Nitrogen and phosphorus stress as a tool to induce lipid production in microalgae.

Microalgae, capable of accumulating large amounts of lipids, are of great value for biodiesel production. The high cost of such production stimulates the search for cultivation conditions that ensure their highest productivity. Reducing the content of nitrogen and phosphorus in the culture medium is widely used to change the content and productivity of lipids in microalgae. Achieving the right balance between maximum growth and maximum lipid content and productivity is the primary goal of many experimental works to ensure cost-effective biodiesel production from microalgae. The content of nitrogen and phosphorus in nutrient media for algal cultivation after converted to nitrogen (-N) and phosphorus (-P) lies in an extensive range: from 0.007 g L- 1 to 0.417 g L- 1 and from 0.0003 g L- 1 to 0.227 g L- 1 and N:P ratio from 0.12:1 to 823.33:1. When studying nutritional stress in microalgae, no single approach is used to determine the experimental concentrations of nitrogen and phosphorus. This precludes the possibility of correct interpretation of the data and may lead to erroneous conclusions. This work results from the systematisation of information on using nitrogen and phosphorus restriction to increase the lipid productivity of microalgae of different taxonomic and ecological groups to identify future research directions. The results of 301 experiments were included in the analysis using the principal components method. The investigation considered various divisions and classes: Cyanobacteria, Rhodophyta, Dinophyta, Haptophyta, Cryptophyta, Heterokontophyta/Ochrophyta (Bacillariophyceae, Eustigmatophyceae, Xanthophyceae), Chlorophyta, and also the ratio N:P, the time of the experiment, the light intensity during cultivation. Based on the concentrations of nitrogen and phosphorus existing in various nutrient media, a general scheme for designating the supply of nutrient media for nitrogen (as NO3- or NH4+, N g L- 1) and phosphorus (as РO4-, P g L- 1) has been proposed: replete -N (˃0.4 g L- 1), moderate -N (0.4-0.2), moderate N-limitation (0.19-0.1), strong N-limitation (˂0.1), without nitrogen (0), replete -Р (˃0.2), moderate -P (0.2-0.02), moderate P-limitation (0.019-0.01), strong P-limitation (˂0.01), without phosphorus (0).

The Influence of Solid and Liquid Systems In Vitro on the Growth and Biosynthetic Characteristics of Microshoot Culture of Spiraea betulifolia ssp. aemiliana.

The paper focuses on the growth dynamics and biosynthetic characteristics of the microshoot culture of Spiraea betulifolia ssp. aemiliana obtained in vitro in agar-solidified and liquid media. Microshoots cultured in either type of media showed similar growth dynamics. The most active culture growth was observed from day 35 to day 60. A comparative analysis of the contents of flavonoids and phenol carboxylic acids showed a higher level of phenol carboxylic acids (5.3-6.84%) and a stronger 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity (half-maximal inhibitory concentration: 341 µg/mL) in S. betulifolia ssp. aemiliana microshoots grown in the liquid medium compared to the microshoots cultured in the solid medium. The flavonoid content of the cultured microshoot did not depend on the consistency of the medium. High-performance liquid chromatography (HPLC) was employed to study the profile and levels of phenolic compounds in microshoots, intact plants, and ex vitro-acclimated S. betulifolia ssp. aemiliana plants. The concentration of kaempferol glycosides was found to be higher in microshoots (1.33% in the solid medium, 1.06% in the liquid medium) compared to intact plants and ex vitro-acclimated plants. Thus, the microshoots of S. betulifolia ssp. aemiliana cultured in the liquid medium rapidly increase their biomass and are an inexpensive promising source of biologically active antioxidant substances, mainly phenol carboxylic acids and kaempferol glycosides.

Phylogeny and fatty acid profiles of Aliinostoc vietnamicum sp. nov. (cyanobacteria) from the soils of Vietnam.

A new cyanobacterial species of Aliinostoc, A. vietnamicum sp. nov., is recorded in the tropical forest soil from the Cát Tiên National Park, Vietnam. The analysis is based on morphological characters, 16S rDNA phylogeny, ITS secondary structure, and fatty acid composition analysis. Aliinostoc vietnamicum differed from the other species of the genus by the size and shape of vegetative cells, size of akinetes and heterocytes, and presence of granular polyphosphate inclusions in vegetative cells. The evolutionary distance matrix based on the 16S rRNA gene shared 96.2-98.2% similarities with other Aliinostoc sequences. The phylogeny inferred by maximum likelihood and Bayesian inference placed A. vietnamicum in the Aliinostoc clade, within the Nostocaceae. For the first time, fatty acid composition analysis was obtained for a member of the genus Aliinostoc with cultivation time experiments. α-linolenic (27.54-37.75%), palmitic (13.87-22.65%), and stearic (10.08-20.27%) acids were the dominant fatty acids when cultured during the exponential growth phase, as well as during stationary. This is the first finding of a strain with such a high content of stearic acid among cyanobacteria with Nostoc-like morphology.

