Neoprocris prunivora ?
Otero County, New Mexico
At the Chihuahuan Desert Garden at Oliver Lee Memorial State Park at the foot of the Sacramento Mountains (Dog Canyon), on May 23, 2012

I was thinking that it might be Gardinia anopla but Bruce Walsh pointed out that this looked too small  I am guessing a FW of 10 - 12 mm for this one. Other possibilities: Triprocris cyanea?

Looks like a nice fat female

images copyright Bob Barber