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.

蝎子是节肢动物中极具标志性的演化支系，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闻名。然而，此前仅基于形态学数据构建的蝎子高级阶元亲缘关系几乎未得到验证，且迄今尚无多基因座分子系统发育研究用于解析其基部树拓扑结构。据我们所知，本研究首次应用系统基因组学分析方法解析蝎子系统发育关系，采样覆盖所有超科类群的海量分子序列数据，并通过最多5025个基因位点考察其基部亲缘关系。超矩阵分析与物种树（species tree）方法均得到了稳健的蝎子基部拓扑结构，该结果与传统分类学完全相悖，且颠覆了此前学界对蝎子演化历史的认知。所有分析结果均一致支持亲代抚育型发育（katoikogenic development）的单一起源——该类亲代投资策略指胚胎通过与母体消化系统直接连接获取营养的发育方式。基于本研究获得的系统发育树，我们提出如下分类学修订方案：将裸蝎科（Caraboctonidae）归入蛮蝎超科（Chactoidea），确立新的超科级分类归属；重新启用异蝎超科（Bothriuroidea）的分类地位，并将异蝎科（Bothriuridae）归入该超科；同时将查氏蝎下目（Chaerilida）与假蛮蝎下目（Pseudochactida）并入钳蝎下目（Buthida），建立新的亚目级异名。