Colour of the stripes ranges from grey to orange-yellow depending on the larval maturation environment.
Apparently most of the Melangyna (Melangyna) spp. in Australia (at least all those likely to be encountered in the ACT) are likely conspecific (yet to be published), so its probably ok to call all ACT Melangyna (Melangyna) spp. 'M. (M.) viridiceps' - which is the oldest name among these.