This one was about 11mm long and almost as wide. Fairly solid too as it made loud crashing noises when hopping through the leaf litter.
In a small copse of eucalyptus with a thick ground cover of leaf and bark detritus.
Although I have found several Eurybrachidae nymphs I haven't seen an adult before.
Possibly Platybrachys decemmacula
Peter Chew has these described as 'Large Board-frons Planthoppers'
Lat: -37.95, Long: 145.26
Spotted on Jan 7, 2019
Submitted on Jan 8, 2019