A New Species of Freshwater Algae Nephrochlamys yushanlensis sp. nov. (Selenastraceae, Sphaeropleales) and Its Lipid Accumulation during Nitrogen and Phosphorus Starvation.

The new species Nephrochlamys yushanlensis sp. nov. is described from a freshwater plankton sample. A comparison of morphology, 18S rDNA gene and ITS2 sequences, and fatty acid profiles showed that the novel strain represents a new lineage within the genus Nephrochlamys. For the first time with a member of the Selenastraceae, experiments with phosphate and nitrate deprivation were conducted to evaluate changes in biomass, lipid and triacylglycerol (TAGs) accumulation, and composition of fatty acids. Biomass dry weight under simultaneous nitrogen and phosphorus depletion was 1.73 g · L-1 , which is significantly lower than the 2.41 g · L-1 observed in the control. All conditions of nutrient restriction significantly increased the lipid content in comparison with the control. The largest increase in the total lipid content, reaching 58.64% DW per cell at the end of cultivation, occurred with nitrogen deficiency. Significant increases in TAGs content (to 23.69% and 21.74%, respectively) occurred in phosphorus- and nitrogen-depleted conditions in comparison to the control (16.90%). Oleic (49.8-64.1%), palmitic (21.1-22.7%), and linoleic (8.6-10.3%) acids were the dominant fatty acids when cultured on standard BBM medium, as well as with the shortage of nutrients. Phosphorus deprivation as well as absence of both nitrogen and phosphorus led to the appearance of FAMEs α-linolenic (1.5-4.1%) and stearidonic (1.0-1.8%) acids. In general, FAME profiles revealed that the relative percentage of saturated and monounsaturated fatty acids increased (88.9% of total fatty acids) in nitrogen-depletion conditions, suggesting this strain may be suitable for biodiesel production.

Investigation of Chemical Constituents of Eranthis longistipitata (Ranunculaceae): Coumarins and Furochromones.

Aqueous-ethanol extracts (70%) from the leaves of Eranthis longistipitata Regel. (Ranunculaceae Juss.)-collected from natural populations of Kyrgyzstan-were studied by liquid chromatography with high-resolution mass spectrometry (LC-HRMS). There was no variation of the metabolic profiles among plants that were collected from different populations. More than 160 compounds were found in the leaves, of which 72 were identified to the class level and 58 to the individual-compound level. The class of flavonoids proved to be the most widely represented (19 compounds), including six aglycones [quercetin, kaempferol, aromadendrin, 6-methoxytaxifolin, phloretin, and (+)-catechin] and mono- and diglycosides (the other 13 compounds). In the analyzed samples of E. longistipitata, 14 fatty acid-related compounds were identified, but coumarins and furochromones that were found in E. longistipitata were the most interesting result; furochromones khelloside, khellin, visnagin, and cimifugin were found in E. longistipitata for the first time. Coumarins 5,7-dihydroxy-4-methylcoumarin, scoparone, fraxetin, and luvangetin and furochromones methoxsalen, 5-O-methylvisammioside, and visamminol-3'-O-glucoside were detected for the first time in the genus Eranthis Salisb. For all the above compounds, the structural formulas are given. Furthermore, detailed information (with structural formulas) is provided on the diversity of chromones and furochromones in other representatives of Eranthis. The presence of chromones in plants of the genus Eranthis confirms its closeness to the genus Actaea L. because chromones are synthesized by normal physiological processes only in these members of the Ranunculaceae family.

Gogorevia, a New Monoraphid Diatom Genus for Achnanthes exigua and Allied Taxa (Achnanthidiaceae) Described on the Basis of an Integrated Molecular and Morphological Approach.

