The aim of this atlas is to present summarised information and to illustrate comprehensively the shell morphology and structure of the majority of recorded Sphagnum-dwelling testate amoebae in ...Bulgaria (a total of 120 species, each of them illustrated with 9 LM and SEM photos). Since most of these species appear to be widely distributed in Europe, as well as in many other regions of the world, the atlas may be of interest to all researchers on testate amoebae and can also be used by specialists in ecology, hydrobiology, palaeoecology and environmental monitoring.
The ultra-structure of the shell and the morphometric variability of soil inhabiting testate amoeba Lamtopyxis callistoma from Madagascar were studied by using light- and scanning electron ...microscopy. The biometrical characteristic of the species was made on the basis of 75 specimens measured. In addition to the diameter of the shell, six other shell characters were described biometrically for the first time. The analysis of the variation coefficients shows that the studied population of L. callistoma is comparatively homogeneous and almost all measured characters are weakly to moderate variable (CV less than 10%). Scanning electron microscopy (SEM) studies on the shell ultra-morphology show that it has a smooth apertural surface with a thick layer of porous and fibrous organic cement and a rough dorsal surface composed of bigger and angular pieces of quartz. The shell wall has a thickness of about 5-6 µm and is composed of three layers. Unlike the previously accepted opinion that species is characterized by the presence of four teeth, this study shows that population of L. callistoma from Madagascar is comprised of both, specimens with four teeth and specimens with three teeth, in ratio of about 60% to 40%. Taking into account the restricted geographical distribution, large sizes and characteristic apertural morphology of L. callistoma it is assumed that this species, like some bryophilic ‘Nebelas’ with circumaustral distribution (e.g. Apodera vas , Alocodera cockayni , Certesella certesi , Certesella martiali , etc.), can be used as an example that in free-living microbial eukaryotes ‘not everything is everywhere’.
Call to restrict neonicotinoids Goulson, Dave
Science (American Association for the Advancement of Science),
06/2018, Letnik:
360, Številka:
6392
Journal Article
The aim of this study was to assess the status of aquatic invasive alien species (IAS) in the shoreline zone of the Bulgarian sector of the Danube River, Danube tributaries, and adjacent standing ...water bodies in the frame of the Joint Danube Survey 4 (JDS4). Seven benthic macroinvertebrates and seven fish IAS were identified. The crayfish Faxonius limosus was frequently found and abundant in the tributaries. The mussels Corbicula fluminea, Dreissena rostriformis bugensis, and Sinanodonta woodiana dominated in the Danube River and the middle and lower reaches of the tributaries, while the fish Carassius gibelio, Perccottus glenii, and Lepomis gibbosus were most abundant in the standing water bodies. The integrated biocontamination estimated by taxonomic groups (crayfish, molluscs, and fish), sampling methods, and type of water bodies ranged from moderate in the shoreline zone of the Danube River, through moderate to high in the canals and lakes, to severe in the Danube tributaries and the reservoirs. The results demonstrate the importance of IAS in the assessment of the ecological status/potential of the water bodies in the DRB. The comprehensive evaluation of the aquatic IAS pressure will provide valuable information and support for the implementation of the national and EU IAS and water policies in the DRB.
Upland rivers across Europe still exhibit undisturbed conditions and represent a treasure that we cannot afford to lose. We hypothesize that the combination of pristine and modified conditions could ...demonstrate biological responses along the stressor gradients. Thus, the response of aquatic macrophyte communities to anthropogenic stressors along upland rivers in Bulgaria was studied. Six stressors were selected out of 36 parameters grouped into hydromorphological, chemical variables and combined drivers (catchment land use). The stressors strongly affected species richness on the basis of biological type (bryophytes vs. vascular plants) and ecomorphological type (hydrophytes vs. helophytes). Hydrological alteration expressed by the change of the river's base flow and altered riparian habitats has led to a suppression of bryophytes and a dominance of riverbank plant communities. Seventy-five percent of mountain sites were lacking bryophytes, and the vegetation at semi-mountainous sites was dominated by vascular plants. It can be concluded that hydropeaking, organic and inorganic pollution, and discontinuous urban structures caused important modifications in the aquatic macrophyte assemblages. Macrophyte abundance and the biological and ecomorphological type of aquatic macrophytes reflect multi-stressor effects in upland rivers.
