In a groundbreaking discovery, researchers have identified a unique parasitic ant species in Japan that has effectively eradicated both male and female worker ants from their colonies. This means that all individuals in these colonies function as queens, attempting to dominate the nests of competing species.

Typically, ant colonies are structured with a queen, female workers, and short-lived males that die shortly after mating.

For over four decades, scientists have speculated about the existence of this elusive parasitic ant, Temnothorax kinomurai, which is known to produce only queens. Until now, however, there was no definitive proof.

Young queens of this parasitic species infiltrate the nests of closely related ants, Temnothorax makora, killing the host queen and some workers through stinging. They then reproduce asexually, creating cloned offspring in a process called parthenogenesis—a phenomenon that is rare among ants but common in other insect species. As a result, workers from T. makora are deceived into nurturing the young kinomurai queens.

Research led by Jurgen Heinze and his team at the University of Regensburg, Germany, successfully bred and raised T. kinomurai queens in a controlled laboratory environment, resulting in 43 queen offspring—none of which displayed male reproductive organs.

The resulting 43 queens were then introduced to colonies of T. makora. Out of these, seven queens survived and successfully executed their takeover, producing 57 additional offspring, all confirmed to be female queens.

“This discovery reveals a completely new form of social organization among ants, adding a fascinating dimension to the already complex world of ants,” Heinze states.

While invading the colonies of other species can be a precarious tactic—evidenced by the study’s high queen failure rates—having an all-female offspring increases the likelihood of establishing a new reproductive colony.

“If parthenogenesis arose through random mutation, this is the outcome. A single T. kinomurai queen can produce 100 daughters without the need for mating, leading to 100 queens ready to seek out new colonies,” Heinze explains.

“This species represents the pinnacle of social parasitism evolution, showcasing the remarkable adaptability in the life cycles of social insects,” he concludes.