Kin recognition, the ability to detect relatives, is important for cooperation, altruism and also inbreeding avoidance. A large body of research on kin recognition mechanisms exists for vertebrates and insects, while little is known for other arthropod taxa. In spiders, nepotism has been reported in social and solitary species. However, there are very few examples of kin discrimination in a mating context, one coming from the orb-weaver Argiope bruennichi. Owing to effective mating plugs and high rates of sexual cannibalism, both sexes of A. bruennichi are limited to a maximum of two copulations. Males surviving their first copulation can either re-mate with the current female (monopolizing paternity) or leave and search for another. Mating experiments have shown that males readily mate with sisters but are more likely to leave after one short copulation as compared with unrelated females, allowing them to search for another mate. Here, we ask whether the observed behaviour is based on chemical cues. We detected family-specific cuticular profiles that qualify as kin recognition cues. Moreover, correlations in the relative amounts of some of the detected substances between sexes within families indicate that kin recognition is likely based on subsets of cuticular substances, rather than entire profiles.

亲属识别，即检测亲属的能力，对于合作、利他主义和避免近亲繁殖很重要。对脊椎动物和昆虫的亲属识别机制进行了大量研究，而对其他节肢动物类群知之甚少。据报道，在蜘蛛中，裙带关系存在于社会和独居物种中。然而，在交配环境中亲属歧视的例子很少，一个来自圆球织布工Argiope bruennichi。由于有效的交配插头和性自相残杀率高，A. bruennichi的两性仅限于最多两个交配。在第一次交配后幸存下来的雄性可以与当前的雌性重新交配（垄断父权），或者离开并寻找另一个。交配实验表明，雄性很容易与姐妹交配，但与不相关的雌性相比，雄性更容易在短暂交配后离开，从而使它们能够寻找另一个配偶。在这里，我们询问观察到的行为是否基于化学线索。我们检测到有资格作为亲属识别线索的特定家庭表皮轮廓。此外，家族内某些检测到的物质的相对量的相关性表明，亲属识别可能是基于表皮物质的子集，而不是整个轮廓。