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Morphological and molecular description of Sarcocystis myodes n. sp. from the Bank Vole (Clethrionomys glareolus) in Lithuania /
No full textNumerous rodent species have been broadly examined for Sarcocystis parasites. Never-theless, recent investigations on Sarcocystis spp. in voles are lacking. As many as 45 bank voles (Clethrionomys glareolus) captured in several locations in Lithuania were examined in the present study. Based on morphological, genetic, and phylogenetic results, sarcocysts detected in one bank vole were described as Sarcocystis myodes n. sp. Using light microscopy analysis, the observed sarcocysts were ribbon-shaped, 6000–3000 × 70–220 µm in size. Sarcocysts were characterized by a relatively thin (about 1 µm) and apparently smooth cyst wall. The lancet-shaped bradyzoites were 9.6–12.0 × 3.1–4.6 µm in size. By transmission electron microscopy, the sarcocyst wall was up to 1 µm thick, parasitophorous vacuolar membrane had small knob-like blebs. Based on 18S rDNA, 28S rDNA, cox1, rpoB, and ITS1 loci, S. myodes showed highest similarity with S. ratti from the black rat (Rattus rattus). According to phylogenetic placement, S. myodes was most closely related to Sarcocystis spp. that employ predatory mammals as their definitive hosts. Morphologically, sarcocysts of S. myodes have similar features to those of S. cernae, S. dirumpens, and S. montanaensis described in voles, however, they use birds of prey or snakes as their definitive hosts
Effects of low frequency electromagnetic radiation on Lemna minor growth parameters and generation of point mutations at GPx, CAT and APx genes /
No full textDevelopment of new technologies distributing electric power from power stations to our homes through a network of cables and wires, including numerous electric devices at working places and home environment become a source of electromagnetic radiation (EMR) much stronger than EMR of natural origin. To provide a better understanding of the impact of the EMR of anthropogenic origin on living organisms, we investigated the long-term effects of EMR on Lemna minor. In this study, plants of the L. minor laboratory clone were exposed to low frequency (50 Hz) electromagnetic radiation (LF EMR) growing clones in Petri dishes placed on the coils initially generating magnetic flux (MF) of 1 µT for first three weeks, 2 µT until 12th week and after 12th week of the experiment MF was enhanced up to 300 µT. We examined the response of the plants by sequencing DNA fragments that included promoter, intron, and exon regions of ascorbate peroxidase (APx), glutathione peroxidase (GPx), and catalase (Cat) genes) as well measured growth parameters growth intensity, frond area, and number of fronds. Comparison of growth parameters of L. minor clones exposed to 2 µT and 300 µT magnetic flux revealed positive effect stimulating growth of experimentally affected plants at 2 µT After the first 14 weeks of treatment, the growth parameters were lower in the directly exposed by LF EMR group than in the group grown distantly from the source of EMR. However, after 18 weeks from the beginning of the experiment no significant difference was observed between two groups of L. minor including directly and indirectly affected by LF EMR plants. Moreover, the signals of the impact of LF EMR on the plants as rising of new point mutations were detected. The significantly enhanced number of variations in DNA sequences of L. minor clones directly affected by LF EMR in comparison to indirectly affected clones were revealed at the introns of APx (P = 0.011), GPx (P = 0.009), and Cat (P = 0.044) genes starting from the 10th week of the experiment In conclusion, the comparison of DNA sequencing data together with measurements of growth parameters revealed differences in response at molecular and physiological levels of directly and indirectly affected L. minor clones providing evidence that response to the impact of LF EMR depended on the prolongation of the impact and the magnetic flux density
Exo-erythrocytic development of avian haemosporidian parasites in European owls /
No full textAvian haemosporidian parasites (Haemosporida, Apicomplexa) are globally distributed and infect birds of many orders. These pathogens have been much investigated in domestic and wild passeriform birds, in which they are relatively easy to access. In birds belonging to other orders, including owls (order Strigiformes), these parasites have been studied fragmentarily. Particularly little is known about the exo-erythrocytic development of avian haemosporidians. The goal of this study was to gain new knowledge about the parasites infecting owls in Europe and investigate their exo-erythrocytic stages. Tissue samples of 121 deceased owls were collected in Austria and Lithuania, and examined using polymerase chain reactions (PCR), histology, and chromogenic in situ hybridization (CISH). PCR-based diagnostics showed a total prevalence of 73.6%, revealing two previously unreported Haemoproteus and five novel Leucocytozoon lineages. By CISH and histology, meronts of several Leucocytozoon lineages (lASOT06, lSTAL5, lSTAL7) were discovered in the brains, heart muscles, and kidneys of infected birds. Further, megalomeronts of Haemoproteus syrnii (lineage hSTAL2) were discovered. This study contributes new knowledge to a better understanding of the biodiversity of avian haemosporidian parasites infecting owls in Europe, provides information on tissue stages of the parasites, and calls for further research of these under-investigated pathogens relevant to bird health
Dishkeya, a recently described endemic Tischeriidae genus, now discovered in Colombia /
No full textThis paper describes Dishkeya ursipedella Diškus, Mey & Stonis, sp. nov. from Cundinamarca, Choachi (Colombia). The new species was collected at night time at light, therefore, the host plant remains unknown. The examination of morphology of the male genitalia of D. ursipedella revealed a highly distinctive new taxon of trumpet moths belonging to the recently described endemic genus Dishkeya Stonis. The new species is illustrated with photographs of the male genitalia, adults, and habitats. In a pictorial scheme, the male genitalia characters of D. ursipedella are compared with those of all other currently known members of Dishkeya
