South-western Australia is isolated from other forested regions of Australia by desert and bounded on southern and western sides by the Southern and Indian Oceans, respectively, with Westralunio carteri (Iredale, 1934) as the sole endemic freshwater mussel. Its conservation status is vulnerable. This species has a history of nomenclatural change and its systematic placement and population genetic history are largely unknown. We sampled 46 individuals from 13 sites across W. carteri’s distribution and sequenced two mitochondrial genes (16S rDNA and cytochrome c oxidase subunit I) and one nuclear gene (28S rDNA). The mitochondrial haplotype networks and COI phylogenies revealed three evolutionarily significant units (ESUs): “W. carteri” I including the west coast populations, “W. carteri” II from the south and south-eastern range, and “W. carteri” III only occurring in the south-western tip of Australia. Four species delimitation methods identified two molecular operational taxonomic units supporting two distinct species (“W. carteri” I and “W. carteri” II + III). Phylogeographic patterns revealed herein confirm the historical separation of Western and Southern paleo-basins, also highlighting the isolation of the south-western extremity of the region. This underlines the need for taxonomic revision and will require a re-evaluation of W. carteri’s conservation status.

中文翻译：

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对西澳大利亚淡水贻贝 Westralunio carter 的系统地理学研究揭示了引起新保护问题的进化上重要的单元

澳大利亚西南部被沙漠与澳大利亚的其他森林地区隔开，南部和西部分别以南洋和印度洋为界，Westralunio carteri (Iredale, 1934) 是唯一的地方性淡水贻贝。它的保护状况很脆弱。该物种有命名变化的历史，其系统位置和种群遗传历史在很大程度上是未知的。我们从 W. carteri 分布的 13 个地点对 46 个个体进行了采样，并对两个线粒体基因（16S rDNA 和细胞色素 c 氧化酶亚基 I）和一个核基因（28S rDNA）进行了测序。线粒体单倍型网络和 COI 系统发育揭示了三个进化上重要的单元 (ESU)：“W. 卡特里”我包括西海岸人口，“W. carteri” II 来自南部和东南部，以及“W. carteri” III 仅发生在澳大利亚的西南端。四种物种定界方法确定了支持两种不同物种（“W. carteri” I 和“W. carteri” II + III）的两个分子操作分类单元。这里揭示的系统地理学模式证实了西部和南部古盆地的历史分离，也突出了该地区西南端的孤立。这强调了分类学修订的必要性，并且需要重新评估 W. carteri 的保护状况。这里揭示的系统地理学模式证实了西部和南部古盆地的历史分离，也突出了该地区西南端的孤立。这强调了分类学修订的必要性，并且需要重新评估 W. carteri 的保护状况。这里揭示的系统地理学模式证实了西部和南部古盆地的历史分离，也突出了该地区西南端的孤立。这强调了分类学修订的必要性，并且需要重新评估 W. carteri 的保护状况。