Ophraella sp..
 
 
 
Photo: 07/01/18, 3 pm.


Ophraella encompasses 14 species in the US. Their food includes flowers from the Asteraceae family (e.g., sunflowers). O. communa is my favorite because it is a successful biological control agent against ragweed. 
 

 
bug guide (these photos):
https://bugguide.net/node/view/1547505