Atta mexicana
Nogales, Santa Cruz County, Arizona
Coordinates: 31.333231, -110.942530
June 17, 2018
Size: 16 mm (to tip of abdomen, not wings)
Found on a sidewalk in the city of Nogales, Arizona close to the international border with Mexico
A day after some of the first rains in the season
Determined by Salvador Vitanza
Confirmed by Steven Wang and James C. Trager