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The phagotrophic flagellates described as "typical excavates" have been hypothesized to be morphologically similar to the Last Eukaryotic Common Ancestor and understanding the functional ecology of excavates may therefore help shed light on the ecology of these early eukaryotes. Typical excavates are characterized by a posterior flagellum equipped with a vane that beats in a ventral groove. Here, we combined flow visualization and observations of prey capture in representatives of the three clades of excavates with computational fluid dynamic modeling, to understand the functional significance of this cell architecture. We record substantial differences amongst species in the orientation of the vane and the beat plane of the posterior flagellum. Clearance rate magnitudes estimated from flow visualization and modeling are both like that of other similarly sized flagellates. The interaction between a vaned flagellum beating in a confinement is modeled to produce a very efficient feeding current at low energy costs, irrespective of the beat plane and vane orientation and of all other morphological variations. Given this predicted uniformity of function, we suggest that the foraging systems of typical excavates studied here may be good proxies to understand those potentially used by our distant ancestors more than 1 billion years ago. [ABSTRACT FROM AUTHOR]

As predators of bacteria and viruses and as food sources for microzooplankton, heterotrophic flagellates (HFs) play an important role in the marine micro-food web. Based on the global climate change's impact on marine ecosystems, particularly sea ice melting, we analyzed the community composition and diversity of heterotrophic flagellates, focusing on the Antarctic Cosmonaut Sea. During the 36th China Antarctic research expedition (2019-2020), we collected seawater samples, subsequently analyzing HFs through IlluminaMiSeq2000 sequencing to assess community composition and diversity. Notable variations in HFs abundance were observed between the western and eastern sectors of the Cosmonaut Sea, with a distinct concentration at a 100-meter water depth. Different zones exhibited diverse indicators and dominants taxa influenced by local ocean currents. Both the northern Antarctic Peninsula and the western Cosmonaut Sea, where the Weddell Eddy and Antarctic Land Slope Current intersect, showcased marine stramenopiles as dominant HFs species. Our findings offer insights into dominant taxa, spatial distribution patterns among heterotrophic flagellates, correlations between taxa distribution and environmental factors, and the exploration of potential indicator taxa. [ABSTRACT FROM AUTHOR]

Phagotrophic flagellates are the main consumers of bacteria and picophytoplankton. Despite their ecological significance in the 'microbial loop', many of their predation mechanisms remain unclear. 'Typical excavates' bear a ventral groove, where prey is captured for ingestion. The consequences of feeding through a 'semi‐rigid' furrow on the prey size range have not been explored. An unidentified moving element called 'the wave' that sweeps along the bottom of the groove toward the site of phagocytosis has been observed in a few species; its function is unclear. We investigated the presence, behavior, and function of the wave in four species from the three excavate clades (Discoba, Metamonada, and Malawimonadida) and found it present in all studied cases, suggesting the potential homology of this feature across all three groups. The wave displayed a species‐specific behavior and was crucial for phagocytosis. The morphology of the feeding groove had an upper‐prey size limit for successful prey captures, but smaller particles were not constrained. Additionally, the ingestion efficiencies were species dependent. By jointly studying these feeding traits, we speculate on adaptations to differences in food availability to better understand their ecological functions. [ABSTRACT FROM AUTHOR]

The Galician estuaries are Europe's foremost supplier of mussels, generating millions of euros annually and offering substantial employment opportunities for its population. One of the most critical threats to shellfish production is the occurrence of harmful algal blooms (HABs), contaminating bivalves with phytotoxins. To successfully tackle this problem, there needs to be a collaborative effort between the scientific community and decision-makers to establish a dynamic and effective monitoring system. This could enable early warnings and preventive actions to avert the loss of millions of tons of shellfish. Remote sensing, despite its limitations, requires commitment and effort by experts to devise effective methods for detecting target optical constituents mixed with other undesired target but that exhibit strong signals. Therefore, the essential necessity arises to identify approaches for mitigating the shortcomings of the undertaken efforts. The objective of this study is to assess the main environmental drivers of potential harmful genera (Pseudo-nitzschia, Dinophysis, Alexandrium, and Gymnodinium) in the Rías Baixas from 2015 to 2022, developing regression-based models and customizing Generalized Additive Models (GAMs) to investigate their spatial-temporal dynamics. Risk-susceptible bloom zones were identified in the river mouth of the Ría Pontevedra and from the center to offshore of the Ría Vigo. Early upwelling events triggered peaks in chlorophyll-a (Chl-a), driving Dinophysis grazing on phytoplankton communities mainly dominated by diatoms, flagellates, and ciliates. Subsequently, the upwelling intensity favoring Pseudo-nitzschia or Alexandrium minutum growth as larger diatoms declined. A. minutum exhibited elevated incidence over the past five years. Gymnodinium catenatum presented a rare occurrence across the three studied estuaries, which limited the assessment of its spatial dynamics in the region. This study emphasizes the need to integrate remote sensing evaluation of high-risk bloom areas (July to September), in-situ cell count collection, and enhanced efforts for forecasting future critical occurrences of HABs. [ABSTRACT FROM AUTHOR]

Eukaryotrophic protists are ecologically significant and possess characteristics key to understanding the evolution of eukaryotes; however, they remain poorly studied, due partly to the complexities of maintaining predator–prey cultures. Kaonashia insperata, gen. nov., et sp. nov., is a free‐swimming biflagellated eukaryotroph with a conspicuous ventral groove, a trait observed in distantly related lineages across eukaryote diversity. Di‐eukaryotic (predator–prey) cultures of K. insperata with three marine algae (Isochrysis galbana, Guillardia theta, and Phaeodactylum tricornutum) were established by single‐cell isolation. Growth trials showed that the studied K. insperata clone grew particularly well on G. theta, reaching a peak abundance of 1.0 × 105 ± 4.0 × 104 cells ml−1. Small‐subunit ribosomal DNA phylogenies infer that K. insperata is a stramenopile with moderate support; however, it does not fall within any well‐defined phylogenetic group, including environmental sequence clades (e.g. MASTs), and its specific placement remains unresolved. Electron microscopy shows traits consistent with stramenopile affinity, including mastigonemes on the anterior flagellum and tubular mitochondrial cristae. Kaonashia insperata may represent a novel major lineage within stramenopiles, and be important for understanding the evolutionary history of the group. While heterotrophic stramenopile flagellates are considered to be predominantly bacterivorous, eukaryotrophy may be relatively widespread amongst this assemblage. [ABSTRACT FROM AUTHOR]

