Search

The crucian carp Carassius carassius (Linnaeus, 1758), is native to many European freshwaters. Despite its wide distribution, the crucian carp is declining in both the number and sizes of populations across much of its range. Here we studied 30 individuals of a putative pure population from Helsinki, Finland. Despite clear external morphological features of C. carassius, an individual was of a higher ploidy level than the others. We therefore applied a set of molecular genetic (S7 nuclear and cytochrome b mitochondrial genes) and cytogenetic tools (sequential fluorescent 4’, 6-diamidino-2-phenylindole [DAPI], Chromomycin A3 [CMA3], C-banding and in situ hybridization [FISH] with both 5S and 28S ribosomal DNA probes) to determine its origin. While all examined characteristics of a diploid representative male (CCAHe2Fi) clearly corresponded to those of C. carassius, a triploid individual (CCAHe1Fi) was more complex. Phylogenetic analysis revealed that the nuclear genome of CCAHe1Fi contained three haploid sets: two C. gibelio and one C. carassius. However the mitochondrial DNA was that of C. gibelio, demonstrating its hybrid origin. The FISH revealed three strong (more intensive) 5S rDNA loci, confirming the triploid status, and an additional 24 weak (less intensive) signals were observed in the chromosome complement of CCAHe1Fi. On the other hand, only two strong and 16 weak 5S rDNA signals were visible on the chromosomes of the CCAHe2Fi male. 28S rDNA FISH revealed four strong signals in both CCAHe1Fi and CCAHe2Fi individuals. CMA3 staining revealed four to six CMA3-positive bands of CCAHe1Fi, while that of diploids contained only two to four. The fact that a polyploid hybrid Carassius female with a strong invasive potential may share morphological characters typical for endangered C. carassius highlights a need to combine genetic investigations of Carassius cryptic diversity with conservation measures of C. carassius in Europe. [ABSTRACT FROM AUTHOR]

We studied growth characteristics of three different spatial groups (epipelagic, bathypelagic, and littoral) of European perch ( Perca fluviatilis) fry occurring simultaneously in Římov Reservoir, Czech Republic. We used the body size analysis as long-term growth indicator and RNA/DNA ratio as short-term growth indicators. The minimum body size as well as minimum RNA/DNA ratio, was found in bathypelagic perch fry (15.7 ± 1.8 and 1.89 ± 0.63 mm, respectively). The littoral perch fry was the biggest with the highest RNA/DNA ratio (19.3 ± 1.5 and 2.53 ± 0.59 mm, respectively). The intermediate values and high variation in both body size and RNA/DNA ratio was found in the epipelagic group (16.9 ± 2.3 and 2.36 ± 0.78 mm, respectively). These results refer to the presence of uniformity in the bathypelagic and littoral groups, and a possible mixing of individuals from different groups in epipelagic zone. Our findings suggest that the spatial distribution of perch fry is most likely dynamic system of continuous shifting of individuals among different groups. [ABSTRACT FROM AUTHOR]

A comparative cytogenetic analysis was carried out in five species of a monophyletic clade of neotropical Cichlasomatine cichlids, namely Cleithracara maronii Steindachner, 1881, Ivanacara adoketa (Kullander & Prada-Pedreros, 1993), Nannacara anomala Regan, 1905, N. aureocephalus Allgayer, 1983 and N. taenia Regan, 1912. Karyotypes and other chromosomal characteristics were revealed by CDD banding and mapped onto the phylogenetic hypothesis based on molecular analyses of four genes, namely cyt b, 16S rRNA, S7 and RAG1. The diploid numbers of chromosomes ranged from 44 to 50, karyotypes were composed predominantly of monoarmed chromosomes and one to three pairs of CMA3 signal were observed. The results showed evolutionary reduction in this monophyletic clade and the cytogenetic mechanisms (fissions/fusions) were hypothesized and discussed. [ABSTRACT FROM AUTHOR]

