Isn't coincidence a marvellous thing?
Today I had a wonderful day in the Brisbane Ranges with the Field Nats Club - of which more later - and one of the photos I took was of an insect almost identical to that in the photo I posted yesterday of an unknown beetle on grass. This time I looked for some references to give me a name, and came up with Shield-bug (or Stinkbug) Poecilometis armatus. If attacked it can use a foul smell as protection. Luckily it didn't think my camera was a threat.