Abstract: In the Chihuahuan, Mojave, and Sonoran deserts of the United States, mating flights of the seed-harvesting ant Pogonomyrmex rugosus Emery, 1895 are only known to occur in summer in response to seasonal rains. In parts of the Sonoran and Mojave deserts, however, summer rain is largely absent and most precipitation occurs during the winter and early spring. We observed a mating flight of P. rugosus at a western Mojave Desert location in late winter, four to six months earlier than reported for other areas. In this portion of their range, P. rugosus must either produce alates for summer flights and then over-winter them for late-winter to early-spring flights when summer precipitation is insufficient, or else they have fully converged on the mating-flight patterns of other desert species dependent upon winter and early spring rains.