Fish usually have a simple body shape and many morphological characters can be easily obtained by 2-dimensional image analysis. Measuring errors are often analyzed using data from several researchers or repeated measurements, but the testing of accuracy and repeatability based on different methods has rarely been examined. Here we report the comparison of manual measurements using Proma 150D digital calipers and computer-assisted image analysis in LUCIA software to evaluate the accuracy of both methods and the suitability of digital images for exploration of fish morphology. Eighteen morphometric characters of 20 specimens of Prussian carp were examined by 2 researchers. The mean of the relative bias within and between researchers separately for the manual and computerassisted methods (expressed as a percentage of a character's value) varied from -4.27% to 9.48%. Comparison of interresearcher results using digital caliper, interresearcher results using LUCIA, intraresearcher results using digital caliper, and the 2 methods using manual caliper and LUCIA revealed significant differences in several characters. Only testing of intraresearcher relative bias using LUCIA showed no significant difference. [ABSTRACT FROM AUTHOR]

The karyotype and other chromosomal characteristics the crucian carp (Carassius carassius (Linnaeus, 1758)) were revealed by means of conventional banding protocols (C, CMA3, AgNOR). The diploid chromosome number (2n) in this species was 100. Its karyotype was composed of 10 pairs of metacentric, 18 pairs of submetacentric and 22 pairs of subtelo- to acrocentric chromosomes without any microchromosomes. C-banding identified blocks of telomeric heterochromatin on seven chromosome pairs. The NORs were situated on the p arms of the 14th pair of submetacentric chromosomes and on the p arms of the 32nd pair of subtelo-acrocentric chromosomes; AgNOR-positive signals corresponded to the CMA3-positive signals. These chromosome characteristics may suggest a paleo-allotetraploid origin of C. carassius genome. [ABSTRACT FROM AUTHOR]

The headwaters of five large African river basins flow through the Bié Plateau in Angola and still remain faunistically largely unexplored. We investigated fish fauna from the Cuanza and Okavango-Zambezi river systems from central Angola. We reconstructed molecular phylogenies of the most common cichlid species from the region, Tilapia sparrmanii and Serranochromis macrocephalus, using both mitochondrial and nuclear markers. We found evidence for ichthyofaunal contact and gene flow between the Cuanza and Okavango-Zambezi watersheds in the Bié Plateau in central Angola. Waterfalls and rapids also appeared to restrict genetic exchange among populations within the Cuanza basin. Further, we found that the Angolan Serranochromis cichlid fishes represent a monophyletic lineage with respect to other haplochromines, including the serranochromines from the Congo and Zambezi rivers. This study represents an important initial step in a biodiversity survey of this extremely poorly explored region, as well as giving further understanding to species distributions and gene flow both between and within river basins. [ABSTRACT FROM AUTHOR]

Abstract: Freshwater fishes of the genus Carassius, widespread throughout Europe and Asia, are important aquaculture fishes and include the world''s most important pet fish, the goldfish. The high morphologic similarity between the species, however, has up to now prevented reliable conclusions on their taxonomy, biogeography and introduction history. A phylogeny of the fish genus Carassius based on the cytochrome b sequence of 404 specimens collected from aquaculture and open water localities across Eurasia identifies most of the presently recognised species as monophyletic lineages, but also that at least one lineage exists that does not correspond to any described species. Within Europe, feral populations of Carassius auratus occur mainly in the Mediterranean area and Great Britain, while Carassius gibelio is found in most of non-Mediterranean Europe and some localities in Italy. Carassius langsdorfii has very scattered points of occurrence in at least six European countries. C. auratus and C. langsdorfii are not native to Europe. The populations of C. gibelio in eastern Central Europe and parts of Eastern Europe are considered as resulting from a natural postglacial range expansion, while the rest of Europe was colonised due to anthropogenic impact. The presence of diploid (2n=100) as well as triploid (3n=150) specimens in the three most widespread species indicates that ploidy level is not a character to identify the species of Carassius. A remarkably low genetic divergence in C. gibelio can be the result of clone selection in the gynogenetic populations. In general, our data present the first comprehensive overview about the genus Carassius in Europe based on genetic data. [Copyright &y& Elsevier]

The freshwater characiform fish Prochilodus lineatus is a detritivorous species that has its native distribution area in South America but has been imported to China for aquaculture purposes. This is the first time that it is being reported in Vietnam, both from aquaculture and captured from a river channel. According to local authorities, the species is becoming increasingly important in local aquaculture and its spread can be expected. Keeping in mind the high biomass production in the rivers of its native distribution area, a successful establishment of P. lineatus into Vietnamese fresh waters may exert serious impacts on the local ecosystems. [ABSTRACT FROM AUTHOR]

The article discusses the karyotype diversity of the fish offspring from silver Prussian carp diploid male and triploid female. An overview of the specie's karyotype that features supernumerary chromosomes of the triploid biotype is offered. It reports that the male fish has 100 while the female has 159 which show high level of chromosomal plasticity of the biotype.

