TY - JOUR

T1 - Cryptic diversity in Paramecium multimicronucleatum revealed with a polyphasic approach

AU - Melekhin, Maksim

AU - Yakovleva, Yulia

AU - Lebedeva, Natalia

AU - Nekrasova, Irina

AU - Nikitashina, Liubov

AU - Castelli, Michele

AU - Mayen-Estrada, Rosaura

AU - Romanovich, Anna

AU - Petroni, Giulio

AU - Potekhin, Alexey

N1 - Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

PY - 2022/5/5

Y1 - 2022/5/5

N2 - 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.

AB - 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.

KW - ciliates

KW - biogeography

KW - multi-loci phylogenetic analysis

KW - micronucleus

KW - cryptic species

KW - species concept in protists

UR - http://www.scopus.com/inward/record.url?scp=85129397534&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/1a0c21ad-0c48-396c-b84b-552766bceb11/

U2 - 10.3390/microorganisms10050974

DO - 10.3390/microorganisms10050974

M3 - Article

VL - 10

JO - Microorganisms

JF - Microorganisms

SN - 2076-2607

IS - 5

M1 - 974

ER -