In social insects, chemical communication is the main communication mode among colony members, which use the blends of cuticular hydrocarbons as recognition cues to discriminate between nestmates and non-nestmates and to prevent the exploitation of their nest resources by aliens. The aim of this study was to assess the variation of nestmate recognition cues in the ant Ectatomma ruidum, a species complex with a considerably conserved morphology and one of the few ant species where intraspecific thievery, a form of cleptoparasitism, has been reported. We analyzed the cuticular hydrocarbon profiles of ants collected from a number of geographically separated populations and examined DNA sequence data to assess their species identity. We focused on one species of the complex, E. ruidum sp. 3–4, whose species delineation remains controversial. We documented that several quantitative and qualitative traits of the cuticular hydrocarbon profiles varied significantly between populations, indicating that this species harbors more cuticular chemical phenotypic diversity than expected within a single species. In particular, there was a striking divergence among populations in the proportion of methylalkanes, alkenes, alkadienes and odd-chain components, which likely play a major role in nestmate/non-nestmate discrimination, a process which might have been crucial in these cleptobiotic ants. Further investigations are needed to test the hypothesis that biotic pressures, such as the need to discriminate conspecific intruders and limit thievery, could have played an important role in promoting the evolutionary divergence between populations in this ant species complex.

在社会昆虫中，化学交流是群体成员之间的主要交流方式，它利用表皮碳氢化合物的混合物作为识别线索，以区分巢穴和非巢穴，并防止外星人利用其巢穴资源。这项研究的目的是评估蚂蚁Ectatomma ruidum（一种具有相当保守的形态的物种复合体，是少数物种物种，其中报道了种内通透性，是一种裂唇草）的巢伴侣识别线索的变化。我们分析了从许多地理上分离的种群中收集的蚂蚁的表皮碳氢化合物概况，并检查了DNA序列数据以评估其物种同一性。我们专注于一种复杂的物种，即大肠埃希菌sp。3-4，其物种划分仍然有争议。我们记录到，不同种​​群之间的表皮碳氢化合物分布图的几个定量和定性特征显着不同，这表明该物种的表皮化学表型多样性比单个物种更高。特别是，人群之间甲基烷烃，烯烃，链二烯和奇数链组分的比例存在显着差异，这可能在巢式/非巢式歧视中起主要作用，这一过程在这些亲脂性蚂蚁中可能至关重要。需要进一步的研究来检验生物压力的假设，例如区分同种入侵者和限制入侵者的需求，