Unknown Fly

Description:

At a glance this fly looked like a native bee of Exoneura genus, with its rounded red abdomen and black thorax, like in this spotting
http://www.projectnoah.org/spottings/101... A closer look revealed a fly head/antennae and halteres. The behaviour was also different from that of the bee, as it flew around the bush settling for only a few seconds.

Habitat:

Spotted on a tea-tree ( Leptospermum sp.) in a National Park on a very warm day.

Notes:

? Stratiomyidae
Order: Diptera