The journal publish current and comprehensive, experimental, and theoretical papers across the breadth of protistology, and cell biology of Eukaryote microorganisms including: behaviour, biochemistry, molecular biology, development, ecology, genetics, parasitology, physiology, photobiology, systematics, phylogeny, ultrastructure.
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Description
ISSN: 0065-1583
eISSN: 1689-0027
MNiSW points: 40
UIC ID: 312
DOI: 10.4467/16890027AP
Editorial team
Publisher
Uniwersytet Jagielloński w Krakowie
Affiliation
Jagiellonian University in Kraków
Publication date: 05.03.2024
John R. Dolan, Eun Jin Yang, Jong-Kuk Moon
Acta Protozoologica, Volume 63, 2024, pp. 1 - 7
https://doi.org/10.4467/16890027AP.24.001.19426We recently documented the existence of 26 different forms of Papulifères, presumptive ciliate cysts, from plankton net tow material of the Chukchi Sea gathered in 2015, 2021, and 2022. The forms appeared to be rare, found in only 7 of the 308 samples taken in annual August surveys from 2010 to 2022. Thus, we were surprised to find them relatively common and widespread in samples gathered in August of 2023. We found 18 different Papulifére forms, 8 of which appear to be new forms, in samples from 19 of the 36 stations sampled. They were found in localities ranging from 70.5°N to 80°N. Here we report on these Papulifére forms found in 2023, providing information on morphologies and geographical distributions. With this report we have expanded the catalogue of observed Papulifére, and photographed, forms of the Chukchi Sea to a grand total of 34 of morphologically distinct forms. However, we continue to urge caution in assigning a ciliate identity to any given Papulifére form in the absence of corroborating data.
John R. Dolan, Eun Jin Yang, Jong-Kuk Moon
Acta Protozoologica, Volume 63, 2024, pp. 1 - 7
https://doi.org/10.4467/16890027AP.24.001.19426We recently documented the existence of 26 different forms of Papulifères, presumptive ciliate cysts, from plankton net tow material of the Chukchi Sea gathered in 2015, 2021, and 2022. The forms appeared to be rare, found in only 7 of the 308 samples taken in annual August surveys from 2010 to 2022. Thus, we were surprised to find them relatively common and widespread in samples gathered in August of 2023. We found 18 different Papulifére forms, 8 of which appear to be new forms, in samples from 19 of the 36 stations sampled. They were found in localities ranging from 70.5°N to 80°N. Here we report on these Papulifére forms found in 2023, providing information on morphologies and geographical distributions. With this report we have expanded the catalogue of observed Papulifére, and photographed, forms of the Chukchi Sea to a grand total of 34 of morphologically distinct forms. However, we continue to urge caution in assigning a ciliate identity to any given Papulifére form in the absence of corroborating data.
Publication date: 2023
Editor-in-Chief: Krzysztof Wiąckowski
John R. Dolan, Eun Jin Yang, Jong-Kuk Moon
Acta Protozoologica, Volume 62, 2023, pp. 1 - 14
https://doi.org/10.4467/16890027AP.23.001.17690In the early 20th century, Alphonse Meunier described "Papulifères" as a group of enigmatic forms of unknown taxonomic affinity characterized by possessing a hyaline pimple, a "papula". In the early 1980's Papulifères were equated with cysts of tintinnid ciliates. The most conspicuous forms, the large Fusopsis, have been widely found, and are now known to resemble the cyst of a certain species of oligotrich ciliate (i.e., Cyrtostrombidium boreale). Thus today, Papulifère forms are often assumed to be cysts of oligotrich ciliates. Here we report on 26 Papulifère forms, of more or less distinct morphologies, found in the plankton of the Chukchi Sea. We found forms resembling some of those described by Meunier, and recorded here for the first time since Meunier's reports, and others that do not resemble any of Meunier's Papulifères. Here, we first review the literature on Papulifères, then we present the surprising variety of forms we found in Chukchi Sea, and for some, we provide for the first time data on morphological variability. With this report we have expanded the catalogue of observed Papulifère forms and documented variability in the dimensions of some morphotypes. However, we urge caution in assigning a ciliate species name to any given Papulifère form in the absence of corroborating data. There is a need for observational and/or sequence-based data to elucidate the identity of Papulifère forms.
Rasha H. Solimam, Alexandra Martin-Ramirez, Jose M. Rubio, Eman A. Khalifa, Bushra E. Hussein, Maha M. Wahab, Marta Lanza, Yousry A. Hawash
Acta Protozoologica, Volume 62, 2023, pp. 15 - 23
https://doi.org/10.4467/16890027AP.23.002.17903Malaria diagnosis continues to be one of the most important steps in the cycle of control specially in endemic countries with low parasitic load infections. Loop-mediated isothermal amplification (LAMP) and ultrasensitive PCR (Us-PCR) are two promising candidates for malaria diagnosis. A cross sectional study performed at King Faisal Hospital, Taif KSA involved patients suffering from signs and symptoms suggesting of malaria, 35 blood samples diagnosed by Nested Multiplex PCR as a reference method (13 P. falciparum, 17 P. vivax, 3 mixed P. falciparum and P. vivax) plus two negative controls were selected to be included in this study to analyse the performance of two LAMP methods (LAMP OptiGene® and LAMP WarmStart®) and two ultrasensitive PCRs (Us-PCR TARE-2 and Us-PCR Var-ATS). LAMP OptiGene® and LAMP WarmStart® performances were identical and better than the performance of Us PCR TARE 2 and Us-PCR var-ATS for P. falciparum, achieving 93.75% sensitivity, 100% specificity and 97.17% accuracy versus 87.5% sensitivity, 100% specificity and 94.29% accuracy for the Us PCR TARE 2 and 81.25% sensitivity, 94.74% specificity and 88.57% accuracy for the Us PCR var-ATS respectively. In P. vivax diagnosis LAMP OptiGene® performed excellently with 100% sensitivity, specificity, and accuracy while LAMP WarmStart® and Us-PCR Cox1 achieved 100% sensitivity, specificity 93.33% and 97.14% accuracy. The study results highlighted the benefits of using LAMP techniques for field diagnosis of malaria in different settings where the need for a more sensitive and reliable molecular tool is mandatory but at the same time removing the high cost, long turnaround time and the need of highly specialized trained technicians to perform more sophisticated molecular techniques.
Ronnilda Maria Gonçalves Araujo, Guilherme Sampaio Cabral, Fabiano Corrêa, André Ricardo Ghidini
Acta Protozoologica, Volume 62, 2023, pp. 25 - 37
https://doi.org/10.4467/16890027AP.23.003.18283We investigated the diversity of testate amoebae in an urban stream located within the Igarapé São Francisco Environmental Protection Area in Acre, northern Brazil, during the dry season, and evaluated the factors mediating the structure of this protist community. We collected 108 water samples for the analysis of the testate amoeba community and the limnological variables at six sampling points on the stream, between July and September 2018. We used a Redundancy Analysis (RDA) to verify the influence of environmental variables on the protist community. We recorded 76 species of testate amoebae from eight families, with most records from the families Difflugiidae, Arcellidae, Centropydae and Netzeliidae. More than half (49) of the species were recorded in Acre for the first time. The abundance of the amoebae of the family Trigonopiridae was regulated by the dissolved oxygen concentrations and the pH, while that of the Netzeliidae, Difflugiidae and Lesquereusidae was influenced by the pH, chloride concentrations, and the depth and transparency of the water. In the case of the family Arcellidae, abundance was determined by the turbidity and transparency of the water and the nitrate concentrations, while that of Centropyxis sp. was associated with the concentrations of thermotolerant coliforms. These findings indicate that, while the São Francisco stream is subject to anthropogenic impacts, it still presents adequate conditions for these organisms in some of its stretches. The abundance of these amoebae was influenced primarily by the productivity of the system, as indicated by the high protist densities recorded in the areas in which primary productivity was highest. These findings support the use of these protists in studies that investigate the most appropriate indicator organisms that respond to anthropogenic impacts and shifts in environmental quality.The results of the present study demonstrated the importance of this aquatic ecosystem for the biodiversity of the study area, and the need to further expand our knowledge on the adaptations and interactions of the aquatic communities of the Amazon region.
Shuntaro Hakozaki, Hiroki Yamanobe, Kazuma Yabuki, Taiga Shimizu, Takeru Saito, Ryota Saito, Futoshi Suizu, Tomohiro Suzuki, Yoichiro Sogame
Acta Protozoologica, Volume 62, 2023, pp. 39 - 44
https://doi.org/10.4467/16890027AP.23.004.18421Resting cyst formation is a crucial process of cryptobiosis in protists. In colpodid ciliates, cyst formation is accompanied by large-scale morphological changes such as changes of cell shape, resorption of cilia, and formation of a cyst wall; additionally, the cell cycle is arrested. These changes provide acquired tolerance against environmental stresses. During cyst formation, mitochondrial membrane potential is reduced and the level of the ATP synthase beta chain is suppressed, strongly indicating that metabolism has ceased. Here, however, we show that ATP levels are elevated during the initial phases of encystment implying that metabolism may not be completely suppressed. This finding suggests another aspect of resting cyst formation that is not applicable to cryptobiosis.
Junlin WU, Jiaqi Yin, Zixiang Xu, Yingli Liu, Huanyong Qin, Xin Sheng
Acta Protozoologica, Volume 62, 2023, pp. 45 - 56
https://doi.org/10.4467/16890027AP.23.005.18868Clément Duckert, Evelyn Greeves, Quentin Blandenier, Richard J. Payne, Edward A. D. Mitchell
Acta Protozoologica, Volume 62, 2023, pp. 57 - 63
https://doi.org/10.4467/16890027AP.23.006.19011John R. Dolan, Eun Jin Yang, Jong-Kuk Moon
Acta Protozoologica, Volume 62, 2023, pp. 1 - 14
https://doi.org/10.4467/16890027AP.23.001.17690In the early 20th century, Alphonse Meunier described "Papulifères" as a group of enigmatic forms of unknown taxonomic affinity characterized by possessing a hyaline pimple, a "papula". In the early 1980's Papulifères were equated with cysts of tintinnid ciliates. The most conspicuous forms, the large Fusopsis, have been widely found, and are now known to resemble the cyst of a certain species of oligotrich ciliate (i.e., Cyrtostrombidium boreale). Thus today, Papulifère forms are often assumed to be cysts of oligotrich ciliates. Here we report on 26 Papulifère forms, of more or less distinct morphologies, found in the plankton of the Chukchi Sea. We found forms resembling some of those described by Meunier, and recorded here for the first time since Meunier's reports, and others that do not resemble any of Meunier's Papulifères. Here, we first review the literature on Papulifères, then we present the surprising variety of forms we found in Chukchi Sea, and for some, we provide for the first time data on morphological variability. With this report we have expanded the catalogue of observed Papulifère forms and documented variability in the dimensions of some morphotypes. However, we urge caution in assigning a ciliate species name to any given Papulifère form in the absence of corroborating data. There is a need for observational and/or sequence-based data to elucidate the identity of Papulifère forms.
Rasha H. Solimam, Alexandra Martin-Ramirez, Jose M. Rubio, Eman A. Khalifa, Bushra E. Hussein, Maha M. Wahab, Marta Lanza, Yousry A. Hawash
Acta Protozoologica, Volume 62, 2023, pp. 15 - 23
https://doi.org/10.4467/16890027AP.23.002.17903Malaria diagnosis continues to be one of the most important steps in the cycle of control specially in endemic countries with low parasitic load infections. Loop-mediated isothermal amplification (LAMP) and ultrasensitive PCR (Us-PCR) are two promising candidates for malaria diagnosis. A cross sectional study performed at King Faisal Hospital, Taif KSA involved patients suffering from signs and symptoms suggesting of malaria, 35 blood samples diagnosed by Nested Multiplex PCR as a reference method (13 P. falciparum, 17 P. vivax, 3 mixed P. falciparum and P. vivax) plus two negative controls were selected to be included in this study to analyse the performance of two LAMP methods (LAMP OptiGene® and LAMP WarmStart®) and two ultrasensitive PCRs (Us-PCR TARE-2 and Us-PCR Var-ATS). LAMP OptiGene® and LAMP WarmStart® performances were identical and better than the performance of Us PCR TARE 2 and Us-PCR var-ATS for P. falciparum, achieving 93.75% sensitivity, 100% specificity and 97.17% accuracy versus 87.5% sensitivity, 100% specificity and 94.29% accuracy for the Us PCR TARE 2 and 81.25% sensitivity, 94.74% specificity and 88.57% accuracy for the Us PCR var-ATS respectively. In P. vivax diagnosis LAMP OptiGene® performed excellently with 100% sensitivity, specificity, and accuracy while LAMP WarmStart® and Us-PCR Cox1 achieved 100% sensitivity, specificity 93.33% and 97.14% accuracy. The study results highlighted the benefits of using LAMP techniques for field diagnosis of malaria in different settings where the need for a more sensitive and reliable molecular tool is mandatory but at the same time removing the high cost, long turnaround time and the need of highly specialized trained technicians to perform more sophisticated molecular techniques.
Ronnilda Maria Gonçalves Araujo, Guilherme Sampaio Cabral, Fabiano Corrêa, André Ricardo Ghidini
Acta Protozoologica, Volume 62, 2023, pp. 25 - 37
https://doi.org/10.4467/16890027AP.23.003.18283We investigated the diversity of testate amoebae in an urban stream located within the Igarapé São Francisco Environmental Protection Area in Acre, northern Brazil, during the dry season, and evaluated the factors mediating the structure of this protist community. We collected 108 water samples for the analysis of the testate amoeba community and the limnological variables at six sampling points on the stream, between July and September 2018. We used a Redundancy Analysis (RDA) to verify the influence of environmental variables on the protist community. We recorded 76 species of testate amoebae from eight families, with most records from the families Difflugiidae, Arcellidae, Centropydae and Netzeliidae. More than half (49) of the species were recorded in Acre for the first time. The abundance of the amoebae of the family Trigonopiridae was regulated by the dissolved oxygen concentrations and the pH, while that of the Netzeliidae, Difflugiidae and Lesquereusidae was influenced by the pH, chloride concentrations, and the depth and transparency of the water. In the case of the family Arcellidae, abundance was determined by the turbidity and transparency of the water and the nitrate concentrations, while that of Centropyxis sp. was associated with the concentrations of thermotolerant coliforms. These findings indicate that, while the São Francisco stream is subject to anthropogenic impacts, it still presents adequate conditions for these organisms in some of its stretches. The abundance of these amoebae was influenced primarily by the productivity of the system, as indicated by the high protist densities recorded in the areas in which primary productivity was highest. These findings support the use of these protists in studies that investigate the most appropriate indicator organisms that respond to anthropogenic impacts and shifts in environmental quality.The results of the present study demonstrated the importance of this aquatic ecosystem for the biodiversity of the study area, and the need to further expand our knowledge on the adaptations and interactions of the aquatic communities of the Amazon region.
Shuntaro Hakozaki, Hiroki Yamanobe, Kazuma Yabuki, Taiga Shimizu, Takeru Saito, Ryota Saito, Futoshi Suizu, Tomohiro Suzuki, Yoichiro Sogame
Acta Protozoologica, Volume 62, 2023, pp. 39 - 44
https://doi.org/10.4467/16890027AP.23.004.18421Resting cyst formation is a crucial process of cryptobiosis in protists. In colpodid ciliates, cyst formation is accompanied by large-scale morphological changes such as changes of cell shape, resorption of cilia, and formation of a cyst wall; additionally, the cell cycle is arrested. These changes provide acquired tolerance against environmental stresses. During cyst formation, mitochondrial membrane potential is reduced and the level of the ATP synthase beta chain is suppressed, strongly indicating that metabolism has ceased. Here, however, we show that ATP levels are elevated during the initial phases of encystment implying that metabolism may not be completely suppressed. This finding suggests another aspect of resting cyst formation that is not applicable to cryptobiosis.
Junlin WU, Jiaqi Yin, Zixiang Xu, Yingli Liu, Huanyong Qin, Xin Sheng
Acta Protozoologica, Volume 62, 2023, pp. 45 - 56
https://doi.org/10.4467/16890027AP.23.005.18868Clément Duckert, Evelyn Greeves, Quentin Blandenier, Richard J. Payne, Edward A. D. Mitchell
Acta Protozoologica, Volume 62, 2023, pp. 57 - 63
https://doi.org/10.4467/16890027AP.23.006.19011Publication date: 2022
Editor-in-Chief: Krzysztof Wiąckowski
Yasmin de Góes Cohn Freitas, Beatriz Rodrigues D’Oliveira Ramos, Viviane Bernardes dos Santos Miranda, Yemna Gomes da Silva, Gabriela Silva Sampaio, Letícia da Silva Nascimento, Christina Wyss Castelo Branco
Acta Protozoologica, Volume 61, 2022, pp. 1 - 21
https://doi.org/10.4467/16890027AP.22.001.15671Testate amoebae (TA) are unicellular protozoans enclosed in a test capable of indicating a wide variety of environmental conditions. Among others, characteristics such as short life cycle, great sensitivity and worldwide distribution makes them adequate bioindicators. As a complement to physical and chemical measurements, biomonitoring can be a cheaper and fastest way of environmental monitoring. This research sought to evaluate the extent of TA use in biomonitoring and the responses given by them to environmental features. The research was conducted in Scielo, Science Direct, Online Library, Google Scholar and Capes Journal Portal and yielded 211 papers. TA bioindication is able to provide information on metal, trace element and atmospheric pollution, and to point out different trophic states, pH, and evidence on characteristics of hydrology. Further, TA can be used in paleoenvironmental reconstruction as they reflect climate, volcanic and even sea level change phenomena. Sometimes, together with other organisms in environmental analysis, they have shown to be an important complement to biomonitoring. Additionally, a functional traits approach has been recently included as a promising tool. Methodological adjustments that have been conducted throughout the years are allowing TA use to be more reliable and precise. This review provides insight on the many possible functions of TA in bioindication studies, highlighting their wide use as bioindicators.
Eman S. El-Wakil, Eman Ali Mohamed, Eman Ahmed El-Wakil, Tarek S. AbouShousha, Neimat Mousa Amer
Acta Protozoologica, Volume 61, 2022, pp. 23 - 34
https://doi.org/10.4467/16890027AP.22.002.16205Cryptosporidium parvum, an Apicomplexan parasite, is an important cause of diarrheal disease, especially in immunodeficient hosts. Nevertheless, there is no entirely successful therapeutic agent against cryptosporidiosis to date. Hence, this study aims to test the potential prophylactic and therapeutic effect of Camellia sinensis (green tea extract) in dexamethasone immunosuppressed mice versus the nowadays used drug, Nitazoxanide (NTZ). Parasitological and molecular methods were used to characterize Cryptosporidium oocysts before infection. Fifty bred female Swiss Albino mice were divided into 5 groups; group I (GI)(GTP): immunosuppressed and prophylactically treated with green tea extract for 5 days prior to infection, group II (GII)(GTT): immunosuppressed, infected with Cryptosporidium parvum and treated with green tea extract, group III (GIII)(NT): immunosuppressed, infected and treated with NTZ, group IV (GIV)(PC): immunosuppressed and infected (Positive control), group V (GV)(NC): immunosuppressed and non-infected (Negative control). Furthermore, parasitological examination for oocysts in the stool, and histopathological examination for the small intestine and liver specimens were performed for the study groups. Cryptosporidium oocysts used for induction of infection proved to be Cryptosporidium parvum genotype 2. Moreover, a significant oocyst reduction in fecal samples correlated with an improvement of histopathological changes in the small intestinal and liver tissues in GI(GTP), GII (GTT) and GIII(NT) groups. Besides, the GII(GTT) group showed the best improvement in parasitological and histopathological parameters among the test groups. This study revealed that Camellia sinensis (green tea extract) has potential activity against cryptosporidiosis and could serve as a promising prophylactic and therapeutic anti-cryptosporidial agent.
Ľubomír Rajter, Borong Lu, Erika Rassoshanska, Micah Dunthorn
Acta Protozoologica, Volume 61, 2022, pp. 35 - 46
https://doi.org/10.4467/16890027AP.22.005.16236Ciliates have a long history of being central in evolutionary and ecological studies on eukaryotic microorganisms. Although thousands of species have been discovered, their total diversity still remains unknown. Here, we will discuss two unsolved problems that hinder the further exploration of ciliate diversity at the species level, and potential solutions to these problems are proposed. First, ciliate morphospecies are difficult to identify because the different silver stains are not scalable (they do not represent high-throughput methods) and basic supplies are lacking (e.g., protargol); a solution may be the development of fluorescent staining techniques. Second, ciliate phylogenetic species are difficult to identify because of extensive paralogy in nuclear-protein-coding genes; a solution may be to concentrate on sequencing mitochondrial genomes. These two approaches could be integrated into a high-throughput fluorescent-single-cell sorting and mitochondrial genomes sequencing process that would enable the observation and better understanding of ciliate species on a massive scale.
O. Roger Anderson
Acta Protozoologica, Volume 61, 2022, pp. 47 - 75
https://doi.org/10.4467/16890027AP.22.003.16206The application of molecular phylogenetics to research on protists has substantially transformed our understanding of their evolution and systematics. More recently, advances in molecular technology, including high throughput sequencing, has opened new avenues for genomic analyses that elucidate major aspects of protistan biology across all levels of biological organization from cellular to ecosystems. This is a review of recent advances (particularly in the last two decades) of transcriptomic research on heterotrophic and autotrophic protists within three major topics: (i) Physiology and metabolism, (ii) Development and life cycles, and (iii) Environmental and ecological studies. Emphasis is placed on selection of representative research that highlights findings across diverse taxonomic groups within each of the three topics. Examples are drawn from parasitic as well as free-living taxa to provide a broad overview of some of the research strategies, and major findings, that have emerged from application of transcriptomics and related techniques in advancing our understanding of protistan biology.
O. Roger Anderson
Acta Protozoologica, Volume 61, 2022, pp. 77 - 83
https://doi.org/10.4467/16890027AP.22.007.16990Marshes bordering rivers and estuaries are productive ecosystems that interact dynamically with the adjacent water mass. This is a multi-year study (2019–2022) of seasonal changes in the density of naked amoebae in monthly samples from the surface water of the Hudson estuary near Piermont, N. Y. with relationships to key environmental variables (surface water temperature, salinity, Secchi depth representing turbidity, and enterococcus bacterial counts). During the colder months (November to March), when decayed leaves and litter from the deciduous marsh grass produced organic matter in the sediment surface, the mean abundance of active amoebae ± standard error of the mean (SEM) was higher (3.07 ± 0.99 × 10⁴/ L, N = 7). In warmer months (May to September) the abundance of amoebae was lower (1.35 ± 0.29 × 10⁴ / L, N = 10). A multivariate linear regression analysis was performed relating amoeba abundance to four major water mass variables, resulting in the following statistically significant equation (p = 0.03): AD = 0.121 × T + 0.301 × L – 0.047 × S + 0.359 × C, where: AD = active amoebae density (× 10 /L), T = temperature ( C), L = tide level (m), S = Secchi disc depth (cm) and C = bacterial enterococcus concentration (number/ml). In general, given the increasing evidence of the potential importance of amoeboid protists in aquatic ecosystems, further research is warranted on their role in food webs and the carbon biogeochemical cycle within heterotrophic estuarine and coastal waters.
Esra Elif Aydin, Won Je Lee
Acta Protozoologica, Volume 61, 2022, pp. 85 - 98
https://doi.org/10.4467/16890027AP.22.008.17111This study was carried out in two hypersaline lakes (Acı and Meke Lakes) in Turkey to understand the diversity and geographic distribution of free-living heterotrophic flagellates. Heterotrophic flagellates of hypersaline environments have not previously been studied in Turkey. We found seventeen morphospecies of heterotrophic flagellates with one unidentified protist. The observed species belong to Craspedida, Heterolobosea, Apusomonadida, Neobodonida, Bicosoecida and Protista incertae sedis. Of the 17 species, ten species were new records for Turkey. All of the morphospecies described here except one unidentified protist were previously reported elsewhere and appear to be cosmopolitan.
Yasmin de Góes Cohn Freitas, Beatriz Rodrigues D’Oliveira Ramos, Viviane Bernardes dos Santos Miranda, Yemna Gomes da Silva, Gabriela Silva Sampaio, Letícia da Silva Nascimento, Christina Wyss Castelo Branco
Acta Protozoologica, Volume 61, 2022, pp. 1 - 21
https://doi.org/10.4467/16890027AP.22.001.15671Testate amoebae (TA) are unicellular protozoans enclosed in a test capable of indicating a wide variety of environmental conditions. Among others, characteristics such as short life cycle, great sensitivity and worldwide distribution makes them adequate bioindicators. As a complement to physical and chemical measurements, biomonitoring can be a cheaper and fastest way of environmental monitoring. This research sought to evaluate the extent of TA use in biomonitoring and the responses given by them to environmental features. The research was conducted in Scielo, Science Direct, Online Library, Google Scholar and Capes Journal Portal and yielded 211 papers. TA bioindication is able to provide information on metal, trace element and atmospheric pollution, and to point out different trophic states, pH, and evidence on characteristics of hydrology. Further, TA can be used in paleoenvironmental reconstruction as they reflect climate, volcanic and even sea level change phenomena. Sometimes, together with other organisms in environmental analysis, they have shown to be an important complement to biomonitoring. Additionally, a functional traits approach has been recently included as a promising tool. Methodological adjustments that have been conducted throughout the years are allowing TA use to be more reliable and precise. This review provides insight on the many possible functions of TA in bioindication studies, highlighting their wide use as bioindicators.
