The Aculeate Hymenoptera in particular. This excepts the massive Ichneumon group, the Gall wasps and the Chalcids. The possibilities for photos are massive. Though these are fast and wary beasts even when they are nectaring on flowers sometimes. The best time to shoot them is often when they are carrying prey or doing the digging as in this shot. The possibility of identifiable species in photos is becoming a bit less difficult at this time. I will attempt to add some more social wasp every change I get. And more of the flower bee species. See the first thumb for further info on this digging Ammophila.  Also keys for the Sphecid wasp genera are linked through the main Sphecid key here.