798 research outputs found
Out of the Black Sea: Phylogeography of the Invasive Killer Shrimp Dikerogammarus villosus across Europe
The amphipod Dikerogammarus villosus has colonized most of the European main inland water bodies in less than 20 years, having deteriorating effect on the local benthic communities. Our aim was to reveal the species phylogeography in the native Black Sea area, to define the source populations for the colonization routes in continental Europe and for the newly established UK populations. We tested for the loss of genetic diversity between source and invasive populations as well as along invasion route. We tested also for isolation by distance. Thirty three native and invasive populations were genotyped for mtDNA (COI, 16S) and seven polymorphic nuclear microsatellites to assess cryptic diversity (presence of deeply divergent lineages), historical demography, level of diversity within lineage (e.g., number of alleles), and population structure. A wide range of methods was used, including minimum spanning network, molecular clock, Bayesian clustering and Mantel test. Our results identified that sea level and salinity changes during Pleistocene impacted the species phylogeography in the Black Sea native region with four differentiated populations inhabiting, respectively, the Dnieper, Dniester, Danube deltas and Durungol liman. The invasion of continental Europe is associated with two sources, i.e., the Danube and Dnieper deltas, which gave origin to two independent invasion routes (Western and Eastern) for which no loss of diversity and no isolation by distance were observed. The UK population has originated in the Western Route and, despite very recent colonization, no drastic loss of diversity was observed. The results show that the invasion of the killer shrimp is not associated with the costs of loosing genetic diversity, which may contribute to the success of this invader in the newly colonized areas. Additionally, while it has not yet occurred, it might be expected that future interbreeding between the genetically diversified populations from two independent invasion routes will potentially even enhance this success
Isolation and characterization of 8 microsatellite loci for the ââkiller shrimpââ, an invasive Ponto-Caspian amphipod Dikerogammarus villosus (Crustacea: Amphipoda)
Dikerogammarus villosus is a freshwater
amphipod of the Ponto-Caspian origin recognized as one of
the 100 worst alien species in Europe, having negative
impact on biodiversity and functioning of the invaded
aquatic ecosystems. The species has a wide ecophysiological
tolerance and during the last 20 years it has rapidly
spread throughout European inland waters. In consequence,
it presents a major conservation management problem. We
describe eight polymorphic microsatellite loci developed
for D. villosus by combining a biotin-enrichment protocol
and new generation 454GS-FLX Titanium pyrosequencing
technology. When genotyped in 64 individuals from two
locations, the loci exhibited a mean diversity of 4.87 alleles
per locus (2â13). The mean observed and expected heterozygosities
were, respectively, 0.439 (0.091â0.844) and
0.468 (0.089â0.843). Gametic disequilibrium was not
detected for any pair of loci. The microsatellite markers
will be a valuable tool in assessing the demographic processes
associated with invasion of the killer shrimp from a
genetic point of view
Parasites, pathogens and commensals in the âlow-impactâ non-native amphipod host Gammarus roeselii
Background: Whilst vastly understudied, pathogens of non-native species (NNS) are increasingly recognised as important threats to native wildlife. This study builds upon recent recommendations for improved screening for pathogens in NNS by focusing on populations of Gammarus roeselii in Chojna, north-western Poland. At this location, and in other parts of continental Europe, G. roeselii is considered a well-established and relatively âlow-impactâ invader, with little understanding about its underlying pathogen profile and even less on potential spill-over of these pathogens to native species. Results: Using a combination of histological, ultrastructural and phylogenetic approaches, we define a pathogen profile for non-native populations of G. roeselii in Poland. This profile comprised acanthocephalans (Polymorphus minutus Goese, 1782 and Pomphorhynchus sp.), digenean trematodes, commensal rotifers, commensal and parasitic ciliated protists, gregarines, microsporidia, a putative rickettsia-like organism, filamentous bacteria and two viral pathogens, the majority of which are previously unknown to science. To demonstrate potential for such pathogenic risks to be characterised from a taxonomic perspective, one of the pathogens, a novel microsporidian, is described based upon its pathology, developmental cycle and SSU rRNA gene phylogeny. The novel microsporidian Cucumispora roeselii n. sp. displayed closest morphological and phylogenetic similarity to two previously described taxa, Cucumispora dikerogammari (Ovcharenko & Kurandina, 1987), and Cucumispora ornata Bojko, Dunn, Stebbing, Ross, Kerr & Stentiford, 2015. Conclusions: In addition to our discovery extending the host range for the genus Cucumispora Ovcharenko, Bacela, Wilkinson, Ironside, Rigaud & Wattier, 2010 outside of the amphipod host genus Dikerogammarus Stebbing, we reveal significant potential for the co-transfer of (previously unknown) pathogens alongside this host when invading novel locations. This study highlights the importance of pre-invasion screening of low-impact NNS and, provides a means to document and potentially mitigate the additional risks posed by previously unknown pathogens
Can birds enhance the dispersal of freshwater macrocrustaceans?
