Talukder Mohammad Belal, Müller Carsten H G, Zhang Dan-Dan, Schulz Stefan, Löfstedt Christer, Wang Hong-Lei, Uhl Gabriele B
General and Systematic Zoology, Zoological Institute and Museum, University of Greifswald, Greifswald 17489, Germany.
Pheromone Group, Department of Biology, Lund University, Lund 22362, Sweden.
Proc Natl Acad Sci U S A. 2025 Jan 21;122(3):e2415468121. doi: 10.1073/pnas.2415468121. Epub 2025 Jan 6.
The sense of smell is a central sensory modality of most terrestrial species. However, our knowledge of olfaction is based on vertebrates and insects. In contrast, little is known about the chemosensory world of spiders and nothing about how they perform olfaction despite their important ecological role. The orb-weaving spider lends itself to an in-depth study on olfaction as it is one of the few spider species whose volatile sex pheromone, emitted by females to attract males, is known. We combined ultrastructural and electrophysiological analyses and found that previously overlooked sensilla with wall pores are abundant on all walking legs of males. We compared the ultrastructure of these wall-pore sensilla with those known to perform olfaction in insects, exploring similarities and differences. Electrophysiological single sensillum recordings demonstrated that the wall-pore sensilla in respond highly sensitive and in a concentration-dependent manner to the sex pheromone. Our study demonstrates male-specific sensilla for detecting signaling females, whereas females and subadult males are devoid of wall pore sensilla. In a preliminary comparative morphological analysis using 19 species from 16 spider families, we found that wall-pore sensilla occur in male spiders from most, but not in basally branching clades or in Salticids, suggesting that wall-pore sensilla evolved at least once within spiders and were lost at least once. This research significantly expands our knowledge of the sensory ecology of spiders, will stimulate studies on the diversity and function of sensilla, as well as studies on the evolution of olfaction in arthropods.
嗅觉是大多数陆生物种的一种主要感官方式。然而，我们对嗅觉的了解基于脊椎动物和昆虫。相比之下，对于蜘蛛的化学感应世界知之甚少，尽管它们具有重要的生态作用，但对于它们如何进行嗅觉感知却一无所知。圆网蛛适合进行嗅觉的深入研究，因为它是少数几种已知雌性会释放挥发性性信息素以吸引雄性的蜘蛛物种之一。我们结合了超微结构和电生理分析，发现雄性蜘蛛的所有步足上都大量存在以前被忽视的有壁孔的感觉毛。我们将这些壁孔感觉毛的超微结构与已知在昆虫中执行嗅觉功能的感觉毛进行了比较，探索它们的异同。电生理单感觉毛记录表明，雄性圆网蛛的壁孔感觉毛对性信息素高度敏感且呈浓度依赖性反应。我们的研究表明存在用于检测发出信号的雌性的雄性特异性感觉毛，而雌性和亚成年雄性则没有壁孔感觉毛。在一项使用来自16个蜘蛛科的19个物种的初步比较形态学分析中，我们发现壁孔感觉毛存在于大多数雄性蜘蛛中，但在基部分支类群或跳蛛科中不存在，这表明壁孔感觉毛在蜘蛛中至少进化了一次且至少消失了一次。这项研究显著扩展了我们对蜘蛛感官生态学的认识，将激发对感觉毛的多样性和功能的研究，以及对节肢动物嗅觉进化的研究。