Eman S. El-Wakil, Eman Ali Mohamed, Eman Ahmed El-Wakil, Tarek S. AbouShousha, Neimat Mousa Amer
Acta Protozoologica, Volume 61, 2022, pp. 23 - 34
https://doi.org/10.4467/16890027AP.22.002.16205Cryptosporidium parvum, an Apicomplexan parasite, is an important cause of diarrheal disease, especially in immunodeficient hosts. Nevertheless, there is no entirely successful therapeutic agent against cryptosporidiosis to date. Hence, this study aims to test the potential prophylactic and therapeutic effect of Camellia sinensis (green tea extract) in dexamethasone immunosuppressed mice versus the nowadays used drug, Nitazoxanide (NTZ). Parasitological and molecular methods were used to characterize Cryptosporidium oocysts before infection. Fifty bred female Swiss Albino mice were divided into 5 groups; group I (GI)(GTP): immunosuppressed and prophylactically treated with green tea extract for 5 days prior to infection, group II (GII)(GTT): immunosuppressed, infected with Cryptosporidium parvum and treated with green tea extract, group III (GIII)(NT): immunosuppressed, infected and treated with NTZ, group IV (GIV)(PC): immunosuppressed and infected (Positive control), group V (GV)(NC): immunosuppressed and non-infected (Negative control). Furthermore, parasitological examination for oocysts in the stool, and histopathological examination for the small intestine and liver specimens were performed for the study groups. Cryptosporidium oocysts used for induction of infection proved to be Cryptosporidium parvum genotype 2. Moreover, a significant oocyst reduction in fecal samples correlated with an improvement of histopathological changes in the small intestinal and liver tissues in GI(GTP), GII (GTT) and GIII(NT) groups. Besides, the GII(GTT) group showed the best improvement in parasitological and histopathological parameters among the test groups. This study revealed that Camellia sinensis (green tea extract) has potential activity against cryptosporidiosis and could serve as a promising prophylactic and therapeutic anti-cryptosporidial agent.
Ľubomír Rajter, Borong Lu, Erika Rassoshanska, Micah Dunthorn
Acta Protozoologica, Volume 61, 2022, pp. 35 - 46
https://doi.org/10.4467/16890027AP.22.005.16236Ciliates have a long history of being central in evolutionary and ecological studies on eukaryotic microorganisms. Although thousands of species have been discovered, their total diversity still remains unknown. Here, we will discuss two unsolved problems that hinder the further exploration of ciliate diversity at the species level, and potential solutions to these problems are proposed. First, ciliate morphospecies are difficult to identify because the different silver stains are not scalable (they do not represent high-throughput methods) and basic supplies are lacking (e.g., protargol); a solution may be the development of fluorescent staining techniques. Second, ciliate phylogenetic species are difficult to identify because of extensive paralogy in nuclear-protein-coding genes; a solution may be to concentrate on sequencing mitochondrial genomes. These two approaches could be integrated into a high-throughput fluorescent-single-cell sorting and mitochondrial genomes sequencing process that would enable the observation and better understanding of ciliate species on a massive scale.
O. Roger Anderson
Acta Protozoologica, Volume 61, 2022, pp. 47 - 75
https://doi.org/10.4467/16890027AP.22.003.16206The application of molecular phylogenetics to research on protists has substantially transformed our understanding of their evolution and systematics. More recently, advances in molecular technology, including high throughput sequencing, has opened new avenues for genomic analyses that elucidate major aspects of protistan biology across all levels of biological organization from cellular to ecosystems. This is a review of recent advances (particularly in the last two decades) of transcriptomic research on heterotrophic and autotrophic protists within three major topics: (i) Physiology and metabolism, (ii) Development and life cycles, and (iii) Environmental and ecological studies. Emphasis is placed on selection of representative research that highlights findings across diverse taxonomic groups within each of the three topics. Examples are drawn from parasitic as well as free-living taxa to provide a broad overview of some of the research strategies, and major findings, that have emerged from application of transcriptomics and related techniques in advancing our understanding of protistan biology.
O. Roger Anderson
Acta Protozoologica, Volume 61, 2022, pp. 77 - 83
https://doi.org/10.4467/16890027AP.22.007.16990Marshes bordering rivers and estuaries are productive ecosystems that interact dynamically with the adjacent water mass. This is a multi-year study (2019–2022) of seasonal changes in the density of naked amoebae in monthly samples from the surface water of the Hudson estuary near Piermont, N. Y. with relationships to key environmental variables (surface water temperature, salinity, Secchi depth representing turbidity, and enterococcus bacterial counts). During the colder months (November to March), when decayed leaves and litter from the deciduous marsh grass produced organic matter in the sediment surface, the mean abundance of active amoebae ± standard error of the mean (SEM) was higher (3.07 ± 0.99 × 10⁴/ L, N = 7). In warmer months (May to September) the abundance of amoebae was lower (1.35 ± 0.29 × 10⁴ / L, N = 10). A multivariate linear regression analysis was performed relating amoeba abundance to four major water mass variables, resulting in the following statistically significant equation (p = 0.03): AD = 0.121 × T + 0.301 × L – 0.047 × S + 0.359 × C, where: AD = active amoebae density (× 10 /L), T = temperature ( C), L = tide level (m), S = Secchi disc depth (cm) and C = bacterial enterococcus concentration (number/ml). In general, given the increasing evidence of the potential importance of amoeboid protists in aquatic ecosystems, further research is warranted on their role in food webs and the carbon biogeochemical cycle within heterotrophic estuarine and coastal waters.
Esra Elif Aydin, Won Je Lee
Acta Protozoologica, Volume 61, 2022, pp. 85 - 98
https://doi.org/10.4467/16890027AP.22.008.17111This study was carried out in two hypersaline lakes (Acı and Meke Lakes) in Turkey to understand the diversity and geographic distribution of free-living heterotrophic flagellates. Heterotrophic flagellates of hypersaline environments have not previously been studied in Turkey. We found seventeen morphospecies of heterotrophic flagellates with one unidentified protist. The observed species belong to Craspedida, Heterolobosea, Apusomonadida, Neobodonida, Bicosoecida and Protista incertae sedis. Of the 17 species, ten species were new records for Turkey. All of the morphospecies described here except one unidentified protist were previously reported elsewhere and appear to be cosmopolitan.
Publication date: 2021
Editor-in-Chief: Krzysztof Wiąckowski
John R. Dolan, Jong-Kuk Moon, Eun Jin Yang
Acta Protozoologica, Volume 60, 2021, pp. 1 - 11
https://doi.org/10.4467/16890027AP.21.001.14061Here we summarize the results from 10 cruises in the Chukchi Sea, in August, each year from 2011 to 2020. Samples for the qualitative analysis of the microzooplankton were obtained from stations located across the Chukchi Sea using a 20μm plankton net. Conditions encountered, in terms of sea ice coverage and chlorophyll concentrations, varied widely from year to year without any obvious relationship with the composition of the microzooplankton assemblage. Examining a total of 242 samples gathered, we found a total of 44 tintinnid species (morphologically distinct forms). Plotting cumulative number of tintinnid species encountered vs cumulative number of samplings gave a typical species accumulation curve showing no sign of saturation suggesting that continued sampling in the Chukchi Sea will likely yield increases in the tintinnid species catalogue. The tintinnid species found ranged widely in lorica opening diameters (LOD) from about 11 μm to 80 μm in diameter. However, the median size of the LOD of the tintinnid assemblages varied little from year to year ranging only from about 30 μm to 40 μm. Most of the forms encountered were found in samples from only 1 or 2 cruises. Very few forms were found every year throughout the 10 years of sampling. These were 5 species of tintinnids (Acanthostomella norvegica, Leprotintinnus pellucidus, Pytchocylis obtusa, Salpingella acuminata, Salpingella faurei) and the nasselarian radiolarian Amphimelissa setosa. Examples of the morphological variability observed among individuals of Acanthostomella norvegica and Pytchocylis obtusa within single samples are shown with some individuals easily confused with forms described as other species are shown. To our knowledge, our data are the most extensive data set on Chukchi Sea microplankton. We provide all of the data recorded, which may serve as a baseline from which to assess changes projected in Arctic Sea systems, in a supplementary data file.
Piotr Solarczyk
Acta Protozoologica, Volume 60, 2021, pp. 13 - 20
https://doi.org/10.4467/16890027AP.21.002.14062Cyclospora is an intracellular, gastrointestinal parasite found in birds and mammals worldwide. Limited accessibility of the protozoan for experimental use, scarcity, genome heterogeneity of the isolates and narrow panel of molecular markers hamper zoonotic investigations. One of the significant limitation in zoonotic studies is the lack of precise molecular tools that would be useful in linking animal vectors as a source of human infection. Strong and convincing evidence of zoonotic features will be achieved through proper typing of Cyclospora spp. taxonomic units (e.g. species or genotypes) in animal reservoirs. The most promising method that can be employ for zoonotic surveys is next-generation sequencing.
Kaio Cesar Simiano Tavares, Maria Gabriela Casagrande Dambrós, André Saraiva Leão Antunes, Pietro Martin Danziato, Patricia Hermes Stoco, Aline Daiane Schlindwein, Renato Simões Moreira, Luiz Claudio Miletti
Acta Protozoologica, Volume 60, 2021, pp. 21 - 29
https://doi.org/10.4467/16890027AP.21.003.14063Selenoproteins have been described in all three domains of life and their function has been mainly associated with oxidative stress defense. Canonical elements required for selenoprotein production have been identified in members of the kinetoplastid group supporting the existence of a complete selenocysteine synthesis pathway in these organisms. Currently, nothing is known regarding the selenocysteine pathway in Trypanosoma evansi. In this study, we identified the expression of the elements selB, selC, selD, PSTK and selTRYP at the mRNA level in T. evansi. All translated proteins (selD, PSTK, selTRYP and selB) have the domains predicted and higher identity with Trypanosoma brucei. gambiense. The selenophosphate synthetase protein was localized in the cytoplasm. Our results support the existence of an active selenocysteine pathway in T. evansi.
Tuğba Sağlam, Mustafa Yaman, Ömer Ertürk
Acta Protozoologica, Volume 60, 2021, pp. 31 - 36
https://doi.org/10.4467/16890027AP.21.004.14064The Indian meal moth, Plodia interpunctella (Lepidoptera: Pyralidae) is one of the most important stored product pests. Fumigation plays a significant role in the management of insect pests in stored-products. However, the use of fumigants is problematic because of their effects on the environment and high costs. Entomopathogenic organisms are environmentally friendly control agents and suppress pest populations under natural conditions. In this study, distribution and occurrence of a microsporidian pathogen, Vairimorpha plodiae (Opisthokonta: Microspora) in the populations of P. interpunctella from 12 localities representing Turkey between 2019 and 2020 are presented for the first time by confirming its effectiveness on natural populations. The presence of the microsporidian pathogen was found in 11 of 12 (91.7%) populations. In total, 863 of 3,044 samples were infected by the pathogen. Infection mean was 28.4% for all populations. Our results showed that V. plodiae infection reached to a considerably high prevalence (88.77%) in P. interpunctella populations and varied from 5.1 to 88.7% between the populations. In addition, microsporidia infections have been identified throughout Turkey. We found that V. plodiae can infect all life stages of P. interpunctella. Totally, 623 (28.5%) of 2187 larvae, 14 (37.8%) of 37 pupae, 226 (27%) of 820 adults were found to be infected by the pathogen. There were considerable differences between the dead and living larvae. The microsporidian infection was found in 26 (11.6%) of 225 living larvae, whereas it was found in 595 (30.5%) of 1,952 dead larvae. These results confirm that the microsporidia pathogen has a high spreading potential in P. interpunctella populations and can be a natural biological suppression factor on pest populations.
Abida Akbar , Abdul Hameed, Abdulaziz S. Alouffi, Mashal M. Almutairi, Tania Tanveer, Abdul Matin
Acta Protozoologica, Volume 60, 2021, pp. 37 - 45
https://doi.org/10.4467/16890027AP.21.005.15379Naegleria belongs to the free-living amoeba family and is well-known as a human pathogen. It is recognized as etiological agent of primary amoebic meningoencephalitis involving central nervous system which always leads to death. To date, there is not a single report demonstrating Naegleria isolation and identification from environmental sources of Rawlakot, Azad Jammu and Kashmir Pakistan, and thus the aim of this study. Naegleria was isolated on non-nutrient agar plates seeded with heat killed E. coli and confirmed by morphological properties of the both stages of cyst or trophozoites. Furthermore, PCR was conducted along with direct sequencing of the PCR product for molecular identification. PCR and sequencing data verified the amplification of Naegleria sp. (07) and Vahlkampfia sp. (01) from both water and soil samples. Interestingly two species were successfully isolated and cultured on both 30 and 45°C. To the best of our knowledge this is the first report demonstrating the Naegleria isolation and molecular characterization from environmental sources of Rawlakot, Azad Jammu and Kashmir, Pakistan. The author is anxious for further evaluation of the pathogenic potential of the identified species and explores drinking water across Pakistan to investigate its quality and frequency of FLA, which might be a possible human hazard in future.
Fernando Gómez, Huan Zhang, Leonilde Roselli, Senjie Lin
Acta Protozoologica, Volume 60, 2021, pp. 47 - 59
https://doi.org/10.4467/16890027AP.21.006.15380A dinoflagellate identified as Prorocentrum dentatum, P. shikokuense or P. donghaiense is responsible of massive harmful events. Blooms of a species identified as P. shikokuense have been recently reported in the Mediterranean Sea, and an exotic origin, tentatively introduced by ballast waters from Asia, has been hypothesized. The molecular data based on the small-, large subunit, and internal transcriber spacers ribosomal RNA gene (SSU-, LSU-, ITS rRNA) sequences confirmed P. shikokuense in the Mediterranean Sea. The Mediterranean ribotype is identical to a subtropical North Atlantic ribotype, and with slight divergence from the numerous sequences from the Pacific Ocean. To revisit the relationship between P. shikokuense (=P. donghaiense) and P. obtusidens, we provide the first micrographs of P. dentatum and P. obtusidens, the latter collected from the type locality. Our observations indicate that P. dentatum, P. obtusidens, and P. shikokuense are three different species. Their diagnostic morphological characters are: Prorocentrum dentatum is 44–60 μm long, leaf-shaped, pointed and central posterior end, conspicuous anterior shoulder; P. obtusidens is 33–41 μm long, irregular parallelepiped, almost paralel valve margins, eccentric and pointed posterior end, moderate anterior shoulder; and P. shikokuense is 25 μm long, sunflower seed-shaped, round and centric posterior end, inconspicuous anterior shoulder.
Anatoly Bobrov, Clément Duckert, Edward A. D. Mitchell
Acta Protozoologica, Volume 60, 2021, pp. 61 - 75
https://doi.org/10.4467/16890027AP.21.007.15381Microbial diversity is known to be huge but remains only partly documented. Testate amoebae are a relatively well studied group or free-living protists that build morphologically characteristic shells on which the taxonomy of this group is mainly based. Among testate amoebae, the Hyalospheniformes are especially well documented and are a model group for microbial biogeography. Here we describe a new species of genus Certesella from Sphagnum mosses and forest litter samples collected in the Dominican Republic and Chile. We name this species Certesella larai to honour our esteemed colleague Enrique Lara. This species bears two large pores connected by tube, which are characteristic of the genera Porosia and Certesella. The new species fits best in the latter genus given the presence of a distinct, sometimes denticulated, neck with a bulge that is absent in genus Porosia but occurs in Certesella. Its elongated shape (length/breadth ratio 2.03–2.58) only overlaps with C. certesi, which is distinguishable by the presence of a distinct longitudinal groove in the neck region that is absent from the new species. Interestingly most specimens lacked the internal teeth which are usually present in members of genus Certesella. As such, while the morphology of C. larai strongly suggests a belonging to genus Certesella, molecular analyses are still required to confirm its phylogenetic position, clarify the relationships among all species in genera Porosia and Certesella and the definition and validity of these two genera. The presence of this new species in two rather distant regions – Caribbean and central Chile – suggests it is likely widespread, but possibly rare. However, this perception may be due to a sampling bias in favour of Sphagnum mosses and wet and organic-rich habitats. This illustrates the need for a more systematic sampling effort to document the full and mostly unknown taxonomic diversity of soil protists.
John R. Dolan, Jong-Kuk Moon, Eun Jin Yang
Acta Protozoologica, Volume 60, 2021, pp. 1 - 11
https://doi.org/10.4467/16890027AP.21.001.14061Here we summarize the results from 10 cruises in the Chukchi Sea, in August, each year from 2011 to 2020. Samples for the qualitative analysis of the microzooplankton were obtained from stations located across the Chukchi Sea using a 20μm plankton net. Conditions encountered, in terms of sea ice coverage and chlorophyll concentrations, varied widely from year to year without any obvious relationship with the composition of the microzooplankton assemblage. Examining a total of 242 samples gathered, we found a total of 44 tintinnid species (morphologically distinct forms). Plotting cumulative number of tintinnid species encountered vs cumulative number of samplings gave a typical species accumulation curve showing no sign of saturation suggesting that continued sampling in the Chukchi Sea will likely yield increases in the tintinnid species catalogue. The tintinnid species found ranged widely in lorica opening diameters (LOD) from about 11 μm to 80 μm in diameter. However, the median size of the LOD of the tintinnid assemblages varied little from year to year ranging only from about 30 μm to 40 μm. Most of the forms encountered were found in samples from only 1 or 2 cruises. Very few forms were found every year throughout the 10 years of sampling. These were 5 species of tintinnids (Acanthostomella norvegica, Leprotintinnus pellucidus, Pytchocylis obtusa, Salpingella acuminata, Salpingella faurei) and the nasselarian radiolarian Amphimelissa setosa. Examples of the morphological variability observed among individuals of Acanthostomella norvegica and Pytchocylis obtusa within single samples are shown with some individuals easily confused with forms described as other species are shown. To our knowledge, our data are the most extensive data set on Chukchi Sea microplankton. We provide all of the data recorded, which may serve as a baseline from which to assess changes projected in Arctic Sea systems, in a supplementary data file.
Piotr Solarczyk
Acta Protozoologica, Volume 60, 2021, pp. 13 - 20
https://doi.org/10.4467/16890027AP.21.002.14062Cyclospora is an intracellular, gastrointestinal parasite found in birds and mammals worldwide. Limited accessibility of the protozoan for experimental use, scarcity, genome heterogeneity of the isolates and narrow panel of molecular markers hamper zoonotic investigations. One of the significant limitation in zoonotic studies is the lack of precise molecular tools that would be useful in linking animal vectors as a source of human infection. Strong and convincing evidence of zoonotic features will be achieved through proper typing of Cyclospora spp. taxonomic units (e.g. species or genotypes) in animal reservoirs. The most promising method that can be employ for zoonotic surveys is next-generation sequencing.
Kaio Cesar Simiano Tavares, Maria Gabriela Casagrande Dambrós, André Saraiva Leão Antunes, Pietro Martin Danziato, Patricia Hermes Stoco, Aline Daiane Schlindwein, Renato Simões Moreira, Luiz Claudio Miletti
Acta Protozoologica, Volume 60, 2021, pp. 21 - 29
https://doi.org/10.4467/16890027AP.21.003.14063Selenoproteins have been described in all three domains of life and their function has been mainly associated with oxidative stress defense. Canonical elements required for selenoprotein production have been identified in members of the kinetoplastid group supporting the existence of a complete selenocysteine synthesis pathway in these organisms. Currently, nothing is known regarding the selenocysteine pathway in Trypanosoma evansi. In this study, we identified the expression of the elements selB, selC, selD, PSTK and selTRYP at the mRNA level in T. evansi. All translated proteins (selD, PSTK, selTRYP and selB) have the domains predicted and higher identity with Trypanosoma brucei. gambiense. The selenophosphate synthetase protein was localized in the cytoplasm. Our results support the existence of an active selenocysteine pathway in T. evansi.
Tuğba Sağlam, Mustafa Yaman, Ömer Ertürk
Acta Protozoologica, Volume 60, 2021, pp. 31 - 36
https://doi.org/10.4467/16890027AP.21.004.14064The Indian meal moth, Plodia interpunctella (Lepidoptera: Pyralidae) is one of the most important stored product pests. Fumigation plays a significant role in the management of insect pests in stored-products. However, the use of fumigants is problematic because of their effects on the environment and high costs. Entomopathogenic organisms are environmentally friendly control agents and suppress pest populations under natural conditions. In this study, distribution and occurrence of a microsporidian pathogen, Vairimorpha plodiae (Opisthokonta: Microspora) in the populations of P. interpunctella from 12 localities representing Turkey between 2019 and 2020 are presented for the first time by confirming its effectiveness on natural populations. The presence of the microsporidian pathogen was found in 11 of 12 (91.7%) populations. In total, 863 of 3,044 samples were infected by the pathogen. Infection mean was 28.4% for all populations. Our results showed that V. plodiae infection reached to a considerably high prevalence (88.77%) in P. interpunctella populations and varied from 5.1 to 88.7% between the populations. In addition, microsporidia infections have been identified throughout Turkey. We found that V. plodiae can infect all life stages of P. interpunctella. Totally, 623 (28.5%) of 2187 larvae, 14 (37.8%) of 37 pupae, 226 (27%) of 820 adults were found to be infected by the pathogen. There were considerable differences between the dead and living larvae. The microsporidian infection was found in 26 (11.6%) of 225 living larvae, whereas it was found in 595 (30.5%) of 1,952 dead larvae. These results confirm that the microsporidia pathogen has a high spreading potential in P. interpunctella populations and can be a natural biological suppression factor on pest populations.
Abida Akbar , Abdul Hameed, Abdulaziz S. Alouffi, Mashal M. Almutairi, Tania Tanveer, Abdul Matin
Acta Protozoologica, Volume 60, 2021, pp. 37 - 45
https://doi.org/10.4467/16890027AP.21.005.15379Naegleria belongs to the free-living amoeba family and is well-known as a human pathogen. It is recognized as etiological agent of primary amoebic meningoencephalitis involving central nervous system which always leads to death. To date, there is not a single report demonstrating Naegleria isolation and identification from environmental sources of Rawlakot, Azad Jammu and Kashmir Pakistan, and thus the aim of this study. Naegleria was isolated on non-nutrient agar plates seeded with heat killed E. coli and confirmed by morphological properties of the both stages of cyst or trophozoites. Furthermore, PCR was conducted along with direct sequencing of the PCR product for molecular identification. PCR and sequencing data verified the amplification of Naegleria sp. (07) and Vahlkampfia sp. (01) from both water and soil samples. Interestingly two species were successfully isolated and cultured on both 30 and 45°C. To the best of our knowledge this is the first report demonstrating the Naegleria isolation and molecular characterization from environmental sources of Rawlakot, Azad Jammu and Kashmir, Pakistan. The author is anxious for further evaluation of the pathogenic potential of the identified species and explores drinking water across Pakistan to investigate its quality and frequency of FLA, which might be a possible human hazard in future.
Fernando Gómez, Huan Zhang, Leonilde Roselli, Senjie Lin
Acta Protozoologica, Volume 60, 2021, pp. 47 - 59
https://doi.org/10.4467/16890027AP.21.006.15380A dinoflagellate identified as Prorocentrum dentatum, P. shikokuense or P. donghaiense is responsible of massive harmful events. Blooms of a species identified as P. shikokuense have been recently reported in the Mediterranean Sea, and an exotic origin, tentatively introduced by ballast waters from Asia, has been hypothesized. The molecular data based on the small-, large subunit, and internal transcriber spacers ribosomal RNA gene (SSU-, LSU-, ITS rRNA) sequences confirmed P. shikokuense in the Mediterranean Sea. The Mediterranean ribotype is identical to a subtropical North Atlantic ribotype, and with slight divergence from the numerous sequences from the Pacific Ocean. To revisit the relationship between P. shikokuense (=P. donghaiense) and P. obtusidens, we provide the first micrographs of P. dentatum and P. obtusidens, the latter collected from the type locality. Our observations indicate that P. dentatum, P. obtusidens, and P. shikokuense are three different species. Their diagnostic morphological characters are: Prorocentrum dentatum is 44–60 μm long, leaf-shaped, pointed and central posterior end, conspicuous anterior shoulder; P. obtusidens is 33–41 μm long, irregular parallelepiped, almost paralel valve margins, eccentric and pointed posterior end, moderate anterior shoulder; and P. shikokuense is 25 μm long, sunflower seed-shaped, round and centric posterior end, inconspicuous anterior shoulder.
