Redescription of Dexiotricha colpidiopsis (Kahl, 1926) Jankowski, 1964 (Ciliophora, Oligohymenophorea) from a Hot Spring in Iceland with Identification Key for Dexiotricha species

• Published in: Acta Protozoologica
• Main Authors: Qu, Zhishuai, Groben, René, Marteinsson, Viggó, Agatha, Sabine, Filker, Sabine, Stoeck, Thorsten
• Other Authors: Matvæla- og næringarfræðideild (HÍ), Faculty of Food Science and Nutrition (UI), Heilbrigðisvísindasvið (HÍ), School of Health Sciences (UI), Háskóli Íslands, University of Iceland
• Format: Article in Journal/Newspaper
• Language: English
• Published: Uniwersytet Jagiellonski - Wydawnictwo Uniwersytetu Jagiellonskiego 2018
• Subjects: Dexiotricha; Hot spring; Morphology; Phylogeny; SSU rRNA gene; Hverir; Frumdýr; Gen; Iceland
• Online Access: https://hdl.handle.net/20.500.11815/1090; https://doi.org/10.4467/16890027AP.18.009.8983

Publisher's version (útgefin grein) We isolated an encysted ciliate from a geothermal field in Iceland. The morphological features of this isolate fit the descriptions of Dexiotricha colpidiopsis (Kahl, 1926) Jankowski, 1964 very well. These comprise body shape and size in vivo, the number of somatic kineties, and the positions of macronucleus and contractile vacuole. Using state-of-the-art taxonomic methods, the species is redescribed, including phylogenetic analyses of the small subunit ribosomal RNA (SSU rRNA) gene as molecular marker. In the phylogenetic analyses, D. colpidiopsis clusters with the three available SSU rRNA gene sequences of congeners, suggesting a monophyly of the genus Dexiotricha. Its closest relative in phylogenetic analyses is D. elliptica, which also shows a high morphological similarity. This is the first record of a Dexiotricha species from a hot spring, indicating a wide temperature tolerance of this species at least in the encysted state. The new findings on D. colpidiopsis are included in a briefly revision of the scuticociliate genus Dexiotricha and an identification key to the species. This study was funded by grants awarded to TS by Europlanet 2020 (project 15-EPN-006) and by the Bundesministerium für Bildung und Forschung (BMBF)/Deutsches Zentrum für Luft- und Raumfahrt (DLR, grant 50WB1737). Europlanet 2020 RI has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 654208. Zhishuai Qu received funds from the China Scholarship Council (CSC). We thank Fengchao Li for his support with species identification and Natasa Desnica (Matis) for the trace metal analysis. Peer Reviewed