Abstract: Chemical tactics by ant social parasites, including myrmecophiles, often relate to ant nestmate recognition and alarmcommunication. The strict nestmate recognition system in ants can be disrupted by chemical imitation of the nestmaterecognition pheromone, which consists of cuticular hydrocarbon components. Social parasites often acquire these components through direct body contact, but occasionally synthesize them even before ant adoption. Such an imitation ofthe host cuticular chemicals causes species-specific adoption of the parasites, which are then often taken care of by antsfor long terms. In contrast, transient invaders often use a propaganda allomone that induces panic alarm responses in ants.The allomone occasionally even causes fighting among nestmate ants, and seems to disrupt the ant nestmate recognition. These two chemical strategies are to modify the ant responses after ant detection. A third chemical strategy takenby some insect species is to avoid the detection itself, and is evidenced in the chemical phytomimesis by geometriid twiglike caterpillars. Since this counts upon the ants not to respond to the "invasion", it usually does not cause visible responses when it works effectively. Appropriate evaluation methods are necessary to evaluate the ant responses inducedby the parasites to reveal the underlying mimetic strategy.