Abstract: Goldfish is one of the most important pet and laboratory fishes of the world that is nowadays pan-globally distributed and well known to everybody. Despite the wide phenotypic variability of the ornamental forms, all goldfish are traditionally considered to be Carassius auratus, a species that developed via domestication from the Silver Prussian carp, C. gibelio. However, the postulated monophyly of goldfish has never been proven, and multiple domestication events may have occurred. Here we present the results of a reconstructed genealogy of 49 individuals of the genus Carassius based on unique sequences of mitochondrial gene cytochrome b. The samples originated from different parts of Eurasia and include different varieties of domesticated goldfish as well as feral populations and specimens of other representatives of the genus Carassius. The results indicate that goldfish indeed forms a monophyletic lineage and point on a single domestication event as source of all goldfish varieties. However, the monophyletic goldfish lineage was not nested within the samples of C. gibelio, but formed a sister lineage. [Copyright &y& Elsevier]

Sexual vs. asexual reproduction—unisexual vs. bisexual populations—diploid vs. polyploid biotypes—genetic vs. environmental sex determination: all these natural phenomena are associated with the genus of teleost fish, Carassius. This review places emphasis on two Carassius entities with completely different biological characteristics: one globally widespread and invasive Carassius gibelio, and the other C. carassius with a decreasing trend of natural occurrence. Comprehensive biological and cytogenetic knowledge of both entities, including the physical interactions between them, can help to balance the advantages of highly invasive and disadvantages of threatened species. For example, the benefits of a wide-ranged colonization can lead to the extinction of native species or be compensated by parasitic enemies and lead to equilibrium. This review emphasizes the comprehensive biology and cytogenetic knowledge and the importance of the Carassius genus as one of the most useful experimental vertebrate models for evolutionary biology and genetics. Secondly, the review points out that effective molecular cytogenetics should be used for the identification of various species, ploidy levels, and hybrids. The proposed investigation of these hallmark characteristics in Carassius may be applied in conservation efforts to sustain threatened populations in their native ranges. Furthermore, the review focuses on the consequences of the co-occurrence of native and non-native species and outlines future perspectives of Carassius research. [ABSTRACT FROM AUTHOR]

Afrotropical inland waters are highly diverse ecosystems; however, they remain poorly studied, especially for rotifers. Here, we contributed to the knowledge of the rotifer species richness in the largely understudied African countries of Angola and Ghana. We assessed the roles of habitat type and a suite of abiotic environmental factors in determining rotifer species richness of Ghana. A total of 37 sites (Ghana 32, Angola 5) in 19 water bodies from a variety of aquatic habitat types were sampled. In Ghana, we identified 118 taxa (105 species or subspecies level, 13 identified to genus). We identified 15 taxa (13 species) in the Angola samples. For Ghana, 100 of 118 (~85%) taxa were new records for the country, of which 13 species (~11%) were also new records for Africa. Nearly all the species (~93%) were new records for Angola. Species richness was positively correlated with conductivity and reservoir habitat type and negatively with pH. Redundancy analysis (RDA), conducted at the species level for the Ghana dataset, indicated suites of species associated with latitude, longitude, temperature, TDS, or pH. We also evaluated the effect of climate on species distribution in 27 African countries by conducting a review of all reports from Africa to determine factors associated with species richness. A Spearman's correlation confirmed a significant positive correlation between the number of rotifer species and the number of climatic regions (R = 0.53, p < 0.001) for certain countries, based on species distributions in relation to Köppen–Geiger climate regions. This fact validates the environmental heterogeneity hypothesis for African rotifers. Lastly, we predicted that rotifer species richness in Ghana, as a country with a tropical climate, could approach ~190 taxa, while in climatically heterogeneous Angola we predict ~200 taxa. This study contributes to our knowledge of rotifer biogeography and species richness patterns in Africa. [ABSTRACT FROM AUTHOR]

