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Resilience of beach morphometric characteristics on decadal time scale: a case study from the Lithuanian Baltic Sea /
No full textResponse of freshwater periphytic diatoms to elevated cadmium concentration: results of an experimental study /
No full textThe study emphasises the importance of periphytic freshwater diatoms as bioindicators for assessing the impact of cadmium pollution on aquatic ecosystems. This approach offers significant advantages for the detection of ecological changes, such as shifts in diatom species diversity and community composition, as well as morphological changes, thus contributing to a deeper understanding of metal-related environmental risks. The aim of the study was to determine the effects of cadmium on the diversity and structure of periphytic diatom communities under laboratory conditions, and to evaluate the use of diatoms as bioindicators for cadmium exposure. During the entire experiment, in which four cadmium concentrations were tested (0 mg L–1, 0.01 mg L–1, 0.04 mg L–1 and 0.1 mg L–1), a total of 85 diatom taxa were found, with the greatest diversity in the control. However, no significant effect was found on diatom taxa richness, abundance and Shannon-Wiener diversity index. A multivariate analysis (NMDS, PERMANOVA) also showed no clear differences in the structure of the periphytic diatom community under cadmium exposure. However, the cadmium concentration in the treatments was reliably indicated by Navicula lanceolata, Navicula gregaria and Navicula rostellata, whose cell proportion decreased significantly with increasing cadmium content, and by Achnanthidium sp., and Fragilaria sp., whose proportion in the samples increased with increasing cadmium content. The frequency of deformation of frustules increased with higher cadmium concentrations and varied between 8.15% at 0.01 mg Cd L–1 and 12.36% at 0.1 mg Cd L–1. It was found that N. rostellata is the most susceptible to frustule deformation and could therefore represent the most valuable bioindicator among the periphytic diatoms analysed
Lake minnow, Rhynchocypris percnurus (Actinopterygii, Cypriniformes, Leuciscidae), in Lithuanian inland waters: Distribution and current population state /
No full textThe endangered lake minnow, Rhynchocypris percnurus (Pallas, 1814), has been known from Lithuanian inland waters for over 20 years, but we have a very limited understanding of its current population size. The main purpose of this study was to provide a concise account of the species in Lithuania, including a rough assessment of threats to its populations and habitats. In 2018-2019, we investigated 360 small water bodies across the country, all of which were potentially suitable for lake minnows. Results revealed that lake minnows were present in only 12 water bodies, all concentrated in one regional park in the southern part of the country. However, by 2024 the species had gone extinct at nine of these sites due to habitat loss. At present (2025), only one viable Lithuanian population of this species can be considered to exist. Our results conclusively show that the species is on the very edge of extinction. Urgent action is needed to protect this species in Lithuanian waters, with special emphasis on revitalizing its most suitable habitats and translocating fish from the only currently known population in Lithuania
From clay to pottery: microanalytical insights into raw materials, paste recipes, and ceramic traditions in Neolithic west Lithuania /
No full textThis study analyzes clay sources, ceramic paste recipes, and technological choices in Neolithic pottery from west Lithuania, where local hunter–fisher–gatherer groups encountered incoming communities of the Globular Amphora (GAC) and Corded Ware cultures (CWC) during the fourth to third millennium BCE. Thirty sherds from coastal Šventoji and the inland Biržulis region were analyzed by optical microscopy and SEM–EDS, revealing that most ceramic pastes comprise variegated hydromicaceous clay with quartz and feldspar. In Narva Culture pottery, vessels from the Biržulis region (Daktariškė 5) are dominated by fine-grained clay, whereas Šventoji examples are more variegated and diatom-bearing; both assemblages show organic inclusions (mussel shell, bone, charred plant material) and very low firing temperatures (<650 °C). GAC exhibits cross-site coherence, characterized by crushed, deformed, cataclastic muscovite granite in fine lacustrine clay and low firing temperatures (~650–750 °C). CWC from Daktariškė 5 geochemically clusters with Narva and hybrid-type pottery, while CWC at Šventoji aligns with GAC; both show low firing temperatures (~650–750 °C). Ceramic pastes contain argillaceous clasts partly diffused or intertwined with the main matrix; only a few show traits typical of grog. All pottery was made from local Quaternary glacial sediments, with cultural traditions and environmental context shaping clay selection and manipulation
