Wood Louisa E, De Grave Sammy, Daniels Savel R
Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, Matieland, South Africa.
Oxford University Museum of Natural History, Parks Road, Oxford, United Kingdom.
PLoS One. 2017 Mar 10;12(3):e0173356. doi: 10.1371/journal.pone.0173356. eCollection 2017.
We compare the genetic structuring and demographic history of two sympatric caridean shrimp species with distinct life history traits, one amphidromous species Palaemon capensis and one marine/estuarine species Palaemon peringueyi, in the historical biogeographical context of South Africa. A total of 103 specimens of P. capensis collected from 12 localities and 217 specimens of P. peringueyi collected from 24 localities were sequenced for the mitochondrial cytochrome oxidase one (CO1) locus. Results from analyses of molecular variance (AMOVA), pairwise ΦST comparisons and haplotype networks demonstrate weak to moderate genetic differentiation in P. capensis and P. peringueyi respectively. P. peringueyi exhibits partial isolation between populations associated with distinct biogeographic regions, likely driven by the region's oceanography. However, there is minimal evidence for the occurrence of discrete regional evolutionary lineages. This demonstrated lack of genetic differentiation is consistent with a marine, highly dispersive planktonic phase in both the amphidromous P. capensis and the marine/estuarine P. peringueyi. Bayesian skyline plots, mismatch expansions and time since expansion indicate that both species maintained stable populations during the Last Glacial Maximum (LGM), unlike other southern African aquatic species.
在南非的历史生物地理学背景下，我们比较了两种具有不同生活史特征的同域分布的长臂虾科虾类物种的遗传结构和种群历史，一种是洄游性物种南非长臂虾（Palaemon capensis），另一种是海洋/河口物种佩氏长臂虾（Palaemon peringueyi）。对从12个地点采集的103只南非长臂虾标本和从24个地点采集的217只佩氏长臂虾标本的线粒体细胞色素氧化酶亚基I（CO1）基因座进行了测序。分子方差分析（AMOVA）、成对ΦST比较和单倍型网络分析结果表明，南非长臂虾和佩氏长臂虾分别表现出弱到中等程度的遗传分化。佩氏长臂虾在与不同生物地理区域相关的种群之间表现出部分隔离，这可能是由该地区的海洋学特征驱动的。然而，几乎没有证据表明存在离散的区域进化谱系。这种遗传分化的缺乏与洄游性的南非长臂虾和海洋/河口的佩氏长臂虾都具有海洋性、高度分散的浮游阶段是一致的。贝叶斯天际线图、错配扩展分析和扩张时间表明，与其他南部非洲水生物种不同，这两个物种在末次盛冰期（LGM）期间保持了稳定的种群数量。