Until now, a complete checklist of
-dwelling testate amoebae in Bulgaria has never been published. Records for species diversity and distribution in the country were scattered in many faunistic and ...ecological publications. The aim of the present study is to summarise all data for the species distribution at the level of country by reviewing the existing literature and by additional data obtained in our research over the past two years.
The checklist comprises 171 species, classified into 43 genera, 20 families, three orders, three classes and three phyla. We present data for 16 new
-dwelling testate amoebae in Bulgaria and new distribution data for 134 species. Of them, 99 species are recorded from Stara Planina Mt., for which there was no available data to date. Additionally are recorded 69 new species for Pirin Mt., 21 for Vitosha Mt. and 18 for Rila Mt. Thirty six species are synonymised according to the latest taxonomic changes. Two misidentified taxa (
Penard, 1902 and Difflugia compressa var. africana Gauthier-Lièvre et Thomas, 1958) are transferred into valid species
and
, respectively. Three of the recorded species have not been included in the checklist, because they are currently not refering to testate amoebae (
(Auerbach 1856) and
Korotneef, 1879 are gymnamoebae (naked amoebae) and
(Penard 1904) =
(Penard 1904) is freshwater foraminifera).
The present pilot study tested and validated the use of the ‘Invasive Alien Species in Europe’ smartphone app (IASapp) in the Lower Danube Region. The study was conducted in three stages: (1) Testing ...the effectiveness of the app in Bulgaria, Romania and Serbia by organizing information and field testing campaigns; (2) Improving and extending the functionality of the app and developing a list of the invasive alien species (IAS) of concern to the Danube River Basin (DRB); and (3) Testing the updated app during the Joint Danube Survey 4 campaign. Overall, 13 campaigns were carried out, during which seven aquatic IAS of EU concern and nine IAS relevant to the DRB were recorded. Currently, the developed new functionality of IASapp allows the recording of 64 IAS of DRB concern. The updated IASapp has an important role in increasing public awareness on IAS issues, as well as in enlarging the participation and output of citizen science in the IAS early detection, monitoring and reporting in the DRB. Therefore, the constant communication with existing stakeholder groups and establishment of new citizen science groups is crucial for increasing the effectiveness of using the IASapp in the Danube Region and tackling the IAS issues.
A new sphagnicolous species of the genus Nebela isolated from wet Sphagnum mosses gathered at Vitosha Mountain (Bulgaria) is described. Shell ultrastracture and morphological variability of Nebela ...golemanskyi sp. nov. are investigated using scanning electron microscopy. The newly described species is characterized by its almost uncompressed shell and by its large, rounded, voluminous and hollow structural elements (idiosomes). The analysis of the variation coefficients shows that the studied population is too homogeneous and all measured morphological characters are feebly variable (CV range from 3.28% to 5.02%). Size frequency distribution analysis indicates that N. golemanskyi is size-polymorphic species, characterized by not well-expressed main-size class in favour of many subsidiary classes. A biometrical and morphological comparison between N. golemanskyi and N. speciosa is made.
The mitochondrial Cytochrome Oxidase Subunit 1 gene (COI) has been promoted as an ideal “DNA barcode” for animal species and other groups of eukaryotes. However, the utility of the COI marker for ...species level discrimination and for phylogenetic analyses has yet to be tested within the Rhizaria. Accordingly, we analysed mitochondrial COI gene sequences and nuclear small subunit rDNA (SSU) sequences from several morphospecies of euglyphid testate amoebae (Cercozoa, Rhizaria) in order to evaluate the utility of these DNA markers for species discrimination and phylogenetic reconstructions. Sequences were obtained from eleven populations belonging to six
Cyphoderia
morphospecies that were isolated from field samples in North America and Europe. Mean inter-population COI sequence dissimilarities were on average 2.9 times greater than in the SSU, while the intra-population sequence dissimilarities were higher in the SSU (0-0.95%) than in the COI (0%); this suggests that the COI fragment is valuable for discriminating Cyphoderiidae isolates. Our study also demonstrated that COI sequences are useful for inferring phylogenetic relationships among Cyphoderiidae isolates. COI and SSU tree topologies were very similar even though the COI fragment used in these analyses (500
bp) was much shorter than the SSU sequences (1600
bp). Altogether, these results demonstrate the utility of the COI as a potential taxonomic DNA barcode for assessing cyphoderiid species diversity and for inferring phylogenetic relationships within the group.
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