The use of digital data sources, such as social media, in iEcology has opened up new opportunities for research on species distribution and biological invasions. Invasive species can cause significant damage to biodiversity and ecosystem services, making early detection and intervention crucial. Ornamental fish species are a particular concern, as many have been imported to India for aquaria and have caused direct damage to local biodiversity. South American invasive catfish species belonging to the family Loricariidae have been introduced to many parts of the world outside their natural range, including India. Despite a lack of published records, this study used social media and internet sources to identify 28 sites of occurrence of suckermouth armoured catfish in the River Krishna basin across four Indian states. Through morphological and genetic analysis, the invasive loricariid fish collected from the River Krishna basin at Bhigwan was confirmed to be Pterygoplichthys pardalis. In addition, sentiment analysis of social media content and other internet sources revealed that 60.71% of individuals perceive the introduction of suckermouth armoured catfish to their region as a threat. This insight could prove advantageous as society is more likely to support eradication activities necessary to prevent further damage to the ecosystem. [ABSTRACT FROM AUTHOR]

Social deprivation early in life affects further individual development and leads to irreversible behavioural alterations later in life. Although the syndrome is well-studied in vertebrates including humans, its presence in invertebrates has been described only in eusocial insects and cockroaches. Here we show the first evidence of social deprivation in subsocial decapod crustaceans, based on analysis of video-recorded agonistic encounters of juvenile red swamp crayfish (Procambarus clarkii, Girard). In comparison with maternally incubated juveniles, isolated crayfish had altered repertoires, numbers and frequency of agonistic interactions similar to those described in vertebrates. Our results support the view on the syndrome of social deprivation as a ubiquitous trait in species with developed maternal care across diverse taxa. [ABSTRACT FROM AUTHOR]

We provide a general overview of spatial distribution and the economic situation of aquaculture enterprises in Czechia (the Czech Republic) in terms of revenues, profitability, work productivity, indebtedness and grants. We analysed data available in the State Veterinary Administration and information system of the State Agricultural Intervention Fund. The most significant fish producers (enterprises) are located in the regions of South Bohemia. Aquaculture sector profitability and enterprises profits have been moderately rising since 2010. The profitability in 2015 is roughly the same as that in 2005. The amount of provided grants showed a higher value than the generated average annual profits. The enterprises were not able to generate sufficient resources to finance investments without grants resources. Enterprises that realised financing for larger investments from bank credits showed relatively high levels of indebtedness (micro-enterprises at 95.5%). On the contrary, work productivity was the highest for micro-enterprises. Micro-enterprises had the largest share of revenues in relation to the number of employees. Each group of enterprises is considerably specific and needs an individual approach for the subsequent evaluation. [ABSTRACT FROM AUTHOR]

Carbon nanofibers, recently recognized pollutants, have been heavily used among the nanomaterials in many industries. Due to the poor suspension-stability, carbon nanofibers tend to sediment at the bottom of waterbodies and hence can be consumed by the bottom-dwellers. The current investigation evaluates the impact of carbon nanofibers at concentrations between 0.1 and 10 mg L−1 on the common bottom dweller spiny loach Lepidocephalichthys thermalis inhabiting Indian rivers. Carbon nanofiber exposure elevated the activities of the hepatic antioxidant enzymes superoxide dismutase, catalase, peroxidase and glutathione S-transferase, as oxidative stress markers. The fish behaviour patterns were examined by testing the effect of carbon nanofibers on predator recognition ability using kairomones, conspecific alarm cues, and dietary cues. The carbon nanofiber-exposed fish showed a loss of predator-recognition abilities. The results collectively demonstrated the carbon nanofiber driven hepatic oxidative damage and impaired predator-recognition ability in L. thermalis. The investigation, first of its kind, highlights the toxic potential of the carbon nanofibers on benthic fishes. [ABSTRACT FROM AUTHOR]

The seasonality of fish marketing is a very important character for aquaculture production. We analysed data regarding the situation at the Czech market in 2015 and 2016 available in the information system of the State Agricultural Intervention Fund. The most significant volumes of freshwater fish were traded by traditional pond aquaculture companies (TPA) and approx. 1 / 3 of the all-year production was sold at the end of the year (December). Another significant time when the supply of live fish from the TPA on the domestic market slightly increased was in March and then in April, i.e. before Easter, which represented approximately one fifth of all aquaculture production. The weakest periods in terms of marketing fish of TPA were the beginning of the year, i.e. during the first two months (January and February) and the period from May to September. On the contrary, the situation was different in intensive fish aquaculture companies (IA) which had the most significant volumes traded between April and September and then in November and December. However, the sold volume of fish from IA was not strictly concentrated in a single period. [ABSTRACT FROM AUTHOR]

