Hymenopteran females are mostly highly selective, choosing their mating partner according to male quality signals, and may also signal their fertility through chemical advertisement. Male insects, in turn, often display a complex set of courtship behaviors to allure females to mate. In this study we explored the mechanisms triggering courtship behaviors in the oligolectic bee Heriades truncorum. In this species, males perform wing fanning followed by a sideways rocking motion before copulation. We tested the role of chemical cues in partner recognition by exposing males to dead females washed from cuticular extracts (i.e., sex pheromones) that were posteriorly coated, or not, with an extract of unmated females. Additionally, we experimentally reduced male wing length to test whether wing fanning was responsible for triggering sideways rocking motions. We found males to interact more often with females coated by extracts from unmated females, and to display wing fanning in the presence of these pheromones. Male wing fanning was important to perform sideways rocking motions, which are an essential behavior for successful mating and possibly an element used by females to evaluate male quality. Our study shows that both chemical and mechanical signals from female and male bees, respectively, are important elements in the mating system of H. truncorum.

膜翅目雌性大多具有高度选择性，根据雄性质量信号选择交配对象，并且还可能通过化学广告来表明其生育能力。反过来，雄性昆虫经常表现出一系列复杂的求偶行为来引诱雌性交配。在这项研究中，我们探索了寡聚蜜蜂Heriades trunco​​rum求偶行为的触发机制。在这个物种中，雄性在交配前先扇动翅膀，然后进行侧向摇摆运动。我们通过将雄性暴露于用角质层提取物（即性信息素）清洗的死亡雌性来测试化学线索在伴侣识别中的作用，这些角质层提取物的后部涂有或没有涂有未交配雌性的提取物。此外，我们还通过实验缩短了雄性翅膀的长度，以测试翅膀扇动是否会引发侧向摇摆运动。我们发现雄性更频繁地与涂有未交配雌性提取物的雌性互动，并在这些信息素存在的情况下表现出扇动翅膀。雄性翅膀扇动对于进行侧向摇摆运动非常重要，这是成功交配的基本行为，也可能是雌性用来评估雄性质量的一个因素。我们的研究表明，来自雌性和雄性蜜蜂的化学和机械信号分别是H. trunco​​rum交配系统中的重要元素。