Ewa Przyboś - Academia.edu (original) (raw)

Papers by Ewa Przyboś

Acta Protozoologica, 2011

The representatives of the genus Paramecium are well-studied ciliates and can be used in water qu... more The representatives of the genus Paramecium are well-studied ciliates and can be used in water quality assessment and the determinations of saprobic levels. For these applications, a clear and unambiguous identification of ciliate assemblages is essential, which is typically based on morphological characters requiring a sound taxonomic knowledge and experience in species determination including microscopic identification of both living and stained specimens. Therefore, we developed and applied specific PCR primers for the detection of species belonging to the genus Paramecium and the Paramecium aurelia complex. These primers were successfully tested with different Paramecium species including representatives of the P. aurelia complex as well as closely related species like Frontonia sp. and Tetrahymena sp. in both experimental and environmental samples. These primers can be used in a simultaneous approach achieving fast and reliable results with regard to determination of ciliate co...

Organisms Diversity & Evolution, 2018

Species (or cryptic species) identification in microbial eukaryotes often requires a combined mor... more Species (or cryptic species) identification in microbial eukaryotes often requires a combined morphological and molecular approach, and if possible, mating reaction tests that confirm, for example, that distant populations are in fact one species. We used P. biaurelia (one of the 15 cryptic species of the P. aurelia complex) collected worldwide from 92 sampling points over 62 years and analyzed with the three above mentioned approaches as a model for testing protistan biogeography hypotheses. Our results indicated that despite the large distance between them, most of the studied populations of P. biaurelia do not differ from each other (rDNA fragment), or differ only slightly (COI mtDNA fragment). These results could suggest that in the past, the predecessors of the present P. biaurelia population experienced a bottleneck event, and that its current distribution is the result of recent dispersal by natural or anthropogenic factors. Another possible explanation for the low level of genetic diversity despite the huge distances between the collecting sites could be a slow rate of mutation of the studied DNA fragments, as has been found in some other species of the P. aurelia complex. COI haplotypes determined from samples obtained during field research conducted in 2015-2016 in 28 locations/374 sampling points in southern Poland were shared with other, often distant P. biaurelia populations. In the Kraków area, we found 5 of the 11 currently known COI P. biaurelia haplotypes. In 5 of 7 reservoirs from which P. biaurelia was obtained, two different COI haplotypes were identified.

Species of the Paramecium aurelia complex in the Sącz region

Folia Biologica

Acta Zoologica Cracoviensia - Series B: Invertebrata, 2008

I. INTRODUCTION Józef RAZOWSKI began a long and productive career focused on the systematics of L... more I. INTRODUCTION Józef RAZOWSKI began a long and productive career focused on the systematics of Lepidoptera in 1950, and in 1953 he described first species of Tortricidae-Peronea stachi. Since then he has described 1744 taxa including new genera, new species, and one new tribe. In this catalogue we include all new names published from 1953 to 2006. A list of taxa for a second part, currently in preparation, will start with 2007. RAZOWSKI has cooperated with several specialists who have been included as co-authors of some of the described taxa. These collaborators contributed by collecting material themselves, providing material in their care at various institutions, and/or making significant other contributions to select papers. The list is arranged alphabetically. Each taxon is provided with its reference and type-locality (t.l.) for species or type-species (t.sp.) for genera; generic names of original combinations are included.

Karyological Studies onParamecium(Ciliophora, Protista)

Caryologia, 1990

ABSTRACT Species of the Paramecium aurelia complex, characterized by inbreeding, show differences... more ABSTRACT Species of the Paramecium aurelia complex, characterized by inbreeding, show differences in the number of chromosomes, not only between species, but also within species. It seemed interesting to study the karyologic differentiation in Paramecium jenningsi, a taxonomic species of the genus Paramecium morphologically similar to the P. aurelia species complex, but characterized by outbreeding. Applying the method of semi-thin sections it was found that P. jenninpi strains from India, Uganda, and Madagascar differ karyologically from each other.