Submerged macrophytes play crucial roles in maintaining the stability of clear-water states in shallow lakes. Recent stable isotope studies have shown that crustacean zooplankton can utilize submerged macrophyte carbon, but macrophytes alone cannot support the growth and reproduction of such grazers, being deficient in highly unsaturated fatty acids (HUFA). We hypothesized that flagellates feeding on macrophytes can synthesize HUFA and thereby support crustacean zooplankton. To test this hypothesis, we conducted a feeding experiment in which Daphnia magna were provided with a diet of submerged macrophyte Hydrilla verticillata detritus which had been degraded by lake microbes. The chlorophyte Scenedesmus bijuga and undegraded macrophyte detritus were used as controls for comparison of Daphnia's performance. Using biochemical analysis, we examined how the degradation process affected the food quality of the macrophyte. Flagellates were subsequently isolated from the degraded macrophyte and cultured heterotrophically to detect their HUFA synthesis. The 5-day degraded H. verticillata showed significantly higher HUFA concentrations than undegraded macrophyte detritus. They supported better Daphnia performance than undegraded macrophyte, being comparable with S. bijuga. Two isolated flagellates (SL-1 and SL-2), identified as Ochromonas sp. and Poterioochromonas sp., were found to contain HUFA when cultured heterotrophically without dietary sources of fatty acids, suggesting their HUFA synthesis ability. Our results demonstrate that submerged macrophytes may thus indirectly support crustacean zooplankton via flagellate mediation. As crustacean zooplanktons are of key importance for water quality in the grazer control of phytoplankton, this microbial facilitation may contribute to the maintenance of macrophyte clear-water conditions in shallow lakes. [ABSTRACT FROM AUTHOR]

Since the skin limits the distribution of intradermal vaccines, a large number of dendritic cells in the skin cannot be fully utilized to elicit a more effective immune response. Here, we loaded the antigen to the surface of the flagellate bacteria that was modified by cationic polymer, thus creating antigen-loaded flagellate bacteria (denoted as 'FB-Ag') to overcome the skin barrier and perform the active delivery of antigen in the skin. The FB-Ag showed fast speed (∼0.2 μm s−1) and strong dendritic cell activation capabilities in the skin model in vitro. In vivo, the FB-Ag promoted the spread of antigen in the skin through active movement, increased the contact between Intradermal dendritic cells and antigen, and effectively activated the internal dendritic cells in the skin. In a mouse of pulmonary metastatic melanoma and in mice bearing subcutaneous melanoma tumor, the FB-Ag effectively increased antigen-specific therapeutic efficacy and produced long-lasting immune memory. More importantly, the FB-Ag also enhanced the level of COVID-19 specific antibodies in the serum and the number of memory B cells in the spleen of mice. The movement of antigen-loaded flagellate bacteria to overcome intradermal constraints may enhance the activation of intradermal dendritic cells, providing new ideas for developing intradermal vaccines. [Display omitted] [ABSTRACT FROM AUTHOR]

Microbial interactions including competition, mutualism, commensalism, parasitism, and predation, which can be triggered by nutrient acquisition and chemical communication, are universal phenomena in the marine ecosystem. The interactions may influence the microbial population density, metabolism, and even their environmental functions. Herein, we investigated the interaction between a heterotrophic bicosoecid flagellate, Pseudobodo sp. (Bicoecea), and a dinoflagellate, Gambierdiscus balechii (Dinophyceae), which is a well-known ciguatera food poisoning (CFP) culprit. The presence of Pseudobodo sp. inhibited the algal proliferation and decreased the cardiotoxicity of zebrafish in the algal extract exposure experiment. Moreover, a significant difference in microbiome abundance was observed in algal cultures with and without Pseudobodo sp. Chemical analysis targeting toxins was performed by using liquid chromatography-tandem mass spectrometry (LC-MS/MS) combined with molecular networking (MN), showing a significant alteration in the cellular production of gambierone analogs and some super-carbon chain compounds. Taken together, our results demonstrated the impact of heterotrophic flagellate on the photosynthetic dinoflagellates, revealing the complex dynamics of algal toxin production and the ecological relationships related to dinoflagellates in the marine environment. [ABSTRACT FROM AUTHOR]

The heterotrophic flagellates, Oxyrrhis marina were first suggested to feed Amphiascopsis cinctus, and the effects on the growth and survival rate of Amphiascopsis cinctus were studied. The results showed that the Amphiascopsis cinctus feed on Oxyrrhis marina of different concentrations finished its development and reproduction in different speed. When the Oxyrrhis marina concentrations were 200 ind·mL–1, 800 ind·mL–1, 3200 ind·mL–1 and > 10 4 ind·mL–1 respectively, the increasing concentration of Oxyrrhis marina considerably shorten the development time of Amphiascopsis cinctus between nauplii to copepodid stage from (16.30±0.82) d to (9.06±0.87) d, between copepodid stage to adult stage from (15.94±0.63) d to (10.14± 1.07) d. With the increasing concentration of flagellates, the survival rate of Amphiascopsis cinctus from nauplii to copepodid and from copepodid to adult increased from 36.72% to 70.25% and from 70.88% to 85.62% respectively, but the highest survival rate was found in the group with lower concentration (3200 ind·mL–1 ). With the increasing of food concentration, the brood amount and the hatching rate of Amphiascopsis cinctus increased from7.86 to10.67; 50.83% to 85.30% respectively, and the incubation time decreased from 8.67d to 5.12d. It can be seen that high concentration of Oxyrrhis marina can accelerate the development of Amphiascopsis cinctus and increase their reproduction efficiency. However, high concentration of flagellates reduces the survival rate of the stage from copepodid to adult, which needs further study. [ABSTRACT FROM AUTHOR]

Mixotrophic and heterotrophic protists hold a key position in aquatic microbial food webs. Whereas they can account for the bulk of bacterivory in pelagic systems, the potential structuring effect of these consumers on bacterial communities is far from clear. We conducted short-term grazing experiments to test for the overall impact on bacterial community structure and possible prey preferences of phagotrophic protists. The protist taxa selected for this study include three mixotrophic flagellates, comprising two obligate- and one facultative mixotroph, and one phagoheterotrophic flagellate lacking phototrophic capacity. Bacterioplankton from seven different lakes were enriched and used to represent semi-natural prey communities. Our study demonstrated protist strain specific impacts on bacterial community composition linked to grazing. The three mixotrophs had variable impacts on bacterial communities where the two obligate mixotrophs exhibited lower grazing rates, while showing a tendency to promote higher bacterial diversity. The phagoheterotroph displayed the highest grazing rates and structured the bacterial communities via apparent selective grazing. Consistent selectivity trends were observed throughout the experiments, such as the apparent avoidance of all flagellates of Actinobacteria, and high grazing on dominant Burkholderiales taxa. However, there was no consistent "fingerprint" of mixotrophic grazing on prey communities, but the structuring impact rather seemed to depend on the trophic mode of the individual protist taxa, i.e. their dependence on phototrophy vs. phagotrophy. Our findings highlight the differential structuring impact of protist taxa on bacterial communities which may have important ecological implications, for example during periodic dominance of obligate mixotrophic bacterivores in changing lake ecosystems. [ABSTRACT FROM AUTHOR]

