School of Biosciences and Veterinary Medicine, Laboratory of Animal and Molecular Ecology, University of Camerino, Camerino, MC, Italy.
Zoological Survey of India, Prani Vigyan Bhawan, New Alipore, Kolkata, India.
PLoS One. 2018 Nov 20;13(11):e0207688. doi: 10.1371/journal.pone.0207688. eCollection 2018.
Present study, investigates a poorly known species of the genus Sterkiella, i.e., S. tricirrata, based on two populations isolated from soil samples collected from the Colfiorito Regional Park, Umbria Region, Italy and from the Silent Valley National Park, India. Both populations showed a highly similar morphology, however different ontogenetic pattern in between. The study confirms the validity of the species S. tricirrata which was considered to be a species within the Sterkiella histriomuscorum complex. The main ontogenetic difference between S. tricirrata and other species of the genus Sterkiella is the different mode of formation of anlagen V and VI of the proter in the former. In the phylogenetic analyses, Sterkiella tricirrata clusters with Sterkiella sinica within the stylonychine oxytrichids, in a clade away from the type species (Sterkiella cavicola) of the genus Sterkiella. The study highlights the importance of ontogenetic as well as molecular data in shedding light on the polyphyletic behavior of the genus Sterkiella. A detailed description of S. tricirrata based on morphology, ontogenesis and molecular phylogenetic methods is presented. Further, the improved diagnosis has been provided for the genus Sterkiella and the poorly known species S. tricirrata.
本研究基于从意大利翁布里亚大区科尔菲托地区公园和印度寂静谷国家公园采集的土壤样本中分离出的两个种群，对鲜为人知的 Sterkiella 属物种，即 S. tricirrata 进行了研究。两个种群表现出高度相似的形态，但在个体发生模式上存在差异。本研究证实了 S. tricirrata 物种的有效性，该物种曾被认为是 Sterkiella histriomuscorum 复合体中的一个物种。S. tricirrata 与 Sterkiella 属其他物种的主要个体发生差异在于前者原虫 V 和 VI 体节原基的形成方式不同。在系统发育分析中，Sterkiella tricirrata 与 Stylonychia oxytrichids 中的 Sterkiella sinica 聚类，与属内的 Sterkiella cavicola （ Sterkiella 属的模式种）形成一个分支。本研究强调了个体发生和分子数据在阐明 Sterkiella 属的多系行为方面的重要性。本文基于形态学、个体发生和分子系统发育方法对 S. tricirrata 进行了详细描述。此外，还为 Sterkiella 属和鲜为人知的 S. tricirrata 提供了改进的诊断。