Paramecium dodecaurelia strains from Hawaii

Folia biologica, 2003

The presence of Paramecium dodecaurelia (three strains) was recorded in Hawaii.

Habitat of Paramecium biaurelia in Italy, the Island of Elba

Folia biologica, 2001

The new habitat of Paramecium biaurelia was found on the Island Elba.

Paramecium triaurelia and other species of the aurelia complex in the Kaczawskie Mts and Plateau (western Sudeten)

Folia biologica, 1994

The present investigations revealed the occurrence of Paramecium triaurelia on the territory of t... more The present investigations revealed the occurrence of Paramecium triaurelia on the territory of the Kaczawskie Plateau, while its presence was confirmed in the Kaczawskie Mts. In Poland, the presence of this species was recorded only in the Western Sudeten, in spite of many years of investigation. As the result of the studies also the occurrence of P. biaurelia and P. novaurelia was recorded on the territory of the Kaczawskie Mts and the Kaczawskie Plateau.

Species of the Paramecium aurelia complex in the middle Sudeten of Czecho-Slovakia

Folia biologica, 1992

On the investigated territory three species of the complex were identified, namely Paramecium bia... more On the investigated territory three species of the complex were identified, namely Paramecium biaurelia, P. triaurelia, and P. novaurelia. P. novaurelia dominated over the other species with regard to the number of clones established from nature as well as to habitats.

Zooplankton in the artificial pond of the Botanical Garden of the Jagiellonian University in Kraków

Folia biologica, 2001

Paramecium caudatum and the predominant zooplanton organisms were registered in the studied pond ... more Paramecium caudatum and the predominant zooplanton organisms were registered in the studied pond of the Botanical Garden of the Jagiellonian University in Kraków. The finding of Stentor coeruleus indicates an improvement in the environmental conditions in Kraków, connected with the partial liquidation of the huge steelworks.

Three-locus analysis in conjunction with strain crosses confirms the existence of reproductively isolated populations inParamecium jenningsi

Systematics and Biodiversity, 2013

Paramecium jenningsi (Diller & Earl, 1958) was formerly considered to be a species with only ... more Paramecium jenningsi (Diller & Earl, 1958) was formerly considered to be a species with only one syngen (genetic species) based on an inter-strain cross of two strains, cytological analysis, and an investigation of esterases and acid phosphatases. However, the existence of syngens within the species was later suggested by genetic studies, i.e. classical strain crosses of new strains and molecular PCR-based analyses (RAPD, RFLP), as well as by sequencing the H4 gene fragment. This issue still needs to be clarified by the application of molecular markers, genetic tests and cytological preparations. In the present study, we tested 12 strains of P. jenningsi originating from Asia, North America and Africa. Trees reconstructed on the basis of three genome fragments (ITS1-5.8S-ITS2-5’LSU, COI and CytB) show that P. jenningsi is divided into two distinct clusters (PJ1, PJ3) and one branch (PJ2) which correspond to reproductively isolated groups revealed by strain crosses. A study based both on strain crosses and a three-locus comparison gives the opportunity for a more complete identification of the reproductively isolated populations of P. jenningsi and other ciliate species.

Intraspecific Variation of Diagnostic rDNA Genes in Paramecium dodecaurelia, P. tredecaureliaand P. quadecaurelia (Ciliophora: Oligohymenophorea)

Acta Protozool, 2006

Summary. Fragments of the 3'end of SSU rRNA-ITS1 (210bp) and the 5'end of LSU rRNA (350... more Summary. Fragments of the 3'end of SSU rRNA-ITS1 (210bp) and the 5'end of LSU rRNA (350bp) were analysed in a study of intraspecific polymorphism in species of the Paramecium aurelia complex. These species have shown various levels of intraspecific ...

