Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China.
Engineering Research Center of Chinese Ministry of Education for Edible and Medicinal Fungi, Jilin Agricultural University, Changchun, 130118, China.
Sci Rep. 2017 Aug 15;7(1):8261. doi: 10.1038/s41598-017-08381-4.
Species delimitation remains a significant challenge when the diagnostic morphological characters are limited. Integrative taxonomy was applied to the genus Protaphorura (Collembola: Onychiuridae), which is one of most difficult soil animals to distinguish taxonomically. Three delimitation approaches (morphology, molecular markers and geography) were applied providing rigorous species validation criteria with an acceptably low error rate. Multiple molecular approaches, including distance- and evolutionary model-based methods, were used to determine species boundaries based on 144 standard barcode sequences. Twenty-two molecular putative species were consistently recovered across molecular and geographical analyses. Geographic criteria were was proved to be an efficient delimitation method for onychiurids. Further morphological examination, based on the combination of the number of pseudocelli, parapseudocelli and ventral mesothoracic chaetae, confirmed 18 taxa of 22 molecular units, with six of them described as new species. These characters were found to be of high taxonomical value. This study highlights the potential benefits of integrative taxonomy, particularly simultaneous use of molecular/geographical tools, as a powerful way of ascertaining the true diversity of the Onychiuridae. Our study also highlights that discovering new morphological characters remains central to achieving a full understanding of collembolan taxonomy.
当诊断形态特征有限时，物种划分仍然是一个重大挑战。综合分类学被应用于Protaphorura 属（弹尾目：Onychiuridae），这是分类上最难区分的土壤动物之一。应用了三种划分方法（形态学、分子标记和地理），提供了严格的物种验证标准，错误率可接受地低。多种分子方法，包括基于距离和进化模型的方法，被用于基于 144 个标准条形码序列确定物种界限。在分子和地理分析中一致发现了 22 个分子假定物种。地理标准被证明是onychiurids 的一种有效的划分方法。进一步的形态学检查，基于假伪感器、副假伪感器和腹面中胸刚毛的数量的组合，证实了 22 个分子单位中的 18 个分类群，其中 6 个被描述为新种。这些特征被发现具有很高的分类价值。本研究强调了综合分类学的潜在益处，特别是同时使用分子/地理工具，是确定onychiuridae 真正多样性的有力方法。我们的研究还表明，发现新的形态特征仍然是全面了解弹尾目分类学的核心。
