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.

本研究采用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）序列数据，对塔斯马尼亚扁石蜈蚣（Craterostigmus tasmanianus Pocock, 1902，唇足纲（Chilopoda）：扁石蜈蚣目（Craterostigmomorpha）：扁石蜈蚣科（Craterostigmidae））的种群结构展开探究，并探寻该物种在塔斯马尼亚岛上潜在的基因流障碍——该物种为塔斯马尼亚广泛分布的特有类群。研究首先确认了28S核糖体RNA（28S ribosomal RNA, 28S rRNA）上存在一项分子鉴定特征，可将塔斯马尼亚扁石蜈蚣与其分布于新西兰的姊妹种（sister species）克氏扁石蜈蚣（Craterostigmus crabilli Edgecombe and Giribet 2008）区分开来，且二者在该分子标记中未发现共享多态位点。针对塔斯马尼亚的种群样本，分子方差分析（analysis of molecular variance）结果显示，16S rRNA与COI基因座的种群内变异占比分别仅为6%与13%，而按地理群组划分的种群间变异占比则分别高达56%与48%。曼特尔检验（Mantel test）未发现显著的距离隔离现象。贝叶斯聚类（Bayesian clustering）与基因网络分析（gene network analysis）均显示，塔斯马尼亚扁石蜈蚣的种群聚类模式与此前已知的塔斯马尼亚岛生物地理分区大体吻合，但遗传距离并未随聚类边界呈现简单的变化规律。本研究基于粗尺度地理采样方案，未来应采用更精细的空间采样尺度，以深入探究聚类内部及聚类边界间的遗传结构。