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Invasive alien species present a global threat to biodiversity, particularly where pathogens and symbionts are involved. Nonnative crayfish species can increase their impact on the host ecosystem through introductions of symbiotic fauna. Conversely, nonnative crayfishes could serve as hosts for native epibionts, thus substituting for disappearing native crayfishes as well. Here we report the presence of native branchiobdellids on naturalized populations of non-native crayfish Orconectes limosus and Pacifastacus leniusculus living in sympatry with native Astacus astacus. The native crayfish species probably served as a source of Branchiobdella spp. for non-native crayfishes. Two species of Branchiobdella (B. parasita and B. pentadonta) were found on P. leniusculus while only B. parasita was found on O. limosus. The level of colonization of inspected specimens and species was also evaluated. The mean number of branchiobdellids found on P. leniusculus and O. limosus was 26.0±15.9, and 64.8±27.7, respectively. Orconectes limosus was more heavily colonized by Branchiobdella despite being significantly smaller than P. leniusculus. Non-native species were corroborated as suitable to host the native epibionts. [ABSTRACT FROM AUTHOR]

The pet trade has been responsible for many introductions of non-native species. Freshwater ornamental plants and animals originating from the pet trade are stocked to garden ponds. The present survey focused on awareness and responsible behaviour related to biological invasion risks of companies that designed, built, and stocked garden ponds., A representative number ( n = 124) of companies (commercial garden pond architects and builders) in the Czech Republic were surveyed regarding the offer of non-native, invasive and threatened native species. The survey was conducted over the entire warm period (from 1 May 2015 to 31 September 2015) while using personal visits, correspondence and interviews to list the species on offer., 'Traditional' ornamental species were offered by 39.1% of surveyed vendors, non-traditional 'marginal' species by 5.6%, common native species by 6.5% and threatened native species by 2.4%., The findings of this study support the hypothesis that 'garden pond' vendors offer non-native species with a risk of biological invasion; moreover, threatened native animals were also on sale. It is probable that a similar situation exists in other countries. It is important for the conservation of native aquatic biota to raise awareness of the need to reduce risk through responsible behaviour of those involved in the pet trade. It is also essential to prohibit stocking of potential invaders and to enforce the illegal capture and sale of native species. [ABSTRACT FROM AUTHOR]

Cherax (Cherax) subterigneus n. sp., is a crayfish endemic to the Aitinjo Lake of West Papua, Indonesia. This species is one of the field-captured species from this region that are exploited for ornamental purposes. Its commonly used commercial name in the pet trade is "Black Orange Tip Crayfish," "Orange Tip Crayfish," or "Red Tip Crayfish." The new species is genetically and morphologically similar to Cherax holthuisi, however, both species can be easily distinguished by certain morphological characteristics or by using sequence divergence, which is substantial, for considering C. subterigneus n. sp. as a valid species. We have also added a note about the probable incorrect subgeneric assignment of the Cherax peknyi and mandatory change of incorrect original spelling of recently described C. gherardii as C. gherardiae. [ABSTRACT FROM AUTHOR]

Bláha, M., Hulák, M., Slouková, J. & Těšitel, J. (2010). Molecular and morphological patterns across Acanthocyclops vernalis-robustus species complex (Copepoda, Cyclopoida).- Zoologica Scripta, 39, 259-268. Morphological traits within Acanthocyclops (Kiefer, 1927) are highly variable, and morphology is too constrained to give complete information of phylogenetic relationships. This study combined morphological and molecular techniques to investigate the taxonomic and phylogenetic relationships of three species of Acanthocyclops ( Acanthocyclops trajani, Acanthocyclops einslei and Acanthocyclops vernalis) inhabiting continental Europe. Morphological indices subjected to principal component analysis (PCA) separated sample populations into three distinct clusters corresponding with the taxonomic status of the species analysed. In addition, the taxonomy status of A. trajani and A. einslei was in agreement with molecular data; however, the intraspecific variation in sequences of 12S rRNA was lower in contrast to specimens morphologically determined as A. vernalis, which were divided into two deeply divergent clades, based on mtDNA sequence divergences. Moreover, high sequence divergence (26%) between these clades indicated the existence of another species that may not be a sister taxon of A. vernalis s.s. Results point to the need for further taxonomic work on Acanthocyclops. [ABSTRACT FROM AUTHOR]