A new diatom genus, Gogorevia, is described on the basis of an integrated molecular and morphological investigation. Two species are described from Vietnam: the generitype, G. rinatii sp. nov., and G. ovalis sp. nov. These species share many morphological features with Achnanthes exigua and allied taxa that were previously transferred to the genera Achnanthidium or Lemnicola. Our current molecular investigation shows that Gogorevia is distinct and phylogenetically removed from the above-mentioned genera. Morphologically, Gogorevia differs from Achnanthidium and Lemnicola by the shape of the valves, possessing uniseriate striae, raphe morphology, and the presence of an evident sternum. The recently described species Lemnicola uniseriata is transferred to Gogorevia on the basis that it possesses the same morphological features and phylogenetic position as other members of the genus.

Fatty Acid Content and Profile of the Novel Strain of Coccomyxa elongata (Trebouxiophyceae, Chlorophyta) Cultivated at Reduced Nitrogen and Phosphorus Concentrations.

A novel freshwater strain of Coccomyxa elongata (MZ-Ch64) was isolated from the Zaporizhia region, Ukraine. The identification was based on the phylogenetic analysis of SSU rDNA gene and ITS1-5.8S rDNA-ITS2 region and predicted secondary structure of the ITS2. Phylogenetic analysis placed this strain in the Coccomyxa group, within the class Trebouxiophyceae. The novel strain MZ-Ch64 formed a strongly supported lineage closest with C. elongata. The MZ-Ch64 strain differed from the morphological description of the species by the size of vegetative cells and absence of small mucilaginous caps at one end of the cell. A number of experiments with different concentrations of phosphate and nitrate were conducted to evaluate changes in the resulting fatty acid profiles and biomass productivity. The fatty acid profile and total fatty acids varied significantly under different nutrient deficiencies. The dominant fatty acid during cultivation on standard BBM medium, as well as in phosphorus-depleted conditions, was oleic acid (to 48.0%-54.6% of total fatty acids). Absence of nitrogen alone, and absence of both nitrogen and phosphorus, led to an increase of palmitic acid (to 24.7%-25.6%), cis-7-hexadecenoic acid (to 14.8%) and α-linolenic acid (to 9.1%-10.1%) in comparison with the control sample. The greatest variation was found for oleic acid (31.9%-54.6%). Thus, this strain can be considered as a potential producer of oleic acid or cis-7-hexadecenoic and α-linolenic acids for biotechnological applications.

Description of a new diatom genus Dorofeyukea gen. nov. with remarks on phylogeny of the family Stauroneidaceae.

Type material of Navicula kotschyi was studied, and this species was transferred to Dorofeyukea gen. nov. as D. kotschyi comb. nov. Dorofeyukea was described on the basis of DNA sequence and morphological data. Additional species assigned to this genus that were previously included in Navicula include: D. ancisa comb. nov., D. grimmei comb. nov., D. ivatoensis comb. nov., D. orangiana comb. nov., D. rostellata comb. nov. & stat. nov., D. savannahiana comb. nov., D. tenuipunctata comb. nov., and D. texana comb. nov. All Dorofeyukea species share the same morphological features, including having a narrow stauroid fascia surrounded by 1-3 irregularly shortened striae, uniseriate, and weakly radiate striae, circular, or rectangular puncta in the striae that are covered internally by dome-shaped hymenes, presence of a pseudoseptum at each apex and absence of septa. Partial DNA sequences of SSU and rbcL loci show Dorofeuykae belongs to the clade of stauroneioid diatoms together with Stauroneis, Prestauroneis, Craticula, Karayevia, Madinithidium, Fistulifera, Parlibellus, and, possibly, Schizostauron. A new species from the monoraphid genus Madinithidium, M. vietnamica sp. nov., was described based on valve and chloroplast morphology as well as DNA sequence data.

Reassessment of pore occlusion in some diatom taxa with re-evaluation of Placoneis Mereschkowsky (Bacillariophyceae: Cymbellales) and description of two new genera.

In this article, the history and taxonomy of Placoneis gastrum, the type species of the genus Placoneis, was discussed. We investigated the structure of pore occlusions in Placoneis and related genera. As a result, we propose a new classification for tectulum-like types of pore occlusions. The new classification is congruent with previously-published and newly-constructed phylogenies based on molecular data. Based on the different structures of the pore occlusions, species of Placoneis are transferred to Witkowskia gen. nov. Hence, 168 new combinations are introduced. A new diatom species, with a similar morphology to Placoneis flabellata, was discovered in Bac Kan Province, Vietnam. It is described in this article as Chudaevia densistriata sp. nov. Placoneis flabellata is transferred to Chudaevia gen. nov. We also illustrate Placoneis flabellata herein and compare it to Chudaevia densistriata sp. nov. An unknown diatom, similar to Placoneis coloradensis, was discovered in Chukotka, Russia. It is introduced as Placoneis elinae sp. nov. below. Additionally, we discuss the distribution of some species of Witkowskia gen. nov. and Chudaevia gen. nov.

