Data from: Dead ant walking: a myrmecophilous beetle predator uses parasitoid host location cues to selectively prey on parasitized ants

Myrmecophiles (i.e. organisms that associate with ants) use a variety of ecological niches and employ different strategies to survive encounters with ants. Because ants are typically excellent defenders, myrmecophiles may choose moments of weakness to take advantage of their ant associates. This hypothesis was studied in the rove beetle, Myrmedonota xipe, which associates with Azteca sericeasur ants in the presence of parasitoid flies. A combination of laboratory and field experiments show that M. xipe beetles selectively locate and prey upon parasitized ants. These parasitized ants are less aggressive towards beetles than healthy ants, allowing beetles to eat the parasitized ants alive without interruption. Moreover, behavioural assays and chemical analysis reveal that M. xipe are attracted to the ant's alarm pheromone, the same secretion used by the phorid fly parasitoids in host location. This strategy allows beetles access to an abundant but otherwise inaccessible resource, as A. sericeasur ants are typically highly aggressive. These results are the first, to our knowledge, to demonstrate a predator sharing cues with a parasitoid to gain access to an otherwise unavailable prey item. Furthermore, this work highlights the importance of studying ant–myrmecophile interactions beyond just their pairwise context.蚁栖生物（Myrmecophiles），即与蚂蚁形成关联的生物类群，依托多样的生态位并采用不同策略以应对与蚂蚁的相遇。由于蚂蚁通常具备极强的防御能力，蚁栖生物往往会选择蚂蚁处于弱势的时机，来利用其共生的蚂蚁伙伴。该假说在隐翅虫*Myrmedonota xipe*中得到验证：这类隐翅虫会在蚤蝇寄生蜂存在的场景下，与丝光阿兹特克蚁（Azteca sericeasur）建立共生关系。本研究结合实验室与野外实验发现，*M. xipe*隐翅虫会选择性定位并捕食被寄生的蚂蚁。相较于健康蚂蚁，被寄生蚂蚁对隐翅虫的攻击性更弱，这使得隐翅虫能够不受干扰地活食被寄生的蚂蚁。此外，行为学检测与化学分析结果显示，*M. xipe*会被蚂蚁的告警信息素吸引——而这类分泌物正是蚤蝇寄生蜂用于定位宿主的同一种分泌物。这一策略使得隐翅虫能够获取一种虽数量充沛但原本难以触及的食物资源，因为*A. sericeasur*蚂蚁通常具有极强的攻击性。据我们所知，本研究结果首次证实，捕食者可通过与寄生蜂共享信号线索，从而获取原本无法触及的猎物资源。此外，本研究还凸显了跳出两两互动的单一框架，开展蚂蚁与蚁栖生物相互作用研究的重要意义。