Yellow Hindlegged Wasp

Size 8mm. This wasp was found on our Callistemon tree, near the main stem. It behaved strangely, stayed in one place and seemed to use its ovipostor (portrait picture). The animal was shimmering in a blue-green thorax colour with a very dark base colour. Its head is heavily oval and pointed. Antennae are bent low near the base and most of the time pointing forwards and downwards. Narrow neck and waist. Ovipostor normal length about half abdomen size, bent upwards. Long legs that look extremely special. Heavily bent under body, joints yellow. Thigh thickened, spikes. Hind leg has a narrow white cover towards the back that looks unique. Taxonomically, it might be a Chalcid wasp, but I had no chance to investigate yet, also doubt that I will quickly find a result. Update 7/4/2017: The same species was found nearby on our Lilly Pilly bush. It stayed in one place for quite some time. It was putting its abdomen in the air. From far it looked like an ant fly, or actually an ant. The animal shows very characteristic hindlegs with yellow cover forward. I renamed this species from Callistemon Parasitic Wasp into Yellow Hindlegged Wasp. It is obvious that the wasp shows consistent characteristics other than being close to a Callistemon bush. I still could not place this wasp and doubt that I will succeed soon. Oh, I just noticed that this wasp has an ovipostor on the underside and a stinger on the back. Really should get myself informed on wasp anatomy.