Euglenids are a diverse group of flagellates that inhabit most environments and exhibit many different nutritional modes. The most prominent euglenids are phototrophs, but phagotrophs constitute the majority of phylogenetic diversity of euglenids. They are pivotal to our understanding of euglenid evolution, yet we are only starting to understand relationships amongst phagotrophs, with the backbone of the tree being most elusive. Ploeotids make up most of this backbone diversity—yet despite their morphological similarities, SSU rDNA analyses and multigene analyses show that they are non‐monophyletic. As more ploeotid diversity is sampled, known taxa have coalesced into some subgroups (e.g. Alistosa), but the relationships amongst these are not always supported and some taxa remain unsampled for multigene phylogenetics. Here, we used light microscopy and single‐cell transcriptomics to characterize five ploeotid euglenids and place them into a multigene phylogenetic framework. Our analyses place Decastava in Alistosa; while Hemiolia branches with Liburna, establishing the novel clade Karavia. We describe Hemiolia limna, a freshwater‐dwelling species in an otherwise marine clade. Intriguingly, two undescribed ploeotids are found to occupy pivotal positions in the tree: Chelandium granulatum nov. gen. nov. sp. branches as sister to Olkasia, and Gaulosia striata nov. gen. nov. sp. remains an orphan taxon. [ABSTRACT FROM AUTHOR]

This work is a floristic study of Selaginella in Maranhão. The species survey is based on collections from fieldwork conducted between April 2006 and February 2023 and specimens from Maranhão deposited at the CCAA, HBRA, MG, and SLUI herbaria. Ten species were identified: Selaginella conduplicata, S. convoluta, S. erythropus, S. flagellata, S. gynostachya S. marginata, S. minima, S. radiata, S. simplex, and S. sulcata. We report the first record of S. gynostachya for Maranhão and the Cerrado domain in Brazil. Until now, this species was only known from areas of Amazonia. We provide a map with records, an identification key, and comments about the identification and geographic distribution of Selaginella species in Maranhão state. For the new record, we also provide photos. [ABSTRACT FROM AUTHOR]

Heterosigma akashiwo is a unicellular microalga which can cause massive mortality in both wild and cultivated fish worldwide, resulting in substantial economic losses. Environmental parameters such as salinity, light, and temperature showed a significant effect on bloom initiation and the toxicity of H. akashiwo. While in previous studies a one-factor-at-a-time (OFAT) approach was utilized, which only changes one variable at a time while keeping others constant, in the current study a more precise and effective design of experiment (DOE) approach, was used to investigate the simultaneous effect of three factors and their interactions. The study employed a central composite design (CCD) to investigate the effect of salinity, light intensity, and temperature on the toxicity, lipid, and protein production of H. akashiwo. A yeast cell assay was developed to assess toxicity, which offers rapid and convenient cytotoxicity measurements using a lower volume of samples compared to conventional methods using the whole organism. The obtained results showed that the optimum condition for toxicity of H. akashiwo was 25 °C, a salinity of 17.5, and a light intensity of 250 μmol photons m−2 s−1. The highest amount of lipid and protein was found at 25 °C, a salinity of 30, and a light intensity of 250 μmol photons m−2 s−1. Consequently, the combination of warm water mixing with lower salinity river input has the potential to enhance H. akashiwo toxicity, which aligns with environmental reports that establish a correlation between warm summers and extensive runoff conditions that indicate the greatest concern for aquaculture facilities. [ABSTRACT FROM AUTHOR]

Background: Marine heterotrophic flagellates (HF) are dominant bacterivores in the ocean, where they represent the trophic link between bacteria and higher trophic levels and participate in the recycling of inorganic nutrients for regenerated primary production. Studying their activity and function in the ecosystem is challenging since most of the HFs in the ocean are still uncultured. In the present work, we investigated gene expression of natural HF communities during bacterivory in four unamended seawater incubations. Results: The most abundant species growing in our incubations belonged to the taxonomic groups MAST-4, MAST-7, Chrysophyceae, and Telonemia. Gene expression dynamics were similar between incubations and could be divided into three states based on microbial counts, each state displaying distinct expression patterns. The analysis of samples where HF growth was highest revealed some highly expressed genes that could be related to bacterivory. Using available genomic and transcriptomic references, we identified 25 species growing in our incubations and used those to compare the expression levels of these specific genes. 8L85edCQnxTD9xJZeGdCik Video Abstract Conclusions: Our results indicate that several peptidases, together with some glycoside hydrolases and glycosyltransferases, are more expressed in phagotrophic than in phototrophic species, and thus could be used to infer the process of bacterivory in natural assemblages. [ABSTRACT FROM AUTHOR]

Our knowledge of the ecology of non-marine Ostracoda inhabiting endorheic wetlands (pans) of the semi-arid regions of South Africa is very scarce. The present study investigates the distribution of ostracod species in grass, open, and salt pans in the central part of the North West province and tests ostracod response to abiotic and biotic predictor variables operating at a local scale. Distance-based linear models revealed three variables (pan type, water electrical conductivity and abundance of macroinvertebrate predators, and collector-gatherers) that best explained variation in the ostracod dataset. Ostracod assemblages from the three studied pan types differed by the dominance structure rather than by the species composition. Salt pans with high conductivity and high ratio of predaceous macroinvertebrates were dominated by Heterocypris giesbrechti, with accessory presence of Plesiocypridopsis newtoni. In open pans with low conductivities and the lowest ratio of predators (but highest ratio of collector-gatherers) Potamocypris mastigophora was typically a dominant species, while in grass pans, all the three mentioned species had similar relative abundances. Although our findings lend provisional support to some models of ostracod assemblage diversity across different pan types, more studies replicating endorheic depression wetlands in other regions are required before generalizations can be made. [ABSTRACT FROM AUTHOR]

Based on the obtained and all available literature data, it has been shown that the abundance of heterotrophic flagellates in the Kara Sea at the end of the season is relatively stable in different years, while in other Arctic seas (East Siberian and Chukchi seas) the values of this indicator are 1.5–2 times higher. The indicators of the abundance of heterotrophic nanoflagellates in bottom water vary to a much lesser extent than in the water column. The abundance of heterotrophic nanoflagellates in the bottom water of the bays of the Novaya Zemlya archipelago is significantly lower than in the same biotopes in the eastern and western parts of the Kara Sea. Most organisms are free-living forms. About a third of protozoa are associated with detrital particles. The ratio of the biomass of heterotrophic flagellates to that of bacteria more than doubles in the layer of bottom water and in the upper layer of sediments compared to the water column. For the water column of the Kara Sea, the calculated value of grazing of bacterioplankton by flagellates does not exceed 2% of their biomass. The ratio of the eaten biomass of bacterioplankton to the biomass of consumers in most cases decreases with depth. [ABSTRACT FROM AUTHOR]

