Determining species boundaries forms an important foundation for biological research. However, the results of molecular species delimitation can vary with the data sets and methods that are used. Here we use a two-step approach to delimit species in the genus Heptathela, a group of primitively segmented trapdoor spiders that are endemic to Japanese islands. Morphological evidence suggests the existence of 19 species in the genus. We tested this initial species hypothesis by using six molecular species-delimitation methods to analyse 180 mitochondrial COI sequences of Heptathela sampled from across the known range of the genus. We then conducted a set of more focused analyses by sampling additional genetic markers from the subset of taxa that were inconsistently delimited by the single-locus analyses of mitochondrial DNA. Multilocus species delimitation was performed using two Bayesian approaches based on the multispecies coalescent. Our approach identified 20 putative species among the 180 sampled individuals of Heptathela. We suggest that our two-step approach provides an efficient strategy for delimiting species while minimizing costs and computational time.

确定物种边界是生物学研究的重要基础。但是，分子种类划界的结果可能会随所使用的数据集和方法而变化。在这里，我们使用两步方法来界定七翅目属中的物种，七翅目属一组原始分割的活板蜘蛛，是日本岛屿特有的。形态学证据表明该属中存在19种。我们通过使用六种分子物种定界方法分析了庚七的180个线粒体COI序列，测试了这一初始物种假说从已知的属范围内取样。然后，我们通过从线粒体DNA的单位点分析不一致地界定的类群子集中采样了其他遗传标记，进行了一组更集中的分析。基于多物种合并，使用两种贝叶斯方法对多基因座物种进行划界。我们的方法在七足莲的180个采样个体中确定了20种推定物种。我们建议我们的两步方法为划定物种提供了一种有效的策略，同时将成本和计算时间降至最低。