The freshwater crustaceans, Crangonyx pseudogracilis, Atyaephyra desmaresti and Procambarus clarkii (hereby referred to as FCs) are non-native in several areas of their distribution range presumably due to human-mediated introductions. Here we test dispersal by waterbirds as a complementary mechanism of dispersal of these 3 species. For P. clarkii, we studied the transport of recently hatched juveniles while, for the other two species, adults were used. In an initial experiment, we evaluated the effect of environmental conditions and size on FCs desiccation survival time. Next, we performed a set of experiments to evaluate the likelihood of FCs taking a bird transport vector. This was quantified using a freshly dead mallard (Anas platyrhynchos) or mallardâs feet under still or moving conditions. A third set of experiments evaluated FCs survival probability during transport by birds. For that purpose we released, at several distances, pigeons carrying FCs on a small mesh bag. In addition, we also used a freshly dead mallard mounted on the top of a moving vehicle and carrying FCs on its feathers.
All 3 species were capable of clinging to mallardâs feathers and to mallardâs feet resulting in successful transport. A value of the probability of taking the transport vector was obtained for each species under each set of experimental conditions. This probability depends on the water depth, on the resting time of the vector and on the stillness or movement of the vector. The time lengths for 50% or 90% mortality (LT50 and LT90) of the FCs when removed from the water and also when transported by birds show that they are capable of surviving overland bird transport. We found that some P. clarkii juveniles survived distances up to 150 km outside a moving vehicle simulating bird flight and up to 62 km when transported by birds. Nevertheless, the majority of the FCs was only capable of surviving much smaller distances. Our results have shown that FCs ectozoochory is possible and that, distance, size and environmental conditions can significantly affect the likelihood of survival of FCs during bird flight
Mitochondrial Genomes, Phylogenetic Associations, and SNP Recovery for the Key Invasive Ponto-Caspian Amphipods in Europe
The Ponto-Caspian region is the main donor of invasive amphipods to freshwater ecosystems, with at least 13 species successfully established in European inland waters. Dikerogammarus spp. and Pontogammarus robustoides are among the most successful, due to their strong invasive impact on local biota. However, genomic knowledge about these invaders is scarce, while phylogeography and population genetics have been based on short fragments of mitochondrial markers or nuclear microsatellites. In this study, we provide: (i) a reconstruction of six mitogenomes for four invasive gammarids (D. villosus, D. haemobaphes, D. bispinosus, and P. robustoides); (ii) a comparison between the structure of the newly obtained mitogenomes and those from the literature; (iii) SNP calling rates for individual D. villosus and D. haemobaphes from different invasion sites across Europe; and (iv) the first time-calibrated full mitogenome phylogeny reconstruction of several Ponto-Caspian taxa. We found that, in comparison to other gammarids, the mitogenomes of Ponto-Caspian species show a translocation between the tRNA-E and tRNA-R positions. Phylogenetic reconstruction using the mitogenomes identified that Ponto-Caspian gammarids form a well-supported group that originated in the Miocene. Our study supports paraphyly in the family Gammaridae. These provided mitogenomes will serve as vital genetic resources for the development of new markers for PCR-based identification methods and demographic studies
Cenozoic origins of the genus Calliarcys (Insecta, Ephemeroptera) revealed by MicroâCT, with DNA barcode gap analysis of Leptophlebiinae and Habrophlebiinae
We are grateful to Michel Sartori (Lausanne, Switzerland) and JosĂ© Ăngel MartĂn del Arco (Salamanca, Spain)
for donating the specimens of C. humilis to SMNS, BC CAS, and UĆ collections. We are also grateful to Christel
and Hans-Werner Hoffeins (Hamburg, Germany), Mike Reich (BSPG, Munich, Germany), and Evgeny
Perkovsky (Schmalhausen Institute of Zoology, Kyiv, Ukraine) for access to their collections of fossil mayflies
from the Eocene Rovno amber. We would like to thank KateĆina BlĂĄhovĂĄ (IE, BC CAS) and Milan Pallmann
(SMNS) for technical assistance with line drawings and the preparation of a set of macro photographs.