Globally, observations on marine species during marine heatwaves (MHWs) help outline the scope of the MHW's possible biological effects. In line with this effort, this paper presents a 2020 MHW that coincided with a reported "tomato jellyfish" (Crambione mastigophora Maas, 1903) bloom on 23 March 2020 in the Corong-Corong Bay of Palawan, Philippines. Detecting a moderate MHW from 21 March to 04 April 2020, the analysis of sea surface temperatures revealed that most areas surrounding the bloom site attained their peak positive anomalies on the same day as the reported bloom. Certain physical mechanisms present in the first quarter of 2020 may have played a role in the occurrence of both events: the presence of cyclonic eddies and parallel monsoonal winds alongshore can induce upwelling which promotes biological productivity in surface waters, while the observed weakening of winds have been associated with anomalous warming of the sea surface. Further studies are still highly recommended to determine the exact causes of the jellyfish bloom and what conditions make it more likely to happen during MHWs. However, if the C. mastigophora is hypothetically able to continually bloom amidst warming temperatures, the increasing trend of MHW frequency and intensity in the West Philippine Sea (where the reported bloom site is situated) may consequently yield more future co-occurrences. This paper aims to hopefully contribute to the existing knowledge of possible biological impacts associated with extreme marine events, especially in the Philippine context where both jellyfish blooms and MHWs are understudied. [ABSTRACT FROM AUTHOR]

In sunlit waters, significant predation is performed by unicellular, phagotrophic mixotrophs, that is, predators that also possess plastids. The success of a mixotrophic lifestyle will depend in part on how well mixotrophs acquire prey relative to specialized heterotrophs. Likewise, consequences of mixotrophy for productivity and element cycling will depend on the rate and efficiency at which mixotrophs consume prey biomass relative to heterotrophs. However, trait differences between mixotrophs and heterotrophs are not well characterized. In addition, cell size of mixotrophs varies widely, and constitutive mixotrophs include small flagellates deriving from diverse taxa, while larger species are primarily dinoflagellates. To determine whether similar constraints apply to phagotrophs across this broad range of size and taxa, we compiled 83 measurements of flagellate functional responses and compared maximum clearance rates (Cmax) and maximum ingestion rates (Imax) between trophic modes. We found that the average mixotroph has a 3.7‐fold lower Cmax and 7.8‐fold lower Imax than the average heterotroph, after controlling for cell size. The smaller penalty for Cmax suggests that relative fitness of mixotrophs will be enhanced under dilute prey concentrations that are common in pelagic ecosystems. We also find that growth efficiency is greater for mixotrophs and for flagellates with lower Cmax, indicating a spectrum of trophic strategies that may be driven by phototrophy vs. phagotrophy allocation as well as fast vs. slow metabolic variation. Allometric scaling shows that Imax is constrained by a common relationship among dinoflagellates and other taxa, but dinoflagellates achieve a greater volume‐specific Cmax. These results should aid in interpreting protistan communities and modeling mixotrophy. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) provide a central mechanism of cell–cell communication. While EVs are found in most organisms, their pathogenesis-promoting roles in parasites are of particular interest given the potential for medical insight and consequential therapeutic intervention. Yet, a key feature of EVs in human parasitic protozoa remains elusive: their mechanisms of biogenesis. Here, we survey the current knowledge on the biogenesis pathways of EVs secreted by the four main clades of human parasitic protozoa: apicomplexans, trypanosomatids, flagellates, and amoebae. In particular, we shine a light on findings pertaining to the Endosomal Sorting Complex Required for Transport (ESCRT) machinery, as in mammals it plays important roles in EV biogenesis. This review highlights the diversity in EV biogenesis in protozoa, as well as the related involvement of the ESCRT system in these unique organisms. [ABSTRACT FROM AUTHOR]

The snail Pomacea flagellata inhabits aquatic systems with high calcium concentration and it is important to food webs; unfortunately, its natural populations are decreasing due to overfishing and habitat destruction. Here we tested the effect of three water calcium concentrations on the growth and hardness of snail shells in triplicate recirculation culture systems for 12 weeks. In each culture, 100 juvenile snails were seeded at constant density and fed with balanced tilapia feed. Thirty snails were randomly collected every 15 days and measured in length and total weight. The size, weight, and shell hardness of the snails for the 500 mg/L calcium treatment were significantly higher than the mean size of the snails in the other treatments (300 mg/L and 243.33 mg/L). The calcium supply in the culture promotes growth and allows the snails to produce healthier and stronger shells, in addition to improving their growth rate, which is important for the management of the species. [ABSTRACT FROM AUTHOR]

Over four years in the spring–summer period, the species composition and the community structure of planktonic heterotrophic nanoflagellates (HNF) were studied in different types of littoral waters of the Rybinsk Reservoir (Upper Volga), including those affected by the vital activity of colonial birds. A total of 105 species and forms of HNF from 13 large taxa and a group of uncertain taxonomic position were identified. The taxa Choanoflagellida and Chrysomonadida were represented by the largest number of species in all the littoral zones studied. Fewer species of HNF were recorded in the littoral zone affected by the bird colonies than in areas outside the zones of their influence. The maximum number of species (81) was recorded in the protected overgrown littoral zone, and the minimum (48 species), in the open littoral zone near the heron colony. In the entire littoral area, 35 species were common. Among them, three species (Bodo designis, Paraphysomonas imperforata, and Spumella sp. 1) had a high frequency of occurrence (≥50%). However, the basis of the diversity of the GNF was formed by the species, the frequency of occurrence of which was less than 20%. However, the species the frequency of which was ≤20% were the basis for the diversity of HNF. They made up more than half of the species list in all habitats. The dominant complex of the littoral communities in the reservoir was represented by 19 species. [ABSTRACT FROM AUTHOR]

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Small chrysomonads are important bacterivores in aquatic ecosystems with a high molecular diversity compared to low morphological differences observed by light microscopy. The high diversity of these morphologically almost indistinguishable species leads to the question to which extent their functional role in ecosystems differs and how their ecological traits can be defined. The present study investigates the prey size and population growth rate of different chrysomonad species. Eleven phylogenetically well-defined strains representing seven strains of heterotrophic and four strains of mixotrophic chrysomonads were compared. All investigated strains belonged to the same functional group of bacterivorous flagellates, feeding on the same bacteria size range, while population growth rates of chrysomonads depended on nutritional strategy and species-specific differences. We observed a high individual variability of growth rates within a population. Our results point to the necessity to consider not only differences in ecological traits among species but also among specimens within a population. [ABSTRACT FROM AUTHOR]

