Data from: Large‐scale species delimitation method for hyperdiverse groups

Accelerating the description of biodiversity is a major challenge as extinction rates increase. Integrative taxonomy combining molecular, morphological, ecological and geographical data is seen as the best route to reliably identify species. Classic molluscan taxonomic methodology proposes primary species hypotheses (PSHs) based on shell morphology. However, in hyperdiverse groups, such as the molluscan family Turridae, where most of the species remain unknown and for which homoplasy and plasticity of morphological characters is common, shell‐based PSHs can be arduous. A four‐pronged approach was employed to generate robust species hypotheses of a 1000 specimen South‐West Pacific Turridae data set in which: (i) analysis of COI DNA Barcode gene is coupled with (ii) species delimitation tools GMYC (General Mixed Yule Coalescence Method) and ABGD (Automatic Barcode Gap Discovery) to propose PSHs that are then (iii) visualized using Klee diagrams and (iv) evaluated with additional evidence, such as nuclear gene rRNA 28S, morphological characters, geographical and bathymetrical distribution to determine conclusive secondary species hypotheses (SSHs). The integrative taxonomy approach applied identified 87 Turridae species, more than doubling the amount previously known in the Gemmula genus. In contrast to a predominantly shell‐based morphological approach, which over the last 30 years proposed only 13 new species names for the Turridae genus Gemmula, the integrative approach described here identified 27 novel species hypotheses not linked to available species names in the literature. The formalized strategy applied here outlines an effective and reproducible protocol for large‐scale species delimitation of hyperdiverse groups.

随着物种灭绝速率不断攀升，加速生物多样性描述已成为一项重大科研挑战。整合分类学将分子、形态、生态与地理数据相结合，被视为可靠鉴定物种的最优路径。经典软体动物分类学方法依托贝壳形态特征提出物种一级假说（primary species hypotheses, PSHs）。但在物种高度多样的类群中——例如多数物种仍未被发现、且形态特征普遍存在趋同演化与可塑性的卷管螺科（Turridae）——基于贝壳的物种一级假说往往难以成立。
本研究针对西南太平洋1000份卷管螺科标本数据集，采用四项并行的研究策略以构建稳健可靠的物种假说：(i) 分析COI DNA条形码基因，并结合(ii) 物种界定工具GMYC（General Mixed Yule Coalescence Method，广义混合尤尔合并法）与ABGD（Automatic Barcode Gap Discovery，自动条形码间隙发现法）提出物种一级假说；随后(iii) 利用Klee图对上述假说进行可视化呈现，并(iv) 辅以核基因rRNA 28S、形态特征、地理与水深分布等额外证据开展评估，最终确定严谨的物种二级假说（secondary species hypotheses, SSHs）。
本研究所应用的整合分类学方法共鉴定出87种卷管螺科物种，数量较此前已知的纺轴螺属（Gemmula）物种数翻了一番还多。相较于近三十余年来主流的贝壳形态分类方法仅为纺轴螺属提出13个新物种学名，本研究的整合分类学策略共识别出27个未对应文献中已有物种学名的全新物种假说。本研究提出的标准化研究框架，为高度多样类群的大规模物种界定提供了一套高效且可复现的操作范式。