Anatoly Bobrov, Clément Duckert, Edward A. D. Mitchell
Acta Protozoologica, Volume 60, 2021, pp. 61 - 75
https://doi.org/10.4467/16890027AP.21.007.15381Microbial diversity is known to be huge but remains only partly documented. Testate amoebae are a relatively well studied group or free-living protists that build morphologically characteristic shells on which the taxonomy of this group is mainly based. Among testate amoebae, the Hyalospheniformes are especially well documented and are a model group for microbial biogeography. Here we describe a new species of genus Certesella from Sphagnum mosses and forest litter samples collected in the Dominican Republic and Chile. We name this species Certesella larai to honour our esteemed colleague Enrique Lara. This species bears two large pores connected by tube, which are characteristic of the genera Porosia and Certesella. The new species fits best in the latter genus given the presence of a distinct, sometimes denticulated, neck with a bulge that is absent in genus Porosia but occurs in Certesella. Its elongated shape (length/breadth ratio 2.03–2.58) only overlaps with C. certesi, which is distinguishable by the presence of a distinct longitudinal groove in the neck region that is absent from the new species. Interestingly most specimens lacked the internal teeth which are usually present in members of genus Certesella. As such, while the morphology of C. larai strongly suggests a belonging to genus Certesella, molecular analyses are still required to confirm its phylogenetic position, clarify the relationships among all species in genera Porosia and Certesella and the definition and validity of these two genera. The presence of this new species in two rather distant regions – Caribbean and central Chile – suggests it is likely widespread, but possibly rare. However, this perception may be due to a sampling bias in favour of Sphagnum mosses and wet and organic-rich habitats. This illustrates the need for a more systematic sampling effort to document the full and mostly unknown taxonomic diversity of soil protists.
Publication date: 31.03.2021
Editor-in-Chief: Krzysztof Wiąckowski
Photo on the cover from: Vďačný P. and Foissner W. (2019) Morphology and Ontogenesis of Hemiholosticha pantanalensis nov. spec. (Ciliophora, Hypotrichia, Psilotrichidae). Acta Protozool. 58: 93-113.
Yoichiro Sogame, Katsuhiko Kojima, Toshikazu Takeshita, Shiho Kikuchi, Yuto Shimada, Rikiya Nakamura, Mikihiko Arikawa, Seiji Miyata, Eiji Kinoshita, Futoshi Suizu, Tatsuomi Matsuoka
Acta Protozoologica, Volume 59, Issue 3-4, 2020, pp. 107 - 120
https://doi.org/10.4467/16890027AP.20.009.13264Assays of protein contained in water-soluble fraction of encysting cells Colpoda cucullus Nag-1 by two-dimensional electrophoresis (2-D PAGE) and mass spectrometry (MS) revealed that the amount of β-tubulin abruptly increased in 2.5–10 h after encystment induction. Judging from the results that total α-tubulin content did not decrease much until 12 h after encystment induction, the result indicates that disassembly of microtubules may occur soon after encystment is induced. Therefore, we tried to visualize dynamics of microtubules. Immunofluorescence microscopy using anti-α-tubulin antibody indicated that disassembly of axonemal microtubules of cilia became within 1.5 h after encystment induction, and resorbed in 3 days. Although the cytoplasmic microtubules failed to be visualized clearly, encystmentdependent globulation of cells was promoted by taxol, an inhibitor of disassembly of microtubules. It is possible that a temporary formation of cytoplasmic microtubules may be involved in cell globulation.
The phosphorylation level of actin (43 kDa) became slightly elevated just after encystment induction. Lepidosomes, the sticky small globes surrounding encysting cells, were vividly stained with Acti-stain 555 phalloidin, suggesting that 43-kDa actin or its homologues may be contained in lepidosomes.
Odysseas A. Archontikis, Jeremy R. Young, Lluïsa Cros
Acta Protozoologica, Volume 59, Issue 3-4, 2020, pp. 121 - 139
https://doi.org/10.4467/16890027AP.20.010.13265The genus Anthosphaera Kamptner emend. Kleijne is one of the most taxonomically confusing modern coccolithophores and its species level taxonomy has long been in a state of flux. Based on the review of imaged specimens from our collections, we attempt to rectify the nomenclatural problems and elucidate the obfuscated taxonomy of the genus. Review of included formally and informally described species shows that they are a distinctive group with shared characters, including ten different morphotypes of probable species level. Two of these, including the type species A. fragaria, have been shown to form life-cycle associations with heterococcoliths of the Syracosphaera molischii type. Hence, all species are transferred to Syracosphaera and the new combinations S. periperforata, S. lafourcadii, and S. origami are proposed. In addition, various informally described morphotypes are now formally described as Syracosphaera molischii var. pertusa, S. periperforata var. cylindrata, S. periperforata var. tridentata, S. rotaconica, and S. elevata.
Tatsuomi Matsuoka, Yoichiro Sogame, Rikiya Nakamura, Yuya Hasegawa, Mikihiko Arikawa, Futoshi Suizu
Acta Protozoologica, Volume 59, Issue 3-4, 2020, pp. 141 - 147
https://doi.org/10.4467/16890027AP.20.011.13266We found that the water-rich (osmolality below 0.052 Osm/l) wet resting cysts of the soil ciliate Colpoda cucullus Nag-1 were tolerant to extremely low temperature (−65℃). When cell fluid obtained from the resting cysts was cooled at −65℃, small particles of ice crystals did not grow into large ice crystals. At −65℃, the cysts shrank due to an outflow of water, because a vapor pressure difference was produced between the cell interior and freezing surrounding medium. The osmolality of these shrunk cells was estimated 0.55 Osm/l, and the freezing point depression of the shrunk cell fluid was estimated to be 1.02℃. Hence, the antifreeze ability of wet cysts at −65℃can not be explained by freezing point depression due to elevation of cytoplasmic osmolality.
The cytoplasm of resting cysts was vividly stained red with periodic acid-Schiff (PAS) and stained purple with toluidine blue. On the other hand, the excystment-induced cysts were not stained with PAS, and exhibited a loss of the antifreeze activity. PAS staining of SDSPAGE gel obtained from encysting Colpoda cells showed that a large amount of PAS-positive macromolecules accumulated as the encystment stage progressed. These results suggest that antifreeze polysaccharides may be involved in the antifreeze activity of C. cucullus Nag-1 dormant forms.
Olga Kornilova, Klara Tsushko, Ludmila Chistyakova
Acta Protozoologica, Volume 59, Issue 3-4, 2020, pp. 149 - 155
https://doi.org/10.4467/16890027AP.20.012.13267This paper is a first report on species of endosymbiotic ciliates (Litostomatea, Trichostomatia) inhabiting the intestine of zebras in South Africa. Ciliates from Mountain Zebra were investigated for the first time in the world. The wild population of mountain zebras in general and the Cape Mountain Zebra subspecies in particular is low in numbers: this species is included as vulnerable in the IUCN Red List. Approximately 15 species of trichostome ciliates from 9 different genera were found in the samples collected from wild zebras in Western Cape, South Africa. Some of the ciliate species are also common to horses and other equids, while others are unique for zebras. The ciliates of Triplumaria genus common to elephants and rhinoceroses, and the species Blepharosphaera ceratotherii previously described in rhinoceroses were found in equids for the first time.
Yoichiro Sogame, Katsuhiko Kojima, Toshikazu Takeshita, Shiho Kikuchi, Yuto Shimada, Rikiya Nakamura, Mikihiko Arikawa, Seiji Miyata, Eiji Kinoshita, Futoshi Suizu, Tatsuomi Matsuoka
Acta Protozoologica, Volume 59, Issue 3-4, 2020, pp. 107 - 120
https://doi.org/10.4467/16890027AP.20.009.13264Assays of protein contained in water-soluble fraction of encysting cells Colpoda cucullus Nag-1 by two-dimensional electrophoresis (2-D PAGE) and mass spectrometry (MS) revealed that the amount of β-tubulin abruptly increased in 2.5–10 h after encystment induction. Judging from the results that total α-tubulin content did not decrease much until 12 h after encystment induction, the result indicates that disassembly of microtubules may occur soon after encystment is induced. Therefore, we tried to visualize dynamics of microtubules. Immunofluorescence microscopy using anti-α-tubulin antibody indicated that disassembly of axonemal microtubules of cilia became within 1.5 h after encystment induction, and resorbed in 3 days. Although the cytoplasmic microtubules failed to be visualized clearly, encystmentdependent globulation of cells was promoted by taxol, an inhibitor of disassembly of microtubules. It is possible that a temporary formation of cytoplasmic microtubules may be involved in cell globulation.
The phosphorylation level of actin (43 kDa) became slightly elevated just after encystment induction. Lepidosomes, the sticky small globes surrounding encysting cells, were vividly stained with Acti-stain 555 phalloidin, suggesting that 43-kDa actin or its homologues may be contained in lepidosomes.
Odysseas A. Archontikis, Jeremy R. Young, Lluïsa Cros
Acta Protozoologica, Volume 59, Issue 3-4, 2020, pp. 121 - 139
https://doi.org/10.4467/16890027AP.20.010.13265The genus Anthosphaera Kamptner emend. Kleijne is one of the most taxonomically confusing modern coccolithophores and its species level taxonomy has long been in a state of flux. Based on the review of imaged specimens from our collections, we attempt to rectify the nomenclatural problems and elucidate the obfuscated taxonomy of the genus. Review of included formally and informally described species shows that they are a distinctive group with shared characters, including ten different morphotypes of probable species level. Two of these, including the type species A. fragaria, have been shown to form life-cycle associations with heterococcoliths of the Syracosphaera molischii type. Hence, all species are transferred to Syracosphaera and the new combinations S. periperforata, S. lafourcadii, and S. origami are proposed. In addition, various informally described morphotypes are now formally described as Syracosphaera molischii var. pertusa, S. periperforata var. cylindrata, S. periperforata var. tridentata, S. rotaconica, and S. elevata.
Tatsuomi Matsuoka, Yoichiro Sogame, Rikiya Nakamura, Yuya Hasegawa, Mikihiko Arikawa, Futoshi Suizu
Acta Protozoologica, Volume 59, Issue 3-4, 2020, pp. 141 - 147
https://doi.org/10.4467/16890027AP.20.011.13266We found that the water-rich (osmolality below 0.052 Osm/l) wet resting cysts of the soil ciliate Colpoda cucullus Nag-1 were tolerant to extremely low temperature (−65℃). When cell fluid obtained from the resting cysts was cooled at −65℃, small particles of ice crystals did not grow into large ice crystals. At −65℃, the cysts shrank due to an outflow of water, because a vapor pressure difference was produced between the cell interior and freezing surrounding medium. The osmolality of these shrunk cells was estimated 0.55 Osm/l, and the freezing point depression of the shrunk cell fluid was estimated to be 1.02℃. Hence, the antifreeze ability of wet cysts at −65℃can not be explained by freezing point depression due to elevation of cytoplasmic osmolality.
The cytoplasm of resting cysts was vividly stained red with periodic acid-Schiff (PAS) and stained purple with toluidine blue. On the other hand, the excystment-induced cysts were not stained with PAS, and exhibited a loss of the antifreeze activity. PAS staining of SDSPAGE gel obtained from encysting Colpoda cells showed that a large amount of PAS-positive macromolecules accumulated as the encystment stage progressed. These results suggest that antifreeze polysaccharides may be involved in the antifreeze activity of C. cucullus Nag-1 dormant forms.
Olga Kornilova, Klara Tsushko, Ludmila Chistyakova
Acta Protozoologica, Volume 59, Issue 3-4, 2020, pp. 149 - 155
https://doi.org/10.4467/16890027AP.20.012.13267This paper is a first report on species of endosymbiotic ciliates (Litostomatea, Trichostomatia) inhabiting the intestine of zebras in South Africa. Ciliates from Mountain Zebra were investigated for the first time in the world. The wild population of mountain zebras in general and the Cape Mountain Zebra subspecies in particular is low in numbers: this species is included as vulnerable in the IUCN Red List. Approximately 15 species of trichostome ciliates from 9 different genera were found in the samples collected from wild zebras in Western Cape, South Africa. Some of the ciliate species are also common to horses and other equids, while others are unique for zebras. The ciliates of Triplumaria genus common to elephants and rhinoceroses, and the species Blepharosphaera ceratotherii previously described in rhinoceroses were found in equids for the first time.
Publication date: 2020
Editor-in-Chief: Krzysztof Wiąckowski
Photo on the cover from: Vďačný P. and Foissner W. (2019) Morphology and Ontogenesis of Hemiholosticha pantanalensis nov. spec. (Ciliophora, Hypotrichia, Psilotrichidae). Acta Protozool. 58: 93-113.
Franciane Cedrola, Marta D'agosto, Isabel Martinele, Roberto Júnio Pedroso Dias
Acta Protozoologica, Volume 59, Issue 2, 2020, pp. 61 - 65
https://doi.org/10.4467/16890027AP.20.005.12673The present study redescribes the species Polyplastron alaskum based on morphological characterization and provides, for the first time, data on its infraciliary bands pattern. Polyplastron alaskum was described in Alaskan dall montain sheep (Ovis dalli), and registered again only in the present study, 45 years later, inhabiting the rumen contents of domestic sheep (Ovis aries) in northeastern Brazil. All the taxonomic characters observed in the original description was observed in the present study. The infraciliary pattern in Polyplastron alaskum is slightly different of Diplodinium-type, observed in some ophryoscolecids belonging to the subfamily Diplodiniinae.
Ryota Saito, Ryota Koizumi, Tatsuya Sakai, Taiga Shimizu, Taiki Ono, Yoichiro Sogame
Acta Protozoologica, Volume 59, Issue 2, 2020, pp. 67 - 75
https://doi.org/10.4467/16890027AP.20.006.12674The ciliate Colpoda cucullus forms resting cysts to survive unfavorable environmental stresses. In this study, we have shown that Colpoda resting cysts survived exposure to a gamma radiation dose of 4000 Gy, although vegetative cells were killed by 500 Gy. After 4000 Gy irradiation, more than 90% of resting cysts and approximately 70% of dry cysts could excyst to form vegetative cells. In both cases, the excystment gradually increased after the induction of excystment. In addition, we also showed that protein carbonylation level was increased by gamma irradiation, but decreased by incubation in the cyst state. These results indicated that cell damage was repaired in resting cysts. Colpoda probably developed tolerance to gamma radiation by forming resting cysts as a strategy for growth in terrestrial environments, as part of contending with the stress due to reactive oxygen species caused by desiccation.
Fernando Gómez, Luis F. Artigas, Rebecca J. Gast
Acta Protozoologica, Volume 59, Issue 2, 2020, pp. 77 - 87
https://doi.org/10.4467/16890027AP.20.007.12675The North Sea and the English Channel are regions with a long tradition of plankton studies, where the colony-forming haptophyte Phaeocystis globosa dominates the spring phytoplankton blooms. Among its predators, we investigated an abundant unarmored dinoflagellate (~3000 cells per liter) in the North Sea in May 2019. It has been reported in the literature as Gymnodinium heterostriatum or G. striatissimum, and often identified as Gyrodinium spirale. Phylogenetic analyses using the small-, large subunit- and Internal Transcriber Spacers of the ribosomal RNA (SSU-, LSU-, ITS rRNA) gene sequences indicate that our isolates clustered within the Gyrodinium clade. The new sequences formed a sister group with sequences of the freshwater taxon Gyrodinium helveticum, being one of the infrequent marine-freshwater transitions in the microbial world. This isolate is the first characterized member of a clade of numerous environmental sequences widely distributed from cold to tropical seas. This common and abundant taxon has received several names due to its morphological plasticity (changes of size and shape, often deformed after engulfing prey) and the difficulty in discerning surface striation. We conclude that the priority is for the species name Gymnodinium heterostriatum Kofoid & Swezy 1921, a new name that was proposed for Gymnodinium spirale var. obtusum sensu Dogiel 1906. The species Gyrodinium striatissimum (Hulburt 1957) Gert Hansen & Moestrup 2000 and Gymnodinium lucidum D. Ballantine in Parke & Dixon 1964 (=G. hyalinum M. Lebour 1925) are posterior synonyms. We propose Gyrodinium heterostriatum comb. nov. for Gymnodinium heterostriatum.
Yoshiyuki Aoki, Yoichiro Sogame, Manfred Wanner, Yuri Mazei, Satoshi D. Shimano
Acta Protozoologica, Volume 59, Issue 2, 2020, pp. 99 - 105
https://doi.org/10.4467/16890027AP.20.008.12676A new species of a testate amoeba, Matsakision ogawaraensis sp. nov., is described from Ogawara pond, Aomori Prefecture, Japan. This is the third species in the genus Matsakision. Matsakision ogawaraensis sp. nov. is distinguished from two other species by the specific form of the shell in apertural view, which is triangular (the shells of other species are circular or elliptic). In addition, it has a chitinous lip around the aperture. For the first time, long needle-like pseudopodia have been observed.
Franciane Cedrola, Marta D'agosto, Isabel Martinele, Roberto Júnio Pedroso Dias
Acta Protozoologica, Volume 59, Issue 2, 2020, pp. 61 - 65
https://doi.org/10.4467/16890027AP.20.005.12673The present study redescribes the species Polyplastron alaskum based on morphological characterization and provides, for the first time, data on its infraciliary bands pattern. Polyplastron alaskum was described in Alaskan dall montain sheep (Ovis dalli), and registered again only in the present study, 45 years later, inhabiting the rumen contents of domestic sheep (Ovis aries) in northeastern Brazil. All the taxonomic characters observed in the original description was observed in the present study. The infraciliary pattern in Polyplastron alaskum is slightly different of Diplodinium-type, observed in some ophryoscolecids belonging to the subfamily Diplodiniinae.
Ryota Saito, Ryota Koizumi, Tatsuya Sakai, Taiga Shimizu, Taiki Ono, Yoichiro Sogame
Acta Protozoologica, Volume 59, Issue 2, 2020, pp. 67 - 75
https://doi.org/10.4467/16890027AP.20.006.12674The ciliate Colpoda cucullus forms resting cysts to survive unfavorable environmental stresses. In this study, we have shown that Colpoda resting cysts survived exposure to a gamma radiation dose of 4000 Gy, although vegetative cells were killed by 500 Gy. After 4000 Gy irradiation, more than 90% of resting cysts and approximately 70% of dry cysts could excyst to form vegetative cells. In both cases, the excystment gradually increased after the induction of excystment. In addition, we also showed that protein carbonylation level was increased by gamma irradiation, but decreased by incubation in the cyst state. These results indicated that cell damage was repaired in resting cysts. Colpoda probably developed tolerance to gamma radiation by forming resting cysts as a strategy for growth in terrestrial environments, as part of contending with the stress due to reactive oxygen species caused by desiccation.
Fernando Gómez, Luis F. Artigas, Rebecca J. Gast
Acta Protozoologica, Volume 59, Issue 2, 2020, pp. 77 - 87
https://doi.org/10.4467/16890027AP.20.007.12675The North Sea and the English Channel are regions with a long tradition of plankton studies, where the colony-forming haptophyte Phaeocystis globosa dominates the spring phytoplankton blooms. Among its predators, we investigated an abundant unarmored dinoflagellate (~3000 cells per liter) in the North Sea in May 2019. It has been reported in the literature as Gymnodinium heterostriatum or G. striatissimum, and often identified as Gyrodinium spirale. Phylogenetic analyses using the small-, large subunit- and Internal Transcriber Spacers of the ribosomal RNA (SSU-, LSU-, ITS rRNA) gene sequences indicate that our isolates clustered within the Gyrodinium clade. The new sequences formed a sister group with sequences of the freshwater taxon Gyrodinium helveticum, being one of the infrequent marine-freshwater transitions in the microbial world. This isolate is the first characterized member of a clade of numerous environmental sequences widely distributed from cold to tropical seas. This common and abundant taxon has received several names due to its morphological plasticity (changes of size and shape, often deformed after engulfing prey) and the difficulty in discerning surface striation. We conclude that the priority is for the species name Gymnodinium heterostriatum Kofoid & Swezy 1921, a new name that was proposed for Gymnodinium spirale var. obtusum sensu Dogiel 1906. The species Gyrodinium striatissimum (Hulburt 1957) Gert Hansen & Moestrup 2000 and Gymnodinium lucidum D. Ballantine in Parke & Dixon 1964 (=G. hyalinum M. Lebour 1925) are posterior synonyms. We propose Gyrodinium heterostriatum comb. nov. for Gymnodinium heterostriatum.
Yoshiyuki Aoki, Yoichiro Sogame, Manfred Wanner, Yuri Mazei, Satoshi D. Shimano
Acta Protozoologica, Volume 59, Issue 2, 2020, pp. 99 - 105
https://doi.org/10.4467/16890027AP.20.008.12676A new species of a testate amoeba, Matsakision ogawaraensis sp. nov., is described from Ogawara pond, Aomori Prefecture, Japan. This is the third species in the genus Matsakision. Matsakision ogawaraensis sp. nov. is distinguished from two other species by the specific form of the shell in apertural view, which is triangular (the shells of other species are circular or elliptic). In addition, it has a chitinous lip around the aperture. For the first time, long needle-like pseudopodia have been observed.
Publication date: 03.2020
Editor-in-Chief: Krzysztof Wiąckowski
Photo on the cover from: Vďačný P. and Foissner W. (2019) Morphology and Ontogenesis of Hemiholosticha pantanalensis nov. spec. (Ciliophora, Hypotrichia, Psilotrichidae). Acta Protozool. 58: 93-113.
Risa Ikeda, Miki Kurokawa, Momoka Murai, Noboru Saito, Motonori Ando
Acta Protozoologica, Volume 59, Issue 1, 2020, pp. 1 - 12
https://doi.org/10.4467/16890027AP.20.001.12157The centrohelid Raphidocystis contractilis is a heliozoan that has many radiating axopodia, each containing a bundle of microtubules. Although the rapid contraction of the axopodia at nearly a video rate (30 frames/s) is induced by mechanical stimuli, the mechanism underlying this phenomenon in R. contractilis has not yet been elucidated. In the present study, we described for the first time an adequate immunocytochemical fixation procedure for R. contractilis and the cellular distribution of α-tubulin before and after rapid axopodial contraction. We developed a flow-through chamber equipped with a micro-syringe pump that allowed the test solution to be injected at a flow rate below the threshold required to induce rapid axopodial contraction. Next, we used this injection method for evaluating the effects of different combinations of two fixatives (paraformaldehyde or glutaraldehyde) and two buffers (phosphate buffer or PHEM) on the morphological structure of the axopodia. A low concentration of glutaraldehyde in PHEM was identified as an adequate fixative for immunocytochemistry. The distribution of α-tubulin before and after rapid axopodial contraction was examined using immunocytochemistry and confocal laser scanning fluorescence microscopy. Positive signals were initially detected along the extended axopodia from the tips to the bases and were distributed in a non-uniform manner within the axopodia. Conversely, after the induction of a rapid axopodial contraction, these positive signals accumulated in the peripheral region of the cell. These results indicated that axopodial microtubules disassemble into fragments and/ or tubulin subunits during rapid axopodial contraction. Therefore, we hypothesize that the mechanism of extremely rapid axopodial contraction accompanied by cytoskeletal microtubule degradation in R. contractilis involves microtubule-severing at multiple sites.
Miroslav Macek, Ximena Sánchez Medina, Antonio Picazo, Dana Peštová, Fernando Bautista Reyes, Jorge Ricardo Montiel Hernández, Javier Alcocer, Martín Merino Ibarra, Antonio Camacho
Acta Protozoologica, Volume 59, Issue 1, 2020, pp. 13 - 38
https://doi.org/10.4467/16890027AP.20.002.12158The pelagic / anoxic hypolimnion population of Spirostomum teres was investigated as a part of the long-term ciliates’ monitoring (2003–2016) in an oligo- to mesotrophic monomictic hyposaline crater lake Alchichica (Puebla / Veracruz, Mexico), including an analysis of picoplankton (both heterotrophic, HPP and autotrophic, APP) and inorganic compounds of nitrogen (ammonium, nitrite, nitrate), phosphorus (dissolved reactive phosphorus, DRP) and silicon. Additionally, detailed studies of the ciliate vertical distribution and feeding activity measured upon fluorescently labelled APP (picocyanobacteria) were carried out. The results were compared with those from a neighbour freshwater crater lake La Preciosa and with a meromictic karstic lake La Cruz (Cuenca, Spain). The ciliate vertical distribution within the water column was very well defined: During the first decade, the benthic population was frequently found throughout a developing stratification of the lake. The established stratification of the lake turned the conditions favourable for the formation of an oxycline / hypolimnion population, typically, several meters below the deep chlorophyll maximum (formed basically by diatoms); the population preferred the layers without detectable dissolved oxygen. However, an observed gradient of light (PAR) could support both oxygenic and anoxygenic photosynthesis. Late stratification after deepening of the thermocline reduced the layers with S. teres population to a minimum apparently due to the drastic change in physicochemical conditions within a metalimnion, coupled with an oxycline, and limited to 1 to 2 meters; microstratification was found. Last years, the very bottom population disappeared or it was reduced and the late stratification S. teres peaks were smaller or did not appeared. Generally, S. teres oxycline / anoxic hypolimnion population was observed from June through November. Optimum picoplankton numbers in conditions that supported the ciliate growth were found: The ciliate was peaking at APP of 0.6 to 1 × 105 cells mL–1; the optimum of HPP was observed round 1.4 × 106 cells mL–1. S. teres was efficiently feeding upon picocyanobacteria in numbers of 105 cells mL–1 reaching the clearance rate of 2000 nL cell–1h–1, which represented in average 130 to 210 cells cell–1h–1 ingested. Feeding upon purple sulphur bacteria was observed but only during the end of the lake stable stratification when the ciliate population was already dropping. On the other hand, the volume specific clearance of S. teres upon picocyanobacteria (103 h–1) did not support the hypothesis that they could serve as a sole prey. Feeding upon eukaryote phytoplankton (chlorophytes Monoraphidium minutum, diatoms Cyclotella choc tawhatcheeana) could be of higher importance that previously supposed. Additionally, a use of ingested and retained photosynthetic prokaryotes is hypothesized.
