It is a solitary wasp with wingless females, Diamma bicolor, the so-called "Blue Ant", but not an ant at all!
The species belongs to the Hymenopteran family Tiphiidae, and there to the subfamily Diamminae which comprises but this one species.
The female hunts mole crickets. The cricket will be paralyzed by stinging, then the Diamma lays an egg on it. The larva slowly eats the paralyzed but still living mole cricket.
For humans the Diamma sting is very painfull and may be lethal for sensitive persons.
I know the species from NSW where I once have collected a specimen. Very impressive animal!
A question to Damian: May I use one of your pics for an article in our ant wikipedia?
Für deutsche Leser: Hier habe ich schon mal etwas zu Diamma geschrieben, im letzten post des threads:
http://www.antstore.net/viewtopic.php?t ... a&start=15
Regards,
Earlant