Reliable quantification of aortic regurgitation (AR) severity is essential for clinical management. We aimed to compare quantitative and indirect echo-Doppler indices to quantitative cardiac magnetic resonance (CMR) parameters in asymptomatic chronic severe AR. Methods and Results: We evaluated 104 consecutive patients using echocardiography and CMR. A comprehensive 2D, 3D, and Doppler echocardiography was performed. The CMR was used to quantify regurgitation fraction (RF) and volume (RV) using the phase-contrast velocity mapping technique. Concordant grading of AR severity with both techniques was observed in 77 (74%) patients. Correlation between RV and RF as assessed by echocardiography and CMR was relatively good (rs = 0.50 for RV, rs = 0.40 for RF, p < 0.0001). The best correlation between indirect echo-Doppler and CMR parameters was found for diastolic flow reversal (DFR) velocity in descending aorta (rs = 0.62 for RV, rs = 0.50 for RF, p < 0.0001) and 3D vena contracta area (VCA) (rs = 0.48 for RV, rs = 0.38 for RF, p < 0.0001). Using receiver operating characteristic analysis, the largest area under curve (AUC) to predict severe AR by CMR RV was observed for DFR velocity (AUC = 0.79). DFR velocity of 19.5 cm/s provided 78% sensitivity and 80% specificity. The AUC for 3D VCA to predict severe AR by CMR RV was 0.73, with optimal cut-off of 26 mm2 (sensitivity 80% and specificity 66%). Conclusions: Out of the indirect echo-Doppler indices of AR severity, DFR velocity in descending aorta and 3D vena contracta area showed the best correlation with CMR-derived RV and RF in patients with chronic severe AR. [ABSTRACT FROM AUTHOR]

The aim of this work was to perform tests of genotoxicity and toxicity on samples of riverine sediments from a location subject to motor industry load (car battery production). Together with sediment samples we also collected benthos, biofilm and juvenile fish. Concentration of lead was established in all the samples since the sewage waters discharged from the car battery production plant are heavily polluted with lead. Genotoxicity was tested with two tests of genotoxicity: the SOS chromotest and the Escherichia coli WP2 test. The toxicity of sediments was tested with a test of toxicity performed on a water crustacean Daphnia magna. A profound toxic influence upon benthic organisms was found; a consequence of the river pollution with waste water and flush water from the car battery production plant. This toxic effect was also proven by an aqueous leach from the test performed with Daphnia magna. Both tests of genotoxicity proved a significant genotoxic potential of the sediment samples linked with the growth of the concentration of lead in the sediments (up to 647 mg·kg-1). The content of lead also increased in the biofilm (up to 3.37 mg·kg-1 of dry mass) as well as in the fish bodies (up to 804.5 mg·kg-1 of dry mass). This thesis is the first study of the load imposed on this river as a consequence of the waste water and flush water discharge from the motor industry production plant (car battery production). [ABSTRACT FROM AUTHOR]

Knowledge of spatial genetic variability patterns allows improving conservation actions, translocation regulations, and farming productivity. However, these genetic variability patterns are often considered after issues are observed, long after the beginning of production. By taking into account lessons from other species, we investigate the genetic variability of Perca fluviatilis , a species at a nascent stage of production. The genetic variability has been previously studied but, due to discrepancies between conclusions and methodological limits, the spatial distribution of genetic variability in P. fluviatilis has not been demonstrated conclusively. Here, we characterise the genetic variability across 84 West-Palaearctic sampling sites using mitochondrial and microsatellite markers. We aim to provide (i) a genetically-based population structure that could act as an impetus for further production improvement and (ii) guidelines for translocation regulations. Our analyses show an uneven distribution of genetic variability. Based on inter-populational genetic differentiation, we identify five large geographic scale clusters which are further divided into several subgroups. Local genetic diversity mapping highlights a spatial pattern with several hotspots, which has serious implications in the development of appropriate regulations of translocations. Moreover, we here report an association between genetic differentiations and previously reported zootechnical performances. We ultimately propose guidelines for further investigations of population-specific performances in aquaculture and potentially efficient regulations for policy-makers. • Knowledge of genetic variability patterns is essential for trade and production strategies. • Genetic variability of the European perch is structured in five major clusters. • Different genetic units identified could be associated to distinct phenotypic traits important for the aquaculture industry. • Preserving population specificities requires trade and production regulations. [ABSTRACT FROM AUTHOR]

