The insect diversity in our yard has increased significantly each year since adding native plants.
My husband spotted this black and yellow wasp mimic just this weekend perched on some foliage.
It's actually a fly dressed like a parasitic wasp. A Xylomyid Fly (Xylomya terminalis), it lays eggs under bark or in wet wood where its larvae develop and "feed on the larvae of other insects" (Insects Their Natural History and Diversity). I would suspect that its larvae are parasitized by Ichneumon wasps.
Insects Their Natural History and Diversity)