Anupma Garg, Anshu Chaudhary, Abhishek Gupta, Abhinav Kumar, Bindu Sharma, Hridaya Shanker Singh
Acta Protozoologica, Volume 59, Issue 1, 2020, pp. 39 - 53
https://doi.org/10.4467/16890027AP.20.003.12159In Indian freshwater fish myxosporean infections are among the most cosmopolitan parasites, they are relatively well studied morphologically but their phylogenetic relationships were unclear and the genetic data is limited only to a few species. The study aims to present molecular data for two myxosporean species, Henneguya namae Haldar et al. 1983 and Myxobolus sophorae Jayasri, 1982 collected from Indian freshwater fish, the elongate glass-perchlet Chanda nama (=Ambassis nama) and pool barb Puntius sophore, respectively. In the present study molecular data are provided for H. namae and M. sophorae using nested PCR. The obtained partial 18S rDNA gene sequences were analyzed using maximum likelihood (ML) and Bayesian inference (BI) methods. The 18S rDNA gene sequences of H. namae showed similarity with the sequences of H. chaudhuryi, Henneguya sp. RA-2015, H. voronini and H. setiuensis about 72.1 to 78% and M. sophorae with Myxobolus ticto was about 90% respectively. The aim of this paper was to identify H. namae and M. sophorae morphologically and using molecular methods.
Shinji Yamane, Maho Watanabe, Ryoji Funadani, Ryutaro Miyazaki, Yuya Hasegawa, Mikihiko Arikawa, Futoshi Suizu, Kou Matsuoka, Tatsuomi Matsuoka
Acta Protozoologica, Volume 59, Issue 1, 2020, pp. 55 - 60
https://doi.org/10.4467/16890027AP.20.004.12160Resting cysts of the terrestrial ciliate Colpoda cucullus (Nag-1 strain) are highly resistant to UV light. It has been speculated that auto-fluorescent (blue fluorescent) particles surrounding the nuclei and yellowish fluorescent layers of the cyst wall are the candidate structures for the protection of the cellular components from UV light. The UV resistance of encysting cells was quickly acquired up to 5 h after the onset of encystment induction, and then gradually increased for several days. The less fluorescent ectocyst layer, yellowish fluorescent first-synthesized endocyst layer (en-1) and the NSPs were formed within 5 h after the onset of encystment induction, and thereafter endocyst layers became gradually thicker for several days. The cyst wall sample (ectocyst and endocyst layers) markedly absorbed a broad range of UV light. This result indicates that the cyst wall evidently has UV-cut function. These results support that the cyst wall and NSPs of C. cucullus play a role in the shielding of the cell components from UV light.
Risa Ikeda, Miki Kurokawa, Momoka Murai, Noboru Saito, Motonori Ando
Acta Protozoologica, Volume 59, Issue 1, 2020, pp. 1 - 12
https://doi.org/10.4467/16890027AP.20.001.12157The centrohelid Raphidocystis contractilis is a heliozoan that has many radiating axopodia, each containing a bundle of microtubules. Although the rapid contraction of the axopodia at nearly a video rate (30 frames/s) is induced by mechanical stimuli, the mechanism underlying this phenomenon in R. contractilis has not yet been elucidated. In the present study, we described for the first time an adequate immunocytochemical fixation procedure for R. contractilis and the cellular distribution of α-tubulin before and after rapid axopodial contraction. We developed a flow-through chamber equipped with a micro-syringe pump that allowed the test solution to be injected at a flow rate below the threshold required to induce rapid axopodial contraction. Next, we used this injection method for evaluating the effects of different combinations of two fixatives (paraformaldehyde or glutaraldehyde) and two buffers (phosphate buffer or PHEM) on the morphological structure of the axopodia. A low concentration of glutaraldehyde in PHEM was identified as an adequate fixative for immunocytochemistry. The distribution of α-tubulin before and after rapid axopodial contraction was examined using immunocytochemistry and confocal laser scanning fluorescence microscopy. Positive signals were initially detected along the extended axopodia from the tips to the bases and were distributed in a non-uniform manner within the axopodia. Conversely, after the induction of a rapid axopodial contraction, these positive signals accumulated in the peripheral region of the cell. These results indicated that axopodial microtubules disassemble into fragments and/ or tubulin subunits during rapid axopodial contraction. Therefore, we hypothesize that the mechanism of extremely rapid axopodial contraction accompanied by cytoskeletal microtubule degradation in R. contractilis involves microtubule-severing at multiple sites.
Miroslav Macek, Ximena Sánchez Medina, Antonio Picazo, Dana Peštová, Fernando Bautista Reyes, Jorge Ricardo Montiel Hernández, Javier Alcocer, Martín Merino Ibarra, Antonio Camacho
Acta Protozoologica, Volume 59, Issue 1, 2020, pp. 13 - 38
https://doi.org/10.4467/16890027AP.20.002.12158The pelagic / anoxic hypolimnion population of Spirostomum teres was investigated as a part of the long-term ciliates’ monitoring (2003–2016) in an oligo- to mesotrophic monomictic hyposaline crater lake Alchichica (Puebla / Veracruz, Mexico), including an analysis of picoplankton (both heterotrophic, HPP and autotrophic, APP) and inorganic compounds of nitrogen (ammonium, nitrite, nitrate), phosphorus (dissolved reactive phosphorus, DRP) and silicon. Additionally, detailed studies of the ciliate vertical distribution and feeding activity measured upon fluorescently labelled APP (picocyanobacteria) were carried out. The results were compared with those from a neighbour freshwater crater lake La Preciosa and with a meromictic karstic lake La Cruz (Cuenca, Spain). The ciliate vertical distribution within the water column was very well defined: During the first decade, the benthic population was frequently found throughout a developing stratification of the lake. The established stratification of the lake turned the conditions favourable for the formation of an oxycline / hypolimnion population, typically, several meters below the deep chlorophyll maximum (formed basically by diatoms); the population preferred the layers without detectable dissolved oxygen. However, an observed gradient of light (PAR) could support both oxygenic and anoxygenic photosynthesis. Late stratification after deepening of the thermocline reduced the layers with S. teres population to a minimum apparently due to the drastic change in physicochemical conditions within a metalimnion, coupled with an oxycline, and limited to 1 to 2 meters; microstratification was found. Last years, the very bottom population disappeared or it was reduced and the late stratification S. teres peaks were smaller or did not appeared. Generally, S. teres oxycline / anoxic hypolimnion population was observed from June through November. Optimum picoplankton numbers in conditions that supported the ciliate growth were found: The ciliate was peaking at APP of 0.6 to 1 × 105 cells mL–1; the optimum of HPP was observed round 1.4 × 106 cells mL–1. S. teres was efficiently feeding upon picocyanobacteria in numbers of 105 cells mL–1 reaching the clearance rate of 2000 nL cell–1h–1, which represented in average 130 to 210 cells cell–1h–1 ingested. Feeding upon purple sulphur bacteria was observed but only during the end of the lake stable stratification when the ciliate population was already dropping. On the other hand, the volume specific clearance of S. teres upon picocyanobacteria (103 h–1) did not support the hypothesis that they could serve as a sole prey. Feeding upon eukaryote phytoplankton (chlorophytes Monoraphidium minutum, diatoms Cyclotella choc tawhatcheeana) could be of higher importance that previously supposed. Additionally, a use of ingested and retained photosynthetic prokaryotes is hypothesized.
Anupma Garg, Anshu Chaudhary, Abhishek Gupta, Abhinav Kumar, Bindu Sharma, Hridaya Shanker Singh
Acta Protozoologica, Volume 59, Issue 1, 2020, pp. 39 - 53
https://doi.org/10.4467/16890027AP.20.003.12159In Indian freshwater fish myxosporean infections are among the most cosmopolitan parasites, they are relatively well studied morphologically but their phylogenetic relationships were unclear and the genetic data is limited only to a few species. The study aims to present molecular data for two myxosporean species, Henneguya namae Haldar et al. 1983 and Myxobolus sophorae Jayasri, 1982 collected from Indian freshwater fish, the elongate glass-perchlet Chanda nama (=Ambassis nama) and pool barb Puntius sophore, respectively. In the present study molecular data are provided for H. namae and M. sophorae using nested PCR. The obtained partial 18S rDNA gene sequences were analyzed using maximum likelihood (ML) and Bayesian inference (BI) methods. The 18S rDNA gene sequences of H. namae showed similarity with the sequences of H. chaudhuryi, Henneguya sp. RA-2015, H. voronini and H. setiuensis about 72.1 to 78% and M. sophorae with Myxobolus ticto was about 90% respectively. The aim of this paper was to identify H. namae and M. sophorae morphologically and using molecular methods.
Shinji Yamane, Maho Watanabe, Ryoji Funadani, Ryutaro Miyazaki, Yuya Hasegawa, Mikihiko Arikawa, Futoshi Suizu, Kou Matsuoka, Tatsuomi Matsuoka
Acta Protozoologica, Volume 59, Issue 1, 2020, pp. 55 - 60
https://doi.org/10.4467/16890027AP.20.004.12160Resting cysts of the terrestrial ciliate Colpoda cucullus (Nag-1 strain) are highly resistant to UV light. It has been speculated that auto-fluorescent (blue fluorescent) particles surrounding the nuclei and yellowish fluorescent layers of the cyst wall are the candidate structures for the protection of the cellular components from UV light. The UV resistance of encysting cells was quickly acquired up to 5 h after the onset of encystment induction, and then gradually increased for several days. The less fluorescent ectocyst layer, yellowish fluorescent first-synthesized endocyst layer (en-1) and the NSPs were formed within 5 h after the onset of encystment induction, and thereafter endocyst layers became gradually thicker for several days. The cyst wall sample (ectocyst and endocyst layers) markedly absorbed a broad range of UV light. This result indicates that the cyst wall evidently has UV-cut function. These results support that the cyst wall and NSPs of C. cucullus play a role in the shielding of the cell components from UV light.
Publication date: 23.12.2019
Editor-in-Chief: Krzysztof Wiąckowski
Photo on the cover fromr: De Jager G. P., Basson L., Van Marwijk J. (2019) A New Trichodina Species (Peritrichia: Mobilida) from Anuran Tadpole Hosts, Sclerophrys spp. in the Okavango Panhandle, Botswana, with Comments on this Taxon. Acta Protozool. 58: 141-153.
Won Je Lee
Acta Protozoologica, Volume 58, Issue 4, 2019, pp. 167 - 189
https://doi.org/10.4467/16890027AP.19.016.12018A total of 155 species and 75 genera were found at marine sediments in Sydney region (Australia) and are described using light microscopy: 117 species at Port Botany, 111 species at Kogarah Bay, 94 species at Woolooware Bay, 126 species at Quibray Bay, 74 species at Avoca beach, 48 species at Watsons Bay. The records include accounts of 15 unidentified taxa and two new taxa: Eoramonas jungensis sp. nov. (Eoramonas gen. nov.), Protaspa flexibilis sp. nov. Most flagellates described here have been found at other locations worldwide, but many species not reported from any other locations. I am unable to assess if these species are endemic because of the lack of intensive studies elsewhere. However, these results suggest that the flagellate communities from Botany Bay are distinctive.
Jingbao Li, Keqing Wen , Erkang Zhu , Jingyi Wang
Acta Protozoologica, Volume 58, Issue 4, 2019, pp. 191 - 200
https://doi.org/10.4467/16890027AP.19.017.12019A soil urostylid ciliate Extraholosticha sylvatica, isolated from southern China, is studied using live observation and protargol impregnation. The main ontogenetic features of E. sylvatica are as follows: (a) in the proter, only the posterior part of the parental adoral zone of membranelles is renewed, while the anterior portion is retained; undulating membranes anlage undergo, like most hypotrichs, depolymerization of old undulating membranes and differentiation of new structures; (b) the oral primordium in the opisthe and the frontoventraltransverse cirral anlagen in both daughter cells are formed with contribution of the parental midventral cirri; (c) three frontal, one buccal, three to five frontoventral, one or two frontoterminal, two or three pretransverse ventral and six to 11 transverse cirri and 16–22 midventral pairs are generated from frontoventral-transverse cirral anlagen; (d) in both the left and the right marginal rows as well as the dorsal kineties, each two anlagen are formed intrakinetally; three to six caudal cirri are formed at the posterior end of the 5th dorsal kinety anlage; (e) the macronuclear nodules fuse into a single mass during the process.
Najla Baković, Ferry J. Siemensma , Robert Baković, Josip Rubinić
Acta Protozoologica, Volume 58, Issue 4, 2019, pp. 201 - 215
https://doi.org/10.4467/16890027AP.19.018.12020Karst freshwater caves are subterranean habitats characterized by the constant absence of light and relatively small variations of temperature and air humidity. They are mostly food deprived environments, with the exception if large bat colonies are present or if they are intensively supplied with organic matter by sinking rivers. Even though these habitats are often described as harsh, they have enabled the evolution of highly specialized and often endemic animals. The cave eukaryotic micro-organisms, on the other hand, are scarcely researched. The results of research of testate amoebae in the caves of the Dinaric arc detected 23 species, 12 of which were first found in caves. Also, a description of Centropyxis bipilata sp. nov. is presented. This species is clearly distinguished from other described species based on shell size, the presence of two struts and the usually dark ring around the aperture. Testate amoebae were registered on aquatic and terrestrial cave sediments and transitional habitats (like hygropetric and wet walls). The most frequent species within the samples were: Trinema lineare, Cryptodifflugia oviformis and Centropyxis bipilata sp. nov. Maximum diversity of testate amoebae was registered in Ponor Kovači with twenty species. In 24.4 % of the investigated samples microphototrophs were found, implying good surface-subsurface connectivity that could also affect testate amoebae diversity. This research showed that caves are underestimated habitats that can provide us with new data about the testate amoebae biogeography and diversity.
Giulia M. Ribeiro, Paulo Inácio Prado , Renato Mendes Coutinho , Marina Costa Rillo , Samuel Pereira Junior, Alfredo L. Porfírio-Sousa, Daniel J. G. Lahr
Acta Protozoologica, Volume 58, Issue 4, 2019, pp. 217 - 233
https://doi.org/10.4467/16890027AP.19.019.12021Coexistence usually are exceeding the explicable rate by competitive exclusion principle. Since the pioneer Gause, many studies have used protist microcosm systems to study competitive exclusion. We explored a two-species system with the testate-amoebae: (Arcella intermedia and Pyxidicula operculata), where competitive exclusion is expected to occur. We determined their growth curves individually and under competitive interaction. We used a state-space model to represent system dynamics and calculated posterior population sizes simulating competition dynamics. Contrarily to our expectation, Arcella and Pyxidicula showed similar growth rates (1.37 and 1.46 days–1 respectively) and only different carrying capacity (1,997 and 25,108 cells cm–2 respectively). The maximum number of cells of both species when growing in competition was much lower if compared to the monospecific cultures (in average, 73% and 80% less for Arcella and Pyxidicula respectively). However, our competition experiments always resulted in coexistence. According to the models, the drop in growth rates and stochasticity mainly explains our coexistence results. We propose that a context of ephemeral resources can explain these results. Additionally, we propose generating factors of stochasticity as intraspecific variation, small population effects, toxicity of waste products and influence of the bacterial community.
Won Je Lee
Acta Protozoologica, Volume 58, Issue 4, 2019, pp. 167 - 189
https://doi.org/10.4467/16890027AP.19.016.12018A total of 155 species and 75 genera were found at marine sediments in Sydney region (Australia) and are described using light microscopy: 117 species at Port Botany, 111 species at Kogarah Bay, 94 species at Woolooware Bay, 126 species at Quibray Bay, 74 species at Avoca beach, 48 species at Watsons Bay. The records include accounts of 15 unidentified taxa and two new taxa: Eoramonas jungensis sp. nov. (Eoramonas gen. nov.), Protaspa flexibilis sp. nov. Most flagellates described here have been found at other locations worldwide, but many species not reported from any other locations. I am unable to assess if these species are endemic because of the lack of intensive studies elsewhere. However, these results suggest that the flagellate communities from Botany Bay are distinctive.
Jingbao Li, Keqing Wen , Erkang Zhu , Jingyi Wang
Acta Protozoologica, Volume 58, Issue 4, 2019, pp. 191 - 200
https://doi.org/10.4467/16890027AP.19.017.12019A soil urostylid ciliate Extraholosticha sylvatica, isolated from southern China, is studied using live observation and protargol impregnation. The main ontogenetic features of E. sylvatica are as follows: (a) in the proter, only the posterior part of the parental adoral zone of membranelles is renewed, while the anterior portion is retained; undulating membranes anlage undergo, like most hypotrichs, depolymerization of old undulating membranes and differentiation of new structures; (b) the oral primordium in the opisthe and the frontoventraltransverse cirral anlagen in both daughter cells are formed with contribution of the parental midventral cirri; (c) three frontal, one buccal, three to five frontoventral, one or two frontoterminal, two or three pretransverse ventral and six to 11 transverse cirri and 16–22 midventral pairs are generated from frontoventral-transverse cirral anlagen; (d) in both the left and the right marginal rows as well as the dorsal kineties, each two anlagen are formed intrakinetally; three to six caudal cirri are formed at the posterior end of the 5th dorsal kinety anlage; (e) the macronuclear nodules fuse into a single mass during the process.
Najla Baković, Ferry J. Siemensma , Robert Baković, Josip Rubinić
Acta Protozoologica, Volume 58, Issue 4, 2019, pp. 201 - 215
https://doi.org/10.4467/16890027AP.19.018.12020Karst freshwater caves are subterranean habitats characterized by the constant absence of light and relatively small variations of temperature and air humidity. They are mostly food deprived environments, with the exception if large bat colonies are present or if they are intensively supplied with organic matter by sinking rivers. Even though these habitats are often described as harsh, they have enabled the evolution of highly specialized and often endemic animals. The cave eukaryotic micro-organisms, on the other hand, are scarcely researched. The results of research of testate amoebae in the caves of the Dinaric arc detected 23 species, 12 of which were first found in caves. Also, a description of Centropyxis bipilata sp. nov. is presented. This species is clearly distinguished from other described species based on shell size, the presence of two struts and the usually dark ring around the aperture. Testate amoebae were registered on aquatic and terrestrial cave sediments and transitional habitats (like hygropetric and wet walls). The most frequent species within the samples were: Trinema lineare, Cryptodifflugia oviformis and Centropyxis bipilata sp. nov. Maximum diversity of testate amoebae was registered in Ponor Kovači with twenty species. In 24.4 % of the investigated samples microphototrophs were found, implying good surface-subsurface connectivity that could also affect testate amoebae diversity. This research showed that caves are underestimated habitats that can provide us with new data about the testate amoebae biogeography and diversity.
Giulia M. Ribeiro, Paulo Inácio Prado , Renato Mendes Coutinho , Marina Costa Rillo , Samuel Pereira Junior, Alfredo L. Porfírio-Sousa, Daniel J. G. Lahr
Acta Protozoologica, Volume 58, Issue 4, 2019, pp. 217 - 233
https://doi.org/10.4467/16890027AP.19.019.12021Coexistence usually are exceeding the explicable rate by competitive exclusion principle. Since the pioneer Gause, many studies have used protist microcosm systems to study competitive exclusion. We explored a two-species system with the testate-amoebae: (Arcella intermedia and Pyxidicula operculata), where competitive exclusion is expected to occur. We determined their growth curves individually and under competitive interaction. We used a state-space model to represent system dynamics and calculated posterior population sizes simulating competition dynamics. Contrarily to our expectation, Arcella and Pyxidicula showed similar growth rates (1.37 and 1.46 days–1 respectively) and only different carrying capacity (1,997 and 25,108 cells cm–2 respectively). The maximum number of cells of both species when growing in competition was much lower if compared to the monospecific cultures (in average, 73% and 80% less for Arcella and Pyxidicula respectively). However, our competition experiments always resulted in coexistence. According to the models, the drop in growth rates and stochasticity mainly explains our coexistence results. We propose that a context of ephemeral resources can explain these results. Additionally, we propose generating factors of stochasticity as intraspecific variation, small population effects, toxicity of waste products and influence of the bacterial community.
Publication date: 24.09.2019
Editor-in-Chief: Krzysztof Wiąckowski
Photo on the cover fromr: De Jager G. P., Basson L., Van Marwijk J. (2019) A New Trichodina Species (Peritrichia: Mobilida) from Anuran Tadpole Hosts, Sclerophrys spp. in the Okavango Panhandle, Botswana, with Comments on this Taxon. Acta Protozool. 58: 141-153.
Peter Vďačný, Wilhelm Foissner
Acta Protozoologica, Volume 58, Issue 3, 2019, pp. 93 - 113
https://doi.org/10.4467/16890027AP.19.010.11419The morphology and ontogenesis of a new psilotrichid ciliate, Hemiholosticha pantanalensis, were studied using live observation, protargol impregnation, and scanning electron microscopy. Diagnostic features of the new species include: a medium-sized, almost circular to broadly obovate body with a short anterior projection; two macronuclear nodules with a single micronucleus in between; a total of about 35 cirri arranged in three ventral, one postoral, one right and one left marginal row; three dorsal kineties extending along prominent ribs; an adoral zone occupying about 60% of body length; and intracellular, eyespot-bearing, green algae almost filling the body. The ontogenesis of H. pantanalensis follows the psilotrichid mode, being a mixture of features found not only in various hypotrich taxa but also in other spirotrich groups. Specifically, the oral primordium develops in a deep pouch as in euplotids and oligotrichs, the anlage for the undulating membranes does not produce cirri as in euplotids and some schmidingerothrichids, and the longitudinal ventral cirral row R3 develops from two anlagen as in some amphisiellids and kahliellids. Since psilotrichids are classified in a polytomy of main hypotrich lineages in 18S rRNA gene phylogenies, some of their ontogenetic features might be ancient spirotrich plesiomorphies while others might be homoplasies.
Fernando Gómez, Yasuhide Nakamura , Luis F. Artigas
Acta Protozoologica, Volume 58, Issue 3, 2019, pp. 115 - 124
https://doi.org/10.4467/16890027AP.19.012.11421The molecular phylogeny of the sand-dwelling dinoflagellate Planodinium striatum was investigated from isolates collected in the NE English Channel. In the SSU rRNA gene phylogeny, the sequences of Planodinium clustered with the type species of Plagiodinium, P. belizeanum, and more distantly related to Plagiodinium ballux. Although the SSU rRNA gene sequences of Planodinium showed a high percentage of identity (96%) with partial sequences of species of Podolampas (~1200 base pairs), the SSU rRNA gene phylogenies did not show a relationship with the clade of the Podolampadaceae (Podolampas, Blepharocysta, Roscoffia), neither with the sequences of the sanddwelling genus Cabra. The SSU rRNA gene sequences of Plagiodinium belizeanum and P. ballux showed a low percentage of identity (96%) clustering in separate clades in the SSU rRNA gene phylogeny with Planodinium. The morphology of P. ballux and its generic type differed in the plate arrangement and the morphology of the cingulum, amongst other features. Based on the morphological and molecular differences, we propose the new genus Chrysodinium gen. nov. for P. ballux, with the re-interpreted thecal plate formula Po 3’ 1’’ 7c 2s 5’’’ 1’’’’.
Gerhard P. de Jager, Linda Basson
Acta Protozoologica, Volume 58, Issue 3, 2019, pp. 125 - 139
https://doi.org/10.4467/16890027AP.19.013.11914Trichodina heterodentata was first described from fish breeding farms in the Philippines by Bryan Duncan in 1977 as ectoparasites of imported cichlids, more specifically the southern African Oreochromis mossambicus (Peters, 1852) from the Limpopo River System. This trichodinid has subsequently been described from almost every continent, bar North America. Being a cosmopolitan species, with a preference for cichlid hosts, it has unambiguous morphological features, but with distinct variances between and within populations. After reviewing previous descriptions of North American trichodinids, analysing the morphological data (both generally published information along with the original type material from the Smithsonian Museum, Washington, U.S.A.) and investigating the distribution patterns of the southern African introduced O. mossambicus throughout the North American water systems, three of the four studied trichodinids (T. hypsilepis Wellborn, 1967, T. salmincola Wellborn, 1967 and T. vallata Wellborn, 1967) are proposed to represent the same species as T. heterodentata. According to nomenclature rules T. hypsilepis henceforth represents the valid taxon (synonyms: T. salmincola, T. vallata and T. heterodentata). This not only questions the validity of several trichodinid species, but also indicates the probability of an African alien introduction into North America.
Gerhard P. de Jager, Linda Basson, Jacqueline van Marwijk
Acta Protozoologica, Volume 58, Issue 3, 2019, pp. 141 - 153
https://doi.org/10.4467/16890027AP.19.014.11915Mobiline taxonomic data is mostly inferred from populations collected in and on hosts associated with aquaculture. Even though these conditions may be conducive for studies relating to the hosts, accurate taxonomic inferences of the symbionts will be problematic. The site for the present study was the Okavango Panhandle region in Northern Botswana, an isolated, natural area with minimal anthropogenic influences. Morphometric and molecular evidence revealed that anuran tadpole trichodinids, up to now reported as Trichodina heterodentata Duncan 1977 and T. hypsilepis Wellborn 1967 from multiple host types, are in fact a new, more host specific species. This study includes comprehensive denticle descriptions of both the anuran hosted trichodinid and the morphologically similar T. hypsilepis restricted to teleost hosts (previously T. heterodentata).
