Protists of the genus Cytauxzoon infect a wide variety of wild and domestic felids worldwide. While the American Cytauxzoon felis has been well described, data on the European isolates of Cytauxzoon are still scant. The aim of the current study was to determine the genetic diversity of European Cytauxzoon spp. in wild felids across Europe by analyzing one nuclear and two mitochondrial genes, along with representative complete mitochondrial genomes. Overall, 106 biological samples from wild felids (92 from Felis silvestris and 14 from Lynx lynx) from Germany, Romania, Czech Republic, and Luxembourg were collected and screened for the presence of Cytauxzoon spp. using nested PCR protocols, targeting the highly conserved 18S rDNA, mitochondrial cytochrome b (CytB) and cytochrome c oxidase subunit I (COI) genes. Furthermore, 18 previously confirmed wild felid biological samples from Europe, and comparative material from USA positive for C. felis, were included in the study. In 18S rDNA sequences analyses, Cytauxzoon spp. from felids formed two separate clades of New World and Old World isolates, with a low inner diversity of the European clade. In contrast to 18S rDNA, the phylogenetic analyses of CytB and COI genes affirmatively revealed three highly supported clades, resulting in three defined genotypes. Similar intra- and interspecific variability of CytB and COI genes was observed in the case of different Babesia spp. Considering geography, host species and analyses of three genes, we conclude that the three detected genotypes of Cytauxzoon in European wild felids represent three new species, which we herein describe.

Cytauxzoon 属的原生生物感染了世界各地的各种野生和家养猫科动物。虽然美国Cytauxzoon felis已经得到很好的描述，但关于欧洲Cytauxzoon分离株的数据仍然很少。当前研究的目的是确定欧洲Cytauxzoon spp的遗传多样性。通过分析一个核基因和两个线粒体基因，以及具有代表性的完整线粒体基因组，在整个欧洲的野生猫科动物中进行了研究。总的来说，收集了来自德国、罗马尼亚、捷克共和国和卢森堡的106 个野生猫科动物的生物样本（92 个来自Felis silvestris，14 个来自Lynx lynx）并筛选了Cytauxzoon的存在属 使用巢式 PCR 方案，靶向高度保守的 18S rDNA、线粒体细胞色素b (CytB) 和细胞色素c氧化酶亚基 I (COI) 基因。此外，该研究还包括18 个先前确认的来自欧洲的野生猫科动物生物样本和来自美国的对C. felis呈阳性的对比材料。在 18S rDNA 序列分析中，Cytauxzoon属 猫科动物形成了新世界和旧世界分离株的两个独立进化枝，欧洲进化枝的内部多样性较低。与 18S rDNA 相比，CytB 和 COI 基因的系统发育分析肯定地揭示了三个高度支持的进化枝，从而产生了三个明确的基因型。在不同巴贝虫属的情况下观察到 CytB 和 COI 基因的相似种内和种间变异性。考虑到地理、宿主物种和三个基因的分析，我们得出结论，在欧洲野生猫科动物中检测到的三个Cytauxzoon基因型代表了我们在此描述的三个新物种。