One of perhaps 3-4,ooo species of this family occuring in Australia. Its larvae feed as a parasite internally on other insects. On sunny days in summer the adults often rest on smooth Eucalyptus trunks and similar structures such as pipes and poles.
I.D. courtesy of Martyn Robinson. Naturalist. Australian Museum.
Further reading; http.www.brisbaneinsects. com/brisbane_flies/FlowerFeedingMarch.htm.
“Blowfly larvae feed on carrion and dung, which helps with decomposition. Adults feed on nectar and plant juices. Some are parasitic on earthworms and land snails. Some live in termite nests and ant nests”.
Further references and images : http.www.brisbaneinsects.com/brisbane_flies/Calliphoridae.htm