Carlos Alberto Durán-Ramirez, Rosaura Mayén-Estrada, Víctor Manuel Romero-Niembro
Acta Protozoologica, Volume 58, Issue 3, 2019, pp. 155 - 165
https://doi.org/10.4467/16890027AP.19.015.11916To understand distributional and ecological aspects of ciliates living in tank bromeliads, we analyzed the ciliate community structure in fifteen different epiphytic and terrestrial bromeliad species from different types of vegetation. Sixty-nine samples were collected from plants of genera Aechmea, Bromelia, Pseudalcantarea and Tillandsia in seven localities in eastern Mexico during 2014 and 2015. The sampling localities covered an altitude gradient from 0 till 2 210 m ASL. We found 24 ciliate species and through the application of a principal component analysis, three clusters that correspond to several types of vegetation were obtained with regard to ciliate and bromeliad species. We recorded the largest number of ciliate species in localities of montane cloud forest, and also the largest number of ciliate species endemic to tank bromeliads, like Glaucomides bromelicola, inhabiting bromeliads from this forest. We observed the presence of ciliates in Bromelia pinguin that possesses a weakly developed phytotelm. The results of our study indicate that the species composition of ciliates inhabiting tank bromeliads depends on such correlated environmental factors like altitude ASL, temperature and type of vegetation.
Peter Vďačný, Wilhelm Foissner
Acta Protozoologica, Volume 58, Issue 3, 2019, pp. 93 - 113
https://doi.org/10.4467/16890027AP.19.010.11419The morphology and ontogenesis of a new psilotrichid ciliate, Hemiholosticha pantanalensis, were studied using live observation, protargol impregnation, and scanning electron microscopy. Diagnostic features of the new species include: a medium-sized, almost circular to broadly obovate body with a short anterior projection; two macronuclear nodules with a single micronucleus in between; a total of about 35 cirri arranged in three ventral, one postoral, one right and one left marginal row; three dorsal kineties extending along prominent ribs; an adoral zone occupying about 60% of body length; and intracellular, eyespot-bearing, green algae almost filling the body. The ontogenesis of H. pantanalensis follows the psilotrichid mode, being a mixture of features found not only in various hypotrich taxa but also in other spirotrich groups. Specifically, the oral primordium develops in a deep pouch as in euplotids and oligotrichs, the anlage for the undulating membranes does not produce cirri as in euplotids and some schmidingerothrichids, and the longitudinal ventral cirral row R3 develops from two anlagen as in some amphisiellids and kahliellids. Since psilotrichids are classified in a polytomy of main hypotrich lineages in 18S rRNA gene phylogenies, some of their ontogenetic features might be ancient spirotrich plesiomorphies while others might be homoplasies.
Fernando Gómez, Yasuhide Nakamura , Luis F. Artigas
Acta Protozoologica, Volume 58, Issue 3, 2019, pp. 115 - 124
https://doi.org/10.4467/16890027AP.19.012.11421The molecular phylogeny of the sand-dwelling dinoflagellate Planodinium striatum was investigated from isolates collected in the NE English Channel. In the SSU rRNA gene phylogeny, the sequences of Planodinium clustered with the type species of Plagiodinium, P. belizeanum, and more distantly related to Plagiodinium ballux. Although the SSU rRNA gene sequences of Planodinium showed a high percentage of identity (96%) with partial sequences of species of Podolampas (~1200 base pairs), the SSU rRNA gene phylogenies did not show a relationship with the clade of the Podolampadaceae (Podolampas, Blepharocysta, Roscoffia), neither with the sequences of the sanddwelling genus Cabra. The SSU rRNA gene sequences of Plagiodinium belizeanum and P. ballux showed a low percentage of identity (96%) clustering in separate clades in the SSU rRNA gene phylogeny with Planodinium. The morphology of P. ballux and its generic type differed in the plate arrangement and the morphology of the cingulum, amongst other features. Based on the morphological and molecular differences, we propose the new genus Chrysodinium gen. nov. for P. ballux, with the re-interpreted thecal plate formula Po 3’ 1’’ 7c 2s 5’’’ 1’’’’.
Gerhard P. de Jager, Linda Basson
Acta Protozoologica, Volume 58, Issue 3, 2019, pp. 125 - 139
https://doi.org/10.4467/16890027AP.19.013.11914Trichodina heterodentata was first described from fish breeding farms in the Philippines by Bryan Duncan in 1977 as ectoparasites of imported cichlids, more specifically the southern African Oreochromis mossambicus (Peters, 1852) from the Limpopo River System. This trichodinid has subsequently been described from almost every continent, bar North America. Being a cosmopolitan species, with a preference for cichlid hosts, it has unambiguous morphological features, but with distinct variances between and within populations. After reviewing previous descriptions of North American trichodinids, analysing the morphological data (both generally published information along with the original type material from the Smithsonian Museum, Washington, U.S.A.) and investigating the distribution patterns of the southern African introduced O. mossambicus throughout the North American water systems, three of the four studied trichodinids (T. hypsilepis Wellborn, 1967, T. salmincola Wellborn, 1967 and T. vallata Wellborn, 1967) are proposed to represent the same species as T. heterodentata. According to nomenclature rules T. hypsilepis henceforth represents the valid taxon (synonyms: T. salmincola, T. vallata and T. heterodentata). This not only questions the validity of several trichodinid species, but also indicates the probability of an African alien introduction into North America.
Gerhard P. de Jager, Linda Basson, Jacqueline van Marwijk
Acta Protozoologica, Volume 58, Issue 3, 2019, pp. 141 - 153
https://doi.org/10.4467/16890027AP.19.014.11915Mobiline taxonomic data is mostly inferred from populations collected in and on hosts associated with aquaculture. Even though these conditions may be conducive for studies relating to the hosts, accurate taxonomic inferences of the symbionts will be problematic. The site for the present study was the Okavango Panhandle region in Northern Botswana, an isolated, natural area with minimal anthropogenic influences. Morphometric and molecular evidence revealed that anuran tadpole trichodinids, up to now reported as Trichodina heterodentata Duncan 1977 and T. hypsilepis Wellborn 1967 from multiple host types, are in fact a new, more host specific species. This study includes comprehensive denticle descriptions of both the anuran hosted trichodinid and the morphologically similar T. hypsilepis restricted to teleost hosts (previously T. heterodentata).
Carlos Alberto Durán-Ramirez, Rosaura Mayén-Estrada, Víctor Manuel Romero-Niembro
Acta Protozoologica, Volume 58, Issue 3, 2019, pp. 155 - 165
https://doi.org/10.4467/16890027AP.19.015.11916To understand distributional and ecological aspects of ciliates living in tank bromeliads, we analyzed the ciliate community structure in fifteen different epiphytic and terrestrial bromeliad species from different types of vegetation. Sixty-nine samples were collected from plants of genera Aechmea, Bromelia, Pseudalcantarea and Tillandsia in seven localities in eastern Mexico during 2014 and 2015. The sampling localities covered an altitude gradient from 0 till 2 210 m ASL. We found 24 ciliate species and through the application of a principal component analysis, three clusters that correspond to several types of vegetation were obtained with regard to ciliate and bromeliad species. We recorded the largest number of ciliate species in localities of montane cloud forest, and also the largest number of ciliate species endemic to tank bromeliads, like Glaucomides bromelicola, inhabiting bromeliads from this forest. We observed the presence of ciliates in Bromelia pinguin that possesses a weakly developed phytotelm. The results of our study indicate that the species composition of ciliates inhabiting tank bromeliads depends on such correlated environmental factors like altitude ASL, temperature and type of vegetation.
Publication date: 31.10.2019
Editor-in-Chief: Krzysztof Wiąckowski
Photo on the cover fromr: De Jager G. P., Basson L., Van Marwijk J. (2019) A New Trichodina Species (Peritrichia: Mobilida) from Anuran Tadpole Hosts, Sclerophrys spp. in the Okavango Panhandle, Botswana, with Comments on this Taxon. Acta Protozool. 58: 141-153.
Kang-San Kim, Kyu-Seok Chae, Gi-Sik Min
Acta Protozoologica, Volume 58, Issue 2, 2019, pp. 43 - 51
https://doi.org/10.4467/16890027AP.19.005.10836A new marine urostylid ciliate, Arcuseries minima sp. nov., was discovered in South Korea. Morphological observations and molecular phylogenetic analyses based on small subunit ribosomal DNA (18S rDNA) sequences were used to describe the new species. Arcuseries minima is most similar to A. scutellum among all Arcuseries species, but differs in the following main characters: number of adoral membranelles (13–16 vs. 17 or 18), cortical granules (yellowish, clustered around cirri and dorsal bristles vs. colorless, irregularly scattered), number of macronuclear nodules (20–27 vs. 42–90), number of midventral cirri (5–10 vs. 12–14), and number f transverse cirri (5 or 6 vs. 8). The new species and A. scutellum differ from A. petzi and A. warreni in having smaller body size (≤80 μm vs. ≥80 μm) and fewer cirri: left marginal (≤ 17 vs. ≥ 18) and transverse (≤ 8 vs. ≥8) cirri. This relationship was supported by the phylogenetic tree, where these two groups were separated into two branches.
Ľubomír Rajter, William Bourland, Peter Vďačný
Acta Protozoologica, Volume 58, Issue 2, 2019, pp. 53 - 68
https://doi.org/10.4467/16890027AP.19.004.10835The morphology and phylogenetic position of a haptorian ciliate, Phialina pupula (Müller, 1773) Foissner, 1983, isolated from microaerobic sandy sediments of the floodplain area of the Boise River, Idaho, U.S.A., were studied using live observation, protargol impregnation, scanning electron microscopy, and the 18S rRNA gene as well as the ITS region. The Boise population of P. pupula is characterized by a size of about 60–130 × 20–50 μm, an elliptical macronucleus with a single micronucleus, highly refractive dumbbell-shaped inclusions scattered throughout the cytoplasm and concentrated in the anterior body half, a single subterminal/terminal contractile vacuole, about 10 μm long rod-shaped extrusomes, and an average of 15 ciliary rows. In phylogenetic analyses, the newly obtained sequences from P. pupula and Lacrymaria olor clustered within the family Lacrymariidae with full to moderate statistical support. Neither the genus Phialina nor the genus Lacrymaria was depicted monophyletic both in the single gene and multigene phylogenetic inferences. Specifically, the genus Phialina was shown as a paraphyletic assemblage containing members of the polyphyletic genus Lacrymaria. This indicates that the phialinid bauplan, i.e., an anterior body end differentiated into a head-like structure directly attached to the trunk, might represent the ground pattern in the family Lacrymariidae. On the other hand, the long highly contractile neck carrying the head-like structure probably evolved later and convergently in multiple Lacrymaria species from Phialina-like ancestors.
Volodymyr Yuryshynets, Markéta Ondračková, Yuriy Kvach, Gérard Masson
Acta Protozoologica, Volume 58, Issue 2, 2019, pp. 69 - 79
https://doi.org/10.4467/16890027AP.19.009.11418Three species of trichodinid ciliates, common parasites or symbionts of aquatic invertebrates and vertebrates, have been reported from pumpkinseed (Lepomis gibbosus, Centrarchidae) in both their native (Trichodina fultoni, T. tumefaciens) and introduced (T. fultoni, Trichodinella epizootica) ranges. In this study, we report five additional trichodinid taxa collected from invasive L. gibbosus in France and two regions of the Czech Republic. We describe a new species, Trichodina lepomi sp. n., recorded in L. gibbosus from both countries. The new species differs from T. nigra by absence of posterior projection of blade, absence of notch/ indentation opposing ray apophysis, absence of ray apophysis and the blade not being displaced anteriorly relative to ray as significantly as in T. nigra. Two widely distributed species, identified as Trichodina acuta and T. cf. heterodentata, were observed on juvenile fish in the Dyje river basin (Czech Republic). Finally, two undescribed species f Trichodina sp. and Tripartiella sp. are reported. Detailed description of the new species and comparison with other congeneric species are presented.
Felipe S. Coelho, Danielle P. Vieira, Angela H. Lopes, Maria A. Sousa
Acta Protozoologica, Volume 58, Issue 2, 2019, pp. 81 - 88
https://doi.org/10.4467/16890027AP.19.011.11420The protein profiles of the epimastigote stages from eight reference strains of Trypanosoma cruzi belonging to three different lineages (TcI, TcII and TcVI) were analyzed by SDS-PAGE (sodium dodecyl sulphate-polyacrylamide gel electrophoresis), under standardized conditions. More than 40 protein bands were observed in each strain. Around 55% of them were not shared by all stocks (non-conserved proteins), representing their intra-specific variability. Then, they were coded for processing by numerical taxonomy, using three association coefficients and the UPGMA clustering algorithm. With all coefficients assayed, two major groups were clearly seen, confirming the dichotomy within T. cruzi taxon, as demonstrated by other molecular and biochemical approaches. In the present study, the term peptideme was used to name the groups of strains based on their polypeptide profiles, following the above-cited methodology. Then, two major peptidemes were identified, each one presenting subdivisions. The isolates identified as TcI clustered in the same major peptideme, displaying a subgroup with the opossum isolates (G, SC28, Dm28c) apart from the stock of human origin (Colombian strain). The other major peptideme also showed two subgroups, regardless the coefficient used. One of them included the TcII strains (Y, SF21), both from Brazilian patients, and the other the TcVI stocks, both originally from triatomines from Southern Brazil (CL Brener, FL). As far we know, this is the first report on the parity between the T. cruzi lineages consensually accepted and their grouping into peptidemes based on SDS-PAGE and the numerical analysis of non-conserved proteins.
J. Antonio Heredia-Rojas, Abraham O. Rodríguez-De la Fuente, Ricardo Gomez-Flores, Merary Alvarez-Rodríguez, Zinnia J. Molina-Garza, M. Beltcheva, Omar Heredia-Rodríguez, Lucio Galaviz-Silva
Acta Protozoologica, Volume 58, Issue 2, 2019, pp. 89 - 92
https://doi.org/10.4467/16890027AP.19.008.11417The influence of extremely low-frequency electromagnetic fields (ELF-EMFs) on microorganisms has been a subject of experimental investigations with promising results. In the present study, it was demonstrated that 2.0 mT 60Hz ELF-EMFs inhibited Trypanosoma cruzi epimastigotes growth. In addition, no synergistic or antagonistic parasite growth and viability effects were observed after cultures were co-exposed to magnetic fields and Nifurtimox, a well-known anti-trypanosome drug. Moreover, the current study represents the first report regarding direct magnetic fields effects on Trypanosomas.
Kang-San Kim, Kyu-Seok Chae, Gi-Sik Min
Acta Protozoologica, Volume 58, Issue 2, 2019, pp. 43 - 51
https://doi.org/10.4467/16890027AP.19.005.10836A new marine urostylid ciliate, Arcuseries minima sp. nov., was discovered in South Korea. Morphological observations and molecular phylogenetic analyses based on small subunit ribosomal DNA (18S rDNA) sequences were used to describe the new species. Arcuseries minima is most similar to A. scutellum among all Arcuseries species, but differs in the following main characters: number of adoral membranelles (13–16 vs. 17 or 18), cortical granules (yellowish, clustered around cirri and dorsal bristles vs. colorless, irregularly scattered), number of macronuclear nodules (20–27 vs. 42–90), number of midventral cirri (5–10 vs. 12–14), and number f transverse cirri (5 or 6 vs. 8). The new species and A. scutellum differ from A. petzi and A. warreni in having smaller body size (≤80 μm vs. ≥80 μm) and fewer cirri: left marginal (≤ 17 vs. ≥ 18) and transverse (≤ 8 vs. ≥8) cirri. This relationship was supported by the phylogenetic tree, where these two groups were separated into two branches.
Ľubomír Rajter, William Bourland, Peter Vďačný
Acta Protozoologica, Volume 58, Issue 2, 2019, pp. 53 - 68
https://doi.org/10.4467/16890027AP.19.004.10835The morphology and phylogenetic position of a haptorian ciliate, Phialina pupula (Müller, 1773) Foissner, 1983, isolated from microaerobic sandy sediments of the floodplain area of the Boise River, Idaho, U.S.A., were studied using live observation, protargol impregnation, scanning electron microscopy, and the 18S rRNA gene as well as the ITS region. The Boise population of P. pupula is characterized by a size of about 60–130 × 20–50 μm, an elliptical macronucleus with a single micronucleus, highly refractive dumbbell-shaped inclusions scattered throughout the cytoplasm and concentrated in the anterior body half, a single subterminal/terminal contractile vacuole, about 10 μm long rod-shaped extrusomes, and an average of 15 ciliary rows. In phylogenetic analyses, the newly obtained sequences from P. pupula and Lacrymaria olor clustered within the family Lacrymariidae with full to moderate statistical support. Neither the genus Phialina nor the genus Lacrymaria was depicted monophyletic both in the single gene and multigene phylogenetic inferences. Specifically, the genus Phialina was shown as a paraphyletic assemblage containing members of the polyphyletic genus Lacrymaria. This indicates that the phialinid bauplan, i.e., an anterior body end differentiated into a head-like structure directly attached to the trunk, might represent the ground pattern in the family Lacrymariidae. On the other hand, the long highly contractile neck carrying the head-like structure probably evolved later and convergently in multiple Lacrymaria species from Phialina-like ancestors.
Volodymyr Yuryshynets, Markéta Ondračková, Yuriy Kvach, Gérard Masson
Acta Protozoologica, Volume 58, Issue 2, 2019, pp. 69 - 79
https://doi.org/10.4467/16890027AP.19.009.11418Three species of trichodinid ciliates, common parasites or symbionts of aquatic invertebrates and vertebrates, have been reported from pumpkinseed (Lepomis gibbosus, Centrarchidae) in both their native (Trichodina fultoni, T. tumefaciens) and introduced (T. fultoni, Trichodinella epizootica) ranges. In this study, we report five additional trichodinid taxa collected from invasive L. gibbosus in France and two regions of the Czech Republic. We describe a new species, Trichodina lepomi sp. n., recorded in L. gibbosus from both countries. The new species differs from T. nigra by absence of posterior projection of blade, absence of notch/ indentation opposing ray apophysis, absence of ray apophysis and the blade not being displaced anteriorly relative to ray as significantly as in T. nigra. Two widely distributed species, identified as Trichodina acuta and T. cf. heterodentata, were observed on juvenile fish in the Dyje river basin (Czech Republic). Finally, two undescribed species f Trichodina sp. and Tripartiella sp. are reported. Detailed description of the new species and comparison with other congeneric species are presented.
Felipe S. Coelho, Danielle P. Vieira, Angela H. Lopes, Maria A. Sousa
Acta Protozoologica, Volume 58, Issue 2, 2019, pp. 81 - 88
https://doi.org/10.4467/16890027AP.19.011.11420The protein profiles of the epimastigote stages from eight reference strains of Trypanosoma cruzi belonging to three different lineages (TcI, TcII and TcVI) were analyzed by SDS-PAGE (sodium dodecyl sulphate-polyacrylamide gel electrophoresis), under standardized conditions. More than 40 protein bands were observed in each strain. Around 55% of them were not shared by all stocks (non-conserved proteins), representing their intra-specific variability. Then, they were coded for processing by numerical taxonomy, using three association coefficients and the UPGMA clustering algorithm. With all coefficients assayed, two major groups were clearly seen, confirming the dichotomy within T. cruzi taxon, as demonstrated by other molecular and biochemical approaches. In the present study, the term peptideme was used to name the groups of strains based on their polypeptide profiles, following the above-cited methodology. Then, two major peptidemes were identified, each one presenting subdivisions. The isolates identified as TcI clustered in the same major peptideme, displaying a subgroup with the opossum isolates (G, SC28, Dm28c) apart from the stock of human origin (Colombian strain). The other major peptideme also showed two subgroups, regardless the coefficient used. One of them included the TcII strains (Y, SF21), both from Brazilian patients, and the other the TcVI stocks, both originally from triatomines from Southern Brazil (CL Brener, FL). As far we know, this is the first report on the parity between the T. cruzi lineages consensually accepted and their grouping into peptidemes based on SDS-PAGE and the numerical analysis of non-conserved proteins.
J. Antonio Heredia-Rojas, Abraham O. Rodríguez-De la Fuente, Ricardo Gomez-Flores, Merary Alvarez-Rodríguez, Zinnia J. Molina-Garza, M. Beltcheva, Omar Heredia-Rodríguez, Lucio Galaviz-Silva
Acta Protozoologica, Volume 58, Issue 2, 2019, pp. 89 - 92
https://doi.org/10.4467/16890027AP.19.008.11417The influence of extremely low-frequency electromagnetic fields (ELF-EMFs) on microorganisms has been a subject of experimental investigations with promising results. In the present study, it was demonstrated that 2.0 mT 60Hz ELF-EMFs inhibited Trypanosoma cruzi epimastigotes growth. In addition, no synergistic or antagonistic parasite growth and viability effects were observed after cultures were co-exposed to magnetic fields and Nifurtimox, a well-known anti-trypanosome drug. Moreover, the current study represents the first report regarding direct magnetic fields effects on Trypanosomas.
Publication date: 25.07.2019
Editor-in-Chief: Krzysztof Wiąckowski
Photo on the cover fromr: De Jager G. P., Basson L., Van Marwijk J. (2019) A New Trichodina Species (Peritrichia: Mobilida) from Anuran Tadpole Hosts, Sclerophrys spp. in the Okavango Panhandle, Botswana, with Comments on this Taxon. Acta Protozool. 58: 141-153.
Piotr Solarczyk, Natalia Osten-Sacken, Alain C. Frantz, Simone Schneider, Jacques B. Pir, Mike Heddergott
Acta Protozoologica, Volume 58, Issue 1, 2019, pp. 1 - 5
https://doi.org/10.4467/16890027AP.19.001.10832Giardia duodenalis is one of the most widespread intestinal parasites of humans and other vertebrates. In terms of public health, identification of Giardia assemblages in wildlife is important because only some assemblages of G. duodenalis can infect humans. Here, we use loop-mediated isothermal amplification (LAMP) and genotyping of analysis of the β-giardin gene to screen the zoonotic assemblages of G. duodenalis recovered from faeces of free-living European wildcats (Felis s. silvestris) from Luxembourg. Giardia DNA was detected in one animal (10%) and assigned to assemblage B by both methods. This is the first detection and genotyping of G. duodenalis in a European wild felid in general, and of assemblage B in particular. Free-living wildcats may act as reservoirs of G. duodenalis infectious for humans and other wildlife and domestic animals. Using a combination of LAMP- and genotyping-based methods allowed effective, sensitive, and rapid detection of a zoonotic G. duodenalis assemblage B in wildlife.
Elideth Pacheco Monteiro, Diehgo Tuloza Da Silva, Osimar Sanches, Igor Hamoy, Edilson Rodrigues Matos
Acta Protozoologica, Volume 58, Issue 1, 2019, pp. 7 - 16
https://doi.org/10.4467/16890027AP.19.002.10833A new species of myxozoan, Kudoa viseuensis n. sp. (Myxosporea: Multivalvulida), is described based on specimens extracted from the musculature of the Pacuma toadfish, Batrachoides surinamensis, collected in the municipality of Viseu, in the northern Brazilian state of Pará. A total of 60 specimens of B. surinamensis were examined, of which 52 (86%) presented whitish pseudocysts containing numerous rounded spores (7.2±0.2 μm in length and 5.2±0.2 μm in width). These spores have four polar capsules of equal size, measuring 1.8±0.2 μm x 1.3±0.1 μm in the apical view, and 2.7±0.2 μm x 1.3±0.1 μm in the lateral view. A partial sequence (1400 bps) of the small subunit ribosomal RNA gene was obtained and deposited in GenBank (access number: MK256272). The comparison of the morphological and molecular data with those of other Kudoa species supported the description of a new species of mixosporean from the Amazon region, which is denominated here as Kudoa viseuensis n. sp.
Jhon Lennon Genovez-Oliveira, Sergian V. Cardozo, Águida A. De Oliveira, Viviane M. De Lima, Ildemar Ferreira, Bruno P. Berto
Acta Protozoologica, Volume 58, Issue 1, 2019, pp. 17 - 23
https://doi.org/10.4467/16890027AP.19.007.10838Isospora sepetibensis Berto, Flausino, Luz, Ferreira and Lopes, 2008 is a protozoan coccidian parasite (Chromista: Miozoa: Coccidiomorphea: Coccidia) that was originally described from Brazilian tanagers Ramphocelus bresilius (Linnaeus, 1766) in the Marambaia Island in the Coast of the State of Rio de Janeiro. In the current work, this species was identified from black-goggled tanagers Trichothraupis melanops (Vieillot, 1818) in the Itatiaia National Park, which is a protected area with a high degree of vulnerability in the interior of the State of Rio de Janeiro, distant in more than 100 km of the type-locality. Its oocysts are sub-spherical to elongate ovoidal, 25.9 × 20.7 μm with smooth, bi-layered wall, ~ 1.3 μm and length/width ratio of 1.1–1.4 (1.26). Micropyle and oocyst residuum absent, but one or two polar granules are present. Sporocysts are ellipsoidal, 16.8 × 10.3 μm, with both Stieda and sub-Stieda bodies. Sporocyst residuum present and sporozoites with refractile body and nucleus. Molecular analysis was conducted at the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. This new isolate exhibited similarity greater than 98% with Isospora spp. isolates from other Neotropical passerines and with an Isospora sp. pseudoparasite of voles of Eurasia. This is the first coccidian parasite from a New World tanager to have a molecular identification of the cox1 gene.