A molecular survey of Paramecium dodecaurelia (Ciliophora, Protozoa) strains from a single pond

Acta Protozoologica, 2009

Paramecium jenningsi complex: existence of three cryptic species confirmed by multi-locus analysis and strain crosses

Folia Biologica, 2017

Paramecium jennngsi (Ciliophora, Protista) is a complex of three cryptic species known from 13 sa... more Paramecium jennngsi (Ciliophora, Protista) is a complex of three cryptic species known from 13 sampling points situated around the world, mainly in the tropics. Two strains recently collected in India were identified as P. bijenningsi and P. trijenningsi from the P. jenningsi complex, based on an analysis of 16 (both nuclear and mitochondrial) loci, strain crosses, and cytological analyses. Current results increase the knowledge about the species range of particular members of the P. jenningsi complex.

Folia Biologica, 2016

The temporal occurrence of some Paramecium aurelia species is still an intriguing problem as cyst... more The temporal occurrence of some Paramecium aurelia species is still an intriguing problem as cysts were never reported to exist in the Paramecium genus. A sequence of species occurrence was studied (by strain crosses and molecular identification) in five water-bodies of the Jagiellonian University Botanical Garden in Kraków in different sampling sites and different seasons of the year. In the current study 20 P. aurelia strains were isolated from collected water samples and identified as P. biaurelia, P. tetraurelia, P. sexaurelia (the first record in Poland), P. novaurelia (the first record in the Botanical Garden). Generally only one species was found in the particular water body in a single sampling point in a given seasonan exception was observed in the case of some strains of P. tetraurelia and P. sexaurelia. The latter species were mostly isolated from two water bodies situated in the Palm Houses (higher temperature preference) and P. biaurelia with P. novaurelia from water bodies located outside (lower temperature preference). Sequencing of the COI mtDNA fragment revealed 9 haplotypes in the studied area which were characteristic for particular species. The most variable species was P. sexaurelia -8 strains studied and 3 haplotypes identified. In contrast, P. novaurelia has only one haplotype for 6 strains collected in different seasons. The present study supports the hypothesis that botanical garden water bodies may be a hot-spot for microbial eukaryotic species such as Paramecium.

Paramecium jenningsicomplex: existence of three cryptic species confirmed by multi-locus analysis and strain crosses

Systematics and Biodiversity, 2016

Ciliates (Protista) have a complex species structure, which means that in several genera the morp... more Ciliates (Protista) have a complex species structure, which means that in several genera the morphological species are differentiated into cryptic species with isolated gene pools (called syngens). Problems of speciation are well known in the genus Paramecium, and especially in the P. aurelia sibling (cryptic) species complex within it. However, the problem of the existence of such species within P. jenningsi was, until recently, still unsolved. Here we present the results of studies based on an analysis of 16 loci (both nuclear and mitochondrial), strain crosses and cytological preparations. The obtained data allowed us not only to study relationships of the P. jenningsi complex and other morphospecies within the Paramecium subgenus, but also to confirm the existence of three isolated reproductive groups within the former P. jenningsi and to propose binominal names for each of them: P. primjenningsi, P. bijenningsi, and P. trijenningsi. In our view, the studied species meet the criteria of a species complex because they can be differentiated based on strain crosses and molecular characteristics, but they cannot be differentiated based on morphological features alone. http://zoobank.org/urn:lsid:zoobank.org:pub:9209CD4C-A255-4A33-BFC1-CE336244C200

Delimiting Species Boundaries within a Paraphyletic Species Complex: Insights from Morphological, Genetic, and Molecular Data on Paramecium sonneborni (Paramecium aurelia species complex, Ciliophora, Protozoa)

