Data from: Biogeography in a continental island: population structure of the relict endemic centipede Craterostigmus tasmanianus (Chilopoda, Craterostigmomorpha) in Tasmania using 16S rRNA and COI

We used 16S ribosomal RNA (rRNA) and cytochrome c oxidase subunit I (COI) sequence data to investigate the population structure in the centipede Craterostigmus tasmanianus Pocock, 1902 (Chilopoda: Craterostigmomorpha: Craterostigmidae) and to look for possible barriers to gene flow on the island of Tasmania, where C. tasmanianus is a widespread endemic. We first confirmed a molecular diagnostic character in 28S rRNA separating Tasmanian Craterostigmus from its sister species Craterostigmus crabilli (Edgecombe and Giribet 2008) in New Zealand and found no shared polymorphism in this marker for the 2 species. In Tasmania, analysis of molecular variance analysis showed little variation at the 16S rRNA and COI loci within populations (6% and 13%, respectively), but substantial variation (56% and 48%, respectively) among populations divided geographically into groups. We found no clear evidence of isolation by distance using a Mantel test. Bayesian clustering and gene network analysis both group the C. tasmanianus populations in patterns which are broadly concordant with previously known biogeographical divisions within Tasmania, but we did not find that genetic distance varied in a simple way across cluster boundaries. The coarse-scale geographical sampling on which this study was based should be followed in the future by sampling at a finer spatial scale and to investigate genetic structure within clusters and across cluster boundaries.本研究利用16S核糖体RNA（16S ribosomal RNA，rRNA）与细胞色素c氧化酶亚基I（cytochrome c oxidase subunit I，COI）的序列数据，探究蜈蚣类群塔斯马尼亚洞蜈蚣（Craterostigmus tasmanianus Pocock, 1902，分类地位：唇足纲（Chilopoda）、洞蜈蚣目（Craterostigmomorpha）、洞蜈蚣科（Craterostigmidae））的种群结构，该物种为塔斯马尼亚岛上广布的特有种，本研究同时探寻该岛上阻碍其种群间基因交流的潜在屏障。本研究首先在28S核糖体RNA（28S rRNA）中确认了可区分塔斯马尼亚洞蜈蚣与其新西兰姊妹种C. crabilli（Edgecombe与Giribet, 2008）的分子鉴定特征，且两物种在该分子标记中未发现共享的多态位点。针对塔斯马尼亚岛种群的分子变异分析结果显示：16S rRNA与COI基因座的种群内变异占比仅分别为6%与13%，而按地理分组的种群间变异占比则高达56%与48%。通过曼特尔检验（Mantel test）未发现显著的距离隔离效应。贝叶斯聚类（Bayesian clustering）与基因网络分析均将塔斯马尼亚洞蜈蚣的种群划分为与该岛已知生物地理分区大体一致的类群，但未发现遗传距离在聚类边界处呈现简单的变化规律。本研究基于的粗尺度地理采样方案，未来应辅以更精细的空间尺度采样，以探究各聚类内部及聚类边界间的种群遗传结构。