Yoichiro Sogame, Ryota Saito, Ryota Koizumi, Taiga Shimizu, Taiki Ono
Acta Protozoologica, Volume 58, Issue 1, 2019, pp. 25 - 29
https://doi.org/10.4467/16890027AP.19.006.10837In this study, we report that the unicellular free-living protist Colpoda cucullus in the resting cyst (cryptobiosis) repairs stress damage. We previously demonstrated that resting cysts of Colpoda cucullus have extreme tolerance to gamma irradiation and can revert to vegetative cells after irradiation. Such irradiated cysts gradually excyst, suggesting that stress repair mechanisms are active during excystment or in the resting cyst. Herein we provide bioassay evidence that the rate of excystment of irradiated cysts is elevated by subsequent incubation, thereby indicating that cells injured by gamma irradiation can repair themselves in the resting cyst, whereas irradiated dry cysts cannot.
J. Mercy Nisha Pauline, Anant Achary
Acta Protozoologica, Volume 58, Issue 1, 2019, pp. 31 - 41
https://doi.org/10.4467/16890027AP.19.003.10834The algal medium was optimized to increase the biomass and lipid production of Chlorococcum oleofaciens. The significant variables were screened and chosen from previously reported algal culture media using Plackett Burman Design (PBD). Optimization of the significant variables were performed using central composite design. The Pareto chart for PBD revealed that the salts such as sodium bicarbonate, sodium nitrate, potassium nitrate and ferrous sulphate had enhanced the biomass and lipid production. The variables and its effect on the responses were further studied by central composite design (CCD). A new medium was formulated based on the response surface methodology. The predicted concentration of NaHCO3, NaNO3, KNO3, MgSO4.7H2O were found to be 6.75 g/L, 0.75 g/L, 1.88 g/L and 0.35 g/L respectively. The actual and the predicted total lipid yield for the optimized media was around 0.74 g/L and 0.78 g/L respectively. The optimal medium has been named as AM medium. Growth and the lipid yields of C. oleofaciens were found higher in AM medium. The specific growth rates of C. oleofaciens in AM and CFTRI media were found to be 0.14 day-1 and 0.19 day-1 respectively. The biomass produced by the optimized AM medium was found to be 2.7 times greater compared to the CFTRI medium. The lipid was extracted and GC-MS was performed which revealed that the fatty acids were predominantly of the class C15:0, C18:0, C16:0 and C12:0. It is concluded that besides lipid content, AM medium increased the cell number leading to the increase in biomass.
Piotr Solarczyk, Natalia Osten-Sacken, Alain C. Frantz, Simone Schneider, Jacques B. Pir, Mike Heddergott
Acta Protozoologica, Volume 58, Issue 1, 2019, pp. 1 - 5
https://doi.org/10.4467/16890027AP.19.001.10832Giardia duodenalis is one of the most widespread intestinal parasites of humans and other vertebrates. In terms of public health, identification of Giardia assemblages in wildlife is important because only some assemblages of G. duodenalis can infect humans. Here, we use loop-mediated isothermal amplification (LAMP) and genotyping of analysis of the β-giardin gene to screen the zoonotic assemblages of G. duodenalis recovered from faeces of free-living European wildcats (Felis s. silvestris) from Luxembourg. Giardia DNA was detected in one animal (10%) and assigned to assemblage B by both methods. This is the first detection and genotyping of G. duodenalis in a European wild felid in general, and of assemblage B in particular. Free-living wildcats may act as reservoirs of G. duodenalis infectious for humans and other wildlife and domestic animals. Using a combination of LAMP- and genotyping-based methods allowed effective, sensitive, and rapid detection of a zoonotic G. duodenalis assemblage B in wildlife.
Elideth Pacheco Monteiro, Diehgo Tuloza Da Silva, Osimar Sanches, Igor Hamoy, Edilson Rodrigues Matos
Acta Protozoologica, Volume 58, Issue 1, 2019, pp. 7 - 16
https://doi.org/10.4467/16890027AP.19.002.10833A new species of myxozoan, Kudoa viseuensis n. sp. (Myxosporea: Multivalvulida), is described based on specimens extracted from the musculature of the Pacuma toadfish, Batrachoides surinamensis, collected in the municipality of Viseu, in the northern Brazilian state of Pará. A total of 60 specimens of B. surinamensis were examined, of which 52 (86%) presented whitish pseudocysts containing numerous rounded spores (7.2±0.2 μm in length and 5.2±0.2 μm in width). These spores have four polar capsules of equal size, measuring 1.8±0.2 μm x 1.3±0.1 μm in the apical view, and 2.7±0.2 μm x 1.3±0.1 μm in the lateral view. A partial sequence (1400 bps) of the small subunit ribosomal RNA gene was obtained and deposited in GenBank (access number: MK256272). The comparison of the morphological and molecular data with those of other Kudoa species supported the description of a new species of mixosporean from the Amazon region, which is denominated here as Kudoa viseuensis n. sp.
Jhon Lennon Genovez-Oliveira, Sergian V. Cardozo, Águida A. De Oliveira, Viviane M. De Lima, Ildemar Ferreira, Bruno P. Berto
Acta Protozoologica, Volume 58, Issue 1, 2019, pp. 17 - 23
https://doi.org/10.4467/16890027AP.19.007.10838Isospora sepetibensis Berto, Flausino, Luz, Ferreira and Lopes, 2008 is a protozoan coccidian parasite (Chromista: Miozoa: Coccidiomorphea: Coccidia) that was originally described from Brazilian tanagers Ramphocelus bresilius (Linnaeus, 1766) in the Marambaia Island in the Coast of the State of Rio de Janeiro. In the current work, this species was identified from black-goggled tanagers Trichothraupis melanops (Vieillot, 1818) in the Itatiaia National Park, which is a protected area with a high degree of vulnerability in the interior of the State of Rio de Janeiro, distant in more than 100 km of the type-locality. Its oocysts are sub-spherical to elongate ovoidal, 25.9 × 20.7 μm with smooth, bi-layered wall, ~ 1.3 μm and length/width ratio of 1.1–1.4 (1.26). Micropyle and oocyst residuum absent, but one or two polar granules are present. Sporocysts are ellipsoidal, 16.8 × 10.3 μm, with both Stieda and sub-Stieda bodies. Sporocyst residuum present and sporozoites with refractile body and nucleus. Molecular analysis was conducted at the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. This new isolate exhibited similarity greater than 98% with Isospora spp. isolates from other Neotropical passerines and with an Isospora sp. pseudoparasite of voles of Eurasia. This is the first coccidian parasite from a New World tanager to have a molecular identification of the cox1 gene.
Yoichiro Sogame, Ryota Saito, Ryota Koizumi, Taiga Shimizu, Taiki Ono
Acta Protozoologica, Volume 58, Issue 1, 2019, pp. 25 - 29
https://doi.org/10.4467/16890027AP.19.006.10837In this study, we report that the unicellular free-living protist Colpoda cucullus in the resting cyst (cryptobiosis) repairs stress damage. We previously demonstrated that resting cysts of Colpoda cucullus have extreme tolerance to gamma irradiation and can revert to vegetative cells after irradiation. Such irradiated cysts gradually excyst, suggesting that stress repair mechanisms are active during excystment or in the resting cyst. Herein we provide bioassay evidence that the rate of excystment of irradiated cysts is elevated by subsequent incubation, thereby indicating that cells injured by gamma irradiation can repair themselves in the resting cyst, whereas irradiated dry cysts cannot.
J. Mercy Nisha Pauline, Anant Achary
Acta Protozoologica, Volume 58, Issue 1, 2019, pp. 31 - 41
https://doi.org/10.4467/16890027AP.19.003.10834The algal medium was optimized to increase the biomass and lipid production of Chlorococcum oleofaciens. The significant variables were screened and chosen from previously reported algal culture media using Plackett Burman Design (PBD). Optimization of the significant variables were performed using central composite design. The Pareto chart for PBD revealed that the salts such as sodium bicarbonate, sodium nitrate, potassium nitrate and ferrous sulphate had enhanced the biomass and lipid production. The variables and its effect on the responses were further studied by central composite design (CCD). A new medium was formulated based on the response surface methodology. The predicted concentration of NaHCO3, NaNO3, KNO3, MgSO4.7H2O were found to be 6.75 g/L, 0.75 g/L, 1.88 g/L and 0.35 g/L respectively. The actual and the predicted total lipid yield for the optimized media was around 0.74 g/L and 0.78 g/L respectively. The optimal medium has been named as AM medium. Growth and the lipid yields of C. oleofaciens were found higher in AM medium. The specific growth rates of C. oleofaciens in AM and CFTRI media were found to be 0.14 day-1 and 0.19 day-1 respectively. The biomass produced by the optimized AM medium was found to be 2.7 times greater compared to the CFTRI medium. The lipid was extracted and GC-MS was performed which revealed that the fatty acids were predominantly of the class C15:0, C18:0, C16:0 and C12:0. It is concluded that besides lipid content, AM medium increased the cell number leading to the increase in biomass.
Publication date: 12.02.2019
Editor-in-Chief: Krzysztof Wiąckowski
Hoan Q. Trana, Yuri A. Mazei
Acta Protozoologica, Volume 57, Issue 4, 2018, pp. 215 - 229
https://doi.org/10.4467/16890027AP.18.016.10092Testate amoebae in Vietnam are still poorly investigated. We studied species composition of testate amoebae in 47 waterbodies of South Vietnam provinces including natural lakes, reservoirs, wetlands, rivers, and irrigation channels. A total of 109 species and subspecies belonging to 16 genera, 9 families were identified from 191 samples. Thirty-five species and subspecies were observed in Vietnam for the first time. New species Difflugia vietnamica sp. nov. is described. The most species-rich genera are Difflugia (46 taxa), Arcella (25) and Centropyxis (14). Centropyxis aculeata was the most common species (observed in 68.1% samples). Centropyxis aerophila sphagniсola, Arcella discoides, Difflugia schurmanni and Lesquereusia modesta were characterised by a frequency of occurrence >20%. Other species were rarer. The species accumulation curve based on the entire dataset of this work was unsaturated and well fitted by equation S = 19.46N0.33. Species richness per sample in natural lakes and wetlands were significantly higher than that of rivers (p < 0.001). The result of the Spearman rank test shows weak or statistically insignificant relationships between species richness and water temperature, pH, dissolved oxygen, and electrical conductivity.
Horacio Pérez-Juárez, Angélica Serrano-Vázquez, Enrique Lara, Cecilia Ximénez, Héctor Godínez-Alvarez, Salvador Rodríguez-Zaragoza, Luis E. Eguiarte, Mayra M. Hernández Moreno, Leonardo David Fernández, Leonardo D. Fernández , Liliana Rojas-Velázquez, Patricia Morán, Mariela Castillo, Víctor M. Rivera Aguilar
Acta Protozoologica, Volume 57, Issue 4, 2018, pp. 231 - 242
https://doi.org/10.4467/16890027AP.18.017.10093In arid environments, protist diversity is higher in soil covered by vegetation than in bare soil and is also likely to vary in line with the marked seasonal patterns; however, these patterns have not been explored in detail in arid zones. Herein, we used culture – and morphological-based approaches to describe patterns of amoeboid protist diversity in vegetated and bare soil areas from the intertropical desert of Tehuacán, Mexico, during dry and wet seasons. Overall, 27 protist species belonging to Amoebozoa, Discoba and Rhizaria were retrieved using culture-dependent methods. Among the soil protist groups found, Discoba (principally represented by Heterolobosea) was always the most prevalent taxa. Protist diversity was different between soil with vegetation and bare soil, principally during the dry season. Moreover, the electrical conductivity and pH of the soil were correlated with the protist species during the wet season. Our results support the hypothesis that soil protist diversity patterns exhibit a seasonal variation between dry and wet seasons. This seasonal variation likely relies on water availability, although the role of other environmental factors cannot be completely ruled out. In addition, the soils with vegetation could be a refuge for the amoeboid protists during the harsh soil conditions of dry seasons.
Kristina I. Prokina, Dmitry G. Zagumyonnyi, Denis V. Tikhonenkov
Acta Protozoologica, Volume 57, Issue 4, 2018, pp. 245 - 266
https://doi.org/10.4467/16890027AP.18.018.10094Species diversity of centrohelid heliozoans in different types of freshwater bodies (forest lakes, floodplain lakes, sphagnum bogs, and river) in the Middle Russian forest-steppe was studied. The morphology of cell coverings (scales and spicules) were observed using scanning and transmission electron microscopy. A total of 20 species of centrohelid heliozoans from five families (Acanthocystidae, Pterocystidae, Raphidiophryidae, Raphidocystidae, and Choanocystidae) and six genera (Acanthocystis, Raineriophrys, Pterocystis, Raphidiophrys, Raphidocystis, and Choanocystis) as well as unidentified Centrohelea species and a Heterophrys-like organism were found. Morphological descriptions and electron micrographs are provided. The most common species were Acanthocystis nichollsi, Raphidiophrys capitata, and a Heterophrys-like organism. The highest species diversity was observed in terrace forest lakes, whereas the lowest was seen in sphagnum bogs. Four species (Acanthocystis costata, A. elenazhivotovae, A. mikrjukovii, and A. spinosa) were found for the first time since their original description. Three species (Acanthocystis spinosa, Raphidiophrys capitata, and Pterocystis pulchra) are new records for Russia. The distribution of the observed morphospecies confirms the cosmopolitanism of many centrohelids and highlights the importance of the type of water body and microbiotope in forming the species composition. The obtained data on the morphology of studied scales supplements our knowledge of the intraspecific variability of centrohelid heliozoans.
Hoan Q. Trana, Yuri A. Mazei
Acta Protozoologica, Volume 57, Issue 4, 2018, pp. 215 - 229
https://doi.org/10.4467/16890027AP.18.016.10092Testate amoebae in Vietnam are still poorly investigated. We studied species composition of testate amoebae in 47 waterbodies of South Vietnam provinces including natural lakes, reservoirs, wetlands, rivers, and irrigation channels. A total of 109 species and subspecies belonging to 16 genera, 9 families were identified from 191 samples. Thirty-five species and subspecies were observed in Vietnam for the first time. New species Difflugia vietnamica sp. nov. is described. The most species-rich genera are Difflugia (46 taxa), Arcella (25) and Centropyxis (14). Centropyxis aculeata was the most common species (observed in 68.1% samples). Centropyxis aerophila sphagniсola, Arcella discoides, Difflugia schurmanni and Lesquereusia modesta were characterised by a frequency of occurrence >20%. Other species were rarer. The species accumulation curve based on the entire dataset of this work was unsaturated and well fitted by equation S = 19.46N0.33. Species richness per sample in natural lakes and wetlands were significantly higher than that of rivers (p < 0.001). The result of the Spearman rank test shows weak or statistically insignificant relationships between species richness and water temperature, pH, dissolved oxygen, and electrical conductivity.
Horacio Pérez-Juárez, Angélica Serrano-Vázquez, Enrique Lara, Cecilia Ximénez, Héctor Godínez-Alvarez, Salvador Rodríguez-Zaragoza, Luis E. Eguiarte, Mayra M. Hernández Moreno, Leonardo David Fernández, Leonardo D. Fernández , Liliana Rojas-Velázquez, Patricia Morán, Mariela Castillo, Víctor M. Rivera Aguilar
Acta Protozoologica, Volume 57, Issue 4, 2018, pp. 231 - 242
https://doi.org/10.4467/16890027AP.18.017.10093In arid environments, protist diversity is higher in soil covered by vegetation than in bare soil and is also likely to vary in line with the marked seasonal patterns; however, these patterns have not been explored in detail in arid zones. Herein, we used culture – and morphological-based approaches to describe patterns of amoeboid protist diversity in vegetated and bare soil areas from the intertropical desert of Tehuacán, Mexico, during dry and wet seasons. Overall, 27 protist species belonging to Amoebozoa, Discoba and Rhizaria were retrieved using culture-dependent methods. Among the soil protist groups found, Discoba (principally represented by Heterolobosea) was always the most prevalent taxa. Protist diversity was different between soil with vegetation and bare soil, principally during the dry season. Moreover, the electrical conductivity and pH of the soil were correlated with the protist species during the wet season. Our results support the hypothesis that soil protist diversity patterns exhibit a seasonal variation between dry and wet seasons. This seasonal variation likely relies on water availability, although the role of other environmental factors cannot be completely ruled out. In addition, the soils with vegetation could be a refuge for the amoeboid protists during the harsh soil conditions of dry seasons.
Kristina I. Prokina, Dmitry G. Zagumyonnyi, Denis V. Tikhonenkov
Acta Protozoologica, Volume 57, Issue 4, 2018, pp. 245 - 266
https://doi.org/10.4467/16890027AP.18.018.10094Species diversity of centrohelid heliozoans in different types of freshwater bodies (forest lakes, floodplain lakes, sphagnum bogs, and river) in the Middle Russian forest-steppe was studied. The morphology of cell coverings (scales and spicules) were observed using scanning and transmission electron microscopy. A total of 20 species of centrohelid heliozoans from five families (Acanthocystidae, Pterocystidae, Raphidiophryidae, Raphidocystidae, and Choanocystidae) and six genera (Acanthocystis, Raineriophrys, Pterocystis, Raphidiophrys, Raphidocystis, and Choanocystis) as well as unidentified Centrohelea species and a Heterophrys-like organism were found. Morphological descriptions and electron micrographs are provided. The most common species were Acanthocystis nichollsi, Raphidiophrys capitata, and a Heterophrys-like organism. The highest species diversity was observed in terrace forest lakes, whereas the lowest was seen in sphagnum bogs. Four species (Acanthocystis costata, A. elenazhivotovae, A. mikrjukovii, and A. spinosa) were found for the first time since their original description. Three species (Acanthocystis spinosa, Raphidiophrys capitata, and Pterocystis pulchra) are new records for Russia. The distribution of the observed morphospecies confirms the cosmopolitanism of many centrohelids and highlights the importance of the type of water body and microbiotope in forming the species composition. The obtained data on the morphology of studied scales supplements our knowledge of the intraspecific variability of centrohelid heliozoans.
Publication date: 11.01.2019
Editor-in-Chief: Krzysztof Wiąckowski
Wen Song, Jiamei Li, Yaoyao Huang, Xiaozhong Hu, Weiwei Liu, Khaled A. S. Al-Rasheid, Miao Miao
Acta Protozoologica, Volume 57, Issue 3, 2018, pp. 153 - 167
https://doi.org/10.4467/16890027AP.18.013.10089As a follow-up part of our studies of the tropical ciliate fauna carried out in the last decade, we investigated the morphology and phylogeny of three choreotrich ciliates, viz, Parastrombidinopsis costalis sp. n., P. pelagica (Fauré-Fremiet, 1924) comb. n. and P. minima Tsai et al., 2008. The new species is characterized by its unique asymmetrical cell shape, 19–21 collar membranelles, one buccal membrane, and eight unevenly distributed somatic kineties.An improved diagnosis of P. pelagica(Fauré-Fremiet, 1924) comb. n.is given based on the original and current studies, the species is characterized by a large cell size, an elongate obconical cell shape, 31–36 collar membranelles and 13–15 somatic kineties. The species P. minimais redescribed based on a new population with some new features supplemented.SSU rRNA genes of both the new species and P. minima were sequenced and a phylogenetic review of related taxa obtained has been performed in order to reveal their systematic relationships. The monophyly of the genus Parastrombidinopsis is highly supported in our phylogenetic analyses.
Christian F. Bardele, Nicole Stockmann, Sabine Agatha
Acta Protozoologica, Volume 57, Issue 3, 2018, pp. 169 - 193
https://doi.org/10.4467/16890027AP.18.014.10090The first transmission and scanning electron microscopical studies in combination with freeze-fracture technology have disclosed some important morphological and ultrastructural features in the freshwater oligotrichid Limnostrombidium viride. (I) The dikinetids (paired basal bodies) of the girdle kinety have a club-shaped cilium associated only with each left basal body. The electron-dense (paraflagellar) body on one side of its “92+2”-axoneme and the regular array of intramembranous particles indicate a sensory, perhaps photoreceptor function of these club-shaped cilia. (II) The stichomonad endoral membrane is proximally covered by a cytoplasmic fold and distally by multiple membranous layers. Thus entirely covered, the endoral is probably no longer involved in food capture; none the less, its associated microtubules might stabilise the cytopharynx. (III) Instead of a contractile vacuole, a horizontal ring-canal with supposed osmoregulatory function occurs. (IV) The extrusive nature of the trichites is not only observed in electron micrographs, but the attachment sites of these organelles also display a rosette of “8+1”-particles in the P-face of freeze-fracture replicas typical for ciliate extrusomes. (V) The neoformation organelle, the subsurface tube in which stomatogenesis takes place, shows short basal bodies and normal axonemes about 1 μm long. It is accompanied by numerous membrane vesicles, which might provide membrane material for the outgrowing cilia.
Michael S. Gruber, Alexandra Mühlthaler, Sabine Agatha
Acta Protozoologica, Volume 57, Issue 3, 2018, pp. 195 - 214
https://doi.org/10.4467/16890027AP.18.015.10091Molecular phylogenies of Oligotrichea currently do not contain all genera and families and display topologies which are often incongruent with morphological findings. In ciliates, the somatic kinetids are rather conserved, i.e., their ultrastructures, particularly the fibrillar associates, often characterise the main groups, except for the choreotrichids. Four different kinetid types are found in protargolstained choreotrichids and used for reconstructing the taxon’s evolution (the “Kinetid Transformation Hypothesis”). Proof for this hypothesis requires transmission electron microscopic studies, which are very rare in the choreotrichids and oligotrichids. Such an approach provides insights into the ultrastructural variability of somatic kinetids in spirotrichs and may also detect apomorphies characterising certain choreotrichid families. In the model tintinnid Schmidingerella meunieri, the ultrastructure of the three kinetid types in the somatic ciliature is studied in cryofixed cells. The data support the “Kinetid Transformation Hypothesis” regarding tintinnids with a ventral kinety. This first detailed study on kinetids in tintinnids and choreotrichids in general reveals totally new kinetid types in ciliates: beyond the three common associates, they are characterised by two or three conspicuous microtubular ribbons extending on the kinetids’ left sides. These extraordinary ribbons form together with the overlapping postciliary ribbons a unique network in the cortex of the anterior cell portion. The evolutionary constrains which might have fostered the development of such structures are discussed for the Oligotrichea, the choreotrichids, and tintinnids as their first occurrence is currently uncertain. Additionally, the kinetids in tintinnids, aloricate choreotrichids, oligotrichids, hypotrichs, and euplotids are compared.
Wen Song, Jiamei Li, Yaoyao Huang, Xiaozhong Hu, Weiwei Liu, Khaled A. S. Al-Rasheid, Miao Miao
Acta Protozoologica, Volume 57, Issue 3, 2018, pp. 153 - 167
https://doi.org/10.4467/16890027AP.18.013.10089As a follow-up part of our studies of the tropical ciliate fauna carried out in the last decade, we investigated the morphology and phylogeny of three choreotrich ciliates, viz, Parastrombidinopsis costalis sp. n., P. pelagica (Fauré-Fremiet, 1924) comb. n. and P. minima Tsai et al., 2008. The new species is characterized by its unique asymmetrical cell shape, 19–21 collar membranelles, one buccal membrane, and eight unevenly distributed somatic kineties.An improved diagnosis of P. pelagica(Fauré-Fremiet, 1924) comb. n.is given based on the original and current studies, the species is characterized by a large cell size, an elongate obconical cell shape, 31–36 collar membranelles and 13–15 somatic kineties. The species P. minimais redescribed based on a new population with some new features supplemented.SSU rRNA genes of both the new species and P. minima were sequenced and a phylogenetic review of related taxa obtained has been performed in order to reveal their systematic relationships. The monophyly of the genus Parastrombidinopsis is highly supported in our phylogenetic analyses.
Christian F. Bardele, Nicole Stockmann, Sabine Agatha
Acta Protozoologica, Volume 57, Issue 3, 2018, pp. 169 - 193
https://doi.org/10.4467/16890027AP.18.014.10090The first transmission and scanning electron microscopical studies in combination with freeze-fracture technology have disclosed some important morphological and ultrastructural features in the freshwater oligotrichid Limnostrombidium viride. (I) The dikinetids (paired basal bodies) of the girdle kinety have a club-shaped cilium associated only with each left basal body. The electron-dense (paraflagellar) body on one side of its “92+2”-axoneme and the regular array of intramembranous particles indicate a sensory, perhaps photoreceptor function of these club-shaped cilia. (II) The stichomonad endoral membrane is proximally covered by a cytoplasmic fold and distally by multiple membranous layers. Thus entirely covered, the endoral is probably no longer involved in food capture; none the less, its associated microtubules might stabilise the cytopharynx. (III) Instead of a contractile vacuole, a horizontal ring-canal with supposed osmoregulatory function occurs. (IV) The extrusive nature of the trichites is not only observed in electron micrographs, but the attachment sites of these organelles also display a rosette of “8+1”-particles in the P-face of freeze-fracture replicas typical for ciliate extrusomes. (V) The neoformation organelle, the subsurface tube in which stomatogenesis takes place, shows short basal bodies and normal axonemes about 1 μm long. It is accompanied by numerous membrane vesicles, which might provide membrane material for the outgrowing cilia.