Tomasz Mamos (UniLodz, Poland) is acknowledged for his help in the Bayesian reconstruction of phylogeny,
and Ćukasz TrÄbicki (UniLodz, Poland) for help in molecular laboratory. Comments from reviewers helped to
improve the manuscript. JA-T thank the staff of Bruker SkyScan in Kontich (Belgium) for their effectiveness
and fast support, for their constant improvements to the software, and for implementing the new options we
requested. In this respect, we are especially indebted to Alexander Sasov (now at NeoScan, https:// neosc an.
com), Stephan Boons, Xuan Liu, Phil Salmon, and Vladimir Kharitonov. We would like to thank the reviewers
for their thoughtful comments and efforts towards improving our manuscript. LSID urn:lsid:zoobank.
org:pub:C58BEE82-0EC6-4C59-A02D-1E5F796179B6Additional information
Supplementary Information The online version contains supplementary material available at https:// doi. org/
10. 1038/ s41598- 022- 18234-4.Funding
Open access funding enabled and organized by the University of ĆĂłdĆș (Poland). RJG acknowledges the financial
support of the Grant Agency of the Czech Republic (No. 21-05216S) and institutional support of the Institute of
Entomology (Biology Centre of the Czech Academy of Sciences) RVO: 60077344. Acquisition of research equipment
used in this study has been carried out within equipment subsidy granted by Alexander von Humboldt
Foundation [Georg Forster Research Fellowship for Experienced Researchers] for RJG.Mayflies (Ephemeroptera) are among the oldest pterygote insects, with the earliest fossils dating back to the Late Carboniferous. Within mayflies, Leptophlebiidae are a highly diverse and widespread group, with approximately 140 genera and 640 species. Whereas taxonomy, systematics, and phylogeny of extant Leptophlebiidae are in the focus of extensive studies, little is known about leptophlebiid fossil taxa. Because fossil remains of Ephemeroptera in sedimentary rocks are relatively rare, inclusions of mayflies in amber are a unique source of information on their evolution and diversity in the past. Leptophlebiidae found in Cenozoic resins mostly belong to the subfamilies Leptophlebiinae (in Eocene Baltic amber) and Atalophlebiinae (in Miocene Dominican and Mexican ambers). In the present contribution, we confirm the first finding of the genus Calliarcys from Eocene Baltic amber by using Micro-CT, which allowed confirming its generic placement by visualizing diagnostic key characters otherwise hidden by a cloud of turbidity. Additionally, we present first molecular data on the extant species Calliarcys humilis Eaton, 1881 from the Iberian Peninsula and the barcode gap analysis for Leptophlebiinae and Habrophlebiinae.Funding
Open access funding enabled and organized by the University of ĆĂłdĆș (Poland)Grant Agency of the Czech Republic (No. 21-05216S)Institute of
Entomology (Biology Centre of the Czech Academy of Sciences) RVO: 60077344Alexander von Humboldt
Foundation [Georg Forster Research Fellowship for Experienced Researchers
Zoogeography of epigean freshwater Amphipoda (Crustacea) in Romania: fragmented distributions and wide altitudinal variability
Inland epigean freshwater amphipods of Romania are diverse and abundant for this region has a favourable geographical position between the Balkans and the Black Sea. Excluding Ponto-Caspian species originating in brackish waters and freshwater subterranean taxa, there are 11 formally recognized epigean freshwater species recorded from this country. They belong to 3 genera, each representing a different family: Gammarus (Gammaridae, 8 species or species complexes), Niphargus (Niphargidae, 2 epigean species) and Synurella (Crangonyctidae, one species). Their large-scale distribution patterns nevertheless remain obscure due to insufficient data, consequently limiting biogeographical interpretations. We provide extensive new data with high resolution distribution maps, thus improving the