We provide a first investigation of fish species composition, sex ratios, age, length-weight relationships and growth models in Saghamo Lake located in Javakheti highland (Georgia). In total 713 specimens belonging to 8 species were collected included non-native Coregonus albula, Carassius gibelio and native Alburnoides bipunctatus, Squalius cephalus, Capoeta capoeta, Romanogobio persus, Salmo cf. caspius and Barbus lacerta, among which later two were recorded for the first time in the lake. In overall, relative abundances of all species is low while some species may not be presented with viable populations. Deviation from expected sex ratio, growth at age and age structure indicates severe anthropogenic pressure as a potential driver of fish community degradation in the lake. [ABSTRACT FROM AUTHOR]

Nematode parasites of the family Anisakidae infect definitive hosts, such as fish‐eating birds and mammals, through primary intermediate hosts like copepods and secondary intermediate hosts like fishes. However, consumption of raw or undercooked fish can lead to nematode infection called anisakidosis in humans. We observed the presence of nematode infection in hillstream loaches of families Cobitidae and Nemacheilidae available for human consumption in the local markets in the northern parts of Western Ghats, India. Scanning electron micrograph and genetic identification employing mitochondrial cytochrome oxidase subunit II, identified the nematode to the genus Contracaecum. Histology of infected host revealed the presence of the parasite in muscles. Antioxidant enzyme analysis of host liver suggested that infection leads to oxidative stress in the fish. We suspect that a gradual increase in parasite infection of the loaches in the last decade could be attributed to various anthropogenic stressors that are altering riverine habitats. Since loaches are consumed by tribal people who often prepare the fish without degutting and possibly undercooked, there is a potential threat of human infection. [ABSTRACT FROM AUTHOR]

The present study provides a comprehensive osteological description of Pachypterus khavalchor from the family Horabagridae. Nine individuals of P. khavalchor representing both males and females collected from the type locality were cleared and double-stained to provide a description of osteological characteristics. The presence of an almost straight dorsal roof to the cranium, a long and protruding premaxilla with numerous rows of tiny, villiform teeth, a spoon-like lower jaw with villiform teeth projecting outward, and five long and ossified ceratobranchials, with the 5th ceratobranchial containing a set of 80 to 90 conical teeth, sheds light on the ecomorphological adaptation in P. khavalchor that may have led to the evolution of lepidophagy. Furthermore, a slight difference in the structure of the complex hypurapophysis was observed between males and females. The information on the osteology of the Khavalchor catfish forms a baseline for taxonomic research of the entire Horabagridae family comprising four genera with ten species distributed in Asia. [ABSTRACT FROM AUTHOR]

Aquatic invasions are one of the major threats for freshwater ecosystems. However, in developing countries, knowledge of biological invasions, essential for the implementation of appropriate legislation, is often limited if not entirely lacking. In this regard, the identification of potentially invasive nonnative species by risk screening, followed by a full risk assessment of the species ranked as higher risk, enables decision-makers to be informed about the extent of the threats posed to the recipient (risk assessment) area. In this study, 32 non-native extant and horizon fish species were screened for their risk of invasiveness under current and predicted climate conditions for the South Caucasus - a biodiversity and geopolitical hotspot that includes the countries of Armenia, Azerbaijan and Georgia. Overall, the number of very high-risk species increased from four (12.5%) under current climate conditions to 12 (37.5%) under predicted climate conditions. The highest-risk species under both conditions included the already established gibel carp Carassius gibelio and topmouth gudgeon Pseudorasbora parva, the locally translocated pikeperch Sander lucioperca and the horizon North African catfish Clarias gariepinus. Under predicted climate conditions, a very high risk of invasiveness was predicted also for the translocated threespined stickleback Gasterosteus aculeatus and Eurasian perch Perca fluviatilis, for the already established eastern mosquitofish Gambusia holbrooki, ruffe Gymnocephalus cernua, sharpbelly Hemiculter leucisculus and Nile tilapia Orechromis niloticus, and for the horizon pumpkinseed Lepomis gibbosus and largemouth bass Micropterus salmoides. Future research on the non-native species in the South Caucasus should be conducted both country- and region-wide and should account not only for the high biodiversity, but also for the critical geopolitical situation affecting the study area. [ABSTRACT FROM AUTHOR]

The article presents a study which examines crayfish remains as the earliest evidence of prehistoric human consumption during the Neolithic period. The study uses accelerator mass spectrometry to examine the radiometric 14C dating of the settlement at the locality of Horákov-Čtvrtky in Brno, Czeck Republic. Results of the study show clear evidence of crayfish consumption of humans during Prehistoric Age.