Protist, 2015

The demarcation of boundaries between protist species is often problematic because of the absence... more The demarcation of boundaries between protist species is often problematic because of the absence of a uniform species definition, the abundance of cryptic diversity, and the occurrence of convergent morphology. The ciliates belonging to the Paramecium aurelia complex, consisting of 15 species, are a good model for such systematic and evolutionary studies. One member of the complex is P. sonneborni, previously known only from one stand in Texas (USA), but recently found in two new sampling sites in Cyprus (creeks running to Salt Lake and Oroklini Lake near Larnaca). The studied Paramecium sonneborni strains (from the USA and Cyprus) reveal low viability in the F1 and F2 generations of interstrain hybrids and may be an example of ongoing allopatric speciation. Despite its molecular distinctiveness, we postulate that P. sonneborni should remain in the P. aurelia complex, making it a paraphyletic taxon. Morphological studies have revealed that some features of the nuclear apparatus of P. sonneborni correspond to the P. aurelia spp. complex, while others are similar to P. jenningsi and P. schewiakoffi. The observed discordance indicates rapid splitting of the P. aurelia-P. jenningsi-P. schewiakoffi group, in which genetic, morphological, and molecular boundaries between species are not congruent.

Comparison of the evolutionary distances among syngens and sibling species of Paramecium

Molecular phylogenetics and evolution, 2006

The morphospecies of the genus Paramecium have several mating type groups, so-called syngens, com... more The morphospecies of the genus Paramecium have several mating type groups, so-called syngens, composed of cells of complementary mating types. The Paramecium aurelia complex is composed of 15 sibling species assigned to the species from the syngen. To increase our understanding of the evolutionary relationships among syngen and sibling species of the genus Paramecium, we investigated the gene sequences of cytosol-type hsp70 from 7 syngens of Paramecium caudatum and 15 sibling species of P. aurelia. Molecular phylogenetic trees indicated that the P. aurelia complex could be divided into four lineages and separated into each sibling species. However, we did not find any obvious genetic distance among syngens of P. caudatum, and they could only be separated into two closely related groups. These results indicated that the concept of syngens in P. caudatum differs quite markedly from that of the P. aurelia complex. In addition, we also discuss the relationships among these species and o...

Paramecium decaurelia and Paramecium dodecaurelia from the P. aurelia spp. complex in Japan

Folia biologica, 2003

The presence of Paramecium decaurelia (three strains) and Paramecium dodecaurelia (two strains) w... more The presence of Paramecium decaurelia (three strains) and Paramecium dodecaurelia (two strains) were recorded in Japan, for the first time in this country and outside the USA.

Acta Protozoologica, 2011

The representatives of the genus Paramecium are well-studied ciliates and can be used in water qu... more The representatives of the genus Paramecium are well-studied ciliates and can be used in water quality assessment and the determinations of saprobic levels. For these applications, a clear and unambiguous identification of ciliate assemblages is essential, which is typically based on morphological characters requiring a sound taxonomic knowledge and experience in species determination including microscopic identification of both living and stained specimens. Therefore, we developed and applied specific PCR primers for the detection of species belonging to the genus Paramecium and the Paramecium aurelia complex. These primers were successfully tested with different Paramecium species including representatives of the P. aurelia complex as well as closely related species like Frontonia sp. and Tetrahymena sp. in both experimental and environmental samples. These primers can be used in a simultaneous approach achieving fast and reliable results with regard to determination of ciliate co...

Organisms Diversity & Evolution, 2018

Species (or cryptic species) identification in microbial eukaryotes often requires a combined mor... more Species (or cryptic species) identification in microbial eukaryotes often requires a combined morphological and molecular approach, and if possible, mating reaction tests that confirm, for example, that distant populations are in fact one species. We used P. biaurelia (one of the 15 cryptic species of the P. aurelia complex) collected worldwide from 92 sampling points over 62 years and analyzed with the three above mentioned approaches as a model for testing protistan biogeography hypotheses. Our results indicated that despite the large distance between them, most of the studied populations of P. biaurelia do not differ from each other (rDNA fragment), or differ only slightly (COI mtDNA fragment). These results could suggest that in the past, the predecessors of the present P. biaurelia population experienced a bottleneck event, and that its current distribution is the result of recent dispersal by natural or anthropogenic factors. Another possible explanation for the low level of genetic diversity despite the huge distances between the collecting sites could be a slow rate of mutation of the studied DNA fragments, as has been found in some other species of the P. aurelia complex. COI haplotypes determined from samples obtained during field research conducted in 2015-2016 in 28 locations/374 sampling points in southern Poland were shared with other, often distant P. biaurelia populations. In the Kraków area, we found 5 of the 11 currently known COI P. biaurelia haplotypes. In 5 of 7 reservoirs from which P. biaurelia was obtained, two different COI haplotypes were identified.

