What makes it so easy to know it's not Vespidae and immediately ID it as Crabronidae or even Bembicini? Any particular feature? GISS or body shape?

As for wings, I posted two close-up crops, but I'm not sure if they'll be useful.

...are folded longitudinally when at rest. The wings on this specimen do not seem to display such a fold. As for placement in Gorytina... that's just based on overall appearance and a familiarity that comes from having looked at tens of thousands of bug photos. :)

Compare your specimen with this one:



I could be wrong, mind you. The additional photos still don't give a good view of the venation. But I'm fairly sure.

Please feel free to move the images back to Hymenoptera or Aculeata if you're doubtful.

I have no reason to doubt the ID, I just wanted to know how you did it so easily (since these black and yellow Sand Wasps appear to closely resemble Vespids on quick glance). Thanks for the longitudinal folded wings explanation. I was not aware that wings could be folded in that way. If I understand the folding mechanics, if this were a Vespid I would expect to see a straight edge (fold line) extending over the abdomen rather than the rounded edge of the full wing.

...showing one wing folded and one unfolded.