Abstract. Pseudospirobolellidae is a poorly known family of spirobolidan millipedes with only two genera and five described species. Yet, the descriptive taxonomy and molecular systematics of this group have been largely neglected. Therefore, the present work presents an integrative taxonomic study of new pseudospirobolellid taxa in Thailand. To this end, two mitochondrial gene fragments (COI and 16S rRNA) combined with morphological characters were used to define the genus Coxobolellus, gen. nov. with 10 new species, viz. C. albiceps, sp. nov., C. compactogonus, sp. nov., C. fuscus, sp. nov., C. nodosus, sp. nov., C. serratus, sp. nov., C. simplex, sp. nov., C. tenebris, sp. nov., C. tigris, sp. nov., C. transversalis, sp. nov. and C. valvatus, sp. nov. The interspecific COI sequence divergences among the new species ranged from 6 to 15%. The intergeneric COI sequence divergence between species of Coxobolellus, gen. nov., Benoitolus birgitae and Pseudospirobolellus sp. ranged from 20 to 23%. Three major morphological differences separate Coxobolellus, gen. nov. from Benoitolus and Pseudospirobolellus, namely (1) the protruding process on the 3rd (and 4th) coxae on male legs, (2) the posterior gonopod telopodite divided into two parts, and (3) a conspicuous opening pore at the mesal margin at the end of the coxal part of the posterior gonopod. Thus, the new genus is well supported by both mtDNA and morphological evidence, while the delimitation of the 10 new species is supported by the congruence between mtDNA and morphological data. Yet, with respect to the relationships of Benoitolus birgitae, morphological data suggest a similarity with Coxobolellus, gen. nov. and Pseudospirobolellus, whereas mtDNA data place this species in the Pachybolidae. Further phylogenetic analyses are needed to explore this apparent incongruence and test the monophyly of Pseudospirobolellidae.

中文翻译：

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新千足虫属 Coxobolellus 的综合分类学，gen。十一月 （双足纲：Spirobolida：Pseudospirobolellidae），描述了十个新物种

摘要。Pseudospirobolellidae 是一个鲜为人知的 spirobolidan 千足虫家族，只有两个属和五个描述的物种。然而，该群体的描述性分类学和分子系统学在很大程度上被忽视了。因此，目前的工作对泰国新的拟螺菌类群进行了综合分类学研究。为此，结合形态特征的两个线粒体基因片段（COI 和 16S rRNA）被用来定义 Coxobolellus 属，gen。十一月 有 10 个新物种，即。C. 白头肌，sp。nov., C. compactogonus, sp. nov., C. fuscus, sp. nov., C. nodosus, sp. nov., C. serratus, sp. nov., C. simplex, sp. nov., C. tenebris, sp. nov., C. tigris, sp. nov., C. transversalis, sp. 十一月 和 C. valvatus, sp。十一月 新物种之间的种间 COI 序列差异在 6% 到 15% 之间。Coxobolellus 属之间的 COI 序列差异，gen。11 月，Benoitolus birgitae 和 Pseudospirobolellus sp。20% 到 23% 不等。三个主要的形态差异将 Coxobolellus 分开。十一月 来自Benoitolus和Pseudospirobollus，即（1）雄性腿第3（和第4）节的突出突起，（2）后生殖器端足分为两部分，（3）在中缘有一个明显的开孔后生殖器的髋部末端。因此，mtDNA 和形态学证据都很好地支持了新属，而 mtDNA 和形态学数据之间的一致性支持了 10 个新物种的定界。然而，关于 Benoitolus birgitae 的关系，形态学数据表明与 Coxobolellus, gen 相似。十一月 和 Pseudospirobolellus，而 mtDNA 数据将该物种归入 Pachybolidae。需要进一步的系统发育分析来探索这种明显的不一致并测试 Pseudospirobollidae 的单系。