Data from: Phylogeny and morphologic evolution of the Ordovician Camerata (Class Crinoidea, Phylum Echinodermata)

The subclass Camerata (Crinoidea, Echinodermata) is a major group of Paleozoic crinoids that represents an early divergence in the evolutionary history and morphologic diversification of class Crinoidea, yet phylogenetic relationships among early camerates remain unresolved. This study conducted a series of quantitative phylogenetic analyses using parsimony methods to infer relationships of all well-preserved Ordovician camerate genera (52 taxa), establish the branching sequence of early camerates, and test the monophyly of traditionally recognized higher taxa, including orders Monobathrida and Diplobathrida. The first phylogenetic analysis identified a suitable outroup for rooting the Ordovician camerate tree and assessed affinities of the atypical dicyclic family Reteocrinidae. The second analysis inferred the phylogeny of all well-preserved Ordovician camerate genera. Inferred phylogenies confirm: (1) the Tremadocian genera Cnemecrinus and Eknomocrinus are sister to the Camerata; (2) as historically defined, orders Monobathrida and Diplobathrida do not represent monophyletic groups; (3) with minimal revision, Monobathrida and Diplobathrida can be re-diagnosed to represent monophyletic clades; (4) family Reteocrinidae is more closely related to camerates than to other crinoid groups currently recognized at the subclass level; and (5) several genera in subclass Camerata represent stem taxa that cannot be classified as either true monobathrids or true diplobathrids. The clade containing Monobathrida and Diplobathrida, as recognized herein, is termed Eucamerata to distinguish its constituent taxa from more basally positioned taxa, termed stem eucamerates. The results of this study provide a phylogenetic framework for revising camerate classification, elucidating patterns of morphologic evolution, and informing outgroup selection for future phylogenetic analyses of post-Ordovician camerates.亚纲卡梅拉海百合亚纲（Camerata）隶属于棘皮动物门（Echinodermata）海百合纲（Crinoidea），是古生代海百合类群的主要类群，代表了海百合纲演化历史与形态辐射分化中的早期分支类群，但早期卡梅拉海百合类群间的系统发育关系至今尚未厘清。本研究采用简约法开展了一系列定量系统发育分析，以解析所有保存完好的奥陶纪卡梅拉海百合属类群（共52个分类单元）的亲缘关系，明确早期卡梅拉海百合类群的分支序列，并检验传统分类中高阶类群的单系性，包括单海百合目（Monobathrida）与双海百合目（Diplobathrida）。首次系统发育分析确定了用于定根奥陶纪卡梅拉海百合类群系统树的合适外类群，并评估了非典型双环型类群网海百合科（Reteocrinidae）的亲缘关系。第二项分析则解析了所有保存完好的奥陶纪卡梅拉海百合属类群的系统发育关系。解析得到的系统发育结果证实：（1）特马豆克期的Cnemecrinus与Eknomocrinus两属为卡梅拉海百合亚纲的姊妹群；（2）按传统定义的单海百合目与双海百合目并非单系类群；（3）仅需进行少量修订，即可将单海百合目与双海百合目重新诊断为单系演化支；（4）网海百合科与卡梅拉海百合类群的亲缘关系，较其与当前公认的其他亚纲级海百合类群更为紧密；（5）卡梅拉海百合亚纲中有多个属属于基干分类单元，无法被归入真正的单海百合类群或双海百合类群。本研究将包含单海百合目与双海百合目的演化支命名为真卡梅拉海百合亚纲（Eucamerata），以此将该演化支的类群与处于更基干位置的基干真卡梅拉海百合类群相区分。本研究结果为修订卡梅拉海百合类群的分类体系、阐明形态演化模式，以及为后续奥陶纪之后卡梅拉海百合类群的系统发育分析提供外类群选择参考，构建了系统发育框架。