A new species of genus Crenotia (Bacillariophyta) from Tibet, China.

During the investigation of the freshwater diatoms from Tibet, a monoraphid species was observed from a hot spring near Anduo County, located on a plateau in the central portion of Tibet. This species shares the diagnostic features of Crenotia, such as the valve bent along the transapical axis, striae uniseriate to biseriate from centre to the apices and areolae with special structures located at the end of each stria. We compared the morphological characters of this new species with the others in this genus and show it to be new; it is named Crenotiatibetiasp. nov. This species has small valves with slightly protracted ends with nearly capitate apices, lanceolate axial area, central area unilaterally expanded to the margin, striae uniseriate to biseriate, but, in some valves, the striae are only uniseriate. Areolae are round small to irregular in shape and, at the end of each stria, there is a horseshoe-shaped areola present. Observations of developing valves show all the striae begin biseriate, then they become covered by silica to form uniseriate striae. Comparisons are made amongst the species in this genus and with genera assigned to the Achnanthidiaceae.

The Co-Evolution Aspects of the Biogeochemical Role of Phytoplankton in Aquatic Ecosystems: A Review.

In freshwater and marine ecosystems, the phytoplankton community is based on microalgae and cyanobacteria, which include phylogenetically very diverse groups of oxygenic photoautotrophs. In the process of evolution, they developed a wide range of bio(geo)chemical adaptations that allow them to effectively use solar radiation, CO2, and nutrients, as well as major and trace elements, to form O2 and organic compounds with a high chemical bond energy. The inclusion of chemical elements in the key processes of energy and plastic metabolism in the cell is determined by redox conditions and the abundance and metabolic availability of elements in the paleoenvironment. Geochemical evolution, which proceeded simultaneously with the evolution of biosystems, contributed to an increase in the number of metals and trace elements acting as cofactors of enzymes involved in metabolism and maintaining homeostasis in the first photoautotrophs. The diversity of metal-containing enzymes and the adaptive ability to replace one element with another without losing the functional properties of enzymes ensured the high ecological plasticity of species and allowed microalgae and cyanobacteria to successfully colonize a wide variety of habitats. In this review, we consider the main aspects of the modern concepts of the biogeochemical evolution of aquatic ecosystems and the role of some metals in the main bioenergetic processes in photosynthetic prokaryotes and eukaryotes. We present generalized data on the efficiency of the assimilation of key nutrients by phytoplankton and their importance in the cycle of carbon, silicon, nitrogen, phosphorus, sulfur, and iron. This article presents modern views on the evolutionary prerequisites for the formation of elemental signatures in different systematic groups of microalgae, as well as the possibility of using the stoichiometric ratio in the study of biological and geochemical processes in aquatic ecosystems.

Genetic Markers for Metabarcoding of Freshwater Microalgae: Review.

The metabarcoding methods for studying the diversity of freshwater microalgae and routine biomonitoring are actively used in modern research. A lot of experience has been accumulated already, and many methodological questions have been solved (such as the influence of the methods and time of sample conservation, DNA extraction and bioinformatical processing). The reproducibility of the method has been tested and confirmed. However, one of the main problems-choosing a genetic marker for the study-still lacks a clear answer. We analyzed 70 publications and found out that studies on eukaryotic freshwater microalgae use 12 markers (different nuclear regions 18S and ITS and plastids rbcL, 23S and 16S). Each marker has its peculiarities; they amplify differently and have various levels of efficiency (variability) in different groups of algae. The V4 and V9 18S and rbcL regions are used most often. We concentrated especially on the studies that compare the results of using different markers and microscopy. We summarize the data on the primers for each region and on how the choice of a marker affects the taxonomic composition of a community.

Taxonomy and Distribution of the Genus Sellaphora Mereschowsky (Bacillariophyceae: Sellaphoraceae) in Aquatic Ecosystems of Mongolia.

During our investigation, 28 species belonging to the genus Sellaphora Mereschowsky were found in different types of water bodies and streams in Mongolia. Of these, 14 species have already been described and/or shown earlier in the flora of Mongolia, and we found 14 species for the first time. One new taxonomic combination has been proposed: Sellaphora glomus (J.R. Carter and A.E. Bailey-Watts) Glushchenko and Kulikovskiy comb. nov. One species is proposed for description as new to science: Sellaphora dorofeyukae Glushchenko and Kulikovskiy sp. nov. All species were illustrated with original light micrographs, and a number of species were also illustrated with scanning electronic photographs. The distribution of the identified species within Mongolia and the world is discussed.

