Zlatogursky Vasily V, Drachko Daria, Klimov Vladimir I, Shishkin Yegor
Department of Invertebrate Zoology, Faculty of Biology, St. Petersburg State University, Universitetskaja nab. 7/9, 199034, St. Petersburg, Russia; Department of Organismal Biology, Systematic Biology Program, Uppsala University, Kåbovägen 4A, SE-752 36, Uppsala, Sweden.
Department of Invertebrate Zoology, Faculty of Biology, St. Petersburg State University, Universitetskaja nab. 7/9, 199034, St. Petersburg, Russia.
Eur J Protistol. 2018 Jun;64:82-90. doi: 10.1016/j.ejop.2018.03.006. Epub 2018 Apr 5.
Centrohelid heliozoan Raphidocystis glabra was reisolated for the first time after initial description and put into a clonal culture. Its correct identification was confirmed by scanning and transmission electron microscopy of scales. The first light microscopy data from the living cells were obtained. Phylogenetic analysis of its position using 18S rDNA sequences was also performed. This species branches inside of the Polyplacocystis clade, being closely related to the strain HLO4. The latter was isolated from the same sample with R. glabra and has spicules, not siliceous scales, unlike all the other members of this clade. Using another strain isolated from this sample the co-specificity of HLO4 and R. glabra was demonstrated, and the presence of spicule-bearing stages in the life cycle of Raphidocystis was shown. Polyplacocystis revealed to be paraphyletic with Raphidocystis embedded in it. Moreover, representatives of both genera share the similar monolayered plate scales with hollow inflected margin. Thus, a family-level name Raphidocystidae for the whole clade was proposed and all the Polyplacocystis species were transferred to Raphidocystis which name has a priority. The evolution of centrohelid coverings in the light of new findings was discussed, as well as the possible wide distribution of dimorphism in centrohelid life cycles.
中心太阳虫类的光裸针胞太阳虫在最初描述后首次被重新分离并进行克隆培养。通过鳞片的扫描电子显微镜和透射电子显微镜观察，确认了其正确的鉴定。获得了来自活细胞的首批光学显微镜数据。还利用18S rDNA序列对其位置进行了系统发育分析。该物种在多囊虫类分支内部，与菌株HLO4密切相关。后者与光裸针胞太阳虫从同一样本中分离得到，与该类群的所有其他成员不同，它具有骨针而非硅质鳞片。利用从该样本中分离出的另一个菌株，证明了HLO4与光裸针胞太阳虫的同特异性，并显示了针胞太阳虫生命周期中存在带骨针阶段。结果表明多囊虫类是并系的，其中嵌入了针胞太阳虫。此外，两个属的代表都具有边缘中空且弯曲的单层板状鳞片。因此，为整个类群提出了科级名称针胞太阳虫科，并将所有多囊虫类物种转移到具有优先权的针胞太阳虫属。根据新发现讨论了中心太阳虫类覆盖物的演化，以及中心太阳虫类生命周期中可能广泛存在的二态性。
