Data from: The Nearctic Nedubini: the most basal lineage of katydids is resolved among the paraphyletic “Tettigoniinae” (Orthoptera: Tettigoniidae)

This study investigated the systematics of the Nearctic shield-back katydids (“Tettigoniinae”), a paraphyletic group thought to include genera from a distinctive Gondwanan tribe, the Nedubini, among an otherwise Holarctic fauna. From exemplars of five genera of Nedubini and the majority of other genera of Nearctic “Tettigoniinae,” five gene regions were sequenced, aligned with publicly available sequence data that represent diverse subfamilies of Tettigoniidae, and subjected to phylogenetic analysis under Bayesian and likelihood criteria. Our results render the worldwide Nedubini polyphyletic, strongly support the Nearctic Nedubini as a basal clade that is sister to the remaining Tettigoniidae, and group the remaining Nearctic shield-back katydid genera into a Holarctic clade. Having shared a common ancestor with the remaining katydids 175 ± 24 million years ago, the Nearctic Nedubini joins a considerable assemblage of relict groups that are found in California and the Pacific Northwest of North America. The symmetrical development and ambidextrous overlap of the tegmina of male Nearctic nedubines is re-evaluated as a plesiomorphic character.本研究针对新北区背盾螽斯类群（隶属于螽斯亚科Tettigoniinae）的系统分类学展开探讨。该类群为并系群，被认为包含源自独特冈瓦纳内杜螽族（Nedubini）的多个属，而其余类群则隶属于全北区动物区系。研究选取了内杜螽族5个属以及新北区绝大多数其他螽斯亚科属的标本，对5个基因区域进行测序，并与公开可用的、涵盖螽斯科（Tettigoniidae）多个亚科的序列数据进行比对，随后基于贝叶斯法与似然法标准开展系统发育分析。本研究结果表明，全球范围内的内杜螽族为多系群；本研究强烈支持新北区内杜螽族作为基部分支，与其余螽斯科类群构成姊妹群；同时将剩余新北区背盾螽斯属归入一个全北区分支。新北区内杜螽族与其余螽斯类群的共同祖先可追溯至1.75±0.24亿年前，该类群与分布于北美加利福尼亚州及太平洋西北地区的大量孑遗类群同属一类。雄性新北区内杜螽的覆翅对称发育与左右手式叠合特征，被重新评估为一项祖征。