This species (or perhaps a number of similar looking species) is seen quite commonly on the trunks of Red Gums in Woodlands Historic Park.
Classification
from Australian Faunal Directory
Order Hymenoptera - Wasps, Ants, Bees and Sawflies, 12202 named species in Australia
Family Pompilidae - Spider Eating Wasps, 268 named species in Australia
Genus Fabriogenia
Species ?