The mating beetles were on a twig that had fallen into a wattle bush and was protruding from it. The beetles had pollen grains on them presumably from the adjacent wattle. A challenge to photograph as the two beetles together were smaller than a match-head.
Hi Tim Thanks for this interesting little beetle. The "Associated plant" field is there for when you know the name of the plant the insects are feeding or resting on. This can be very helpful because some insects can be identified from the plant they like best. I have shifted your comment, which was in the Associated plant field, in with your other comments. Regards Michael