The dwarf spider Mermessus trilobatus (Araneae: Linyphiidae), native to North America, has expanded its range over large parts of Europe within less than fifty years. It is notable for occurring in a wide range of mostly agricultural habitats, while most other invasive spiders in Europe are associated with human buildings. As in other invasive invertebrates and plants, the tremendous colonisation success of Mermessus trilobatus might be related to anthropogenic habitat disturbance. Here we aim to test if the invasion success of Mermessus trilobatus in Europe is associated with high tolerance towards soil disturbance. We sampled spiders from eight grasslands experimentally disturbed with superficial soil tillage and eight undisturbed grasslands without tillage. Opposite to our expectation, Mermessus trilobatus densities decrease sharply with soil disturbance. This is in contrast to several native species such as Oedothorax apicatus, which becomes more abundant in the fields after superficial soil tillage. Our study suggests that invasion success of Mermessus trilobatus is not connected to a ruderal strategy. The ecological and evolutionary processes behind colonisation success of Mermessus trilobatus need to be further investigated.

矮人蜘蛛Mermessus trilobatus（Araneae：Linyphiidae）原产于北美，在不到五十年的时间里，其范围已扩展到欧洲大部分地区。值得注意的是，它发生在广泛的以农业为主的栖息地中，而欧洲大多数其他侵入性蜘蛛都与人类建筑物有关。与其他侵入性无脊椎动物和植物一样，三叶梅尔摩苏斯（Memessus trilobatus）的巨大定殖成功可能与人为栖息地干扰有关。在这里，我们的目的是测试是否可以成功入侵红mes在欧洲，土壤耐受性高。我们从实验性地受表层土壤耕作干扰的八个草原和未经耕种的八个未受干扰的草原采样了蜘蛛。与我们的预期相反，由于土壤扰动，三叶草的密度急剧下降。这与几种土生土长的物种相反，例如象牙形草（Oedothorax apicatus），它们在表层土壤耕作后在田间变得更加丰富。我们的研究表明，三叶金枪鱼的入侵成功与统治策略无关。Mermessus trilobatus定植成功背后的生态和进化过程需要进一步研究。