The article presents research which examined the environment of loaches in the provinces of Cao Bang and Lang Son in Northern Vietnam. The researchers collected the maximum number of fish species available to loaches at each locality. They also found ten loach species and at least of these represent underscribed species. They concluded that the regions' ichtyofauna still hold a hidden diversity and strong anthropogenic pressure that contribute to the survival as well as diversity of the loaches species that they have observed.

Additional risks arise from potential species misidentification generated by data producers, experts assessing digital data, or by automated species identification software (Jari'c et al. 2020). Digital data can also provide information on distributions, spread dynamic, life history, and impacts of invasive non-native species within the framework of iEcology (Jari'c et al. 2020). This could greatly increase the volume of available information on invasive non-native species, especially once web crawlers are used more commonly to automatically scrape the web, identify and validate species' mentions, and flag range expansions. Invasion culturomics and iEcology represent promising options to track and study invasions as well as societal attitudes and interactions with invasive non-native species. [Extracted from the article]

Nothing in excess is good: Double pelvic fin malformation in the wild-caught hill stream loach, Indoreonectes evezardi (Day, 1872) from biodiversity hotspot of India Pelvic fins are supported by the pelvic radials in both fins of the anterior pelvic fin pair, while it is missing in left posterior pelvic fin. There are eight fin rays in the anterior pair of pelvic fins and seven in the posterior pair of pelvic fins in the malformed individual, as opposed to the normal individual having nine pelvic fin rays (Figure 1g). Keywords: conservation; industrial effluents; life-history traits; osteology; pollution EN conservation industrial effluents life-history traits osteology pollution 326 330 5 03/15/21 20210401 NES 210401 INTRODUCTION Malformations, particularly affecting fins, are not uncommon in fish and are well-known in both wild and cultured fish species (Kaushik, 1960; Noble et al., 2012). [Extracted from the article]

The ongoing digital revolution in the age of big data is opening new research opportunities. Culturomics and iEcology, two emerging research areas based on the analysis of online data resources, can provide novel scientific insights and inform conservation and management efforts. To date, culturomics and iEcology have been applied primarily in the terrestrial realm. Here, we advocate for expanding such applications to the aquatic realm by providing a brief overview of these new approaches and outlining key areas in which culturomics and iEcology are likely to have the highest impact, including the management of protected areas; fisheries; flagship species identification; detection and distribution of threatened, rare, and alien species; assessment of ecosystem status and anthropogenic impacts; and social impact assessment. When deployed in the right context with awareness of potential biases, culturomics and iEcology are ripe for rapid development as low-cost research approaches based on data available from digital sources, with increasingly diverse applications for aquatic ecosystems. [ABSTRACT FROM AUTHOR]