Summary: Heterotrophic nanoflagellates (HNF) and ciliates are major protistan planktonic bacterivores. The term HNF, however, describes a functional guild only and, in contrast to the morphologically distinguishable ciliates, does not reflect the phylogenetic diversity of flagellates in aquatic ecosystems. Associating a function with taxonomic affiliation of key flagellate taxa is currently a major task in microbial ecology. We investigated seasonal changes in the HNF and ciliate community composition as well as taxa‐specific bacterivory in four hypertrophic freshwater lakes. Taxa‐specific catalyzed reporter deposition‐fluorescence in situ hybridization probes assigned taxonomic affiliations to 51%–96% (average ±SD, 75 ± 14%) of total HNF. Ingestion rates of fluorescently labelled bacteria unveiled that HNF contributed to total protist‐induced bacterial mortality rates more (56%) than ciliates (44%). Surprisingly, major HNF bacterivores were aplastidic cryptophytes and their Cry1 lineage, comprising on average 53% and 24% of total HNF abundance and 67% and 21% of total HNF bacterivory respectively. Kinetoplastea were important consumers of bacteria during summer phytoplankton blooms, reaching 38% of total HNF. Katablepharidacea (7.5% of total HNF) comprised mainly omnivores, with changing contributions of bacterivorous and algivorous phylotypes. Our results show that aplastidic cryptophytes, accompanied by small omnivorous ciliate genera Halteria/Pelagohalteria, are the major protistan bacterivores in hypertrophic freshwaters. [ABSTRACT FROM AUTHOR]

Compositional similarity generally decreases with increasing geographic distance between sites (distance decay of similarity, DDS). Two non‐exclusive mechanisms have been proposed to explain this pattern: increasing differences in environmental conditions and pure spatial effects of dispersal limitation. On regional and global scales, environmental selection is considered the major factor for microbial assemblages, whereas pure spatial effects are generally more profound for larger organisms with limited dispersal ability. We investigated the DDS relationships at a small spatial scale (decimeters ‐ tens of meters) for three groups of benthic organisms differing in body size: diatoms and flagellates (DF), ciliates (CL), and harpacticoids (HA). All groups demonstrated definite DDS relationships. The pure spatial effects were strongest for the smallest‐size protists (DF), relatively weaker for CL and negligible for HA. In contrast, environmental factors (i.e., the differences in sediment properties) were more important for the HA and CL assemblages than for DF assemblages. In addition, we revealed a considerable temporal component of DDS relationships. First, similarity decreased with the time interval between sampling events ("temporal DDS"). Second, the average spatial similarity itself increased with time. These effects were significant for DF and CL only but were weak or undetectable for HA. Thus, our results are opposite to those commonly observed at larger (regional or global) scales. We suppose that the DDS relationships obtained at different spatial scales, despite formal similarity, reflect different phenomena driven by different mechanisms. At the geographical scale, species distribution patterns are mainly driven by long‐distance dispersal processes operated at the population level and dependent on their size‐related traits, which, taken in common, offer the advantage of small‐sized groups. The local‐scale distribution is primarily determined by individual motility and within‐habitat environmental heterogeneity. Small protists are relatively less motile, finely perceived and, therefore, have higher rates of spatial decay. [ABSTRACT FROM AUTHOR]

The first overview of the Laboulbeniomycetes of Ukraine is presented and includes 37 species belonging to 16 genera, 2 families (Laboulbeniaceae and Herpomycetaceae) and 2 orders (Laboulbeniales and Herpomycetales). Among them, Amorphomyces italicus, Botryandromyces heteroceri, Dimorphomyces myrmedoniae, Distolomyces forficulae, Herpomyces stylopygae, H. ectobiae, Hesperomyces virescens, Laboulbenia egens, L. flagellata, L. hyalopoda, L. luxurians, L. thaxteri, L. uncinata, L. vulgaris, Monoicomyces drusillae and M. labiatus are newly reported for Ukraine. All genera above, except for Laboulbenia, are reported for the first time from Ukraine. New records for Cantharomyces italicus, Laboulbenia cristata, L. pedicellata, L. rougetii, Misgomyces dyschirii and Rickia peyerimhoffii are also mentioned. [ABSTRACT FROM AUTHOR]

Microplastics are contaminants of global environmental concern. They can be ingested by a variety of organisms when they enter the food web. Several studies have reported trophic transfer of microplastics from low trophic levels to higher ones. Bioaccumulation has been suggested to occur but few studies have demonstrated it for marine environments. In this article, in controlled laboratory conditions, we exposed filter‐feeder ascidian juveniles to microplastics in the presence or in absence of mixotrophic cryptomonad flagellates. Cryptomonads can efficiently ingest microbeads, and their presence significantly increased the concentration of microplastics in the digestive tract of the ascidians. Our results demonstrate the occurrence of microplastic bioaccumulation in the lower levels of the marine trophic chain and suggest that unicellular organisms can be key actors in microplastic trophic transfer at the microscale level. Research Highlights: •Marine mixotrophic cryptomonad flagellates can ingest microbeads of polystyrene with a diameter of 10 µm. •The copresence of cryptomonads and microbeads significantly increased the microplastics in the digestive tract of filter‐feeding ascidians. [ABSTRACT FROM AUTHOR]

The microorganisms and allelochemicals in Pontederia cordata planting water may have a synergistic inhibitory effect on algae. To study this synergy, an algae-inhibiting organism was isolated and identified, and its growth and feeding characteristics were studied. The organism was identified as Poterioochromonas malhamensis yzs924 based on both its morphology and molecular barcoding employing 18S rDNA gene sequences. The growth and feeding of P. malhamensis were affected by environmental factors and the state of its prey. (1) P. malhamensis is a mixotrophic flagellate. Its heterotrophic growth was the fastest in a wheat grain medium, and its growth rate in this study reached 2.5 day−1. (2) Within a short period of time (2 days), P. malhamensis growth was slower under continuous dark conditions than under alternating light and dark conditions, but it fed on Microcystis aeruginosa more rapidly under dark conditions. (3) High pH was disadvantageous to the growth and grazing of P. malhamensis. When the pH was kept stable at 9, P. malhamensis could not grow continuously. (4) When the initial density of M. aeruginosa was 5 × 107 cells/mL or is in a period of decline, P. malhamensis could not remove all M. aeruginosa. The combined use of P. malhamensis and allelochemicals may represent a method of M. aeruginosa control, but this approach requires further research. [ABSTRACT FROM AUTHOR]

