Cryptic diversity in Paramecium multimicronucleatum revealed with a polyphasic approach

Maksim Melekhin, Yulia Yakovleva, Natalia Lebedeva, Irina Nekrasova, Liubov Nikitashina, Michele Castelli, Rosaura Mayen-Estrada, Anna Romanovich, Giulio Petroni, Alexey Potekhin

Research output: Contribution to journalArticlepeer-review

1 Downloads (Pure)


Paramecium (Ciliophora) systematics is well studied, and about twenty morphological species have been described. The morphological species may include several genetic species. However, molecular phylogenetic analyses revealed that the species diversity within Paramecium could be even higher and has raised a problem of cryptic species whose statuses remain uncertain. In the present study, we provide the morphological and molecular characterization of two novel Paramecium species. While Paramecium lynni n. sp., although morphologically similar to P. multimicronucleatum, is phylogenetically well separated from all other Paramecium species, Paramecium fokini n. sp. appears to be a cryptic sister species to P. multimicronucleatum. The latter two species can be distinguished only by molecular methods. The number and structure of micronuclei, traditionally utilized to discriminate species in Paramecium, vary not only between but also within each of the three studied species and, thus, cannot be considered a reliable feature for species identification. The geographic distribution of the P. multimicronucleatum and P. fokini n. sp. strains do not show defined patterns, still leaving space for a role of the geographic factor in initial speciation in Paramecium. Future findings of new Paramecium species can be predicted from the molecular data, while morphological characteristics appear to be unstable and overlapping at least in some species.
Original languageEnglish
Article number974
StatePublished - 5 May 2022


  • ciliates
  • biogeography
  • multi-loci phylogenetic analysis
  • micronucleus
  • cryptic species
  • species concept in protists


Dive into the research topics of 'Cryptic diversity in Paramecium multimicronucleatum revealed with a polyphasic approach'. Together they form a unique fingerprint.

Cite this