knowledge of the ranges of these taxa. Gammarus species display substantial altitudinal variability and patchy, fragmented distribution patterns. They occur abundantly, particularly in springs and streams, from lowlands to sub-mountainous and mountainous regions. In the light of recent molecular research, we hypothesize that the complex geomorphological dynamics of the Carpathian region dur-ing the Late Tertiary probably contributed to their allopatric distribution pattern. Contrasting with Gammarus, the genera Niphargus and Synurella exhibit low altitudinal variability, broad ecological valences and overlapping distributions, being widespread throughout the lowlands. The current distribution of N. hrabei and N. valachicus seems to be linked to the extent of the Paratethys during the Early Pliocene or Pleistocene. We further discuss the taxonomic validity of two syn-onymized and one apparently undescribed taxon, and provide an updated pictorial identification key that includes all taxa and forms discussed in our study. The mosaic distribution of epigean freshwater amphipod species in Romania shows that this region is particularly suitable for phylo- and biogeographical analyses of this group.
Zoogeography of epigean freshwater Amphipoda (Crustacea) in Romania: fragmented distributions and wide altitudinal variability (PDF Download Available). Available from: https://www.researchgate.net/publication/269250979_Zoogeography_of_epigean_freshwater_Amphipoda_Crustacea_in_Romania_fragmented_distributions_and_wide_altitudinal_variability [accessed Apr 20, 2016].We kindly thank Marius G. Berchi, Miklos Balint and Bogdan Horia for providing material, and to all the students
that helped during the field work. An anonymous reviewer provided helpful comments on a previous version of the
manuscript. This work was financially supported by the University Research National Council Agency of Romania
(CNCS-UEFISCDI), exploratory research projects PCE-4 1458/2008 as well as by the Polish Ministry of Science
and Higher Education, project N N303 579439. DCC was also supported by the Charles University in Prague
(projects GAUK 1398214 and SVV 260088)
Differences in clinical characteristics and 1-year outcomes of hospitalized patients with heart failure in ESC-HF Pilot and ESC-HF-LT registries
[Abstract] INTRODUCTION The management of heart failure (HF) has changed significantly in recent decades.
OBJECTIVES We analyzed the clinical profile, 1âyear outcomes, predictors of mortality, and hospital readmissions in hospitalized patients enrolled in the European Society of Cardiology Heart Failure Pilot Survey (ESCâHF Pilot) and Heart Failure LongâTerm Registry (ESCâHFâLT).
PATIENTS AND METHODS The analysis included hospitalized Polish patients from both registries. The primary endpoint was allâcause death at 1 year, while the secondary endpoint was allâcause death or hospitalization for worsening HF at 1 year.
RESULTS The study included a total of 1415 hospitalized patients (650 from ESCâHF Pilot; 765 from ESCâHFâLT). The primary endpoint occurred in 89 of the 650 patients (13.7%) and in 120 of the 711 patients (16.9%) from ESCâHF Pilot and ESCâHFâLT, respectively (P = 0.11). The secondary endpoint was more frequent in ESCâHF Pilot than in ESCâHFâLT (201 of 509 [39.5%] vs 222 of 663 [33.5%]; P = 0.04). Compared with ESCâHF Pilot, patients from the ESCâHFâLT registry were older and more often had hypertension, atrial fibrillation, peripheral artery disease, and chronic kidney disease, while the incidence of chronic obstructive pulmonary disease was lower. The percentage of patients receiving drugs for HF (diuretics, angiotensinâconverting enzyme inhibitors, angiotensin receptor blockers, ÎČâblockers, mineralocorticoid receptor antagonists), anticoagulants, cardiac resynchronization therapy, and implantable cardioverterâdefibrillator were higher in the ESCâHFâLT group in comparison with the ESCâHF Pilot group.
