As I mentioned earlier, I'm reading up on hymenopterans in preparation for setting up some kind of observational study of types and numbers of pollinators visiting prairie plants here. The "solitary" wasps are actually very cool - and they get a bad rap because really the stinging wasps that people hate so much are the "eusocial" wasps like yellow jackets and bald faced hornets. The solitary wasps are very much "good guys" of the garden because they catch and prey upon (or leave as a parisitoidized food for their young) caterpillars and other potentially damaging insects. (There are also spider wasps, which will attack spiders. They're supposed to have a nasty sting, if they do sting, but they're a lot less prone to because they are not defending a colony like the yellow jackets are.
Anyway, I saw one of these things in my yard this weekend and tried to guess what it was. My best guess is that it was a Cricket Hunter or one of the other Sphecid wasps. (I love that I can pick up that kind of terminology fast, and remember it - many insects are grouped based on their family assignment; Sphecid wasps are in the family Sphecidae. And they're one of the more common families of predatory solitary wasps.)
While flipping through my identification book to find it, I ran across two other good common names. (Someone with a sense of humor must have given common names to a lot of the insects. One of my favorites is the Pleasing Fungus Beetle. But I also like Confused Flour Beetle, even if I was a bit disappointed when I learned that it is called "Confused" because people confuse it with other species, and not because it is itself confused*)
But anyway. There is the Faithful Leafcutter Bee (We could almost put together a My Little Hymenopterans. She'd have to be the Applejack of the bunch.)
And there's the Progressive Bee Fly, which to me raises all kinds of questions about how they learned its political affiliation....
(*And my students NEVER LAUGH when I relay that story. Hmph.)