Habitat preferences of Hamatocaulis vernicosus at the junction of continental and boreal phytogeographical regions (Lithuania) /
No full textBased on the Nature Conservation Act, the rare fen moss Hamatocaulis vernicosus (Bern Convention, EU habitat directive) is protected in more than 500 Natura 2000 territories of Europe. Knowledge on its ecology is required to ensure favourable conservation status, meanwhile data from specific regions is still insufficient. The aim of this study was to high-light habitat characteristics specific at the junction of boreal and continental biogeographical regions. The data of 63 study plots included cover and abundance of the plant species, water parameters (conductivity, pH, and concentrations of Ca2+, Fe3+, K+, Mg2+, NH4+, NO3-, and PO43-), topography type and microrelief form. The specific features both in terms of water parameters and vegetation were ascertained. The habitats showed wide variation and high amounts of electrical conductivity, calcium, iron and magnesium. Most associated species were Carex diandra, C. rostrata, Menyanthes trifoliata, and Calliergonella cuspidata. The highest restriction with the most frequent plant communities showed Marchantia polymorpha, Plagiomnium ellipticum, and Rumex acetosa. Thus, the study confirms the general trends known for the habitat preferences of H. vernicosus and highlights the regionally based characteristics related to both water physical-chemical parameters and vegetation. To ensure favourable status of H. vernicosus throughout Europe, conservation measures that consider the particular features of the regional habitats should be applied
Soil seed bank of alien and native Cornus (Cornaceae) taxa in Lithuania: What determines seed density and vertical distribution in soil? /
No full textSoil seed banks of alien plant species are sources of propagules that play a crucial role in plant population dynamics. Studies on seed banks of woody alien species are crucial for understanding mechanisms of their encroachment on natural habitats. This study aimed to compare vertical distribution, density and composition of seed banks formed by native Cornus sanguinea subsp. sanguinea and alien C. alba, C. sericea and C. sanguinea subsp. australis in the Southern Hemiboreal zone of Europe. Five sites for each of four taxa were selected for the study, and seeds were sampled using the soil core method (400 samples in two soil layers: the upper, 0–5 cm, and the lower, 5–10 cm). Extracted seeds were tested with tetrazolium chloride stain to assess their viability. Differences in the seed banks among taxa were compared using generalised linear mixed models (GLMM). The GLMM analysis revealed significant differences in soil seed bank densities in the upper soil between the studied taxa (p < 0.001). We found that two of the alien taxa (C. alba and C. sanguinea subsp. australis) formed a much denser seed bank containing more viable seeds than the native Cornus sanguinea subsp. sanguinea. All three alien species contained more viable seeds (from 40.7% to 45.2% in the upper soil layer) than the native C. sanguinea subsp. sanguinea (19.4% in the upper and 18.2% in the lower soil layer). The cover of Cornus and habitat type had no significant effect on the density of the seed bank, according to GLMM. This study supports the hypothesis that seed banks of alien C. alba and C. sanguinea subsp. australis are denser than those of native C. sanguinea subsp. sanguinea. Fur-thermore, the seed bank of alien taxa contained more viable seeds than the seed bank of C. sanguinea subsp. sanguinea. Results of this study contribute to the understanding of the invasiveness of alien Cornus taxa
Elimination of LRVs elicits different responses in Leishmania spp /
No full textLeishmaniaviruses (LRVs) have been demonstrated to enhance progression of leishmaniasis, a vector-transmitted disease with a wide range of clinical manifestations that is caused by flagellates of the genus Leishmania . Here, we used two previously proposed strategies of the LRV ablation to shed light on the relationships of two Leishmania spp. with their respective viral species ( L. guyanensis , LRV1 and L. major , LRV2) and demonstrated considerable difference between two studied systems. LRV1 could be easily eliminated by the expression of exogenous capsids regardless of their origin (the same or distantly related LRV1 strains, or even LRV2), while LRV2 was only partially depleted in the case of the native capsid overexpression. The striking differences were also observed in the effects of complete viral elimination with 2'C-methyladenosine (2-CMA) on the transcriptional profiles of these two Leishmania spp. While virtually no differentially expressed genes were detected after the LRV1 removal from L. guyanensis , the response of L. major after ablation of LRV2 involved 87 genes, the analysis of which suggested a considerable stress experienced even after several passages following the treatment. This effect on L. major was also reflected in a significant decrease of the proliferation rate, not documented in L. guyanensis and naturally virus-free strain of L. major . Our findings suggest that integration of L. major with LRV2 is deeper compared with that of L. guyanensis with LRV1. We presume this determines different effects of the viral presence on the Leishmania spp. infections
A new species of the genus Cottus (Scorpaeniformes, Cottidae) from the Baltic Sea Basin and its phylogenetic placement /
No full textThe genus Cottus contains more than 60 species that are common in freshwater bodies of northern Eurasia and North America. Despite the abundance of species, this genus has been insufficiently studied in Eastern European rivers and lakes. The new taxon Cottus cyclophthalmus sp. nov. was found in the Neman/Nemunas and Venta river systems (Baltic Sea Basin). Cottus cyclophthalmus is sister and most morphologically similar to Cottus gobio . The new species has the following diagnostic characters: round, protruding (tubular) eyes near front of head; dermal papillae on top and sides of head, naked body, absence of bony prickles, full trunk canal with 32–36 pores. The description of Cottus cyclophthalmus and a new finding of Cottus microstomus improved understanding of the Eastern European biodiversity