Species of the Paramecium aurelia complex in the Sącz region

Folia Biologica

Acta Zoologica Cracoviensia - Series B: Invertebrata, 2008

I. INTRODUCTION Józef RAZOWSKI began a long and productive career focused on the systematics of L... more I. INTRODUCTION Józef RAZOWSKI began a long and productive career focused on the systematics of Lepidoptera in 1950, and in 1953 he described first species of Tortricidae-Peronea stachi. Since then he has described 1744 taxa including new genera, new species, and one new tribe. In this catalogue we include all new names published from 1953 to 2006. A list of taxa for a second part, currently in preparation, will start with 2007. RAZOWSKI has cooperated with several specialists who have been included as co-authors of some of the described taxa. These collaborators contributed by collecting material themselves, providing material in their care at various institutions, and/or making significant other contributions to select papers. The list is arranged alphabetically. Each taxon is provided with its reference and type-locality (t.l.) for species or type-species (t.sp.) for genera; generic names of original combinations are included.

Karyological Studies onParamecium(Ciliophora, Protista)

Caryologia, 1990

ABSTRACT Species of the Paramecium aurelia complex, characterized by inbreeding, show differences... more ABSTRACT Species of the Paramecium aurelia complex, characterized by inbreeding, show differences in the number of chromosomes, not only between species, but also within species. It seemed interesting to study the karyologic differentiation in Paramecium jenningsi, a taxonomic species of the genus Paramecium morphologically similar to the P. aurelia species complex, but characterized by outbreeding. Applying the method of semi-thin sections it was found that P. jenninpi strains from India, Uganda, and Madagascar differ karyologically from each other.

Paramecium dodecaurelia strains from Hawaii

Folia biologica, 2003

The presence of Paramecium dodecaurelia (three strains) was recorded in Hawaii.

Habitat of Paramecium biaurelia in Italy, the Island of Elba

Folia biologica, 2001

The new habitat of Paramecium biaurelia was found on the Island Elba.

Paramecium triaurelia and other species of the aurelia complex in the Kaczawskie Mts and Plateau (western Sudeten)

Folia biologica, 1994

The present investigations revealed the occurrence of Paramecium triaurelia on the territory of t... more The present investigations revealed the occurrence of Paramecium triaurelia on the territory of the Kaczawskie Plateau, while its presence was confirmed in the Kaczawskie Mts. In Poland, the presence of this species was recorded only in the Western Sudeten, in spite of many years of investigation. As the result of the studies also the occurrence of P. biaurelia and P. novaurelia was recorded on the territory of the Kaczawskie Mts and the Kaczawskie Plateau.

Species of the Paramecium aurelia complex in the middle Sudeten of Czecho-Slovakia

Folia biologica, 1992

On the investigated territory three species of the complex were identified, namely Paramecium bia... more On the investigated territory three species of the complex were identified, namely Paramecium biaurelia, P. triaurelia, and P. novaurelia. P. novaurelia dominated over the other species with regard to the number of clones established from nature as well as to habitats.

Zooplankton in the artificial pond of the Botanical Garden of the Jagiellonian University in Kraków

Folia biologica, 2001

Paramecium caudatum and the predominant zooplanton organisms were registered in the studied pond ... more Paramecium caudatum and the predominant zooplanton organisms were registered in the studied pond of the Botanical Garden of the Jagiellonian University in Kraków. The finding of Stentor coeruleus indicates an improvement in the environmental conditions in Kraków, connected with the partial liquidation of the huge steelworks.

