Waspish Hoverfly

Size about 13mm. I call this fly Waspish Hoverfly because it behaves like a wasp. Its legs hang down during flight. I observed a few individuals slowly approaching our native bush with small leaves, cleverly navigating through the dense foliage. It never rested for long. At one stage, I observed one individual attacking a small Bee Assassin nymph 1st instar and also quickly dipped into a big lynx spider. I assume it is either predating on other insects that hide in the bush, or it is nesting in there. Its abdomen looks like it has a white extension adding to the wasp look. I have not looked into its identification. It could be a common species but it is certainly also a spring arrival.