Previously considered as a thelytokous parthenogenetic species, the widespread ant cricket Myrmecophilus acervorum actually turns out to have a mixed reproductive system: our recent surveys in the central part of its distribution area has revealed the presence of both sexes. Detailed morphological and morphometric descriptions of the previously unknown males are here provided. New data on species distribution in south-eastern Europe are presented, including the first records of M. balcanicus in Bulgaria and of M. nonveilleri in Bulgaria and Hungary. Phylogenetic and phylogeographic analyses have revealed several haplotypes of M. acervorum in Europe, with six of them forming a parthenogenetic clade in populations distributed west of the Carpathians. We tested our samples for bacterial infection by Wolbachia and, surprisingly, Wolbachia was identified only in populations with both sexes and no amplification was obtained from parthenogenetic populations. Phylogenetic analyses performed with sequences pertaining to five nominal species related to M. acervorum, yielded topological congruent trees with four well-supported groups: one group with M. acervorum samples, the second group with M. nonveilleri samples, the third group with M. fuscus and M. gallicus samples, and the fourth group with samples of M. balcanicus. We performed species delineation tests on our sequences, which delimited between four to seven putative species.

中文翻译：

---

蚂蚁蟋蟀及其秘密：Myrmecophilus acervorum 并不总是孤雌生殖（昆虫纲：直翅目：Myrmecophilidae）

以前被认为是孤雌生殖的物种，分布广泛的蚂蚁蟋蟀 Myrmecophilus acervorum 实际上具有混合生殖系统：我们最近在其分布区域的中部进行的调查显示，存在两性。此处提供了以前未知雄性的详细形态学和形态学描述。介绍了东南欧物种分布的新数据，包括保加利亚的 M. balcanicus 以及保加利亚和匈牙利的 M. nonveilleri 的首次记录。系统发育和系统地理学分析揭示了欧洲 M. acervorum 的几种单倍型，其中六种在喀尔巴阡山脉以西分布的种群中形成孤雌进化枝。我们测试了我们的样本是否被沃尔巴克氏体细菌感染，令人惊讶的是，沃尔巴克氏体仅在两性群体中被发现，并且没有从孤雌生殖群体中获得扩增。使用与 M. acervorum 相关的五个标称物种的序列进行系统发育分析，产生了具有四个良好支持组的拓扑全等树：一组具有 M. acervorum 样品，第二组具有 M. nonveilleri 样品，第三组具有 M. fuscus 和 M. gallicus 样品，第四组是 M. balcanicus 样品。我们对我们的序列进行了物种描述测试，划分了四到七个假定的物种。产生了具有四个良好支持组的拓扑全等树：一组具有 M. acervorum 样本，第二组具有 M. nonveilleri 样本，第三组具有 M. fuscus 和 M. gallicus 样本，第四组具有 M. balcanicus。我们对我们的序列进行了物种描述测试，划分了四到七个假定的物种。产生了具有四个良好支持组的拓扑全等树：一组具有 M. acervorum 样本，第二组具有 M. nonveilleri 样本，第三组具有 M. fuscus 和 M. gallicus 样本，第四组具有 M. balcanicus。我们对我们的序列进行了物种描述测试，划分了四到七个假定的物种。