Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, C.P. 6109, 13083-970 Campinas, São Paulo, Brazil.
Am Nat. 2010 Feb;175(2):261-8. doi: 10.1086/649580.
Predaceous ants are dominant organisms on foliage and represent a constant threat to herbivorous insects. The honeydew of sap-feeding hemipterans has been suggested to appease aggressive ants, which then begin tending activities. Here, we manipulated the cuticular chemical profiles of freeze-dried insect prey to show that chemical background matching with the host plant protects Guayaquila xiphias treehoppers against predaceous Camponotus crassus ants, regardless of honeydew supply. Ant predation is increased when treehoppers are transferred to a nonhost plant with which they have low chemical similarity. Palatable moth larvae manipulated to match the chemical background of Guayaquila's host plant attracted lower numbers of predatory ants than unchanged controls. Although aggressive tending ants can protect honeydew-producing hemipterans from natural enemies, they may prey on the trophobionts under shortage of alternative food resources. Thus chemical camouflage in G. xiphias allows the trophobiont to attract predaceous bodyguards at reduced risk of falling prey itself.
捕食性蚂蚁是树叶上的优势生物，对食草昆虫构成持续威胁。有人认为，吸食树液的半翅目昆虫的蜜露可以安抚好斗的蚂蚁，然后蚂蚁开始进行照顾活动。在这里，我们操纵冻干昆虫猎物的表皮化学特征，表明与宿主植物的化学背景匹配可以保护瓜亚基拉 Xiphias 树蜂免受捕食性 Camponotus crassus 蚂蚁的侵害，而不管蜜露的供应情况如何。当树蜂被转移到与它们化学相似性低的非宿主植物上时，蚂蚁捕食的情况会增加。可食用的蛾幼虫被操纵以匹配瓜亚基拉宿主植物的化学背景，吸引的捕食性蚂蚁数量比未改变的对照物少。尽管好斗的蚂蚁可以保护产蜜露的半翅目昆虫免受天敌的侵害，但在缺乏替代食物资源的情况下，它们可能会捕食营养共生体。因此，G. xiphias 中的化学伪装使营养共生体在降低自身成为猎物风险的情况下，能够吸引捕食性的保镖。
