Invasive alien species are driving global biodiversity loss, compromising ecosystem function and service provision, and human, animal and plant health. Habitat characteristics and geographical origin may predict invasion success, and in aquatic environments could be mediated principally by salinity tolerance. Crustacean invaders are causing global problems and we urgently require better predictive power of their invasiveness. Here, we compiled global aquatic gammarid (Crustacea: Amphipoda: Gammaroidea) diversity and examined their salinity tolerances and regions of origin to test whether these factors predict invasion success. Across 918 aquatic species within this superfamily, relatively few gammarids (n = 27, 3%) were reported as aliens, despite extensive invasion opportunities and high numbers of published studies on amphipod invasions. However, reported alien species were disproportionately salt-tolerant (i.e. 32% of brackish-water species), with significantly lower proportions of aliens originating from freshwater and marine environments (both 1%). Alien gammarids also significantly disproportionally originated from the Ponto-Caspian (20% of these taxa) when compared with all ‘other' grouped regions (1%), and principally invaded Eurasian waters, with translocations of salt-tolerant taxa to freshwaters being pervasive. This suggests habitat characteristics, alongside regional contexts, help predict invasibility. In particular, broad environmental tolerances to harsh environments and associated evolutionary history probably promote success of aliens globally.

外来入侵物种正在推动全球生物多样性丧失，损害生态系统功能和服务提供以及人类，动植物的健康。栖息地的特征和地理起源可以预测入侵的成功，而在水生环境中，主要可以通过耐盐性来介导。甲壳类入侵者正在引起全球性问题，我们迫切需要更好地预测其入侵性。在这里，我们汇总了全球水生γ-酰胺类（甲壳纲：两栖类：Gammaroidea）多样性，并检查了它们的盐度耐受性和起源区域，以检验这些因素是否预示了入侵的成功。在该超科内的918个水生物种中，相对较少的gammarids（n尽管有广泛的入侵机会和大量关于两栖类动物入侵的已发表研究，但仍有27％（3％）被报告为外星人。然而，据报道外来物种的耐盐性不成比例（即微咸水物种的32％），而来自淡水和海洋环境的外来物种比例则明显较低（均为1％）。与所有“其他”分组区域（1％）相比，外来γ-内酰胺类也明显不成比例地起源于蓬图里海（占这些分类单元的20％），并且主要是入侵的欧亚水域，耐盐类群易位到淡水。这表明栖息地特征以及区域背景有助于预测入侵性。尤其是，