CONCLUSIONS Patients from the ESCâHFâLT registry had a lower risk of death or hospitalization for worsening HF despite the fact that they were older and had more comorbidities. The results might suggest an improvement in physiciansâ adherence to the guidelines on the management of HF in the ESCâHFâLT registry
Impacts of invasive alien marine species on ecosystem services and biodiversity: a pan-European review
Abstract
prerequisite for the efficient prioritisation of actions to prevent new invasions or for developing mitigation measures. In this review, we identified alien marine species that have a high impact on ecosystem services and biodiversity in European seas, classified the mechanisms of impact, commented on the methods applied for assessing the impact and the related inferential strength, and reported on gaps in available information. Furthermore, we have proposed an updated inventory of 87 marine species in Europe, representing 13 phyla, which have a documented high impact on ecosystem services or biodiversity.
Food provision was the ecosystem service that was impacted by the greatest number of alien species (in terms of both positive and negative impacts). Following food provision, the ecosystem services that were negatively affected by the highest number of alien species were ocean nourishment, recreation and tourism, and lifecycle maintenance, while the ecosystem services that were most often positively impacted were cognitive benefits, water purification, and climate regulation. In many cases, marine aliens were found to impact keystone/protected species and habitats. Thirty percent of the assessed species had an impact on entire ecosystem processes or wider ecosystem functioning, more often in a negative fashion. Forty-nine of the assessed species were reported as being ecosystem engineers, which fundamentally modify, create, or define habitats by altering their physical or chemical properties.
The positive impacts of alien species are probably underestimated, as there is often a perception bias against alien species. Among the species herein assessed as high-impact species, 17 had only negative and 7 only positive impacts; for the majority (63 species), both negative and positive impacts were reported; the overall balance was often unknown. Although there is no doubt that invasive species have modified marine ecosystems, evidence for most of the reported impacts is weak, as it is based on expert judgement or dubious correlations, while only 13% of the reported impacts were inferred via manipulative or natural experiments. A need for stronger inference is evident, to improve our knowledge base of marine biological invasions and better inform environmental managers
Comparative analysis of long-term outcomes of torasemide and furosemide in heart failure patients in heart failure registries of the European Society of Cardiology
[Abstract] Purpose. Current clinical recommendations do not emphasise superiority of any of diuretics, but available reports are very encouraging and suggest beneficial effects of torasemide. This study aimed to compare the effect of torasemide and furosemide on long-term outcomes and New York Heart Association (NYHA) class change in patients with chronic heart failure (HF).
Methods. Of 2019 patients enrolled in Polish parts of the heart failure registries of the European Society of Cardiology (Pilot and Long-Term), 1440 patients treated with a loop diuretic were included in the analysis. The main analysis was performed on matched cohorts of HF patients treated with furosemide and torasemide using propensity score matching.
Results. Torasemide was associated with a similar primary endpoint (all-cause death; 9.8% vs. 14.1%; pâ=â0.13) occurrence and 23.8% risk reduction of the secondary endpoint (a composite of all-cause death or hospitalisation for worsening HF; 26.4% vs. 34.7%; pâ=â0.04). Treatment with both torasemide and furosemide was associated with the significantly most frequent occurrence of the primary (23.8%) and secondary (59.2%) endpoints. In the matched cohort after 12 months, NYHA class was higher in the furosemide group (pâ=â0.04), while furosemide use was associated with a higher risk (20.0% vs. 12.9%; pâ=â0.03) of worsening â„â1 NYHA class. Torasemide use impacted positively upon the primary endpoint occurrence, especially in younger patients (aged <â65 years) and with dilated cardiomyopathy.
Conclusions. Our findings contribute to the body of research on the optimal diuretic choice. Torasemide may have advantageous influence on NYHA class and long-term outcomes of HF patients, especially younger patients or those with dilated cardiomyopathy, but it needs further investigations in prospective randomised trials
- âŠ