Paskerova Gita G, Miroliubova Tatiana S, Valigurová Andrea, Janouškovec Jan, Kováčiková Magdaléna, Diakin Andrei, Sokolova Yuliya Ya, Mikhailov Kirill V, Aleoshin Vladimir V, Simdyanov Timur G
Department of Invertebrate Zoology, Faculty of Biology, St Petersburg State University, St Petersburg, Russia.
Laboratory for Fauna and Systematics of Parasites, Center for Parasitology, Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russian Federation.
PeerJ. 2021 Sep 16;9:e11912. doi: 10.7717/peerj.11912. eCollection 2021.
Gregarines are a major group of apicomplexan parasites of invertebrates. The gregarine classification is largely incomplete because it relies primarily on light microscopy, while electron microscopy and molecular data in the group are fragmentary and often do not overlap. A key characteristic in gregarine taxonomy is the structure and function of their attachment organelles (AOs). AOs have been commonly classified as "mucrons" or "epimerites" based on their association with other cellular traits such as septation. An alternative proposal focused on the AOs structure, functional role, and developmental fate has recently restricted the terms "mucron" to archigregarines and "epimerite" to eugregarines.
Light microscopy and scanning and transmission electron microscopy, molecular phylogenetic analyses of ribosomal RNA genes.
We obtained the first data on fine morphology of aseptate eugregarines and cf. , the type species. We demonstrate that their AOs differ from the mucron in archigregarines and represent an epimerite structurally resembling that in other eugregarines examined using electron microscopy. We then used the concatenated ribosomal operon DNA sequences (SSU, 5.8S, and LSU rDNA) of to explore the phylogeny of eugregarines with a resolution superior to SSU rDNA alone. The obtained phylogenies show that the clade represents an independent, deep-branching family in the Ancoroidea clade within eugregarines. Combined, these results lend strong support to the hypothesis that the epimerite is a synapomorphic innovation of eugregarines. Based on these findings, we resurrect the family Polyrhabdinidae Kamm, 1922 and erect and diagnose the family Trollidiidae fam. n. within the superfamily Ancoroidea Simdyanov et al., 2017. Additionally, we re-describe the characteristics of , emend the diagnoses of the genus , the family Polyrhabdinidae, and the superfamily Ancoroidea.
簇虫是无脊椎动物顶复门寄生虫的主要类群。簇虫的分类在很大程度上并不完整，因为它主要依赖光学显微镜，而该类群的电子显微镜和分子数据零碎且常常不重叠。簇虫分类学的一个关键特征是其附着细胞器（AO）的结构和功能。基于AO与其他细胞特征（如隔膜形成）的关联，AO通常被分类为“尾刺”或“后吸盘”。最近，一项侧重于AO结构、功能作用和发育命运的替代提议将“尾刺”一词仅限于原簇虫，而“后吸盘”仅限于真簇虫。
光学显微镜、扫描和透射电子显微镜、核糖体RNA基因的分子系统发育分析。
我们获得了关于无隔膜真簇虫以及模式种的精细形态的首批数据。我们证明它们的AO与原簇虫的尾刺不同，并且在结构上代表一种后吸盘，类似于使用电子显微镜检查的其他真簇虫中的后吸盘。然后，我们使用的串联核糖体操纵子DNA序列（小亚基、5.8S和大亚基rDNA）来探索真簇虫的系统发育，其分辨率优于单独的小亚基rDNA。获得的系统发育树表明，该进化枝代表真簇虫中锚簇虫超科内一个独立的、分支较深的科。综合来看，这些结果有力地支持了后吸盘是真簇虫的一个共衍征创新的假设。基于这些发现，我们恢复了1922年卡姆的多杆簇虫科，并在2017年辛德亚诺夫等人的锚簇虫超科内建立并诊断了新科特罗利簇虫科。此外，我们重新描述了的特征，修订了属、多杆簇虫科和锚簇虫超科的诊断。
