Laboratory of Protozoological Biodiversity and Evolution in Wetland, College of Life Sciences, Shaanxi Normal University, Xi'an 710119, China.
Key Laboratory for Space Bioscience and Biotechnology, Institute of Special Environmental Biophysics, School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, China.
Protist. 2022 Jun;173(3):125881. doi: 10.1016/j.protis.2022.125881. Epub 2022 Apr 18.
A new bakuellid ciliate, Holostichides eastensis nov. spec. isolated from China, is investigated in terms of its morphology, ontogenesis, and molecular phylogenesis. It is characterized by size 150-180 µm × 45-60 µm in vivo; 27-46 macronuclear nodules; cortical granules dark brown, spherical, about 0.5 µm across, clustered in groups and then arranged longitudinally; three frontal cirri with one to four smaller cirri below the middle one, a buccal cirrus, nine to 15 frontoterminal cirri, and midventral complex composed of five to eight cirral pairs and two long midventral rows. The main events during binary fission are as follows: (1) in the proter, the undulating membrane anlage is formed from both the dedifferentiation of old undulating membranes and the basal bodies developing de novo, and the proximal part of the parental adoral zone of membranelles is renewed by a field of basal bodies that originates de novo; (2) in the opisthe, the oral primordium is formed intrakinetally; (3) besides the middle frontal cirrus and buccal cirrus, the FVT-anlagen II produces the extra one to four cirri. Phylogenetic analyses based on SSU rDNA sequence data suggest a close relationship between Holostichides eastensis nov. spec. and its congeners, indicating that the genus Holostichides is monophyletic.
一种新的砂壳纤毛虫，即东方砂壳虫（Holostichides eastensis nov. spec.），从中国分离出来，对其形态、个体发生和分子系统发育进行了研究。其特点是活体大小为 150-180µm×45-60µm；27-46 个大核结；皮质颗粒深褐色，球形，直径约 0.5µm，聚集成群，然后纵向排列；三个额棘，中间一个以下有一到四个较小的棘，一个口棘，9-15 个前口端棘，中腹复合结构由五到八个棘对和两行长的中腹棘组成。二分裂过程中的主要事件如下：（1）在原核期，新的波动膜前体由旧的波动膜的去分化和从头发育的基体形成，亲代口前区的近侧部分通过从头起源的基体场进行更新；（2）在后核期，口原基在动基体内部形成；（3）除了中间额棘和口棘外，FVT 前体 II 还产生一到四个额外的棘。基于 SSU rDNA 序列数据的系统发育分析表明，东方砂壳虫与它的同属种关系密切，表明砂壳虫属是单系的。
