Wow- this would have to be the coolest fly I've ever seen- wearing its sunglasses and showing off its shiny metallic sheen and polka dot attire! Observed on Eucalyptus botryoides in Lilli Pilli Bushland Reserve.
It was interesting to watch this trailcam video. The red-necked wallaby chased off the swampies, maybe because she has a joey, when it is normally the other way around.