Systematic positions and taxonomy of two freshwater ciliates found in China, with establishments of one new family and two new species (Ciliophora, Oligohymenophorea)

  • Xiang Wang Laboratory of Protozoology, Harbin Normal University, Harbin 150025, China
  • Lihui Liu Laboratory of Protozoology, Harbin Normal University, Harbin 150025, China
  • Jialu Wang Laboratory of Protozoology, Harbin Normal University, Harbin 150025, China
  • Xiaosong Wang Laboratory of Protozoology, Harbin Normal University, Harbin 150025, China
  • Jiarui Wang Laboratory of Protozoology, Harbin Normal University, Harbin 150025, China
  • Li Wang Laboratory of Protozoology, Harbin Normal University, Harbin 150025, China
  • Lv Zhao Department of Clinical Laboratory, Xian International Medical Center Hospital, Xi’an 710100, China
  • Xuming Pan Laboratory of Protozoology, Harbin Normal University, Harbin 150025, China
DOI: https://doi.org/10.5852/ejt.2025.981.2813
Keywords: Pseudotetrahymena orientalis gen. et sp. nov., Cyclidium paravorax sp. nov., morphology

Abstract

The morphology and molecular phylogeny of two freshwater ciliates, Pseudotetrahymena orientalis gen. et sp. nov. and Cyclidium paravorax sp. nov., collected from Harbin, Northeast China, were investigated based on morphology of live specimens and ciliary pattern; the phylogenetic placements were inferred from the SSU-rRNA gene. Pseudotetrahymenidae fam. nov., assigned to the order Tetrahymenida Fauré-Fremiet in Corliss, 1956, can be distinguished from the other families by its membranelle 2 consisting of several clusters and the shape of the cell. The new species C. paravorax is similar to C. vorax Pan, 2020 in most morphological features except the membranelle 3, which is single-rowed. Phylogenetic analyses based on SSU-rRNA gene sequence indicate that Pseudotetrahymenidae lies in the periphery of the Tetrahymenida clade and forms an independent, fully supported clade. Cyclidium paravorax groups with C. glaucoma Müller, 1773, which supports the assignment of the new species to the genus Cyclidium Müller, 1773.

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Published
2025-03-05
How to Cite
Wang, X., Liu, L., Wang, J., Wang, X., Wang, J., Wang, L., Zhao, L., & Pan, X. (2025). Systematic positions and taxonomy of two freshwater ciliates found in China, with establishments of one new family and two new species (Ciliophora, Oligohymenophorea). European Journal of Taxonomy, 981(1), 1-20. https://doi.org/10.5852/ejt.2025.981.2813
Issue
Vol. 981 (2025)
Section
Research article

Copyright (c) 2025 Xiang Wang, Lihui Liu, Jialu Wang, Xiaosong Wang, Jiarui Wang, Li Wang, Lv Zhao, Xuming Pan

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