That family looks wicked, but that long abdominal process isn't a sting, it's an ovipositor (though in truth, the wasp's sting is a modified ovipositor -- think about that the next time you get nailed by a hot wasp!).

The ovipositor is rammed into the place where the eggs are to be deposited -- hence ovi (egg) -positor. I think that a lot of ichneumids parasitize their hosts during the maggot stage. The female female stabs the victim with her hypodermic ovipositor and squirts eggs into the host. The little darlings hatch and consume the host and pupate internally.

Cool, huh?

B