Michael S. Gruber, Alexandra Mühlthaler, Sabine Agatha
Acta Protozoologica, Volume 57, Issue 3, 2018, pp. 195 - 214
https://doi.org/10.4467/16890027AP.18.015.10091Molecular phylogenies of Oligotrichea currently do not contain all genera and families and display topologies which are often incongruent with morphological findings. In ciliates, the somatic kinetids are rather conserved, i.e., their ultrastructures, particularly the fibrillar associates, often characterise the main groups, except for the choreotrichids. Four different kinetid types are found in protargolstained choreotrichids and used for reconstructing the taxon’s evolution (the “Kinetid Transformation Hypothesis”). Proof for this hypothesis requires transmission electron microscopic studies, which are very rare in the choreotrichids and oligotrichids. Such an approach provides insights into the ultrastructural variability of somatic kinetids in spirotrichs and may also detect apomorphies characterising certain choreotrichid families. In the model tintinnid Schmidingerella meunieri, the ultrastructure of the three kinetid types in the somatic ciliature is studied in cryofixed cells. The data support the “Kinetid Transformation Hypothesis” regarding tintinnids with a ventral kinety. This first detailed study on kinetids in tintinnids and choreotrichids in general reveals totally new kinetid types in ciliates: beyond the three common associates, they are characterised by two or three conspicuous microtubular ribbons extending on the kinetids’ left sides. These extraordinary ribbons form together with the overlapping postciliary ribbons a unique network in the cortex of the anterior cell portion. The evolutionary constrains which might have fostered the development of such structures are discussed for the Oligotrichea, the choreotrichids, and tintinnids as their first occurrence is currently uncertain. Additionally, the kinetids in tintinnids, aloricate choreotrichids, oligotrichids, hypotrichs, and euplotids are compared.
Publication date: 06.06.2018
Editor-in-Chief: Krzysztof Wiąckowski
Yufan Deng, Xiaoteng Lu, Jingbao Li, Sang Ba, Thiago da Silva Paiva
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 69 - 78
https://doi.org/10.4467/16890027AP.18.007.8981In this study, morphology of a Brazilian population of Eschaneustyla terricola Foissner, 1982 and a Chinese population of E. lugeri Foissner, Agatha & Berger, 2002 were studied based on living observation and protargol impregnation. Several stages of morphogenesis in E. lugeri were reported and the most remarkable features are characterized as follows: (1) partly renewal of adoral zone of membranelles in the proter and the parental midventral cirri do not join the construction of the opisthe’s oral primordium; (2) three or four buccal cirri each develop from one frontoventral cirral anlage and undulating membranes anlage generates two frontal cirri; (3) frontoventral cirral anlagen n and n-1 develop de novo and in the frontoterminal cirral row, respectively; (4) intrakinetal development of marginal and dorsal kineties anlagen; (5) fusion of macronuclear nodules into a single mass.
Yang Bai, Song Li, Yuan Li, Miao Miao, Xiaozhong Hu
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 79 - 94
https://doi.org/10.4467/16890027AP.18.008.8982A Chinese population of Oxytricha nauplia Berger et Foissner, 1987 was recently discovered from the surface soil in the Kuisu Valley, Huhhot, China. Its morphology corresponds well with that of the original population in the body size and shape, the absence of cortical granules, two macronuclear nodules and two micronuclei. Both morphogenesis during binary fission and small subunit of ribosomal gene (SSU rDNA) of the species were first investigated. Though earlier dividers are unavailable for this species, morphogenesis almost proceeds as in congeners by given stages. The SSU rDNA sequence of O. nauplia is 1728 bp long and has a DNA G+C content of 45.72%. Phylogenetic analyses revealed that Oxytricha nauplia grouped with O. paragranulifera first with high support, and then clustered into a subclade including Onychodromopsis flexilis, Paroxytricha ottowi, Paroxytricha longigranulosa and Rigidothrix goiseri, which branched off most congeners, but clustered into the Oxytrichidae clade.
Zhishuai Qu, René Groben, Viggó Marteinsson, Sabine Agatha, Sabine Filker, Thorsten Stoeck
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 95 - 106
https://doi.org/10.4467/16890027AP.18.009.8983We 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.
Yingzhi Ning, Yongqiang Yang, Tengteng Zhang, Lingyun Chen, Khaled A. S. Al-Rasheid, Zhenzhen Yi
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 107 - 122
https://doi.org/10.4467/16890027AP.18.010.8984The morphology and morphogenesis of two populations of the soil hypotrichous ciliate, Parakahliella macrostoma (Foissner, 1982) Berger et al. 1985, isolated from northwest China, were investigated based on specimens examined in vivo and stained with protargol. Our populations resemble the original one in terms of their live characters and cirral pattern. The main events during binary fission are as follows: (1) the parental adoral zone of membranelles is retained completely by the proter; (2) both in the proter and in the opisthe five frontal-ventral cirral anlagen are recognizable; (3) the marginal rows and dorsal kineties develop intrakinetally. In addition, the SSU rRNA gene was sequenced for the genus Parakahliella for the first time. Molecular phylogenetic analyses suggest that two populations of the genus Parakahliella cluster together and have a close relationship with species of Oxytrichidae.
Borong Lu, Daode Ji, Yalan Sheng, Weibo Song, Xiaozhong Hu, Xiangrui Chen, Khaled A. S. Al-Rasheid
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 123 - 143
https://doi.org/10.4467/16890027AP.18.011.8985Alma G. Islas-Ortega, Rogelio Aguilar-Aguilar, Paula S. Marcotegui , Sergio R. Martorelli, David Hernández-Mena, Gerardo Pérez-Ponce de León
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 145 - 151
https://doi.org/10.4467/16890027AP.18.012.8986Trichodina rectuncinata is one of the trichodinids most widely distributed in marine fish. This ciliate species has been recorded in more than 20 host species belonging to 17 fish families worldwide. Previous comparative studies based on morphometric data revealed considerable morphological variation among specimens from different populations of T. rectuncinata. In this study, we conducted a morphometric-molecular analysis of three populations of T. rectuncinata to evaluate potential differences among 18S rRNA sequences, in relation to morphological variations. Smears were obtained from marine fishes in three localities along the Pacific coast of Mexico. Based on the shape of denticles, we found four different morphotypes for T. rectuncinata. This morphological variability does not correspond with the genetic divergence, suggesting that all analyzed populations belong to the same species. Further analyses using more variable markers are necessary to corroborate the findings of our study.
Yufan Deng, Xiaoteng Lu, Jingbao Li, Sang Ba, Thiago da Silva Paiva
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 69 - 78
https://doi.org/10.4467/16890027AP.18.007.8981In this study, morphology of a Brazilian population of Eschaneustyla terricola Foissner, 1982 and a Chinese population of E. lugeri Foissner, Agatha & Berger, 2002 were studied based on living observation and protargol impregnation. Several stages of morphogenesis in E. lugeri were reported and the most remarkable features are characterized as follows: (1) partly renewal of adoral zone of membranelles in the proter and the parental midventral cirri do not join the construction of the opisthe’s oral primordium; (2) three or four buccal cirri each develop from one frontoventral cirral anlage and undulating membranes anlage generates two frontal cirri; (3) frontoventral cirral anlagen n and n-1 develop de novo and in the frontoterminal cirral row, respectively; (4) intrakinetal development of marginal and dorsal kineties anlagen; (5) fusion of macronuclear nodules into a single mass.
Yang Bai, Song Li, Yuan Li, Miao Miao, Xiaozhong Hu
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 79 - 94
https://doi.org/10.4467/16890027AP.18.008.8982A Chinese population of Oxytricha nauplia Berger et Foissner, 1987 was recently discovered from the surface soil in the Kuisu Valley, Huhhot, China. Its morphology corresponds well with that of the original population in the body size and shape, the absence of cortical granules, two macronuclear nodules and two micronuclei. Both morphogenesis during binary fission and small subunit of ribosomal gene (SSU rDNA) of the species were first investigated. Though earlier dividers are unavailable for this species, morphogenesis almost proceeds as in congeners by given stages. The SSU rDNA sequence of O. nauplia is 1728 bp long and has a DNA G+C content of 45.72%. Phylogenetic analyses revealed that Oxytricha nauplia grouped with O. paragranulifera first with high support, and then clustered into a subclade including Onychodromopsis flexilis, Paroxytricha ottowi, Paroxytricha longigranulosa and Rigidothrix goiseri, which branched off most congeners, but clustered into the Oxytrichidae clade.
Zhishuai Qu, René Groben, Viggó Marteinsson, Sabine Agatha, Sabine Filker, Thorsten Stoeck
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 95 - 106
https://doi.org/10.4467/16890027AP.18.009.8983We 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.
Yingzhi Ning, Yongqiang Yang, Tengteng Zhang, Lingyun Chen, Khaled A. S. Al-Rasheid, Zhenzhen Yi
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 107 - 122
https://doi.org/10.4467/16890027AP.18.010.8984The morphology and morphogenesis of two populations of the soil hypotrichous ciliate, Parakahliella macrostoma (Foissner, 1982) Berger et al. 1985, isolated from northwest China, were investigated based on specimens examined in vivo and stained with protargol. Our populations resemble the original one in terms of their live characters and cirral pattern. The main events during binary fission are as follows: (1) the parental adoral zone of membranelles is retained completely by the proter; (2) both in the proter and in the opisthe five frontal-ventral cirral anlagen are recognizable; (3) the marginal rows and dorsal kineties develop intrakinetally. In addition, the SSU rRNA gene was sequenced for the genus Parakahliella for the first time. Molecular phylogenetic analyses suggest that two populations of the genus Parakahliella cluster together and have a close relationship with species of Oxytrichidae.
Borong Lu, Daode Ji, Yalan Sheng, Weibo Song, Xiaozhong Hu, Xiangrui Chen, Khaled A. S. Al-Rasheid
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 123 - 143
https://doi.org/10.4467/16890027AP.18.011.8985Alma G. Islas-Ortega, Rogelio Aguilar-Aguilar, Paula S. Marcotegui , Sergio R. Martorelli, David Hernández-Mena, Gerardo Pérez-Ponce de León
Acta Protozoologica, Volume 57, Issue 2, 2018, pp. 145 - 151
https://doi.org/10.4467/16890027AP.18.012.8986Trichodina rectuncinata is one of the trichodinids most widely distributed in marine fish. This ciliate species has been recorded in more than 20 host species belonging to 17 fish families worldwide. Previous comparative studies based on morphometric data revealed considerable morphological variation among specimens from different populations of T. rectuncinata. In this study, we conducted a morphometric-molecular analysis of three populations of T. rectuncinata to evaluate potential differences among 18S rRNA sequences, in relation to morphological variations. Smears were obtained from marine fishes in three localities along the Pacific coast of Mexico. Based on the shape of denticles, we found four different morphotypes for T. rectuncinata. This morphological variability does not correspond with the genetic divergence, suggesting that all analyzed populations belong to the same species. Further analyses using more variable markers are necessary to corroborate the findings of our study.
Publication date: 06.04.2018
Editor-in-Chief: Krzysztof Wiąckowski
O. Roger Anderson
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 1 - 28
https://doi.org/10.4467/16890027AP.18.001.8395This is a review of over 400 published research papers on free-living, non-testate amoebae during the approximate last half century (1965-2017) particularly focusing on three topics: Biogeography, Ecology, and Physiology. These topics were identified because of the substantial attention given to them during the course of the last half century, and due to their potential importance in issues of local and global expanse, such as: aquatic and terrestrial stability of habitats, ecosystem processes, biogeochemistry and climate change, and the role of eukaryotic microbes generally in ecosystem services. Moreover, there are close epistemological and thematic ties among the three topics, making a synthesis of the published research more systematic and productive. The number of reviewed publications for each of the three individual topics is presented to illustrate the trends in publication frequencies during the historical period of analysis. Overall, the number of total publications reviewed varied somewhat between 1965 and early 2000 (generally less than 10 per year), but increased to well over 10 per year after 2000. The number of Biogeography and Ecology studies identified in the online citations increased substantially after the mid 1990s, while studies focusing on Physiology were relatively more abundant in the first decade (1965-1974) and less were identified in the 1985 to 2004 period. Citations to the literature are listed in tables for each of the three topics for convenience in retrieving references to specific aspects, and representative examples of the cited research in the tables are reviewed in the text under subheads dedicated to each of the three topics. Biogeographic studies largely focused on the geographic distribution and localized patterns of occurrence of amoebae, with more recent studies incorporating more attention to likely correlates with environmental and biotic factors in the distribution and community composition of amoebae. Ecological studies reviewed in the later decades tended to focus more on community dynamics, the effects of environmental variables on communities (including climate-related topics), a trend toward more physiological ecology studies, combined field-based and experimental studies, and incorporation of newer methodologies such as molecular genetics. In general, physiology studies in the first decades of the review tended to focus on topics of cell physiology such as basic biochemistry, enzyme assays, mechanisms of cell division and development, encystment, and motility. Later studies examined broader topics such as osmoregulation, nutrition, fine structure evidence of cellular changes during the life cycle (including encystment and excystment), and issues related to asexual and sexual reproduction, with increasing substantial evidence of evolutionary patterns and phylogenetics based on molecular evidence. A final section on Conclusions and Recommendations summarizes the findings and presents some potentially productive approaches to future research studies on Amoebozoa within the three designated topics of analysis.
Anna Glotova, Natalya Bondarenko, Alexey Smirnov
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 29 - 42
https://doi.org/10.4467/16890027AP.18.002.8396Piotr Solarczyk, Agnieszka Wojtkowiak-Giera, Marcin Hołysz, Anna Słodkowicz-Kowalska, Paweł P. Jagodziński, Krzysztof Stojecki, Anna Rocka, Anna C. Majewska, Łukasz Skrzypczak
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 43 - 48
https://doi.org/10.4467/16890027AP.18.003.8397iardia duodenalisis one of the six Giardia species and itis the most common, cosmopolitan flagellate that infects humans and many species of animals.This species exhibits considerable genetic diversity; to date, eight assemblages (A–H) have been defined. These assemblages differ in host specificity: assemblages A and B have beenfound in both humans and in many animal species. Mixed infections with Giardia (A and B) assemblages have been reported in humans and in animals. Many molecular techniques are effective and rapid for the detection of G. duodenalis and also forthe determination of genetic variability of isolates in clinical and environmental samples. In this context, the aim of this study was to design new assemblage-specific primers for rapid detection and identification ofG. duodenalis assemblages A and B and both of these assemblages simultaneously using quantitative real-time polymerase chain reaction (qPCR). Fragments of glutamate dehydrogenase and triose phosphate isomerase were used as targets in the design of primers.
In conclusion, the use of G. duodenalis assemblage-specific primers designed in this study allows quick identification of human infectious G. duodenalis assemblages A and B as well as mixed AB assemblages in a sample without further sequencing of the amplification products, which reduces the cost of study and the waiting time for the results.
Inna V Grushevaya, Anastasia N. Ignatieva, Svetlana M. Malysh, Igor V. Senderskiy , Ivan V. Zubarev, Anastasia G. Kononchuk
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 49 - 52
https://doi.org/10.4467/16890027AP.18.004.8398Microsporidia infection rate in Ostrinia nubilalis larvae collected in Russia in 2011-2016 ranged from 0 to 16 %. Totally, among 262 examined insects, there were as many as 13 infected specimens, resulting in average prevalence of 5 % over the period indicated. In all positive samples but one diplokaryotic spores 4 um long were observed corresponding to diagnosis of Nosema pyrausta. Nevertheless, in one case (i.e. 0.4 %) the infected larva contained monokaryotic spores about 2 um long. After experimental infection of a substitute host Ostrinia furnacalis with monokaryotic spores only Nosema-like spores were observed in laboratory assays. Ribosomal RNA and RPB1 gene portions were 100 % identical in samples of both mono- and diplokaryotic spores. This observation shows that Nosema pyrausta can form uninucleate spores under yet to be described conditions in nature and that molecular genetic analysis is essential for correct species identification.
Milena Svobodová , Jana Rádrová
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 53 - 59
https://doi.org/10.4467/16890027AP.18.005.8399Phlebotomine sandflies were tested as potential vectors of avian trypanosomes (Kinetoplastea: Trypanosomatidae). Lutzomyia longipalpis and Phlebotomus arabicus took bloodmeals with cultured Trypanosoma avium parasites; mature infections with stages transmissible to canaries (Serinus canaria) developed in the sandflies. The infection rates ranged between 66 and 89%, with heavy infections in 24 - 78% fed females. L. longipalpis that fed on infected birds were also infected, and some developed mature infections (37 and 19%, resp). On the contrary, Lutzomyia longipalpis and Phlebotomus arabicus were not susceptible to infection with trypanosomes from T. bennetti clade. Our results, together with the previous findings of naturally infected L. caballeroi, suggest that sandflies could serve as vectors of avian trypanosomes from the T. avium clade.
Franciane Cedrola, Priscila Fregulia, M. D'Agosto, Roberto Júnio Pedroso Dias
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 61 - 67
https://doi.org/10.4467/16890027AP.18.006.8400In our study, we aimed to identify and quantify the intestinal ciliates in a Brazilian capybara and to compare the obtained data with previous studies on the capybara ciliate community in other geographic locations within the American continent. We identified 20 species belonging to four families and ten genera. This is the first study on intestinal ciliates in Brazilian capybara since the last reports for the country in the 1960s. Among the identified species, Anacharon gracilis, A. lepturus, Cycloposthium bursa, Monoposthium cynodontum, Ogimotopsis pumila, Paracunhamunizia calocoma, Protohallia nana and Uropogon urai were recorded for the first time in Brazil, and the giant ciliate Muniziella cunhai was observed for the second time in a symbiotic association with capybaras in the country. The present study highlighted the importance of knowing the gastrointestinal ciliate community associated with wild hosts in order to better understand their geographic distribution and host specificity.
O. Roger Anderson
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 1 - 28
https://doi.org/10.4467/16890027AP.18.001.8395This is a review of over 400 published research papers on free-living, non-testate amoebae during the approximate last half century (1965-2017) particularly focusing on three topics: Biogeography, Ecology, and Physiology. These topics were identified because of the substantial attention given to them during the course of the last half century, and due to their potential importance in issues of local and global expanse, such as: aquatic and terrestrial stability of habitats, ecosystem processes, biogeochemistry and climate change, and the role of eukaryotic microbes generally in ecosystem services. Moreover, there are close epistemological and thematic ties among the three topics, making a synthesis of the published research more systematic and productive. The number of reviewed publications for each of the three individual topics is presented to illustrate the trends in publication frequencies during the historical period of analysis. Overall, the number of total publications reviewed varied somewhat between 1965 and early 2000 (generally less than 10 per year), but increased to well over 10 per year after 2000. The number of Biogeography and Ecology studies identified in the online citations increased substantially after the mid 1990s, while studies focusing on Physiology were relatively more abundant in the first decade (1965-1974) and less were identified in the 1985 to 2004 period. Citations to the literature are listed in tables for each of the three topics for convenience in retrieving references to specific aspects, and representative examples of the cited research in the tables are reviewed in the text under subheads dedicated to each of the three topics. Biogeographic studies largely focused on the geographic distribution and localized patterns of occurrence of amoebae, with more recent studies incorporating more attention to likely correlates with environmental and biotic factors in the distribution and community composition of amoebae. Ecological studies reviewed in the later decades tended to focus more on community dynamics, the effects of environmental variables on communities (including climate-related topics), a trend toward more physiological ecology studies, combined field-based and experimental studies, and incorporation of newer methodologies such as molecular genetics. In general, physiology studies in the first decades of the review tended to focus on topics of cell physiology such as basic biochemistry, enzyme assays, mechanisms of cell division and development, encystment, and motility. Later studies examined broader topics such as osmoregulation, nutrition, fine structure evidence of cellular changes during the life cycle (including encystment and excystment), and issues related to asexual and sexual reproduction, with increasing substantial evidence of evolutionary patterns and phylogenetics based on molecular evidence. A final section on Conclusions and Recommendations summarizes the findings and presents some potentially productive approaches to future research studies on Amoebozoa within the three designated topics of analysis.
Anna Glotova, Natalya Bondarenko, Alexey Smirnov
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 29 - 42
https://doi.org/10.4467/16890027AP.18.002.8396Piotr Solarczyk, Agnieszka Wojtkowiak-Giera, Marcin Hołysz, Anna Słodkowicz-Kowalska, Paweł P. Jagodziński, Krzysztof Stojecki, Anna Rocka, Anna C. Majewska, Łukasz Skrzypczak
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 43 - 48
https://doi.org/10.4467/16890027AP.18.003.8397iardia duodenalisis one of the six Giardia species and itis the most common, cosmopolitan flagellate that infects humans and many species of animals.This species exhibits considerable genetic diversity; to date, eight assemblages (A–H) have been defined. These assemblages differ in host specificity: assemblages A and B have beenfound in both humans and in many animal species. Mixed infections with Giardia (A and B) assemblages have been reported in humans and in animals. Many molecular techniques are effective and rapid for the detection of G. duodenalis and also forthe determination of genetic variability of isolates in clinical and environmental samples. In this context, the aim of this study was to design new assemblage-specific primers for rapid detection and identification ofG. duodenalis assemblages A and B and both of these assemblages simultaneously using quantitative real-time polymerase chain reaction (qPCR). Fragments of glutamate dehydrogenase and triose phosphate isomerase were used as targets in the design of primers.
In conclusion, the use of G. duodenalis assemblage-specific primers designed in this study allows quick identification of human infectious G. duodenalis assemblages A and B as well as mixed AB assemblages in a sample without further sequencing of the amplification products, which reduces the cost of study and the waiting time for the results.
Inna V Grushevaya, Anastasia N. Ignatieva, Svetlana M. Malysh, Igor V. Senderskiy , Ivan V. Zubarev, Anastasia G. Kononchuk
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 49 - 52
https://doi.org/10.4467/16890027AP.18.004.8398Microsporidia infection rate in Ostrinia nubilalis larvae collected in Russia in 2011-2016 ranged from 0 to 16 %. Totally, among 262 examined insects, there were as many as 13 infected specimens, resulting in average prevalence of 5 % over the period indicated. In all positive samples but one diplokaryotic spores 4 um long were observed corresponding to diagnosis of Nosema pyrausta. Nevertheless, in one case (i.e. 0.4 %) the infected larva contained monokaryotic spores about 2 um long. After experimental infection of a substitute host Ostrinia furnacalis with monokaryotic spores only Nosema-like spores were observed in laboratory assays. Ribosomal RNA and RPB1 gene portions were 100 % identical in samples of both mono- and diplokaryotic spores. This observation shows that Nosema pyrausta can form uninucleate spores under yet to be described conditions in nature and that molecular genetic analysis is essential for correct species identification.
Milena Svobodová , Jana Rádrová
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 53 - 59
https://doi.org/10.4467/16890027AP.18.005.8399Phlebotomine sandflies were tested as potential vectors of avian trypanosomes (Kinetoplastea: Trypanosomatidae). Lutzomyia longipalpis and Phlebotomus arabicus took bloodmeals with cultured Trypanosoma avium parasites; mature infections with stages transmissible to canaries (Serinus canaria) developed in the sandflies. The infection rates ranged between 66 and 89%, with heavy infections in 24 - 78% fed females. L. longipalpis that fed on infected birds were also infected, and some developed mature infections (37 and 19%, resp). On the contrary, Lutzomyia longipalpis and Phlebotomus arabicus were not susceptible to infection with trypanosomes from T. bennetti clade. Our results, together with the previous findings of naturally infected L. caballeroi, suggest that sandflies could serve as vectors of avian trypanosomes from the T. avium clade.
Franciane Cedrola, Priscila Fregulia, M. D'Agosto, Roberto Júnio Pedroso Dias
Acta Protozoologica, Volume 57, Issue 1, 2018, pp. 61 - 67
https://doi.org/10.4467/16890027AP.18.006.8400In our study, we aimed to identify and quantify the intestinal ciliates in a Brazilian capybara and to compare the obtained data with previous studies on the capybara ciliate community in other geographic locations within the American continent. We identified 20 species belonging to four families and ten genera. This is the first study on intestinal ciliates in Brazilian capybara since the last reports for the country in the 1960s. Among the identified species, Anacharon gracilis, A. lepturus, Cycloposthium bursa, Monoposthium cynodontum, Ogimotopsis pumila, Paracunhamunizia calocoma, Protohallia nana and Uropogon urai were recorded for the first time in Brazil, and the giant ciliate Muniziella cunhai was observed for the second time in a symbiotic association with capybaras in the country. The present study highlighted the importance of knowing the gastrointestinal ciliate community associated with wild hosts in order to better understand their geographic distribution and host specificity.
