These are images of a male Wasp in the genus Eucerceris. Please note that the BugGuide does not have his species page listed, at this time and I'm prepared to request it now.
Using the document listed below, he appears to be a male Eucerceris canaliculata (Say) or E. pimarum Rohwer
Full Size Image: Click Here
Geographic Distribution = about 5 species possible in this area (central Arizona)
Here is relevant info from the key, (1975) found on the info tab for the genus Eucerceris: (tickle hairs, color & wide triangle)
From document: Bohart, Grissell: California Wasps of the Subfamily Philanthinae (1975)
From page 27: "In males of Eucerceris
, the development and distribution of apical hair brushes or fimbriae on the sterna offer convenient separational characters."
From page 29: "E. canaliculata
is a yellow & red wasp which is recognized in the male by the presence of prominent fimbriae on sterna 111-V of which that on V is shortened, but stretches across the middle third of the sternum. Also, the ocellocular distance is unusually great. "
From page 32: "E. pimarum
is the only extensively red species with weakly differentiated posteromedian hair tufts on sternum V in the male."
NOTES: The red arrow is pointing at his hairs or fimbriae
, on the sternal S4 segment.