High diversity of silica-scaled chrysophytes was recorded in the Barguzin River mouth and the Selenga River delta. Their flora was represented by 66 species and intra-specific taxa: Chrysosphaerella — 2, Paraphysomonas — 8, Clathromonas — 5, Spiniferomonas — 8, Mallomonas — 29, and Synura — 14. Eight taxa of silica-scaled chrysophytes were observed for the first time in Russia: Chrysosphaerella rotundata, Mallomonas doignonii, M. trummensis, M. corymbosa, Clathromonas poteriophora, Paraphysomonas acuminata acuminata, P. vulgaris, and Synura laticarina. In May, we found scales of Mallomonas striata with morphologically changed structure in the mouth of the Barguzin River and Srednyaya Channel of the Selenga River delta. The flora of silica-scaled chrysophytes studied differs from one tributary to another. We observed only 52 species in the Selenga River delta, whereas in the Barguzin River mouth we identified 35 species. These large rivers affect the flora of Lake Baikal diversifying silica-scaled chrysophytes in its southern and central basins. The total list of species and intra-specific taxa in the Selenga River delta, Barguzin River mouth, and in Lake Baikal includes 72 taxa. Therefore, this area may be considered as a “hotspot” of silica-scaled chrysophytes together with three hotspots observed worldwide earlier.

South Ural is a territory with a unique geographical position and heterogeneous natural conditions. Unexplored biodiversity of the terrestrial cyanobacteria of this territory is very high. We undertook a floristic study covering all botanical-geographical zones of the Bashkiria and Bredinskiy district of the Chelyabinsk region. In a total of 85 soil samples collected, 56 species of cyanobacteria were identified. The number of cyanobacteria was highest in the boreal-forest zone (39 species) and notably lower in the other zones (18, 29, and 24 species for broad-leaved forest, forest steppe and steppe regions, respectively). Leptolyngbya voronichiniana, Leptolyngbya foveolarum, cf. Trichocoleus hospitus, Pseudophormidium hollerbachianum, Nostoc cf. punctiforme, Microcoleus vaginatus, Phormidium breve, Phormidium dimorphum, Phormidium corium, and Leptolyngbya cf. tenuis were detected in all studied zones. Trichormus variabilis and Cylindrospermum majus were detected in the forest zone, Phormidium ambiguum was typical for forest-steppe and steppe zones, Pseudophormidium hollerbachianum and Nostoc cf. commune were most abundant in the steppe. Humidity and heterogeneity of the substrate were likely the most important factors influencing terrestrial cyanobacteria diversity. For full understanding of the biodiversity of cyanobacteria in the South Urals, future molecular-genetic research is necessary.

The algae which cause snow blooming remain poorly studied in the northern regions of the Eastern Europe. However, the process is widely observed, especially, in the mountain regions. The growth of cryophilic algae has a strong fascilitating effect on melting of the glaciers, thus, the comprehensive study of snow algae species would help to foresee and model interrelated processes of climate change in the ecosystem.

The red snow blooming in the Subpolar Urals was investigated. The ecological characteristics of habitats where blooming occurred, as well as, chemical parameters of the meltwater were studied. The snow contained important elements for algal development, including N, P, Ca, Mg and other biogenic compounds. The density of algal cells in samples reached 0.33 × 10⁴ cells per ml^-1. A Chloromonas reticulata strain isolated from the red snow with massive development of biflagellate algae was studied in detail. The algal strain is stored in a collection of living algae in Institute of Biology Komi Scientific Center (SYKOA Ch-054-11). Based on analysis of ITS2 sequences, morphological and ultrastructural characteristics, the studied biflagellate strain has been placed to Chloromonas clade, Reticulata group with a high bootstrap support. The set of ultrastructural characters detected in isolated strain matched with that of previously described for other Chloromonas reticulata strains. Minor morphological deviations that were observed in Chloromonas reticulata strain from SYKOA Ch-054-11 in comparison with the strains SAG 29.83, SAG 32.86 and SAG 26.90 could be attributed to a latitudinal gradient differences and ecological conditions.

An Euastrum species (Conjugatophyceae, Streptophyta) was found in an agricultural ditch fed by a rheocrenic, slightly-hot spring ‘Ain El-Balad’ in the El-Farafra Oasis, Western Desert of Egypt. Morphotaxonomic diagnosis and autecology of this desmid species are hereby documented in detail and compared to other morphologically similar species and infraspecific taxa, particularly those of the species complex E. spinulosum. As compared to most other species of that complex, the newly described Euastrum species is mainly characterized by its distinctive small-sized cells, rather shallow and widely open invaginations between the semicell lobes and less pronounced apical lobes. Moreover, the basal lobes are broadly rounded and larger than the lateral lobes. We have named this interesting species E. elfarafraense sp. nov. after the type locality, the El-Farafra Oasis.

Collection de cultures de microalgues d'eau douce de l'archipel des Açores : ressource pour la recherche taxonomique et la phycoprospection. Ces dernières années, un grand intérêt a été porté sur le potentiel biotechnologique des microalgues, notamment du fait de leur rapide croissance et de l'identification de certaines substances synthétisées par ces organismes. L'isolation puis la culture in vitro d'espèces de microalgues natives sont très importantes pour les études taxonomiques et les études de conservation. Elles représentent les premières étapes des études de faisabilité pour des productions commerciales locales. Dans cette étude, 114 microalgues ont été isolées à partir d'échantillons prélevés dans 23 stations de l'île de São Miguel, Açores. Parmi celles-ci, 60 espèces ont été identifiées dont 39 Chlorophytes, 10 Ochrophytes, 6 Cyanophytes, 3 Charophytes, 1 Euglénozoaire et 1 Cryptophyte. Dix-huit de ces identifications d'espèces constituent de nouveaux enregistrements pour l'île de São Miguel.

The diatom genus Entomoneis includes species with a unique morphology, having panduriform frustules in girdle view, often twisted about its apical axis, with some unique characters such as a sigmoid raphe on elevated bilobate keel, differently shaped junction lines, numerous girdle bands and variously perforated striae. Most of the species belonging to this genus are found to be brackish or marine, with some occurrences in freshwater habitats, but not one species has been described as exclusively freshwater. In this study, the new freshwater diatom species Entomoneis triundulata sp. nov. is described based on a detailed morphological observation using light and scanning electron microscopy. The specific features of E. triundulata are its triundulate valve margin; the shape of the transition between keel and valve body having a proximal U-shaped end, a slightly curved middle segment and a distal V-shaped end; and five sub-compartments to the frustule cavity. Besides morphological features unique to E. triundulata, similarities with other Entomoneis species are reported and discussed.

A new monotypic diatoms genus from Brazil is described based on gatherings and descriptions from the Amazon made by Hustedt in the early 50's. Burliganiella gen. nov. is described using light and scanning electron microscope and has as generitype Burliganiella siolii (Hustedt) comb. nov., originally described within Fragilaria Lyngb. The main diagnosed features include valves slightly asymmetrical to the apical axis with a sternum located near the ventral margin (Eunotia-like) while internally having slits that are not associated with a helictoglossa and no rimoportula (which is completely absent). While some characters link the species to the ‘araphid’ genus Fragilariforma D.M. Williams & Round, Burliganiella has more shared characters with the Eunotiales. For instance, the lack of a raphe in other species of eunotioid diatoms, suggests multiple lineages within the Eunotiales have reduced or lost raphe systems, such as in the case of Burliganiella.