The other comparably sized spider wasp found in California in this tribe (Aporini) is in the genus Psorthaspis. It is one of the dark Psorthaspis (P. planat) and is superficially similar to the western Aporus species. It's easy to tell them apart here in the east, the females have orange markings to one extent or another...Aporus never does. However, a difference between the two (in females) is the thickened front femur in Aporus (not so in Psorthaspis. The best difference between the two are the number of submarginal cells in the anterior wing (Psorthaspis with three, Aporus with two), but that character is rarely visible in photos because of how iridescent the wings are.