For the first time in the Mekong delta (Vietnam), the abundance and biomass of the main components of the planktonic microbial food web, and namely: bacteria, picophytoplankton, and heterotrophic and phototrophic flagellates were determined; the features of their spatial distribution and the species diversity of heterotrophic flagellates were studied. In this productive polluted tropical river ecosystem, heterotrophic bacteria were large in size and their biomass reached high values characteristic of hypertrophic waters. They made the main contribution (73.8%, on average) to the formation of the total biomass of the planktonic microbial community. The contribution of picophytoplankton and heterotrophic and phototrophic flagellates was 20.5, 3.9, and 1.9%, respectively. Twenty-nine species and forms of heterotrophic flagellates belonging to eight large taxa and a group of uncertain taxonomic position were identified. [ABSTRACT FROM AUTHOR]

Simple Summary: Microalgae are a huge renewable and eco-friendly source of natural compounds, including vitamins, carbohydrates, pigments, sterols and lipids. They have found applications in different industrial sectors, including the pharmaceutical, nutraceutical and cosmeceutical fields. Isochrysis galbana, a marine flagellate belonging to the Haptophyta phylum, thanks to its nutraceutical composition has been proposed as a shellfish diet (Shellfish Diet 1800®) as well as in the composition of cookies, fresh pasta and yogurt. I. galbana powder, extracts or pure molecules have shown interesting bioactivities, such as antioxidant, antidiabetes and antituberculosis, while the antiproliferative activity is mainly related to lung lymphoblasts. In the current study, we aimed to identify metabolic pathways activated in stressful conditions (stationary growth phase) by transcriptomic and bioactivity-guided fractionation. Overall, the results showed antiproliferative activities against melanoma cells, suggesting new possible applications in cancer prevention and treatment. Haptophytes are important primary producers in the oceans, and among the phylum Haptophyta, the flagellate Isochrysis galbana has been found to be rich in high-value compounds, such as lipids, carotenoids and highly branched polysaccharides. In the present work, I. galbana was cultured and collected at both stationary and exponential growth phases. A transcriptomic approach was used to analyze the possible activation of metabolic pathways responsible for bioactive compound synthesis at the gene level. Differential expression analysis of samples collected at the exponential versus stationary growth phase allowed the identification of genes involved in the glycerophospholipid metabolic process, the sterol biosynthetic process, ADP-ribose diphosphatase activity and others. I. galbana raw extracts and fractions were tested on specific human cancer cells for possible antiproliferative activity. The most active fractions, without affecting normal cells, were fractions enriched in nucleosides (fraction B) and triglycerides (fraction E) for algae collected in the exponential growth phase and fraction E for stationary phase samples. Overall, transcriptomic and bioactivity data confirmed the activation of metabolic pathways involved in the synthesis of bioactive compounds giving new insights on possible Isochrysis applications in the anticancer sector. [ABSTRACT FROM AUTHOR]

Summary: Grazing controls bacterial abundances and composition in many ecosystems. In marine systems, heterotrophic flagellates (HFs) are important predators. Assemblages of HFs are primarily formed by species still uncultured; therefore, many aspects of their trophic behaviour are poorly known. Here, we assessed the functional response of the whole assemblage and of four taxa grown in an unamended seawater incubation. We used fluorescently labelled bacteria to create a prey gradient of two orders of magnitude in abundance and estimated ingestion rates. Natural HFs had a half‐saturation constant of 6.7 × 105 prey ml−1, a value lower than that of cultured flagellates and within the range of marine planktonic bacterial abundances. Minorisa minuta was well adapted to low prey abundances and very efficient in ingesting bacteria. MAST‐4 and MAST‐7 were also well adapted to the typical marine abundances but less voracious. In contrast, Paraphysomonas imperforata, a typical cultured species, did not achieve ingestion rate saturation even at the highest prey concentration assayed. Our study, beside to set the basis for the fundamental differences between cultured and uncultured bacterial grazers, indicate that the examined predator taxa have different functional responses, suggesting that they occupy distinct ecological niches according to their grazing strategies and prey preferences. [ABSTRACT FROM AUTHOR]

Hermesinum adriaticum is a rare marine and brackish flagellate that is of considerable interest due to its markable and fossilizable siliceous skeleton. Based on this skeleton, Hermesinum was initially considered a microalga of the Dictyochophyceae (Ochrophyta, Stramenopiles). Later on, it was assigned to the Ebriida due to its similarity to Ebria tripartita. The taxonomic assignment of the Ebriida, however, changed several times until it was placed within the Thecofilosea (Cercozoa, Rhizaria), based on genetic data of E. tripartita. We sequenced the 18S marker gene sequence of Hermesinum and confirm the close relationship of Ebria and Hermesinum. [ABSTRACT FROM AUTHOR]

Mixotrophic flagellates play an important role in connecting the classical food chain and microbial food loop. The feeding characteristics of the mixotrophic flagellate Poterioochromonasmalhamensis have been well studied, but its role as a food source for other large zooplankton is less studied. This study focuses on the physiological and biochemical changes in P. malhamensis when using autotrophy, chemoheterotrophy, and phagotrophy, and the effect of these changes on the feeding ability of one of its predators, the ciliate Paramecium caudatum. The results showed that chemoheterotrophic P. malhamensis had a higher growth rate and larger cell size than autotrophic and phagotrophic P. malhamensis. The biochemical composition of P. malhamensis also varied greatly between the three nutritional modes. The protein, total absolute amino acid, and fucoxanthin contents were highest for autotrophic P. malhamensis, while chemoheterotrophic P. malhamensis had the highest contents of total sugar and total absolute fatty acid. The contents of most biochemical components in phagotrophic P. malhamensis fell between those in autotrophic and chemoheterotrophic P. malhamensis. A feeding experiment showed that the grazing ability of P. caudatum on chemoheterotrophic P. malhamensis was significantly higher than that on phagotrophic P. malhamensis and autotrophic P. malhamensis. This study showed that the transformation of nutritional modes can alter the biochemical composition of the mixotrophic flagellate P. malhamensis and, as a result, affect the grazing ability of its predator P. caudatum. [ABSTRACT FROM AUTHOR]