Antioxidant Status and Biotechnological Potential of New Vischeria vischeri (Eustigmatophyceae) Soil Strains in Enrichment Cultures.

The functional state of enrichment cultures of the Eustigmatophycean strains Vischeria vischeri MZ-E3 and MZ-E4 after 25-day cultivation in the BBM medium was studied. The concentrations of chlorophyll a, total carotenoids, protein, vitamins A and E, fatty acid peroxidation product content, an antioxidant enzyme, and succinate dehydrogenase activity were measured. MZ-E3 succinate dehydrogenase activity was significantly higher by 2.21 times; the MZ-E4 strain had 2.94 times higher glutathione peroxidase activity. The MZ-E3 antioxidant activity index and the MZ-E3 unsaturation of fatty acids were 1.3 and 1.25 times higher than the MZ-E4. The retinol and α-tocopherol content of the MZ-E3 was 28.6% and 38.76% higher than MZ-E4. The main fatty acid profile differences were the 3.46-fold and 3.92-fold higher stearic and eicosapentaenoic acid content in the MZ-E4 biomass. MZ-E3 had higher antioxidant, energy, and metabolic and photosynthetic status than MZ-E4. The antioxidant status of the studied strains showed the dependence of the adaptive mechanisms of each, associated with differences in the ecological conditions of the biotopes from which they were isolated. These strains are promising for producing α-tocopherol and biomass enriched with omega-3 and omega-6 fatty acids.

New and Interesting Taxa from the Diatom Genus Gomphonema Ehrenberg in Shallow, Nearshore Sites on the Eastern Coast of Lake Baikal.

During this investigation, sixteen species from the genus Gomphonema were found in a shallow bay (near Oimur, Kabansky District) located on the eastern shore of Lake Baikal. Eleven of these taxa have been described previously. Five species are described as new to science. We provide ecological information about these Gomphonema species, including their distribution within and outside Lake Baikal, and compare and contrast the new taxa with morphologically similar congeners. The diversity of morphologies present in Lake Baikal among the Gomphonema species suggests there has been both in-lake speciation as well as the introduction of various groups of species. The idea that Lake Baikal may support a high number of endemics by their partitioning niches based on depth is supported by the different groups of gomphonemoid diatoms present.

The Genus Pinnularia Ehrenberg (Bacillariophyta) from the Transbaikal Area (Russia, Siberia): Description of Seven New Species on the Basis of Morphology and Molecular Data with Discussion of the Phylogenetic Position of Caloneis.

Seven Pinnularia species from the Transbaikal area, Russia, are described as new for science. These are P. baicalgenkalii, P. baicalflexuosa, P. microfrauenbergiana, P. pergrunowii, P. siberiosinistra, P. baicalodivergens, and P. baicalislandica. All species are described by original LM and SEM microphotographs and molecular phylogeny. We provide comparisons between the taxa and document variability in the features found in the species. The number of Pinnularia species in the Transbaikal area is the largest number of species of the genus anywhere in the world.

Gandhia gen. nov.-A New Diatom Genus with Unusual Morphology Split Off from the Genus Navicula Bory.

A new naviculoid diatom genus, Gandhia gen. nov., was described based on a detailed morphological investigation using light and scanning electron microscopy. Gandhia obtecta (Jüttner and Cox) Kulikovskiy, Glushchenko, Iurmanov, M.Thacker, B.Karthick and Kociolek comb. nov. was previously described as a member of the genus Navicula Bory sensu lato. This species differs from other species in the genus Navicula s.l. by the presence of an internal siliceous lamina covering the alveoli and forming the image of longitudinal lines on either side of the axial area, visible in LM. The presence of this siliceous lamina is similar to laminae in genera such as Pinnularia and Gomphoneis. This unusual morphology is not typical for Navicula sensu stricto, as previously noted by other scientists. Additional investigation of Gandhia obtecta comb. nov. and Gandhia ramosissimoides (H.P. Gandhi) Kulikovskiy, Glushchenko, M.Thacker, B.Karthick and Kociolek comb. nov. from waterbodies of the Western Ghats and the Himalayan region was conducted. Comparison with other species with the same morphological features included two additional species in the genus, namely, Gandhia jakovljevicii (Hustedt) Kulikovskiy, Glushchenko, M.Thacker, B.Karthick, and Kociolek comb. nov. and Gandhia lucida (Pantocsek) Kulikovskiy, Glushchenko, M.Thacker, B.Karthick and Kociolek comb. nov. We discuss the biogeographic patterns of the species, including disjuncts between Europe and Asia.

