Lasius orientalis and Lasius umbratus—invade and overtake a host ant colony. In both cases, the parasitic ant queen invades the nest and sprays the host colony queen with what is likely formic acid.

For some would-be ant queens, the easiest way to take over a colony is to dupe its worker ants into committing regicide.

Scientists say they have for the first time unlocked how a parasitic ant uses chemical warfare to take over the nest of a ...