Phragmataecia druska – a new species from the Ararat valley in Armenia (Lepidoptera, Cossidae) /
No full textNew species of the genus Phragmataecia Newman, 1850; Phragmataecia druska sp. n.; is described from western and central Armenia. It is compared with other species: Ph. castaneae (Hübner, 1790); Ph. albida Erschoff, 1874; Ph. furia (Grum-Grshimailo, 1890); Ph. roborowskii Alphéraky, 1897; Ph. pacifica Yakovlev, 2007; Ph. turkmenbashi Yakovlev, 2008; Ph. anikini Yakovlev, 2011; Ph. valikhanovi Yakovlev & Witt, 2016; and Ph. effendii Yakovlev & Snegovaya, 2020. Adult males, photos and drawings of their genitalia, map with approximate distribution area of Ph. castaneae and Ph. albida and collection localities of other species, and photos of the habitat for the new species are illustrated
New crane fly species of the subgenus Tipula (Vestiplex) Bezzi (Diptera, Tipulidae) from Qinghai-Tibet Plateau, China /
No full textFour new crane fly species of the subgenus Tipula (Vestiplex) Bezzi, 1924, T. (V.) apteroides sp. nov. (Yunnan), T. (V.) bidentata sp. nov. (Sichuan), T. (V.) spinaventralis sp. nov. (Sichuan) and T. (V.) ventrobasilata sp. nov. (Sichuan) are described and illustrated, providing discussion on separation of the newly described species from other closely related species. The male genitalia of T. (V.) aestiva Savchenko, 1960 is illustrated and redescribed
Light and temperature effects on the accumulation of carotenoids in Rhodotorula spp. yeasts /
No full textCarotenoids are widely recognized for their antioxidant and health-beneficial properties, making them attractive for applications in the food, pharmaceutical, medical, and agricultural sectors. Rhodotorula yeasts are considered one of the most suitable alternatives for carotenoid synthesis due to their rapid biomass growth and high pigment yield. During this study, based on the sequences of the ITS region between 18S and 28S rRNA genes, the yeast strains were identified as belonging to Rhodotorula babjevae, R. dairenensis, R. diobovata, R. glutinis, R. graminis, R. ingeniosa, R. kratochvilovae, and R. mucilaginosa. The production of carotenoids by different Rhodotorula yeast strains was analyzed under the combined effects of lighting and temperature. Among all tested strains, the isolate identified as R. ingeniosa exhibited the lowest carotenoid content, ranging from 0.18 to 0.23 mg/g biomass. The highest levels of pigment were accumulated in dark conditions by R. babjevae (0.86 mg/g biomass) and R. graminis (0.76 mg/g biomass) cultivated for 14 days at a constant temperature of 26 °C, and by R. glutinis (0.89 mg/g biomass) after incubation at 4 °C. The majority of yeasts tested produced more carotenoids at a higher temperature. It was observed that in R. babjevae, R. glutinis, and R. graminis, lighting negatively affected the pigment content regardless of incubation temperature. In these strains, the pigment content decreased by 1.2- to 1.4-fold after one week of cultivation under light conditions at 26 °C, compared to cultures grown in the dark. The results suggest that the isolated Rhodotorula strains could be attractive candidates for the efficient synthesis of carotenoids
Dressed for the weather: Tawny owl feather adaptations across a climatic gradient /
No full textPopulations are presumed to be adapted to local environmental conditions via natural selection, with gene flow breaking up local adaptations. In birds, various aspects of feathers may reflect local adaptation. For example, the insulation capacity of feathers could be greater in colder regions, while colour variation may also play a role in adapting to local environmental conditions since darker feathers are known to absorb more heat than lighter ones. We studied feather properties (plumulaceous part of the feather, density of barbs and barbules) of tawny owl, Strix aluco, across nine populations covering a large part of the species' European range (9–52 individuals per population) as well as their plumage colour, scored as dark (brown) versus light (grey) morphs. We compared these traits' phenotypic divergence (PST) with the divergence expected based on genetic drift (FST) inferred using eight microsatellites. The FST was low (0.022; 95% CI 0.005–0.039), and most feather structures' phenotypic divergence (PST) exceeded the FST. However, phenotypic divergence in plumage colour was low and not significant, implying a limited role of natural selection in shaping variation in plumage colouration at large spatial scales. Between-population differentiation in feather properties was more pronounced in ventral feathers than dorsal feathers. In colder populations, the plumulaceous part of the dorsal feathers, but not the ventral feathers, was larger (implying greater insulation). Although proper evaluation hinges on understanding how insulative properties confer a fitness advantage in a given environment, our findings imply that properties of avian feathers may reflect local adaptation, possibly related to climate