Three-locus analysis in conjunction with strain crosses confirms the existence of reproductively isolated populations inParamecium jenningsi

Systematics and Biodiversity, 2013

Paramecium jenningsi (Diller & Earl, 1958) was formerly considered to be a species with only ... more Paramecium jenningsi (Diller & Earl, 1958) was formerly considered to be a species with only one syngen (genetic species) based on an inter-strain cross of two strains, cytological analysis, and an investigation of esterases and acid phosphatases. However, the existence of syngens within the species was later suggested by genetic studies, i.e. classical strain crosses of new strains and molecular PCR-based analyses (RAPD, RFLP), as well as by sequencing the H4 gene fragment. This issue still needs to be clarified by the application of molecular markers, genetic tests and cytological preparations. In the present study, we tested 12 strains of P. jenningsi originating from Asia, North America and Africa. Trees reconstructed on the basis of three genome fragments (ITS1-5.8S-ITS2-5’LSU, COI and CytB) show that P. jenningsi is divided into two distinct clusters (PJ1, PJ3) and one branch (PJ2) which correspond to reproductively isolated groups revealed by strain crosses. A study based both on strain crosses and a three-locus comparison gives the opportunity for a more complete identification of the reproductively isolated populations of P. jenningsi and other ciliate species.

Intraspecific Variation of Diagnostic rDNA Genes in Paramecium dodecaurelia, P. tredecaureliaand P. quadecaurelia (Ciliophora: Oligohymenophorea)

Acta Protozool, 2006

Summary. Fragments of the 3'end of SSU rRNA-ITS1 (210bp) and the 5'end of LSU rRNA (350... more Summary. Fragments of the 3'end of SSU rRNA-ITS1 (210bp) and the 5'end of LSU rRNA (350bp) were analysed in a study of intraspecific polymorphism in species of the Paramecium aurelia complex. These species have shown various levels of intraspecific ...

A molecular survey of Paramecium dodecaurelia (Ciliophora, Protozoa) strains from a single pond

Acta Protozoologica, 2009

Paramecium jenningsi complex: existence of three cryptic species confirmed by multi-locus analysis and strain crosses

Folia Biologica, 2017

Paramecium jennngsi (Ciliophora, Protista) is a complex of three cryptic species known from 13 sa... more Paramecium jennngsi (Ciliophora, Protista) is a complex of three cryptic species known from 13 sampling points situated around the world, mainly in the tropics. Two strains recently collected in India were identified as P. bijenningsi and P. trijenningsi from the P. jenningsi complex, based on an analysis of 16 (both nuclear and mitochondrial) loci, strain crosses, and cytological analyses. Current results increase the knowledge about the species range of particular members of the P. jenningsi complex.

Folia Biologica, 2016

The temporal occurrence of some Paramecium aurelia species is still an intriguing problem as cyst... more The temporal occurrence of some Paramecium aurelia species is still an intriguing problem as cysts were never reported to exist in the Paramecium genus. A sequence of species occurrence was studied (by strain crosses and molecular identification) in five water-bodies of the Jagiellonian University Botanical Garden in Kraków in different sampling sites and different seasons of the year. In the current study 20 P. aurelia strains were isolated from collected water samples and identified as P. biaurelia, P. tetraurelia, P. sexaurelia (the first record in Poland), P. novaurelia (the first record in the Botanical Garden). Generally only one species was found in the particular water body in a single sampling point in a given seasonan exception was observed in the case of some strains of P. tetraurelia and P. sexaurelia. The latter species were mostly isolated from two water bodies situated in the Palm Houses (higher temperature preference) and P. biaurelia with P. novaurelia from water bodies located outside (lower temperature preference). Sequencing of the COI mtDNA fragment revealed 9 haplotypes in the studied area which were characteristic for particular species. The most variable species was P. sexaurelia -8 strains studied and 3 haplotypes identified. In contrast, P. novaurelia has only one haplotype for 6 strains collected in different seasons. The present study supports the hypothesis that botanical garden water bodies may be a hot-spot for microbial eukaryotic species such as Paramecium.

