Sulphur Butterfly

From USFWS National Wildlife Refuge System:

Hide in plain sight! The cloudless sulphur butterfly almost looks part of the cactus bloom at Bosque del Apache National Wildlife Refuge, NM. The sulphur butterfly is a member of the Pieridae family, and can be bright yellow or orange with a wingspan of 2-3 inches. You can see them from southern Canada to Mexico, but not in the central or southeastern part of the U.S. 

Photo by Evi Rader, Student Conservation Association intern 
About Bosque del apache Refuge: www.fws.gov/refuge/bosque_del_apache/