We present a critical checklist of freshwater fish species found so far in the countries of Armenia, Azerbaijan and Georgia. In total 119 freshwater fishes are recorded. There are 40, 86 and 96 species currently known for Armenia, Azerbaijan and Georgia respectively. From these 119 species, seven are endemic and seven species are alien. From the alien species, only three (Carassius gibelio, Gambusia holbrooki and Pseudorasbora parva) can be considered as widespread and invasive. There are four species (Gasterosteus aculeatus, Gobio artvinicus, Perca fluviatilis and Salmo gegarkuni) that are translocated within the region. Seven species are confirmed or recorded for the first time including G. artvinicus and Oxynoemacheilus veyselorum for Armenia, Azerbaijan and Georgia, Capoeta kaput and Rhinogobius lindbergi for Azerbaijan and Georgia, Capoeta razii for Azebaijan, Oxynoemacheilus cemali and Squalius agdamicus for Georgia. In this checklist, Acipenser colchicus is treated as a synonym of Acipenserpersicus. Sand smelts of the Black and Caspian Sea basin are identified as Atherina caspia and Clupeonella caspia is treated as a synonym of Clupeonella cultriventris. Coregonus sevanicus is listed as Coregonus sp. until the situation of Sevan whitefish is better understood. Capoeta sevangi and Capoetaekmekciae are synonyms of Capoetacapoeta. The fish often identified as Capoeta capoeta gracilis from rivers south of the Kura most likely belong to C. razii. The Black and Caspian Sea Rutilus populations are treated as conspecific, therefore R. kutum is a junior synonym of R. frisii. Oxynoemacheilus veyseli is valid as O. veyselorum. We list the alien Rhinogobius species as R. lindbergi, however the name is provisional and needs further confirmation. All Squalius species from the Kura River drainage are identified as S. agdamicus, however in the Aras, it is replaced by S. turcicus. Squalius orientalis is treated as a valid species restricted to the eastern Black Sea basin. The four forms of Lake Sevan trout (Salmo ischchan, S. gegarkuni, S. danilewskii and S. aestivalis) are treated as valid species, two of them (S. ischchan and S. danilewskii) are extinct. Rutilus sojuchbulagi from Azerbaijan is also extinct. [ABSTRACT FROM AUTHOR]

Trade with marine species as ornamentals is an important sector of the international pet trade. The vast majority of these species are collected from the wild and one of the top supplying countries is Indonesia. Detailed evidence on trade with marine resources in Indonesia is lacking or it is hardly accessible. Moreover, the exploitation of ornamental species seems to be mostly uncontrolled. This study presents detailed characteristics of such trade for Indonesia, including the offered species, their sizes, prices, and conservation status, based on data and information obtained from wholesalers in 2018. The main provinces of marine wildlife collecting are also identified. In total, 777 marine vertebrate and invertebrate species were traded, belonging to 174 families including two species classified as endangered: Banggai cardinal fish (Pterapogon kauderni) and zebra shark (Stegostoma fasciatum). Commonly traded was red lionfish (Pterois volitans), known to be a successful invader. The volume of ornamental marine fish exported from Indonesia in period 2015–2019 was 3 353 983 kgs sold for 33 123 218 USD. The province of Bali was identified as the main exporter of ornamental marine fish within Indonesia. These findings should help to establish sustainable exploitation of marine resources in relation to conservation and wildlife management. [ABSTRACT FROM AUTHOR]

Abstract: Freshwater fishes of the genus Carassius are widespread throughout Eurasia, but notoriously difficult for identification by morphological characters, leaving their systematics in a vague state and the validity of several species is unclear. Consequently, genetic data are used to identify the evolutionary units within this genus. Here, we present an analysis of the genus Carassius in Vietnam and south‐eastern China based on phylogenetic reconstruction using the mitochondrial cytochrome b gene and the nuclear S7 gene. We found two lineages in Vietnam with high supports in the nuclear as well as the mitochondrial dataset. One lineage corresponds to the species Carassius auratus, and one lineage represents an independent evolutionary unit. We test whether the lineage may correspond to the species that has once been described as Carassius argenteaphthalmus. The main character for identification, the color of the eye rim, did not distinguish two clades from each other. Considering the absence of genetic data, the imprecision of the original description, and the absence of all type specimens, the name of C. argenteaphthalmus is considered to be a nomen dubium. [ABSTRACT FROM AUTHOR]

The marbled craynsn ( Procambarus fallax f. virginalis) has become one of the potentially most dangerous nonindigenous crayfish species spreading in European countries and elsewhere. This taxon reproduces parthenogenetically and recently has been verified as a vector of the crayfish plague pathogen. Here, we report on two established populations of marbled crayfish in the Czech Republic. The marbled crayfish was observed during autumn 2015 in an urban pond connected by sewer piping with the Rokytka brook near its mouth to the Vltava River in Prague. Subsequently, three adult females, two of them having well-developed glair glands and oocytes, were captured in this pond during spring 2016, suggesting successful overwintering of the local population. Furthermore, four adult females were captured in an artificial pond at the Radovesická lignite spoil heap in the vicinity to the industrial conurbation of Bílina in summer 2016; one of them carried eggs. We tested these for the presence of the crayfish plague pathogen Aphanomyces astaci, with negative results. The introduction pathway for both populations is most likely a release from private aquaria, as these sites are popular for recreation activities. Our findings substantiate previous predictions that conurbations are likely to be the primary areas for marbled crayfish introductions. [ABSTRACT FROM AUTHOR]