Paramecium jenningsicomplex: existence of three cryptic species confirmed by multi-locus analysis and strain crosses

Systematics and Biodiversity, 2016

Ciliates (Protista) have a complex species structure, which means that in several genera the morp... more Ciliates (Protista) have a complex species structure, which means that in several genera the morphological species are differentiated into cryptic species with isolated gene pools (called syngens). Problems of speciation are well known in the genus Paramecium, and especially in the P. aurelia sibling (cryptic) species complex within it. However, the problem of the existence of such species within P. jenningsi was, until recently, still unsolved. Here we present the results of studies based on an analysis of 16 loci (both nuclear and mitochondrial), strain crosses and cytological preparations. The obtained data allowed us not only to study relationships of the P. jenningsi complex and other morphospecies within the Paramecium subgenus, but also to confirm the existence of three isolated reproductive groups within the former P. jenningsi and to propose binominal names for each of them: P. primjenningsi, P. bijenningsi, and P. trijenningsi. In our view, the studied species meet the criteria of a species complex because they can be differentiated based on strain crosses and molecular characteristics, but they cannot be differentiated based on morphological features alone. http://zoobank.org/urn:lsid:zoobank.org:pub:9209CD4C-A255-4A33-BFC1-CE336244C200

Delimiting Species Boundaries within a Paraphyletic Species Complex: Insights from Morphological, Genetic, and Molecular Data on Paramecium sonneborni (Paramecium aurelia species complex, Ciliophora, Protozoa)

Protist, 2015

The demarcation of boundaries between protist species is often problematic because of the absence... more The demarcation of boundaries between protist species is often problematic because of the absence of a uniform species definition, the abundance of cryptic diversity, and the occurrence of convergent morphology. The ciliates belonging to the Paramecium aurelia complex, consisting of 15 species, are a good model for such systematic and evolutionary studies. One member of the complex is P. sonneborni, previously known only from one stand in Texas (USA), but recently found in two new sampling sites in Cyprus (creeks running to Salt Lake and Oroklini Lake near Larnaca). The studied Paramecium sonneborni strains (from the USA and Cyprus) reveal low viability in the F1 and F2 generations of interstrain hybrids and may be an example of ongoing allopatric speciation. Despite its molecular distinctiveness, we postulate that P. sonneborni should remain in the P. aurelia complex, making it a paraphyletic taxon. Morphological studies have revealed that some features of the nuclear apparatus of P. sonneborni correspond to the P. aurelia spp. complex, while others are similar to P. jenningsi and P. schewiakoffi. The observed discordance indicates rapid splitting of the P. aurelia-P. jenningsi-P. schewiakoffi group, in which genetic, morphological, and molecular boundaries between species are not congruent.

Comparison of the evolutionary distances among syngens and sibling species of Paramecium

Molecular phylogenetics and evolution, 2006

The morphospecies of the genus Paramecium have several mating type groups, so-called syngens, com... more The morphospecies of the genus Paramecium have several mating type groups, so-called syngens, composed of cells of complementary mating types. The Paramecium aurelia complex is composed of 15 sibling species assigned to the species from the syngen. To increase our understanding of the evolutionary relationships among syngen and sibling species of the genus Paramecium, we investigated the gene sequences of cytosol-type hsp70 from 7 syngens of Paramecium caudatum and 15 sibling species of P. aurelia. Molecular phylogenetic trees indicated that the P. aurelia complex could be divided into four lineages and separated into each sibling species. However, we did not find any obvious genetic distance among syngens of P. caudatum, and they could only be separated into two closely related groups. These results indicated that the concept of syngens in P. caudatum differs quite markedly from that of the P. aurelia complex. In addition, we also discuss the relationships among these species and o...

Paramecium decaurelia and Paramecium dodecaurelia from the P. aurelia spp. complex in Japan

Folia biologica, 2003

The presence of Paramecium decaurelia (three strains) and Paramecium dodecaurelia (two strains) w... more The presence of Paramecium decaurelia (three strains) and Paramecium dodecaurelia (two strains) were recorded in Japan, for the first time in this country and outside the USA.