In estuaries, phytoplankton are faced with strong environmental forcing (e.g. high turbidity, salinity gradients). Taxa that appear under such conditions may play a critical role in maintaining food webs and biological carbon pumping, but knowledge about estuarine biota remains limited. This is also the case in the Elbe estuary where the lower 70 km of the water body are largely unexplored. In the present study, we investigated the phytoplankton composition in the Elbe estuary via metabarcoding. Our aim was to identify key taxa in the unmonitored reaches of this ecosystem and compare our results from the monitored area with available microscopy data. Phytoplankton communities followed distinct seasonal and spatial patterns. Community composition was similar across methods. Contributions of key classes and genera were correlated to each other (p < 0.05) when obtained from reads and biovolume (R2 = 0.59 and 0.33, respectively). Centric diatoms (e.g. Stephanodiscus) were the dominant group - comprising on average 55 % of the reads and 66–69 % of the biovolume. However, results from metabarcoding imply that microscopy underestimates the prevalence of picophytoplankton and flagellates with a potential for mixotrophy (e.g. cryptophytes). This might be due to their small size and sensitivity to fixation agents. We argue that mixotrophic flagellates are ecologically relevant in the mid to lower estuary, where, e.g., high turbidity render living conditions rather unfavorable, and skills such as phagotrophy provide fundamental advantages. Nevertheless, further findings - e.g. important taxa missing from the metabarcoding dataset - emphasize potential limitations of this method and quantitative biases can result from varying numbers of gene copies in different taxa. Further research should address these methodological issues but also shed light on the causal relationship of taxa with the environmental conditions, also with respect to active mixotrophic behavior. [Display omitted] • Centric diatoms/Mediophyceae are key players in the Elbe estuary. • Metabarcoding results overall match with those from microscopy. • Community composition is altered by estuarine features (e.g. tidal currents). • Certain groups (e.g. cryptophytes, picophytoplankton) may be underrated by microscopy. [ABSTRACT FROM AUTHOR]

This essay presents a hypothesis which contends that the development of organismic complexity in the eukaryotes depended extensively on propagation via flagellated and ciliated gametes. Organisms utilizing flagellate and ciliate gametes to propagate their germ line have contributed most of the organismic complexity found in the higher animals. The genes of the flagellum and the flagellar assembly system (intraflagellar transport) have played a disproportionately important role in the construction of complex tissues and organs. The hypothesis also proposes that competition between large numbers of haploid flagellated male gametes rigorously conserved the functionality of a key set of flagellar genes for more than 700 million years. This in turn has insured that a large set (>600) of highly functional cytoskeletal and signal pathway genes is always present in the lineage of organisms with flagellated or ciliated gametes to act as a dependable resource, or "toolkit," for organ elaboration. Also see the video abstract here: https://youtu.be/lC5nC-WOcm8 [ABSTRACT FROM AUTHOR]

The abundances of 17 cytometric groups encompassing four groups of bacteria, three groups of cyanobacteria, six groups of eukaryotic picophytoplankton (<2–3 µm), and four groups of small eukaryotic nanophytoplankton (between 3 and 6 µm) were studied in the Thau Lagoon across different seasonal conditions. Among them, the growth (µ) and mortality rates due to grazing (g) of 12 groups of bacteria, cyanobacteria, and eukaryotic pico- and nanophytoplankton were simultaneously studied in the Thau Lagoon via four dilution experiments across different seasonal conditions. The abundances of heterotrophic flagellates and ciliates and their potential predators were studied and linked to prey mortality. Bacteria were more active than phytoplankton and displayed the highest growth and grazing mortality rates. Most studied groups had g:µ ratios > 1, suggesting that predators efficiently grazed and transferred these preys. Surprisingly, the observed variations in predator abundance across seasons did not necessarily correspond with changes in grazing pressure. The significant positive relationship found between water temperature and bacterial grazing mortality rates and the reverse trend observed for larger eukaryotic prey suggested that warmer water increases small prokaryote transfer to higher trophic levels but disadvantages larger eukaryotic prey transfer. [ABSTRACT FROM AUTHOR]

The Trypanosomatidae family encompasses unicellular flagellates and obligate parasites of invertebrates, vertebrates, and plants. Trypanosomatids are traditionally divided into heteroxenous, characterized by the alternation of the life cycle between an insect vector and a plant or a vertebrate host, including humans being responsible for severe diseases; and monoxenous, which are presumably unique parasites of invertebrate hosts. Interestingly, studies reporting the occurrence of these monoxenous trypanosomatids in humans have been gradually increasing, either associated with Leishmania co-infection, or supposedly alone either in immunocompromised or even more sporadically in immunocompetent hosts. This review summarizes the first reports that raised the hypothesis that monoxenous trypanosomatids could be found in vertebrate hosts till the most current reports on the occurrence of Crithidia spp. alone in immunocompetent human patients. [ABSTRACT FROM AUTHOR]

Until recently, there was no agreement on species delimitation within the morphologically similar chrysophycean genera Uroglena, Uroglenopsis and Urostipulosphaera. In this study, we aimed at a modern taxonomic revision based on the combination of morphological characters (ultrastructure of cysts, cell and colony features) and a multigene phylogeny (SSU, ITS rDNA and rbcL sequences), with ecology taken into account. Of more than 650 explored localities, only approximately one in 10 hosted a viable and detectable population of these colonial chrysophytes at the time of sampling. We established and examined 189 short-term cultures along with single colony isolates, derived mostly from blooming or encysting populations. We obtained the cyst morphology for four species and two lineages of Uroglena, two species of Uroglenopsis, and four species of Urostipulosphaera. A total of 12 resolved lineages could be attributed to previously described species or new species (Uroglena imitata sp. nov., Urostipulosphaera granulata sp. nov.). Based on our molecular analyses and morphological observations, we assign all the previously described Uroglena-like taxa to newly recognized genera and propose a key to identification. Consequently, Uroglena now includes 16 species and two varieties, Uroglenopsis contains four species and Urostipulosphaera encompasses nine species. Within Uroglena and Urostipulosphaera, species are defined by the ultrastructure of their cysts. On the contrary, as Uroglenopsis has simple cysts, species are defined by cell and colony characteristics. [ABSTRACT FROM AUTHOR]

This 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. [ABSTRACT FROM AUTHOR]

We describe and illustrate Selaginella rachipterygia Valdespino, Cornejo & C. López as a new species found on the inter-Andean eastern slopes of the Central Cordillera of Colombia and on the slopes on both sides of the Andes of Ecuador and compare it to S. flagellata Spring. Selaginella rachipterygia is notable for its often flagelliform branch, stem, and strobilus tips, which are often gemmiferous, and by its lateral leaves perpendicular to the main stems below the first branches, which give the stems the appearance of having wings. In addition, we document the expanded distribution range of S. simplex Baker to include Panama and Ecuador. Finally, we contrast S. simplex with the similarly small-sized species S. correae Valdespino and S. minima Spring, which overlap either in part of or throughout their distribution ranges. [ABSTRACT FROM AUTHOR]

Bacillus subtilis is capable of swarming motility on semisolid surfaces. Here we characterize the swarming phenotype of a mutant in the gene of unknown function, yozG in the undomesticated strain 3610. The yozG mutant was unable to swarm. Swarming could be restored to the mutant by overexpression of the swarming regulator gene swrA or by overexpression of the flagella and chemotaxis operon. In addition, we were able to isolate two genetic suppressors of the yozG mutant that could also restore swarming. yozG is necessary for swarming in B. subtilis and likely acts upstream of the swarming regulator, SwrA. [ABSTRACT FROM AUTHOR]

