Here, we report for the first time the presence of Dictyota cyanoloma in southern California. Dictyota cyanoloma is conspicuous in harbors and bays by its distinctive bright blue‐iridescent margins. This species was originally described from Europe, but subsequent studies have revealed that it represented an introduction from Australia. The current distribution of D. cyanoloma comprises southern Australia and the North East Atlantic, including the Mediterranean Sea and the Macaronesian islands. The presence of D. cyanoloma in southern California is supported by molecular cox1 and psbA gene sequences. A reconstruction of the invasive history based on nine polymorphic microsatellite markers reveals a close affinity of the Californian specimens with European populations. Dictyota cyanoloma in the United States appears to be (so far) restricted to the Californian coast from San Diego Bay in the south to Santa Catalina Island and Long Beach Harbor in the north. A correlative species distribution model suggests gradually declining habitat suitability north of the Southern Californian Bight and high suitability in Baja California, including the Gulf of California. Finally, its widespread abundance in bays and harbors suggests shipping is a likely transport mechanism.

中文翻译：

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Dictyota cyanoloma（Dictyotales，Phaeophyceae），在加利福尼亚新引入的褐藻物种

在这里，我们首次报告了南加州蓝藻（Dictyota cyanoloma）的存在。蓝藻（Dictyota cyanoloma）的港口和海湾因其鲜明的蓝色虹彩边缘而引人注目。该物种最初是从欧洲描述的，但随后的研究表明，它是澳大利亚的一种引种。蓝藻的当前分布包括澳大利亚南部和东北大西洋，包括地中海和马卡罗尼西亚群岛。加利福尼亚州南部的D. cyanoloma的存在得到了分子cox 1和psb的支持一个基因序列。基于九种多态性微卫星标记的入侵史重建表明，加利福尼亚标本与欧洲人群有着密切的亲和力。到目前为止，美国的蓝藻（Dictyota cyanoloma）似乎仅限于从南部的圣地亚哥湾到北部的圣卡塔琳娜岛和长滩港的加利福尼亚海岸。相关的物种分布模型表明，南加利福尼亚湾以北的栖息地适宜性逐渐下降，而下加利福尼亚州（包括加利福尼亚湾）的适宜性则逐渐降低。最后，其在海湾和港口的广泛分布表明航运是一种可能的运输机制。