ARPHA Preprints
Not a member yet
49208 research outputs found
Sort by
A comparative study of pelagic and benthic resource use by invasive gibel carp (Carassius gibelio) and native crucian carp (Carassius carassius)
No full textThe efficient exploitation of available food resources is important for the prosperity and survival of any species. It influences not only growth and reproduction, but also the competitiveness of a species in the ecosystem. The native crucian carp (Carassius carassius) is currently considered critically endangered in the Czech Republic, primarily due to competitive pressure from the invasive gibel carp (Carassius gibelio). The underlying mechanisms driving this strong interspecific interaction are still poorly understood. This study explores differences in pelagic and benthic foraging between these two species under contrasting environmental conditions (clear vs. turbid water), using controlled laboratory experiments. To identify species-specific differences in foraging efficiency as determined by prey type and size, we conducted manipulative predation experiments using model prey organisms consisting of two size classes of Daphnia galeata and larvae of Chironomus plumosus. The results demonstrated that gibel carp exhibited significantly higher prey capture rates than native crucian carp in both pelagic and benthic prey types, suggesting a greater potential to exploit and successfully utilize available food resources. The invasive gibel carp also displayed higher levels of activity and boldness, supporting its propensity for more aggressive exploitation of the environment. Such superior foraging efficiency of invasive gibel carp may be a major factor contributing to the decline of crucian carp populations in small water bodies where both species co-occur
Designing critical pond infrastructure for conservation of wetland fishes in the Czech Republic
No full textRiver regulations and ill-considered steps in fisheries and aquaculture management have led to substantial changes in the original Czech ichthyofauna. These changes are particularly noticeable in species that are not economically important such as crucian carp (Carassius carassius), sunbleak (Leucaspius delineatus), or weatherfish (Misgurnus fossilis). Compared to original fish species with economic importance, there is no organized support for the repatriation of these small fish species. Thus, the goal of this large-scale project is to secure the remaining populations of these species, with crucian carp serving as a flagship species. The citizen science approach was used to identify remaining populations of crucian carp and their populations were subjected to genetic testing. A collaboration between authors and Forests of the Czech Republic was set to secure 30 pool-like ponds spanning across Czech Republic covering each region, aiming to cover potential differences in genetic variability among remaining populations. This approach provides critical infrastructure without presence of invasive fish species, thus enabling native wetland fish repatriation and natural reproduction. These ponds will serve as centres for the reintroduction of these fish species regionally, thus minimizing risk of loosing important genetic diversity during repopulation measures for these invasive species. Our goal is to obtain a permanent source of genetically verified fish, and the surplus of their populations will be locally spread in cooperation with fishermen and citizen scientists within individual regions. This contribution demonstrates how citizens can be embedded in effective conservation of small fish species with no economic importance
Towards the Establishment of Conservation Units of the Endangered European Weatherfish (Misgurnus fossilis)
No full textThe European weatherfish (Misgurnus fossilis) has suffered significant declines across its distribution area due to extensive anthropogenic habitat destruction. As a result, many European countries classify the species currently as ‘endangered’ or ‘critically endangered’. