Although recognition using cuticular chemistry is important for host–parasite interactions within aculeate Hymenoptera, cuticular hydrocarbon (CHC) profiles of only a few host–parasite pairs were characterized and compared. One largely neglected family in this context is the Mutillidae (velvet ants), whose species are ectoparasitoids of bees and wasps. In our study, we characterized and compared the CHC profiles of five species of Mutillidae and seven host species. The CHC profile of velvet ants differed among species and included large proportions of n-alkanes and methyl-branched alkanes. Alkenes were much less abundant in the CHC profiles of three species of velvet ants compared with their hosts, while the other two species possess a much lower abundance of methyl-branched alkanes than their hosts. Both the number of peaks and compound diversity were generally higher in velvet ants compared with their hosts. Thus, CHC profiles of parasitoids did not show signs of mimicry when compared with their hosts. In dyadic encounters between one species of velvet ant and its host bee species, the parasitoid mainly avoided interacting, while aggression by the host was rare. Our results suggest that velvet ants did not evolve chemical mimicry, perhaps in accordance with their wide host spectrum which would limit chemical specialization. However, the reduction of alkenes in social bee-attacking species and the reduction of methyl-branched alkanes in social wasp-attacking species may favour host nest invasion, since these two CHC classes are known to be important in nestmate recognition for social bees and wasps, respectively. A larger, phylogeny-corrected comparison of Mutillidae and hosts may help clarifying the evolution of the CHC profile of these parasitoids.

尽管使用角质层化学进行识别对于有刺膜翅目昆虫中的宿主-寄生虫相互作用很重要，但仅对少数宿主-寄生虫对的角质层碳氢化合物 (CHC) 谱进行了表征和比较。在这种情况下，一个基本上被忽视的家族是 Mutillidae（天鹅绒蚂蚁），其物种是蜜蜂和黄蜂的外寄生物。在我们的研究中，我们描述并比较了五种 Mutillidae 和七种寄主物种的 CHC 配置文件。天鹅绒蚂蚁的 CHC 谱因物种而异，包括大部分n- 烷烃和甲基支链烷烃。与宿主相比，三种天鹅绒蚂蚁的 CHC 配置文件中烯烃的丰度要低得多，而其他两个物种的甲基支链烷烃的丰度远低于宿主。与其宿主相比，天鹅绒蚂蚁的峰数和化合物多样性普遍更高。因此，与其宿主相比，寄生蜂的 CHC 配置文件没有表现出模仿的迹象。在一种天鹅绒蚂蚁与其宿主蜜蜂物种之间的二元相遇中，寄生蜂主要避免相互作用，而宿主的攻击很少见。我们的研究结果表明，天鹅绒蚂蚁没有进化出化学拟态，这可能与其广泛的宿主谱相一致，这会限制化学专业化。然而，社会性蜜蜂攻击物种中烯烃的减少和社会性黄蜂攻击物种中甲基支链烷烃的减少可能有利于宿主巢穴入侵，因为已知这两个 CHC 类分别在社会性蜜蜂和黄蜂的同巢伴侣识别中很重要. 对 Mutillidae 和宿主进行更大规模的系统发育校正比较可能有助于阐明这些寄生蜂的 CHC 概况的演变。