Paraleucilla magna was the first sponge recognised as alien in the Atlantic. It was first registered in Rio de Janeiro (Brazil) and soon became very abundant in the southeastern and southern coasts of Brazil and also in the Mediterranean. Its origin is still unknown but recurrent introductions seem to have occurred in the Mediterranean. In this study, we used genetic markers (microsatellites) to test if Brazilian and Adriatic populations share a single source or if multiple introductions occurred in both regions. We also compared the genetic composition of populations established almost 30 years ago (Brazil) with a recently founded population (Adriatic—less than 10 years). Populations of P. magna were sampled in four localities across 900 km in the Southwestern Atlantic (Brazilian coast) and in one locality in the Adriatic (Croatian coast). Our results suggest the presence of five genetically distinct populations possibly originated by multiple human-mediated introductions from different sources and show that the putative most recently established population is genetically more diverse.

中文翻译：

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种群分化支持多种人类介导的跨大西洋异国海绵 Paraleucilla magna（Porifera，Calcarea）的引入

Paraleucilla magna 是大西洋中第一个被确认为外星人的海绵。它首先在里约热内卢（巴西）注册，很快在巴西东南部和南部海岸以及地中海地区变得非常丰富。它的起源仍然未知，但似乎在地中海发生了反复引入。在这项研究中，我们使用遗传标记（微卫星）来测试巴西和亚得里亚海的种群是否共享单一来源，或者两个地区是否发生了多次引入。我们还比较了近 30 年前建立的种群（巴西）与最近建立的种群（亚得里亚海——不到 10 年）的遗传组成。P. magna 种群在西南大西洋（巴西海岸）900 公里的四个地点和亚得里亚海（克罗地亚海岸）的一个地点采样。