Publication date: 14.12.2017
Editor-in-Chief: Krzysztof Wiąckowski
Lingyun Chen, Xiaolu Zhao, Hamed A. El-Serehy, Jie Huang, John C. Clamp
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 221 - 233
https://doi.org/10.4467/16890027AP.17.020.7822Tachysoma pellionellum Stokes, 1887, a freshwater ciliate isolated from Stone Mountain State Park, North Carolina, was studied in vivo and after staining with protargol. The population was characterized mainly by having the typical 18 frontal-ventral-transverse cirri; posterior ends of left and right marginal rows not confluent; five dorsal kineties and one dorsomarginal kinety; two macronuclear nodules near left cell margin with one or two micronuclei between them; contractile vacuole located at mid-body near left margin. Morphogenesis is characterized as follows: (1) in the proter, the parental adoral zone of membranelles is retained completely; (2) 18 frontal-ventral-transverse cirri are derived from the anlage of the undulating membrane and the five streaks of the frontal-ventral-transverse anlagen; (3) marginal rows develop intrakinetally; (4) anlagen of dorsal kineties 1, 2 and 4 develop in the parental structure and anlagen of dorsal kineties 2 and 4 fragment in the posterior region forming anlagen of dorsal kineties 3 and 5; (5) only one dorsomarginal kinety formed; (6) the two macronuclear nodules fuse into a single mass, which then divides. Phylogenetic analyses based on sequences of the gene coding for SSU RNA revealed a close relationship between T. pellionellum and the Oxytricha clade, both of which grouped with Kleinstyla dorsicirrata and Heterourosomoida lanceolata.
Eleni Gentekaki, Chitchai Chantangsi
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 235 - 243
https://doi.org/10.4467/16890027AP.17.021.7823Opaline is an unusual group of protists, characterized by the presence of flagella covering their whole body. They reside in the intestinal tracts of various animals, most notably amphibians. While there is a wealth of data regarding the morphological features of opalines, molecular data are extremely sparse. Consequently, the extent of diversity of this understudied group remains unknown. Here, we examine opalines from the intestinal tract of the amphibian Hoplobatrachus rugulosus in Thailand. We provide micrographs obtained from light and scanning electron microscopy of various opalinid morphotypes. Furthermore, we enrich the database of opaline sequences by providing new molecular data of the small subunit ribosomal DNA gene of these species. In our phylogenetic analyses, the newly derived sequences form a cluster sister to Protoopalina.
Liesl L. van As, Linda Basson, Jo Van As
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 245 - 254
https://doi.org/10.4467/16890027AP.17.022.7824Members of the Urceolariidae Dujardin, 1941 have been found associated with a wide variety of invertebrate hosts from freshwater and marine habitats. Five species have been described from molluscan hosts from Europe and America. This paper deals with an urceolariid (Leiotrocha Fabre-Domergue, 1888) collected from the gills of Cellana radiata capensis (Gmelin, 1791) and Scutellastra exusta (Reeve, 1854) from the east coast of South Africa, as well as Patella depressa Pennant, 1777 and Cymbula safiana (Lamarck, 1891) from the bulge (west coast) of Africa. A higher prevalence was found on C. radiata capensis (89%) and P. depressa (72%) compared to the other two hosts. The urceolariid collected from the African limpets was identified as L. patellae (Cuénot, 1891). This is the first record of an urceolariid from any African hosts, including representatives of the Mollusca. Five urceolariid species were identified and described from gastropods, i.e. L. patellae Cuénot, 1891,U. karyolobia Hirshfield, 1949, U. cellanae Suzuki, 1950, U. viridis Richards, 1971 and U. parakorschelti Irwin, Sabetrasekh and Lynn, 2017. Motivation is provided why U. cellanae and U. viridis should be reallocated to the genus Leiotrocha, and U. karyolobia not. The taxonomic validity of the recent description of U. parakorschelti from limpets is commented on.
Ľubomír Rajter, Peter Vďačný
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 255 - 281
https://doi.org/10.4467/16890027AP.17.023.7825We investigated interrelationships between four free-living litostomatean lineages, using 18S rRNA gene and ITS region sequences as well as the secondary structure of the ITS2 molecules. Our phylogenetic analyses confirmed the deep split of free-living litostomateans into Rhynchostomatia and Haptoria represented here by Haptorida, Pleurostomatida, and Spathidiida. This bifurcation is also corroborated by the signature of the rhynchostomatian and haptorian ITS2 molecules. Specifically, the consensus stems of helices II and III are longer by one base pair in Rhynchostomatia, while the terminal loops of both helices are longer by one or two nucleotide/-s in Haptoria. A close relationship of Pleurostomatida and Haptorida is favored by quartet likelihood-mapping and supported by a 5’-AG vs. CU-3’ motif in the variable part of helix II and by two morphological apomorphies, i.e., meridionally extending somatic kineties and a non-three-rowed dorsal brush. Although monophyletic origin of Spathidiida is poorly supported in phylogenetic trees, the unique motif 5’-GA vs. UC-3’ present in the consensus helix II stem could be an important molecular synapomorphy of spathidiids, apart from the ancestrally anteriorly curved somatic kineties and the three-rowed dorsal brush. The peculiar family Pseudoholophryidae has very likely found its phylogenetic home among spathidiids, as an early branching lineage.
Mustafa Yaman
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 283 - 288
https://doi.org/10.4467/16890027AP.17.024.7826Chrysomela populi L. (Coleoptera; Chrysomelidae) is one of the most serious pests affecting poplars. Chemical control is the most widely known suppressive method against this pest. This method is not acceptable in urban forests because of their proximity to people. Entomopathogenic organisms are environmentally friendly control agents and suppress the pest populations under natural conditions. In the present study, the occurrence and distribution ofanew entomopathogenic protist,aneogregarine, Ophryocystis anatoliensis (Apicomplexa) in C. populi populations andamember of the family Chrysomelidae is presented for the first time. In total, 90 of 2185 C.populiadults and larvae collected from 16 localities during three years (from 2013 to 2015) were found to be infected by this pathogen. Neogregarine infection was observed in 14 of 16 investigated C. populi populations. The infection was variable between the populations and years. These results confirm that the neogregarine pathogen hasahigh dispersal potential through the C. populi populations and can be an effective natural biological suppressing factor on the pest populations.
Jing Li, Kun Yang, Feizhou Chen, Wenxuan Lu, Ting Fang, Xiuxia Zhao, Haiyang Li, Kai Cui
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 289 - 301
https://doi.org/10.4467/16890027AP.17.025.7827Direct and indirect effects of crustacean zooplankton (cladocerans and copepods) are important regulators of ciliate communities, especially in eutrophic systems. However, it is not clear whether pseudodiaptomids (e.g., Schmackeria), one of the dominant calanoid copepods in Chinese lakes, effectively impacts natural ciliate communities. The impacts of small-bodied cladocerans (e.g., Bosmina) on ciliates are also controversial.
We performed an incubation experiment using winter lake water from Lake Chaohu to assess the structuring effects that crustacean zooplankton have on natural ciliate populations. The presence and absence of cladocerans (Bosmina sp.) and copepods (Schmackeria inopinus) were alternated in four treatments.
Both Bosmina sp. and Schmackeria inopinus had substantial impacts on ciliate abundance, biomass, and community structure. The response of ciliates was different in the presence of Bosmina sp. compared with Schmackeria inopinus and varied among categories such as the ciliate population, relative body size and functional feeding group. Our results also highlight the importance of interference and exploitative competition among metazooplankton groups.
Xinlu Shi, Guijie Liu, Chundi Wang, Xiaozhong Hu
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 303 - 315
https://doi.org/10.4467/16890027AP.17.026.7828A brackish water euplotid ciliate, Uronychia xinjiangensis n. sp., was discovered in a ditch in Yuli County, Xinjiang, China. Its morphology, ciliature and morphogenesis were investigated based on specimens examined in vivo and following protargol staining. The new species is characterized by the posterior part of the adoral zone composed of three membranelles, which has never been seen in all other known congeners. Other morphologic features include: (i) body oval-shaped, with conspicuous right anterior spur-like protrusion;
(ii)size in vivo 60–90 × 40–68 μm; (iii) two macronuclear nodules; (iv) four frontal, two ventral, five transverse, three left marginal and three caudal cirri. Its morphogenesis proceeds in a usual way, except that the oral primordium forms only three proximal membranelles rather than four proximal membranelles within congeners. The small subunit rRNA gene of the new species (GenBank accession number: KX147287) comprises 1723 bp and 44.63% GC content, and differs by 0.12–1.81% from those of congeners. Phylogenetic analyses based on SSU rRNA gene sequence data reveal that Uronychia xinjiangensis n. sp. clusters with other Uronychia species with full support, which supports the monophyly of the genus Uronychia Stein, 1859.
Tania Tanveer, Abdul Hameed, Abdul-Aziz A. Bin-Dukhyil, Mohammed Alaidarous, Abdul Matin
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 317 - 322
https://doi.org/10.4467/16890027AP.17.027.7829Naegleria is well recognized for primary amoebic meningoencephalitis which always results into death. To date there is not a single report demonstrating molecular identification of Naegleria from water resources of Pakistan thus the aim of the proposed study.Here, in total 135 various water samples (like domestic tap water, municipal water, sea water, well water, tube well water, canal water, boring water, sewage water, lake water and stream water) were collected across Pakistan and evaluated for Naegleria species. Naegleria australiensis (pathogenic) and Naegleria lovaniensis (non pathogenic) were isolated on non nutrient agar plates and were further identified by PCR and sequencing. To best of our knowledge we have described for the first time the isolation and molecular identification of thermotolerant pathogenic and non pathogenicNaegleria species from diverse water samples including drinking water across Pakistan. The presence of pathogenic Naegleria species in diverse water samples may add the health threat to the community.
Lingyun Chen, Xiaolu Zhao, Hamed A. El-Serehy, Jie Huang, John C. Clamp
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 221 - 233
https://doi.org/10.4467/16890027AP.17.020.7822Tachysoma pellionellum Stokes, 1887, a freshwater ciliate isolated from Stone Mountain State Park, North Carolina, was studied in vivo and after staining with protargol. The population was characterized mainly by having the typical 18 frontal-ventral-transverse cirri; posterior ends of left and right marginal rows not confluent; five dorsal kineties and one dorsomarginal kinety; two macronuclear nodules near left cell margin with one or two micronuclei between them; contractile vacuole located at mid-body near left margin. Morphogenesis is characterized as follows: (1) in the proter, the parental adoral zone of membranelles is retained completely; (2) 18 frontal-ventral-transverse cirri are derived from the anlage of the undulating membrane and the five streaks of the frontal-ventral-transverse anlagen; (3) marginal rows develop intrakinetally; (4) anlagen of dorsal kineties 1, 2 and 4 develop in the parental structure and anlagen of dorsal kineties 2 and 4 fragment in the posterior region forming anlagen of dorsal kineties 3 and 5; (5) only one dorsomarginal kinety formed; (6) the two macronuclear nodules fuse into a single mass, which then divides. Phylogenetic analyses based on sequences of the gene coding for SSU RNA revealed a close relationship between T. pellionellum and the Oxytricha clade, both of which grouped with Kleinstyla dorsicirrata and Heterourosomoida lanceolata.
Eleni Gentekaki, Chitchai Chantangsi
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 235 - 243
https://doi.org/10.4467/16890027AP.17.021.7823Opaline is an unusual group of protists, characterized by the presence of flagella covering their whole body. They reside in the intestinal tracts of various animals, most notably amphibians. While there is a wealth of data regarding the morphological features of opalines, molecular data are extremely sparse. Consequently, the extent of diversity of this understudied group remains unknown. Here, we examine opalines from the intestinal tract of the amphibian Hoplobatrachus rugulosus in Thailand. We provide micrographs obtained from light and scanning electron microscopy of various opalinid morphotypes. Furthermore, we enrich the database of opaline sequences by providing new molecular data of the small subunit ribosomal DNA gene of these species. In our phylogenetic analyses, the newly derived sequences form a cluster sister to Protoopalina.
Liesl L. van As, Linda Basson, Jo Van As
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 245 - 254
https://doi.org/10.4467/16890027AP.17.022.7824Members of the Urceolariidae Dujardin, 1941 have been found associated with a wide variety of invertebrate hosts from freshwater and marine habitats. Five species have been described from molluscan hosts from Europe and America. This paper deals with an urceolariid (Leiotrocha Fabre-Domergue, 1888) collected from the gills of Cellana radiata capensis (Gmelin, 1791) and Scutellastra exusta (Reeve, 1854) from the east coast of South Africa, as well as Patella depressa Pennant, 1777 and Cymbula safiana (Lamarck, 1891) from the bulge (west coast) of Africa. A higher prevalence was found on C. radiata capensis (89%) and P. depressa (72%) compared to the other two hosts. The urceolariid collected from the African limpets was identified as L. patellae (Cuénot, 1891). This is the first record of an urceolariid from any African hosts, including representatives of the Mollusca. Five urceolariid species were identified and described from gastropods, i.e. L. patellae Cuénot, 1891,U. karyolobia Hirshfield, 1949, U. cellanae Suzuki, 1950, U. viridis Richards, 1971 and U. parakorschelti Irwin, Sabetrasekh and Lynn, 2017. Motivation is provided why U. cellanae and U. viridis should be reallocated to the genus Leiotrocha, and U. karyolobia not. The taxonomic validity of the recent description of U. parakorschelti from limpets is commented on.
Ľubomír Rajter, Peter Vďačný
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 255 - 281
https://doi.org/10.4467/16890027AP.17.023.7825We investigated interrelationships between four free-living litostomatean lineages, using 18S rRNA gene and ITS region sequences as well as the secondary structure of the ITS2 molecules. Our phylogenetic analyses confirmed the deep split of free-living litostomateans into Rhynchostomatia and Haptoria represented here by Haptorida, Pleurostomatida, and Spathidiida. This bifurcation is also corroborated by the signature of the rhynchostomatian and haptorian ITS2 molecules. Specifically, the consensus stems of helices II and III are longer by one base pair in Rhynchostomatia, while the terminal loops of both helices are longer by one or two nucleotide/-s in Haptoria. A close relationship of Pleurostomatida and Haptorida is favored by quartet likelihood-mapping and supported by a 5’-AG vs. CU-3’ motif in the variable part of helix II and by two morphological apomorphies, i.e., meridionally extending somatic kineties and a non-three-rowed dorsal brush. Although monophyletic origin of Spathidiida is poorly supported in phylogenetic trees, the unique motif 5’-GA vs. UC-3’ present in the consensus helix II stem could be an important molecular synapomorphy of spathidiids, apart from the ancestrally anteriorly curved somatic kineties and the three-rowed dorsal brush. The peculiar family Pseudoholophryidae has very likely found its phylogenetic home among spathidiids, as an early branching lineage.
Mustafa Yaman
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 283 - 288
https://doi.org/10.4467/16890027AP.17.024.7826Chrysomela populi L. (Coleoptera; Chrysomelidae) is one of the most serious pests affecting poplars. Chemical control is the most widely known suppressive method against this pest. This method is not acceptable in urban forests because of their proximity to people. Entomopathogenic organisms are environmentally friendly control agents and suppress the pest populations under natural conditions. In the present study, the occurrence and distribution ofanew entomopathogenic protist,aneogregarine, Ophryocystis anatoliensis (Apicomplexa) in C. populi populations andamember of the family Chrysomelidae is presented for the first time. In total, 90 of 2185 C.populiadults and larvae collected from 16 localities during three years (from 2013 to 2015) were found to be infected by this pathogen. Neogregarine infection was observed in 14 of 16 investigated C. populi populations. The infection was variable between the populations and years. These results confirm that the neogregarine pathogen hasahigh dispersal potential through the C. populi populations and can be an effective natural biological suppressing factor on the pest populations.
Jing Li, Kun Yang, Feizhou Chen, Wenxuan Lu, Ting Fang, Xiuxia Zhao, Haiyang Li, Kai Cui
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 289 - 301
https://doi.org/10.4467/16890027AP.17.025.7827Direct and indirect effects of crustacean zooplankton (cladocerans and copepods) are important regulators of ciliate communities, especially in eutrophic systems. However, it is not clear whether pseudodiaptomids (e.g., Schmackeria), one of the dominant calanoid copepods in Chinese lakes, effectively impacts natural ciliate communities. The impacts of small-bodied cladocerans (e.g., Bosmina) on ciliates are also controversial.
We performed an incubation experiment using winter lake water from Lake Chaohu to assess the structuring effects that crustacean zooplankton have on natural ciliate populations. The presence and absence of cladocerans (Bosmina sp.) and copepods (Schmackeria inopinus) were alternated in four treatments.
Both Bosmina sp. and Schmackeria inopinus had substantial impacts on ciliate abundance, biomass, and community structure. The response of ciliates was different in the presence of Bosmina sp. compared with Schmackeria inopinus and varied among categories such as the ciliate population, relative body size and functional feeding group. Our results also highlight the importance of interference and exploitative competition among metazooplankton groups.
Xinlu Shi, Guijie Liu, Chundi Wang, Xiaozhong Hu
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 303 - 315
https://doi.org/10.4467/16890027AP.17.026.7828A brackish water euplotid ciliate, Uronychia xinjiangensis n. sp., was discovered in a ditch in Yuli County, Xinjiang, China. Its morphology, ciliature and morphogenesis were investigated based on specimens examined in vivo and following protargol staining. The new species is characterized by the posterior part of the adoral zone composed of three membranelles, which has never been seen in all other known congeners. Other morphologic features include: (i) body oval-shaped, with conspicuous right anterior spur-like protrusion;
(ii)size in vivo 60–90 × 40–68 μm; (iii) two macronuclear nodules; (iv) four frontal, two ventral, five transverse, three left marginal and three caudal cirri. Its morphogenesis proceeds in a usual way, except that the oral primordium forms only three proximal membranelles rather than four proximal membranelles within congeners. The small subunit rRNA gene of the new species (GenBank accession number: KX147287) comprises 1723 bp and 44.63% GC content, and differs by 0.12–1.81% from those of congeners. Phylogenetic analyses based on SSU rRNA gene sequence data reveal that Uronychia xinjiangensis n. sp. clusters with other Uronychia species with full support, which supports the monophyly of the genus Uronychia Stein, 1859.
Tania Tanveer, Abdul Hameed, Abdul-Aziz A. Bin-Dukhyil, Mohammed Alaidarous, Abdul Matin
Acta Protozoologica, Volume 56, Issue 4, 2017, pp. 317 - 322
https://doi.org/10.4467/16890027AP.17.027.7829Naegleria is well recognized for primary amoebic meningoencephalitis which always results into death. To date there is not a single report demonstrating molecular identification of Naegleria from water resources of Pakistan thus the aim of the proposed study.Here, in total 135 various water samples (like domestic tap water, municipal water, sea water, well water, tube well water, canal water, boring water, sewage water, lake water and stream water) were collected across Pakistan and evaluated for Naegleria species. Naegleria australiensis (pathogenic) and Naegleria lovaniensis (non pathogenic) were isolated on non nutrient agar plates and were further identified by PCR and sequencing. To best of our knowledge we have described for the first time the isolation and molecular identification of thermotolerant pathogenic and non pathogenicNaegleria species from diverse water samples including drinking water across Pakistan. The presence of pathogenic Naegleria species in diverse water samples may add the health threat to the community.
Publication date: 13.12.2017
Editor-in-Chief: Krzysztof Wiąckowski
Zoya I. Uspenskaya, Alexander L. Yudin
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 139 - 147
https://doi.org/10.4467/16890027AP.17.012.7493A previously unrecorded property of actinomycin D, a well-known antibiotic, was discovered in the course of long-term genetic research on the amoeba Amoeba proteus and the ciliate Dileptus anser. In these protists actinomycin D can induce an unusual type of hereditary variation, which we refer to as the inheritable destabilization of characters. A number of features indicate that this variation is epigenetic, that is, not caused by mutations in the DNA. Therefore, actinomycin D may be considered as an inducer of epigenetic inheritable changes, in other words, as an epimutagen.
Xin Sheng, Yan Sheng, Yuehua Liu, Junhua Wang
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 149 - 160
https://doi.org/10.4467/16890027AP.17.013.7494Ji Hye Moon, Ji Hye Kim, Jae-Ho Jung
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 161 - 169
https://doi.org/10.4467/16890027AP.17.014.7495Brackish water populations of Pinacocoleps pulcher were collected from a lagoon in Korea. This species has never been described using silver impregnation and nuclear small subunit ribosomal RNA (SSU rRNA) gene. In the present study, we investigated the morphological and molecular attributes of P. pulcher using standard methods. The morphology was studied based on observations of live materials, silver-impregnated preparations, and scanning electron microscopy. The morphological characteristics are as follows: body size 80–90 × 40–50 µm in vivo, shape broadly ellipsoidal, body cross-section ellipsoidal, about seven anterior spines and about seven posterior spines, approximately 21 somatic ciliary rows, one macronucleus and one micronucleus, and a single caudal cilium. The SSU rRNA gene tree supports a sister relationship of P. pulcher to the genus Apocoleps, not P. tesselatus.
Gözde Gürelli, Fatma Tül Büşra Akman
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 171 - 180
https://doi.org/10.4467/16890027AP.17.015.7496Alvaro De Obeso Fernadez Del Valle, Sutherland K. Maciver
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 181 - 189
https://doi.org/10.4467/16890027AP.17.016.7497We report the isolation of a new species of Allovahlkampfia, a small cyst-forming heterolobosean soil amoeba. Phylogenetic analysis of the 18S rDNA and the internal transcribed spacers indicates that Allovahlkampfia is more closely related to the acrasids than to other heterolobosean groups and indicates that the new strain (GF1) groups with Allovahlkampfia tibetiensis and A. nederlandiensis despite being significantly smaller than these and any other described Allovahlkampfia species. GF1 forms aggregated cyst masses similar to the early stages of Acrasis sorocarp development, in agreement with the view that it shares ancestry with the acrasids. Time-lapse video microscopy reveals that trophozoites are attracted to individuals that have already begun to encyst or that have formed cysts. Although some members of the genus are known to be pathogenic the strain GF1 does not grow above 28oC nor at elevated osmotic conditions, indicating that it is unlikely to be a pathogen.
Isabelle Koenig, Florence Schwendener, Matthieu Mulot, Edward A. D. Mitchell
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 191 - 210
https://doi.org/10.4467/16890027AP.17.017.7498Satoshi D. Shimano, Anatoly Bobrov, Manfred Wanner, Mariusz Lamentowicz, Yuri Mazei, Taisuke Ohtsuka
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 211 - 216
https://doi.org/10.4467/16890027AP.17.018.7499John R. Dolan, Eun Jin Yang
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 217 - 220
https://doi.org/10.4467/16890027AP.17.019.7500Zoya I. Uspenskaya, Alexander L. Yudin
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 139 - 147
https://doi.org/10.4467/16890027AP.17.012.7493A previously unrecorded property of actinomycin D, a well-known antibiotic, was discovered in the course of long-term genetic research on the amoeba Amoeba proteus and the ciliate Dileptus anser. In these protists actinomycin D can induce an unusual type of hereditary variation, which we refer to as the inheritable destabilization of characters. A number of features indicate that this variation is epigenetic, that is, not caused by mutations in the DNA. Therefore, actinomycin D may be considered as an inducer of epigenetic inheritable changes, in other words, as an epimutagen.
Xin Sheng, Yan Sheng, Yuehua Liu, Junhua Wang
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 149 - 160
https://doi.org/10.4467/16890027AP.17.013.7494Ji Hye Moon, Ji Hye Kim, Jae-Ho Jung
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 161 - 169
https://doi.org/10.4467/16890027AP.17.014.7495Brackish water populations of Pinacocoleps pulcher were collected from a lagoon in Korea. This species has never been described using silver impregnation and nuclear small subunit ribosomal RNA (SSU rRNA) gene. In the present study, we investigated the morphological and molecular attributes of P. pulcher using standard methods. The morphology was studied based on observations of live materials, silver-impregnated preparations, and scanning electron microscopy. The morphological characteristics are as follows: body size 80–90 × 40–50 µm in vivo, shape broadly ellipsoidal, body cross-section ellipsoidal, about seven anterior spines and about seven posterior spines, approximately 21 somatic ciliary rows, one macronucleus and one micronucleus, and a single caudal cilium. The SSU rRNA gene tree supports a sister relationship of P. pulcher to the genus Apocoleps, not P. tesselatus.
Gözde Gürelli, Fatma Tül Büşra Akman
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 171 - 180
https://doi.org/10.4467/16890027AP.17.015.7496Alvaro De Obeso Fernadez Del Valle, Sutherland K. Maciver
Acta Protozoologica, Volume 56, Issue 3, 2017, pp. 181 - 189
https://doi.org/10.4467/16890027AP.17.016.7497We report the isolation of a new species of Allovahlkampfia, a small cyst-forming heterolobosean soil amoeba. Phylogenetic analysis of the 18S rDNA and the internal transcribed spacers indicates that Allovahlkampfia is more closely related to the acrasids than to other heterolobosean groups and indicates that the new strain (GF1) groups with Allovahlkampfia tibetiensis and A. nederlandiensis despite being significantly smaller than these and any other described Allovahlkampfia species. GF1 forms aggregated cyst masses similar to the early stages of Acrasis sorocarp development, in agreement with the view that it shares ancestry with the acrasids. Time-lapse video microscopy reveals that trophozoites are attracted to individuals that have already begun to encyst or that have formed cysts. Although some members of the genus are known to be pathogenic the strain GF1 does not grow above 28oC nor at elevated osmotic conditions, indicating that it is unlikely to be a pathogen.