Is Sellaphora the New Navicula? Cymbosellaphora (Cymbellales), a New Genus Based on Taxa Previously Assigned to Sellaphora.

A new diatom genus Cymbosellaphora Kulikovskiy, Glushchenko, Genkal and Kociolek gen. nov., was described with species Cymbosellaphora vietnamensis Glushchenko, Kulikovskiy and Kociolek sp. nov. C. vietnamensis sp. nov. was described from Vietnam and characterized by the presence of morphological features such as valves with naviculoid symmetry, slight dorsiventrality, the presence of tectula as pore occlusions, uniseriate striae, and a very broad mantle. Four species were transferred to the new genus. These are C. absoluta comb. nov., C. circumborealis comb. nov., C. geisslerae comb. nov., and C. laterostrata comb. nov. Previously, these species were members of genera Navicula Bory, Sellaphora Mereschkowsky, and Naviculadicta Lange-Bertalot. The taxonomic history of these species and genera are discussed. The tectulum is known only from the cymbelloid diatoms, and our new genus is placed within the Cymbellaceae. The presence of a tectulum demonstrates that these species cannot be placed in Sellaphora, as indicated in the literature. The recent proposal to transfer a large number of species with different morphologies to the genus Sellaphora is also discussed. Additionally, we compare pore occlusions with tectula between different genera of the Cymbellaceae with naviculoid symmetry.

LC-HRMS for the Identification of Quercetin and Its Derivatives in Spiraea hypericifolia (Rosaceae) and Anatomical Features of Its Leaves.

Spiraea hypericifolia L. is affiliated with the section Chamaedryon Ser. of the genus Spiraea L. (Rosaceae). Similar to many other Spiraea species, S. hypericifolia most often accumulates flavonols among other flavonoids, in particular quercetin and its derivatives. An ethanol-water extract from the aerial part of S. hypericifolia collected in the vicinity of the Ilyichovo settlement (Krasnoyarsk Krai, Russia) was analyzed by liquid chromatography with high-resolution mass spectrometry. Primary and secondary metabolites were found in the extract; structural interpretation consistent with quercetin and its derivatives was proposed for 10 of them. Major compounds were various glycosides of quercetin containing glucose (four compounds), galactose (one compound), xylose (two compounds), arabinose (one compound), or rutinose (one compound) as a carbohydrate residue. Isorhamnetin and 3-O-methylquercetin-3'-O-ß-D-glucopyranoside were identified among methyl-containing compounds. The latter compound and reynoutrin, rhamnetin-3-O-ß-D-xylopyranosyl-ß-D-glucopyranoside, and quercetin-3-O-(6″-O-malonyl)-ß-D-glucoside have not been previously found in S. hypericifolia. Data on the presence of quercetin and its derivatives in the extract of S. hypericifolia expand the understanding of the possible practical use of this plant. In addition, the microscopic features of S. hypericifolia leaves were studied. The diagnostic features of the leaf blade necessary for the authentication of raw materials were revealed: straight-walled epidermis cells, stomata located on both sides of the leaf blade (amphistomatic type), two types of trichomes, and wrinkled cuticula with nodi. The main anatomical diagnostic features of the leaves of S. hypericifolia were determined, which makes it possible to assess the authenticity of the raw material.

Chrysosphaerella septentrionalis sp. nov. (Chrysophyceae, Chromulinales), a New Species from the Arctic Including the Description of Chrysosphaerellaceae, fam. nov.

A new species, Chrysosphaerella septentrionalis, is described from a peat bog located on the bank of the Paz River (Pasvik Nature Reserve, Murmansk Region, Russia). Scale ultrastructure was studied using a scanning electron microscope. Morphologically, C. septentrionalis seems to closely resemble C. longispina. However, C. septentrionalis possesses subcircular scales in addition to the oval scales, and they are much smaller than in C. longispina. We suppose that C. septentrionalis is the first pseudocryptic species within the C. longispina complex. Additionally, we proposed an infrageneric classification of Chrysosphaerella based on the scale structure and divided the genus into three sections: Chrysosphaerella, Brevispinae sect. nov. and Septispinae sect. nov. The formal description of a new family Chrysosphaerellaceae fam. nov. is also provided.