1. The freshwater mussel (Unionida) fauna of the Yangtze River is among the most diverse on Earth. In recent decades, human activities have caused habitat degradation in the river, and previous studies estimated that up to 80% of the mussel species in the Yangtze River are Threatened or Near Threatened with extinction. However, a comprehensive and systematic evaluation of the conservation status of this fauna has yet to be completed.
2. This study evaluated the conservation status of the 69 recognized freshwater mussel species in the middle and lower reaches of the Yangtze River, using the criteria published by the International Union for Conservation of Nature (IUCN). A new method for prioritizing species for conservation was then developed and applied termed Quantitative Assessment of Species for Conservation Prioritization (QASCP), which prioritizes species according to quantifiable data on their distribution and population status, life history, and recovery importance and potential.
3. IUCN assessments showed that 35 (51%) species in the study region are Threatened or Near Threatened (11 Endangered, 20 Vulnerable, 4 Near Threatened). In addition, 16 species (23%) could not be assessed owing to data deficiency. Key threats to the freshwater mussel biodiversity of the Yangtze River include pollution, habitat loss and fragmentation, loss of access to host fish, and overharvesting of mussels and their host fish. The genera Aculamprotula, Gibbosula, Lamprotula, Pseudodon, Ptychorhynchus, and Solenaia were identified as particularly threatened.
4. Data availability allowed QASCP assessment of 44 species. Only Solenaia carinata, regionally Endangered under IUCN criteria, achieved the highest QASCP rank, i.e. First Priority. The five species assessed as Second Priority were considered either regionally Endangered (one), Vulnerable (three), or Data Deficient (one) under IUCN criteria. The 23 Third Priority species were assessed as regionally Endangered (two), Vulnerable (15), Near Threatened (two), or Least Concern (four).

中文翻译：

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长江中下游淡水贻贝（双壳纲：Unionida）的保护现状评估和确定保护重点的新方法

1. 长江的淡水贻贝（Unionida）动物群是地球上种类最丰富的动物之一。近几十年来，人类活动已导致河流中的栖息地退化，并且先前的研究估计，长江中高达80％的贻贝物种受到灭绝的威胁或近乎威胁。但是，尚未对该动物的保护状况进行全面和系统的评估。
2. 这项研究使用国际自然保护联盟（IUCN）发布的标准，评估了长江中下游69种公认的淡水贻贝物种的保护状况。然后，开发了一种新的优先保护物种的方法，并将其称为“保护物种优先评估”（QASCP），该方法根据可量化的物种，分布，种群状况，生活史以及恢复重要性和潜力的数据对物种进行优先排序。
3. IUCN评估显示，研究区域中有35（51％）种受到威胁或濒临灭绝（11种濒危，20种脆弱，4种濒临灭绝）。此外，由于数据不足，无法评估16种（23％）。长江淡水贻贝生物多样性面临的主要威胁包括污染，栖息地丧失和破碎化，失去寄主鱼类的供应以及贻贝及其寄主鱼类的过度捕捞。该属Aculamprotula，Gibbosula，丽蚌，Pseudodon，Ptychorhynchus和橄榄蛏蚌被认定为特别的威胁。
4. 数据可用性允许QASCP评估44种。仅在IUCN标准下区域濒危的加勒比海茄属（Solenaia carinata）获得了最高的QASCP排名，即第一优先。根据自然保护联盟的标准，​​被评定为第二优先级的五个物种被认为是区域濒危物种（一个），脆弱物种（三个）或数据不足物种（一个）。23种第三优先物种被评估为区域性濒危物种（两个），易危物种（15个），濒危物种（两个）或最不关注物种（四个）。