Rutenalid beetle, Anoplognathus porosus.
This genus is commonly referred to as Christmas Beetles, and the family come in a variety of shiny and metallic colours.
Larvae live underground, where they will also pupate, the adults all emerging at the same time. In Australia this is midsummer, explaining their common name, where they can be extremely common in some areas.
They feed on eucalyptus.
This individual photographed on the Lyrebird Walk, near the Mount Granya summit, Mount Granya State Park, Victoria.