Full Metal Jacket

A Tachinid fly (I think, I'm certainly no expert on flies).

On beautiful Hartley Valley pink granite.

The larvae are maggots, and parasites, but allow their host to continue to feed and grow while they develop inside.

Nice.

Females are often seen flying quietly in search of hosts, whilst males may be seen resting on larger tree trunks, or even pink Hartley granite boulders, waiting for mates.

Like this bloke here.

Large, if you like.