Methamphetamine (MEA) is commonly detected in municipal wastewater. It causes imbalances in the system of neurotransmitters as well as several other adverse effects on human health. The aim of this study was to investigate bioconcentration and depuration rates at an environmentally relevant concentration of 1 µg·L -1 in Aeshna cyanea nymphs exposed to MEA for six days followed by three days of depuration. The metabolomes of nymphs sampled during exposure and depuration were compared using non-targeted screening. Concurrently, a behavioural experiment was run to evaluate the effect of MEA on movement. Since most samples were below the limits of quantification (LOQs) - MEA was quantified in only four out of the 87 samples and only during the first 24 h of exposure at concentrations at LOQ level - we estimated maximal possible bioconcentration factor (BCF) on 0.63 using the LOQ. An MEA metabolite - amphetamine - was not detected in any sample at levels above their LOQs. From 247 up to 1458 significant down- and up-regulated metabolite signals (p ≤ 0.05) were detected by non-targeted screening during initial times of exposure and depuration. Numbers of significant down- and/or up-regulated signals in metabolomes (p ≤ 0.05) calculated for particular sampling times possibly correlated with the size of the effect on movement recorded at the same times. In the MEA treatment, movement was not significantly greater during exposure (p > 0.05) but was significantly lower during depuration (p < 0.05). This study shows how MEA acts on dragonfly nymphs, an ecologically important group of aquatic insects with a high trophic level., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Using stable carbon and nitrogen isotope analysis (δ 13 C and δ 15 N) to assess trophic interactions in freshwater ecosystems is a well established method, providing insight into ecosystem functioning. However, the spatial and temporal variability of isotope values, driven by environmental fluctuation is poorly understood and can complicate interpretations. We investigated how the temporal variation of stable isotopes in consumers (fish, crayfish and macrozoobenthos) of a canyon-shaped oligotrophic reservoir is associated with environmental factors such as water temperature, transparency, flooded area, and water quality measures. Consumers and their putative food sources were sampled and analyzed for carbon and nitrogen stable isotopes annually, and environmental parameters were measured monthly from 2014 to 2016. Results revealed significant differences in δ 13 C and δ 15 N values in each consumer among studied years. Over the years, fish and crayfish expressed differences in δ 13 C between 3 and 5‰, whereas in zoobenthos differences were 12‰. Variability in δ 15 N was similar across all consumers (2-4‰). Moreover, results suggest that the flooded area of the reservoir was a major driver of δ 13 C stable isotope values variation in consumers, while variation in δ 15 N was not linked to any of the studied environmental factors. Bayesian mixing models further showed significant changes in the origin of detritivorous zoobenthos carbon sources (reversal shift from terrestrial detritus to algae origin) between years with low water level to years with the standard water level. Other species showed only slight differences in food source utilization among years. Our study highlights the importance of environmental factors as sources of variation in consumer's stable isotope values which should be considered especially when studied ecosystem strongly fluctuate in some environmental factor., (© 2023. The Author(s).)

Ornamental aquaculture and the related pet industry are known to be important sources of non-native species worldwide. In the temperate zone, thermal waterbodies are attractive places for irresponsible owners to release unwanted freshwater pets including decapod crustaceans. Several non-native ornamental species have been reported in the thermal locality of Miskolctapolca (a suburb of Miskolc, Hungary). So we surveyed this site in March 2019-November 2021 to update local occurrence records and detect potentially newly released species. A well-established population of Neocaridina denticulata and the occurrence of Caridina cf. babaulti had previously been noted. However, for the first time at this site, we found the shrimps Atyopsis moluccensis, Caridina gracilirostris and C. multidentata, as well as the crayfish Procambarus virginalis, P. clarkii, Cherax quadricarinatus, C. boesemani and C. snowden, and several formally undescribed Cherax species originating from New Guinea. Furthermore, in most species, gravid females carrying eggs were also noticed. Three shrimps, A. moluccensis, C. gracilirostris and C. multidentata, were recorded for the first time in European wild. Further monitoring of this locality and better education of the general public regarding the risks associated with the release of non-native species are strongly recommended., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The growth of cyanobacteria (blue-green algae) is a typical phenomenon in water bodies worldwide. The use of silver carp (Hypophthalmichthys molitrix) to reduce excessive phytoplankton development is controversial. In the case of cyanobacteria, many of which are toxic, understanding their possible digestion mechanism by fish is particularly desirable. A unique methodical approach, which consists of applying intestinal contents or extracts to a cyanobacteria culture, was used. Unicellular cyanobacteria (Cyanothece) were incubated in vitro with bile, contents of different parts of the intestinal tract, and cytosolic and microsomal extracts of the intestinal tissue of silver carp. The abundance of cyanobacteria decreased in all treatments containing either exclusively bile or its combination with intestinal contents. This research provides the first evidence of non-mechanical digestion of cyanobacteria by silver carp. Cyanobacteria incubated with intestinal contents or extracts reached mostly higher abundances than those incubated with the nutrient medium. The existence of non-mechanical digestion mediated via intestinal contents and extracts or its compensation connected with organic substance uptake is discussed.

Identification of animals is often hindered by decoupling of phenotypic and molecular evolutionary rates. The Acanthocyclops vernalis (Fischer, 1853) complex is arguably the most problematic group of cyclopoids and possibly of all copepods, with diversity estimates based on morphology ranging from 2 to 34 taxa. We reconstructed their phylogeny based on one nuclear and three mitochondrial markers, revealing only four species in the Holarctic and always the following sister-species pairs: vernalis-europensis sp. nov. and robustus-americanus. Landmarks for quantitative shape analyses were collected from 147 specimens on five structures commonly used to delineate cyclopoids. Procrustes ANOVA showed small directional asymmetry in all datasets, but large sexual dimorphism in shape and size. Allometry was also highly significant. Principal component analyses of size-corrected data almost completely separated species in morphospace based on the last exopodal and endopodal segments of the fourth leg. These two structures showed the highest amount of covariation, while modularity could not be proven and a phylogenetic signal was only observed in one structure. Spinules and sensilla have a limited use in delineating species here. Calculating mean shapes and the extent of inter and intraspecific phenotypic variability opens new horizons for modern taxonomy.