Isodontia apicalis or mexicana - Isodontia mexicana
Flatbush, Brooklyn (Kings County) County, New York, USA July 21, 2012
On Pycnanthemum, Mountain-Mint, in my garden.
Unsure of ID. Medium-sized (smaller than Sphex pensylvanicus, which was also present), all-black wasp, no noticeable iridescence, prominent white hairs, especially on thorax.