Found hunting rapidly through the leaf litter of a deciduous forest. Captured, with great difficulty, chilled, and posed, then released. Hunting behavior indicates it is a female. Body length is 24 mm. I've seen this wasp several times here in Durham, NC. Dorsal view of same individual shown in linked images.
This wasp sure looks like it could be the model for Mydas clavatus
, as the pattern is very similar: