1. The five global Mediterranean‐climate regions are experiencing alarming rates of freshwater biodiversity loss. Although freshwater mussels are recognized as important functional components in aquatic ecosystems, and are among the most threatened faunal groups globally, there has been no synthesis of the plight of this group within these regions.
2. Data from the International Union for Conservation of Nature (IUCN) Red List were reviewed to compare the conservation status, threats, and conservation actions needed for freshwater mussel species occurring in Mediterranean‐climate regions (med‐mussels) with those of other freshwater mussel species globally. The first comprehensive catalogue of med‐mussel species was compiled using existing taxonomic literature.
3. There are 41 med‐mussel species, 30 of which occur in the Mediterranean basin. Many regions have just a single species, and regions where multiple species occur generally only have between one and four species per river basin. Med‐mussel species are almost twice as likely to be ‘Imperilled’, are affected by 2.4 times more threats, and require 3.5 times more conservation actions than non‐med mussels. In many cases, the exact threats have not been identified.
4. In combination with low species richness, this level of imperilment means that Mediterranean‐climate regions are at risk of losing the benefits that mussels provide to broader ecosystem functioning. The conservation of med‐mussels can be improved by increasing our knowledge of species distributions, including the identification of cryptic species and significant management units, through population genetic work. In addition, recognizing the potential of ‘novel’ habitats and refuge areas could augment the management of this important functional group.

中文翻译：

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地中海气候区的淡水贻贝：物种丰富度，保护状况，威胁和需要采取的保护行动

1. 地中海五个全球气候区域的淡水生物多样性丧失速度惊人。尽管淡水贻贝被公认为水生生态系统中的重要功能成分，并且是全球受威胁最大的动物群之一，但在这些区域内，该群体的困境尚未得到综合。
2. 审查了来自国际自然保护联盟（IUCN）红色名录的数据，以比较发生在地中海气候区（淡水贻贝）的淡水贻贝物种与其他淡水贻贝物种的保护现状，威胁和保护行动全球范围。贻贝物种的第一个综合目录是使用现有分类学文献编制的。
3. 贻贝有41种，其中30种发生在地中海盆地。许多地区只有一个物种，而每个流域通常会出现多种物种的地区通常只有一到四种。贻贝的种类被“濒危”的几率几乎是其两倍，受到的威胁要多于非贻贝的2.4倍，并且需要采取的保护行动是非贻贝的3.5倍。在许多情况下，尚未确定确切的威胁。
4. 再加上物种丰富度低，这种低水平的危害意味着地中海-气候区可能失去贻贝为更广泛的生态系统功能所提供的利益。贻贝的保护可以通过增加我们对物种分布的了解来改善，包括通过种群遗传工作来识别隐性物种和重要的管理单位。此外，认识到“新颖”的栖息地和避难所的潜力可以加强对这一重要职能部门的管理。