The ordinal level phylogeny of the Arachnida and the suprafamilial level phylogeny of the Opiliones were studied on the basis of a combined analysis of 253 morphological characters, the complete sequence of the 18S rRNA gene, and the D3 region of the 28S rRNA gene. Molecular data were collected for 63 terminal taxa. Morphological data were collected for 35 exemplar taxa of Opiliones, but groundplans were applied to some of the remaining chelicerate groups. Six extinct terminals, including Paleozoic scorpions, are scored for morphological characters. The data were analyzed using strict parsimony for the morphological data matrix and via direct optimization for the molecular and combined data matrices. A sensitivity analysis of 15 parameter sets was undertaken, and character congruence was used as the optimality criterion to choose among competing hypotheses. The results obtained are unstable for the high-level chelicerate relationships (except for Tetrapulmonata, Pedipalpi, and Camarostomata), and the sister group of the Opiliones is not clearly established, although the monophyly of Dromopoda is supported under many parameter sets. However, the internal phylogeny of the Opiliones is robust to parameter choice and allows the discarding of previous hypotheses of opilionid phylogeny such as the "Cyphopalpatores" or "Palpatores." The topology obtained is congruent with the previous hypothesis of "Palpatores" paraphyly as follows: (Cyphophthalmi (Eupnoi (Dyspnoi + Laniatores))). Resolution within the Eupnoi, Dyspnoi, and Laniatores (the latter two united as Dyspnolaniatores nov.) is also stable to the superfamily level, permitting a new classification system for the Opiliones.

中文翻译：

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系统发育和Opiliones的系统位置：利用形态学和分子数据对螯合物关系的综合分析。

在综合分析253个形态特征，18S rRNA基因的完整序列和28S rRNA基因的D3区域的基础上，研究了蛛形纲的序生系统发育史和Opiliones的超家族性系统发育史。收集了63个末端类群的分子数据。收集了35个示例性Opiliones类群的形态学数据，但将平面图应用于了其余的螯合物组。对六个灭绝的末端（包括古生蝎）进行了形态学评分。使用严格简约性对形态数据矩阵进行分析，并通过直接优化对分子和组合数据矩阵进行分析。对15个参数集进行了敏感性分析，字符一致性被用作在竞争假设中进行选择的最优标准。对于高水平的螯合剂关系（除四足纲，Pe足纲和Camarostomata以外），所得结果不稳定，尽管许多参数集都支持Dromopoda的单性，但尚没有明确建立Opiliones的姊妹组。然而，阿片酮的内部系统发育对于参数选择是鲁棒的，并且允许丢弃先前的鸦片类系统发育假说，例如“ Cyphopalpatores”或“ Palpatores”。所获得的拓扑结构与以下“ Palpatores”的先前假设一致：（Cyphophthalmi（Eupnoi（Dyspnoi + Laniatores）））。Eupnoi，Dyspnoi，