Sustainable plastic-waste management is becoming increasingly challenging as enormous loads of plastic debris regularly accumulate in susceptible ecosystems. The microplastic (MP) particles generated from these plastic wastes are imposing additional threats to these ecosystems due to their small size as well as their ability to adsorb and carry toxic chemicals. The current investigation deals with one such MP-originated toxicant, diethyl phthalate (DEP), and its impact on two species of freshwater loaches from the Western Ghats of India, Lepidocephalichthys thermalis and Indoreonectes evezardi. The MP samples were collected from the sediments of the Mula River and characterized using spectroscopic methods and scanning electron microscopy. Polymers, such as polyvinyl chloride and polypropylene, were identified in the collected MPs. GC-MS analysis of the MP extracts revealed the presence of DEP, confirming the MP waste as a potential source of DEP pollution. Further, to evaluate the effect of DEP on survival of selected loaches, L. thermalis and I. evezardi were exposed to DEP concentrations (18.75–300 mg L−1) and the lethal DEP dose (LC 50) was estimated to be 44.53 mg L−1 for L. thermalis and 34.64 mg L−1 for I. evezardi. Fishes were further exposed to sub-lethal DEP concentration for one day (Short term exposure: STE) or eight days (Long term exposure: LTE) to analyze the histological condition and oxidative status of the liver in response to DEP treatment. Histology revealed congestion of sinusoids and vacuolization after the LTE. Higher lipid peroxidation levels were also measured in the livers of both species treated with DEP, which indicated DEP-mediated oxidative damage. The antioxidant enzymes including superoxide dismutase, catalase, peroxidase and glutathione-S-transferase displayed elevated activities in response to STE and LTE of DEP. Collectively, the results demonstrate that MPs in the Mula River are a potential source of DEP. The findings also show that DEP exposure can be fatal to freshwater fishes such as loaches, possibly by causing increased oxidative damage to the hepatic system. [Display omitted] • Microplastics (MPs) were isolated and characterized from Mula River sediments in India. • GC/MS analysis revealed that MPs were a source of diethyl phthalate (DEP). • Hepatic damage was observed in freshwater loaches after DEP exposure. • DEP exposure increased the activity of antioxidant enzymes in freshwater loaches. [ABSTRACT FROM AUTHOR]

Ornamental aquaculture is an economically important industry with many enthusiasts worldwide. Much of the supply for the industry is provided by individuals and businesses in tropical countries because many ornamental species originated in the tropics. But Czechia, a temperate region in Central Europe, is an exception. Czech suppliers have significantly influenced the global freshwater ornamental aquaculture market for decades. Here we present and discuss the history of ornamental aquaculture in Czechia considering its geopolitical background, social status and history, pet-trade trends, overlapping to research activities, public education, and related risks and threads. We list the most traded and exported species, and list species that rarely reproduce in captivity, but that are successfully bred for commercial purposes by Czech producers globally, we introduce the term "Czech aquarium phenomenon" to describe the substantial economic and scientific importance of Czechia in ornamental aquaculture. Given that the diversity and volume of species traded are vast, we suggest the importance of this phenomenon for consideration to key stakeholders who design aquaculture policies, including the management of invasive alien species and ex-situ conservation programs for endangered species. • Most ornamental aquatic organisms originate from tropics. • Czechia is the only country in the temperate zone among the top suppliers. • Ornamental aquaculture in Czechia has a long history. • Czechia influences global ornamental aquaculture by local production, import and export. • The term "Czech aquarium phenomenon" was proposed in this regard. [ABSTRACT FROM AUTHOR]

We monitored concentrations of Cd, Cu, Mn and Zn in acantocephalan parasites (Acanthocephalus lucii) and its final host (Perca fluviatilis). The concentrations in parasites were found to be significantly higher than those found in the muscle, gonads and liver of fish host. The bioaccumulation factor values (BF=C parasite/C host muscle) were 194, 24.4, 2.2 and 4.7 for Cd, Cu, Mn and Zn, respectively. This suggests a benefit for the host due to the high accumulation of toxic cadmium. [Copyright &y& Elsevier]