennae and the thorax are black, while the abdomen is reddish orange.

This species is very similar to Arge cyanocrocea, but in A. melanochroa the front wings have just a dark spot in proximity of the stigma, while the distal half (the apex) of the wings is transparent.

This sawfly can also be confused with Athalia rosae (Tenthredinidae), but in Arge melanochroa the antennae are composed of three sections, the third of which is greatly elongated, while in Athalia rosae the antennae are composed of 10–11 items.