This large wasp and several others were flying about and occasionally perched momentarily on two Sweetbush shrubs (Bebbia juncea--Asteraceae) on 23 Apr 2010 and were still flying about when we returned on 29 Apr. I am posting three images, which may be of the same wasp or three different wasps. The behavior of perching and patrolling seemed typical for males. They resemble Steniola wasps but seem to be larger than our other Steniolas and with a slightly different abdominal pattern.