A strange drama unfolded beneath the forest soil as an invading ant queen staged a silent coup, turning loyal ant workers into unexpected executioners. New research published on 17 November 2025 in Current Biology explores and details a remarkable infiltration strategy that reshapes scientific understanding of deception, survival, and power within eusocial insect societies.
Japanese Researchers Document How Socially Parasitic Ant Queens Induce Queen Matricide Chemically in Host Workers
Researchers documented a remarkable ant takeover in which an outsider queen manipulates a host colony through scent mimicry and a powerful chemical spray that turns worker ants against their own queen.
Invasion of a Parasitic Ant Queen
Researchers T. Shimada, Y. Tanaka, and K. Takasuka reported species of parasitic ant queens that use an advanced infiltration strategy that forces host workers to kill their own reproductive leader. These ants belong to Lasius orientalis and Lasius umbratus and infiltrate colonies of Lasius flavus and Lasius japonicus by mimicking the odor profile of the target hosts.
A parasitic ant queen begins its infiltration by contacting workers outside the host nest and acquiring the entire colony odor profile. Hence, with this chemical disguise, she can enter the interior chambers without triggering alarms. The ant workers treat her as part of the colony and allow her unhindered movement toward the central reproduction area.
Further, upon reaching the host queen, the invading parasitic ant queen repeatedly sprays her with a foul chemical fluid that researchers linked to formic acid. Note that this compound is produced by ants in the Formicinae subfamily of the ant family and is delivered through a specialized gland. The intense odor temporarily overwrites the normal colony scent signature.
The altered and unfamiliar scent causes ant workers to misidentify their reproductive leader as an intruder. This results in them attacking, killing, and removing the host queen from the nest. The parasitic queen remains in proximity but avoids retaliation by retreating during moments of worker aggression, then returning once the host queen has been eliminated.
Nevertheless, after the resident ant queen is removed, the parasitic ant queen assumes full control and reproductive authority over the colony. She begins laying eggs that receive complete worker care. All colony labor and resources shift toward the parasite bloodline, while the original lineage loses all future fitness potential. The invaded colony becomes fully redirected.
Matricide and Parasitic Ant Species
Researchers documented the entire sequence using video recordings that captured infiltration, spraying behavior, worker aggression, matricide, and takeover. Lead author K. Takasuka explained that the behavior represents a rare case of manipulation across species lines and noted its intensity compared with familiar fictional portrayals of forced succession.
Matricide, a behavior in which an offspring kills or consumes their mother, remains an uncommon phenomenon in nature. Moreover, although it appears maladaptive, this behavior can provide some advantages by boosting offspring survival through nutritional gain or by enabling offspring to redirect resources toward future reproductive investment.
Takasuka mentioned that two types of matricides have been recorded in nature, in which either the mother or the offspring benefits. However, in the documented case involving the parasitic ant queens, neither the mother nor the offspring benefited. The phenomenon has been framed as a third type of matricide induced by an invading outsider or third-party species.
Parasitic ants are a type of ant that exploits the social structure and resources of another ant species for its own survival and reproduction. They represent a diverse range of strategies and behaviors that all revolve around manipulating the host ant colony. One common behavior involves a parasitic ant queen directly killing the resident host queen.
Another behavior involves a parasitic colony of ant workers organizing raids on nearby colonies and stealing the pupae. The stolen pupae are then brought back to the home nest of the parasitic ants. When the pupae emerge as adults, they imprint on the parasitic colony and serve as slaves, carrying out tasks like foraging, nest maintenance, and even raising other pupae.
FURTHER READING AND REFERENCE
- Shimada, T., Tanaka, Y., and Takasuka, K. 2025. “Socially Parasitic Ant Queens Chemically Induce Queen-Matricide in Host Workers.” Current Biology. 35(22): R1079-R1080. DOI: 1016/j.cub.2025.09.037