Square-headed Wasps, Sand Wasps, and Allies

The Crabronidae are a large paraphyletic group (nominally a family) of wasps, including nearly all of the species formerly comprising the now-defunct superfamily Sphecoidea. It collectively includes well over 200 genera, containing well over 9000 species. Crabronids were originally a part of Sphecidae, but the latter name is now restricted to a separate family based on what was once the subfamily Sphecinae. As this change is very recent, the subfamilies of Crabronidae likely will each eventually...