Marine heterotrophic flagellates (HFs) form a diverse and ecologically relevant functional group of bacterial grazers and nutrient remineralizers in oceanic waters. Despite playing a crucial role in marine biogeochemical cycles, there is still a lack of information on which specific taxa dominate HF assemblages and what are their patterns of distribution in a global context. In the present work, we addressed this issue by analyzing amplicon sequencing data sets retrieved from samples taken in tropical and subtropical oceanic regions at depths from surface to 4000 m. Only a few dozens of widespread taxa, mostly affiliating to MAST clades, Picozoa, Bicosoecida and Chrysophyceae, seemed to dominate surface HF assemblages. The majority of these dominant HFs were present at relatively constant abundances, while others were influenced by temperature or displayed a patchy distribution. In the deep ocean, only a handful of taxa belonging to Bicosoecida and Chrysophyceae, together with Diplonemea and Kinetoplastida, explained most of the HF signal. Co‐occurrence networks between HF and prokaryotic taxa at the surface ocean revealed two main clusters influenced by temperature that did not seem to show specific patterns of interaction. However, some correlations emerged outside these thermal groups that could represent new prey–predator interactions. Overall, we identified the putatively most ecologically relevant HF taxa in the ocean, which become promising targets for further experimental and genomic studies. [ABSTRACT FROM AUTHOR]

The abundance, biomass, size structure of small photosynthetic flagellates (SPF; 3–10 µm), chlorophyll a (Chl a), and the contribution of SPF to the total phytoplankton biomass were studied in Onega Bay of the White Sea in September 2019. The Chl a concentration in the surface water layer of the bay varies from 0.36 to 0.83 mg/m3. The contribution of photosynthetic algae to the total phytoplankton biomass ranges from 79 to 83%. The abundance and biomass of SPF in the photic layer varies from 0.04 × 109 to 0.22 × 109 cells/m3 and from 0.64 to 6.4 mg C/m3, respectively. Flagellates with a cell size of 6–10 µm dominate in the total SPF biomass and their share averages 82%. The SPF contribution to the total phytoplankton biomass in Onega Bay varies from 6 to 58% and does not depend on the phase of the tidal cycle. The obtained data on the SPF abundance evidenced that this group of protists plays a significant role in phytoplankton communities, and their estimate results in higher values of the total phytoplankton biomass of the White Sea in the fall compared to data obtained earlier. [ABSTRACT FROM AUTHOR]

Virophages can parasitize giant DNA viruses and may provide adaptive anti-giant virus defense in unicellular eukaryotes. Under laboratory conditions, the virophage mavirus integrates into the nuclear genome of the marine flagellate Cafeteria burkhardae and reactivates upon superinfection with the giant virus CroV. In natural systems, however, the prevalence and diversity of host-virophage associations has not been systematically explored. Here, we report dozens of integrated virophages in four globally sampled C. burkhardae strains that constitute up to 2 % of their host genomes. These endogenous mavirus-like elements (EMALEs) separated into eight types based on GC-content, nucleotide similarity, and coding potential and carried diverse promoter motifs implicating interactions with different giant viruses. Between host strains, some EMALE insertion loci were conserved indicating ancient integration events, whereas the majority of insertion sites were unique to a given host strain suggesting that EMALEs are active and mobile. Furthermore, we uncovered a unique association between EMALEs and a group of tyrosine recombinase retrotransposons, revealing yet another layer of parasitism in this nested microbial system. Our findings show that virophages are widespread and dynamic in wild Cafeteria populations, supporting their potential role in antiviral defense in protists. [ABSTRACT FROM AUTHOR]

Bleomycin, an antineoplastic, glycopeptide antibiotic is commonly used to treat several malignancies, in particular, lymphomas, testicular carcinoma, and squamous cell carcinoma. As bleomycin degradation by enzyme hydrolase is less in the skin and lungs, a higher likelihood of cutaneous toxicity exists. We present a case of bleomycin-induced flagellate dermatitis, a characteristic cutaneous eruption that occurred as a result of bleomycin administration. A 58-year-old man with Stage 4 diffuse large B-cell lymphoma presented with sudden onset of skin lesions that appeared five weeks after initiation of third-line bleomycin-containing palliative chemotherapy. The whip-like, linear, hyperpigmented plaques were indicative of flagellate dermatitis. We aim to present the natural course of bleomycin flagellate dermatitis and its natural course. [ABSTRACT FROM AUTHOR]

The morphological ontogeny of Galumna flagellata Willmann, 1925 is described and illustrated. The juveniles of this species are light brown, with prodorsal setae of medium size or long and barbed, and bothridial seta clavate. The larva has 12 pairs of gastronotal setae, most of the medium size and barbed, of which seven (d-, l-series, h1) are located on gastronotal shield, nymphs have 15 pairs, mostly short setae, of which 10 (d-, l-, h-series, p1) are located on the gastronotal shield, setae of c-series are inserted on individual sclerites. In all juveniles, the typical galumnid humeral organ is absent, but a porose area is present in this location, which is unique in Galumna. [ABSTRACT FROM AUTHOR]

One genus and two new species of linyphiid spiders are described from Thailand: Protopalpus, new genus, with Protopalpus kurku, new species, as the type species, and Cyphonetria flagellata, new species. The new genus is described based on the sole male, being characterised by a simple and primitive structure of the palp. The taxonomic position of the genus Cyphonetria Millidge, 1995 within the subfamilies of Linyphiidae is discussed. New data on the distribution of some linyphiid spiders in Southeast Asia are given. Nasoonaria sinensis Wunderlich & Song, 1995 is recorded from Vietnam and Myanmar for the first time, Neriene strandia (Blauvelt, 1936) is new to the fauna of Laos. [ABSTRACT FROM AUTHOR]

Snails of the genus Pomacea, commonly known as swamp snails, are of great relevance from an ecological, trophic, and nutritional point of view. The objective of this research was to prepare pickled snail marinade using Pomacea flagellata meat from Tabasco, Mexico. Bromatological analyses were conducted to know the escabeche's chemical composition, as well as microbiological analyses for safety purposes and sensory tests to clarify consumer acceptability. The P. flagellata snail-based marinade was found to be highly safe (total coliform and yeast, 0 NMP g-1 and 0 UFC g-1, respectively). Results confirm that swamp snail meat has average levels of protein (11.3 ± 2.6%) and low-fat levels (4.5 ± 1.1%). In conclusion, the marinade made from pickled P. flagellata snail had a high degree of safety and nutritional value and was greatly accepted by consumers. [ABSTRACT FROM AUTHOR]