The amount of red on the head in Polybia ruficeps is variable; the head is often less red in Paraguay and Argentina.
Photo data: 30 November 2012. Filadelfia, Boquerón department, Paraguay. This wasp was collecting fibers from a cactus spine.
GPS data: -22.347, -60.033. Elevation 139 meters.
Determined by Leopoldo Castro, Spain.