biostudies-literatureUnknown22(1)Han K<h4>Background</h4>The genus Euplotes Ehrenberg, 1830, one of the most complicated and confused taxa, contains about 160 nominal species. It was once proposed to be divided into four genera, two of which were proved to be non-monophyletic. At least 19 new species have been discovered in the past decade, implying that there is a large undiscovered diversity of this genus.<h4>Results</h4>The morphology of two new freshwater euplotid ciliates, Euplotes chongmingensis n. sp. and E. paramieti n. sp., isolated from Shanghai, China, were investigated using live observations, protargol staining, and Chatton-Lwoff silver staining method. Euplotes chongmingensis is characterized by its small size (40-50 × 25-35 μm), about 24 adoral membranelles, 10 frontoventral cirri, two marginal and two caudal ciBMC microbiology133https://www.ebi.ac.uk/biostudies/studies/S-EPMC9109319biostudies-literatureTaxonomy and SSU rRNA gene-based phylogeny of two new Euplotes species from China: E. chongmingensis n. sp. and E. paramieti n. sp. (Protista, Ciliophora).PMC9109319Pan HJiang JHan KfalseTaxonomy and SSU rRNA gene-based phylogeny of two new Euplotes species from China: E. chongmingensis n. sp. and E. paramieti n. sp. (Protista, Ciliophora).<h4>Background</h4>The genus Euplotes Ehrenberg, 1830, one of the most complicated and confused taxa, contains about 160 nominal species. It was once proposed to be divided into four genera, two of which were proved to be non-monophyletic. At least 19 new species have been discovered in the past decade, implying that there is a large undiscovered diversity of this genus.<h4>Results</h4>The morphology of two new freshwater euplotid ciliates, Euplotes chongmingensis n. sp. and E. paramieti n. sp., isolated from Shanghai, China, were investigated using live observations, protargol staining, and Chatton-Lwoff silver staining method. Euplotes chongmingensis is characterized by its small size (40-50 × 25-35 μm), about 24 adoral membranelles, 10 frontoventral cirri, two marginal and two caudal ci2022-01-01T00:00:00Z2022 May2025-04-04T19:31:58.942Z2025-02-19T02:58:01.852ZS-EPMC91093193557818010.1186/s12866-022-02543-9