Chaves-Fonnegra Andia, Feldheim Kevin A, Secord Jesse, Lopez Jose V
Nova Southeastern University, Oceanographic Center, 8000 North Ocean Drive, Dania Beach, FL, 33004, USA.
Mol Ecol. 2015 Apr;24(7):1447-66. doi: 10.1111/mec.13134. Epub 2015 Mar 20.
Some excavating sponges of the genus Cliona compete with live reef corals, often killing and bioeroding entire colonies. Important aspects affecting distribution of these species, such as dispersal capability and population structure, remain largely unknown. Thus, the aim of this study was to determine levels of genetic connectivity and dispersal of Cliona delitrix across the Greater Caribbean (Caribbean Sea, Bahamas and Florida), to understand current patterns and possible future trends in their distribution and effects on coral reefs. Using ten species-specific microsatellite markers, we found high levels of genetic differentiation between six genetically distinct populations: one in the Atlantic (Florida-Bahamas), one specific to Florida and four in the South Caribbean Sea. In Florida, two independent breeding populations are likely separated by depth. Gene flow and ecological dispersal occur among other populations in the Florida reef tract, and between some Florida locations and the Bahamas. Similarly, gene flow occurs between populations in the South Caribbean Sea, but appears restricted between the Caribbean Sea and the Atlantic (Florida-Bahamas). Dispersal of C. delitrix was farther than expected for a marine sponge and favoured in areas where currents are strong enough to transport sponge eggs or larvae over longer distances. Our results support the influence of ocean current patterns on genetic connectivity, and constitute a baseline to monitor future C. delitrix trends under climate change.
一些穿贝海绵属的挖掘海绵会与活珊瑚礁竞争，常常杀死并生物侵蚀整个珊瑚群落。影响这些物种分布的重要方面，如扩散能力和种群结构，在很大程度上仍然未知。因此，本研究的目的是确定加勒比礁穿贝海绵在大加勒比地区（加勒比海、巴哈马群岛和佛罗里达州）的遗传连通性和扩散水平，以了解其当前的分布模式以及未来可能的趋势及其对珊瑚礁的影响。使用十个物种特异性微卫星标记，我们发现六个遗传上不同的种群之间存在高度的遗传分化：一个在大西洋（佛罗里达州 - 巴哈马群岛），一个特定于佛罗里达州，四个在南加勒比海。在佛罗里达州，两个独立的繁殖种群可能因深度而分隔。基因流动和生态扩散发生在佛罗里达礁区的其他种群之间，以及佛罗里达州的一些地点和巴哈马群岛之间。同样，基因流动发生在南加勒比海的种群之间，但似乎在加勒比海和大西洋（佛罗里达州 - 巴哈马群岛）之间受到限制。加勒比礁穿贝海绵的扩散距离比海洋海绵预期的更远，并且在水流足够强大以将海绵卵或幼虫输送到更远距离的区域更有利。我们的结果支持洋流模式对遗传连通性的影响，并构成了在气候变化下监测未来加勒比礁穿贝海绵趋势的基线。