Integrative study of the crane fly genus Brithura Edwards, 1916 (Diptera: Tipulidae) in East Asia: first larval descriptions of the genus and insights from adult morphology and DNA barcoding /
No full textBrithura Edwards, 1916 (Diptera: Tipulidae) is a small genus of crane flies currently comprising 16 described species distributed across the East Palaearctic and Oriental regions. Although the adults of this genus rank among the largest representatives of the family Tipulidae, their immature stages have remained undocumented until now. In this study, mitochondrial cytochrome c oxidase subunit I (COI) gene fragment sequences (DNA barcodes) of Brithura sancta Alexander, 1929 were analyzed using both recently collected adult specimens from the Republic of Korea and historical museum specimens from China (collected in 1933). These sequences were compared with COI data obtained from larvae collected in Republic of Korea. We present the first description, with detailed illustrations and ecological information, of the previously unknown final instar larva of Brithura, specifically for the East Palaearctic species B. sancta. Diagnostic larval characters for the genus are discussed. Additionally, a redescription and comprehensive morphological documentation of the adult male and female B. sancta, including habitus and genitalia, are provided. This study represents the first phylogenetic contribution to the taxonomy of Brithura larvae based on mitochondrial COI sequence data
Tissue stages of Haemoproteus parasites (Haemosporida, Apicomplexa) in Ficedula flycatchers with evidence for phenotypic variation in Haemoproteus balmorali and implications for haemosporidian taxonomy /
No full textDuring exo-erythrocytic merogony, avian Haemoproteus parasites (Apicomplexa, Haemosporida) develop distinct tissue stages: small meronts and large megalomeronts. Recent molecular studies suggest that Haemoproteus species develop either of the two morphotypes in naturally infected birds but earlier research indicates that certain species form both depending on the replicating cycle. Because data on tissue stages are limited to a few described species, patterns and mechanisms of (megalo-)merogony are unclear but required to better understand pathologies during haemoproteosis. In this study, we aimed to characterize exo-erythrocytic stages of Haemoproteus species in naturally infected flycatchers (Muscicapidae). Tissue samples of eight Ficedula hypoleuca and two Ficedula parva positive by PCR and blood smear microscopy were subjected to histology and in situ hybridization applying Haemoproteus lineage-specific probes. Additionally, laser capture microdissection was performed to enable molecular identification of individual tissue stages. A phylogenetic analysis based on the parasites’ cytochrome b gene (886 bp) was performed to explore the relationship of meront- and megalomeront-forming species within the genus Haemoproteus. In F. hypoleuca, we found meronts and megalomeronts, and molecular data indicate that both belong to Haemoproteus balmorali, suggesting phenotypic variation of this parasite. Phylogenetically, H. balmorali was closely related to Haemoproteus attenuatus, which develops similar meronts but no megalomeronts, suggesting varying phenotypic variation among closely related species. In F. parva, we detected megalomeronts and gametocytes of Haemoproteus majoris hPHSIB1, presenting the first record in that host. By contrast, in F. hypoleuca showing high H. pallidus gametocytaemia, no exo-erythrocytic stages were found, implying that merogony was completed and not coinciding with gametocytaemia. These results demonstrate that exo-erythrocytic development varies considerably between species and patterns of tissue merogony may not be generalized at genus level. Furthermore, we report significant nuclear hypertrophy of the host cell in Haemoproteus megalomeronts, a feature formerly considered unique to Leucocytozoon, challenging it's use for genus identification