Data from: Phylogenomic resolution of scorpions reveals multilevel discordance with morphological phylogenetic signal

Scorpions represent an iconic lineage of arthropods, historically renowned for their unique bauplan, ancient fossil record and venom potency. Yet, higher level relationships of scorpions, based exclusively on morphology, remain virtually untested, and no multilocus molecular phylogeny has been deployed heretofore towards assessing the basal tree topology. We applied a phylogenomic assessment to resolve scorpion phylogeny, for the first time, to our knowledge, sampling extensive molecular sequence data from all superfamilies and examining basal relationships with up to 5025 genes. Analyses of supermatrices as well as species tree approaches converged upon a robust basal topology of scorpions that is entirely at odds with traditional systematics and controverts previous understanding of scorpion evolutionary history. All analyses unanimously support a single origin of katoikogenic development, a form of parental investment wherein embryos are nurtured by direct connections to the parent's digestive system. Based on the phylogeny obtained herein, we propose the following systematic emendations: Caraboctonidae is transferred to Chactoidea new superfamilial assignment; superfamily Bothriuroidea revalidated is resurrected and Bothriuridae transferred therein; and Chaerilida and Pseudochactida are synonymized with Buthida new parvordinal synonymies.

蝎子是一类标志性的节肢动物（arthropods）类群，历来以其独特的身体构型（bauplan）、古老的化石记录与强效毒液而广受赞誉。然而，仅基于形态学数据构建的蝎子高级阶元亲缘关系几乎从未得到验证，且迄今为止尚未有基于多基因座分子标记的系统发育研究用于解析其基部拓扑结构。据我们所知，本研究首次应用系统基因组学评估手段解析蝎子系统发育：我们对所有总科类群采集了海量分子序列数据，并基于最多5025个基因位点开展基部亲缘关系分析。超矩阵分析与物种树分析方法均得到了稳健的蝎子基部拓扑结构，该结构与传统分类学认知完全相悖，且颠覆了此前学界对蝎子演化历史的理解。所有分析结果均一致支持具管营养型发育（katoikogenic development）的单一起源——这类亲本抚育策略指胚胎通过直接连接亲代消化系统获得营养供给。基于本研究获得的系统发育树，我们提出以下分类学修订方案：将狭蝎科（Caraboctonidae）归入查科蝎总科（Chactoidea），确立新的总科分类地位；恢复短尾蝎总科（Bothriuroidea）的分类地位，并将短尾蝎科（Bothriuridae）归入该总科；同时将Chaerilida与Pseudochactida异名归入钳蝎目（Buthida），确立新的亚目异名关系。