Dejean A. auteur aut IRD Azemar F. auteur aut IRD Roux Olivier auteur aut IRD text journalArticle eng text/pdf born digital access In the Neotropics where it was introduced, the invasive ant Pheidole megacephala counterattacked raids by the army ants Eciton burchellii or E. hamatum. The Eciton workers that returned to their bivouac were attacked and spread-eagled and most of them killed by their outgoing colony mates. Little by little the zone where returning and outgoing Eciton workers encountered one another moved away from the Pheidole nest which was no longer attacked, so that most of the colony was spared. Using a water-based technique rounded out by bioassays, we show that Pheidole compounds were transferred onto the Eciton cuticle during the counterattacks, so that outgoing workers do not recognize returning colony mates, likely perceived as potential prey. Because P. megacephala is an introduced African species, this kind of protection, which cannot be the result of coevolutive processes, corresponds to a kind of by-product due to its aggressiveness during colony defence. specialized Army ants Antipredation Colony mate recognition Eciton Pheidole MEXIQUE 080 082 337 7-8 474-479 2014 1631-0691 https://www.documentation.ird.fr/hor/fdi:010062518 10.1016/j.crvi.2014.05.004 1631-0691 [F B010062518] https://www.documentation.ird.fr/hor/fdi:010062518 https://www.documentation.ird.fr/intranet/publi/2014/09/010062518.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2014-10-02 2017-08-23 fdi:010062518 fre