Nevatte Ryan J, Gillings Michael R, Morejohn Kirby, Ainley Lara, Liggins Libby, Pratchett Morgan S, Hoey Andrew S, Doll Peter C, Pasisi Brendon, Williamson Jane E
School of Natural Sciences Macquarie University Sydney New South Wales Australia.
ARC Centre of Excellence in Synthetic Biology Macquarie University Sydney New South Wales Australia.
Ecol Evol. 2024 Oct 25;14(10):e70474. doi: 10.1002/ece3.70474. eCollection 2024 Oct.
Giant clams ( and ) are large marine bivalves occupying tropical and subtropical reefs in the Indo-Pacific. Giant clam populations have declined in many areas of the Indo-Pacific and continue to be threatened by harvesting and environmental change. The small giant clam () occurs throughout the Indo-Pacific and has been subject to several phylogeographic studies across its range. However, given its broad range, there are several areas where the genetic diversity and connectivity of populations has not been characterised. Here, we analyse the mitochondrial marker cytochrome oxidase 1 (CO1) to examine the genetic diversity and connectivity of in two regions: Australia's Coral Sea Marine Park and the Cook Islands. Samples were collected from 13 reefs within the Coral Sea Marine Park and ten islands within the Cook Islands archipelago. across the sampled region of the Coral Sea did not display any population structure, whereas significant population structure was detected for within the Cook Islands. For the Cook Islands, most pairwise comparisons involving an island in the northern group (Manihiki) were significant, as were comparisons for Palmerston (a more centrally located island) and the southern islands, Rarotonga and Mangaia. Both regions displayed high haplotype diversities (> 0.90), indicating that they are important repositories of genetic diversity. Additional CO1 data from throughout 's distribution showed that the Coral Sea clams belonged to the clade occurring in the South-Western Pacific Ocean, whilst those from the Cook Islands belonged to a unique clade found in the Central Pacific Ocean. This clade extended from Fiji in the west to French Polynesia in the east and the atolls of Palmyra and Tarawa (Kiribati) in the north. Our assessment of genetic diversity and population structure in these regions will assist with management decisions for the species.
巨蛤（ ）是大型海洋双壳贝类，栖息于印度 - 太平洋地区的热带和亚热带珊瑚礁。在印度 - 太平洋的许多区域，巨蛤种群数量已经减少，并且持续受到捕捞和环境变化的威胁。小巨蛤（ ）分布于整个印度 - 太平洋地区，其分布范围内已经开展了多项系统地理学研究。然而，鉴于其分布范围广泛，仍有几个区域的 种群的遗传多样性和连通性尚未得到描述。在此，我们分析线粒体标记细胞色素氧化酶1（CO1），以研究 在两个区域的遗传多样性和连通性：澳大利亚的珊瑚海海洋公园和库克群岛。样本采集自珊瑚海海洋公园内的13个珊瑚礁以及库克群岛群岛内的10个岛屿。珊瑚海采样区域内的 未显示出任何种群结构，而在库克群岛内检测到了显著的种群结构。对于库克群岛，涉及北部组岛屿（马尼希基岛）的大多数成对比较都是显著的，帕默斯顿岛（一个位置更居中的岛屿）与南部岛屿拉罗汤加岛和芒艾亚岛的比较也是如此。两个区域均显示出高单倍型多样性（> 0.90），表明它们是遗传多样性的重要储存库。来自 整个分布范围的额外CO1数据表明，珊瑚海的蛤类属于西南太平洋出现的进化枝，而来自库克群岛的蛤类属于在中太平洋发现的独特进化枝。这个进化枝从西部的斐济延伸到东部的法属波利尼西亚，以及北部的帕尔米拉环礁和塔拉瓦环礁（基里巴斯）。我们对这些区域的遗传多样性和种群结构的评估将有助于该物种的管理决策。
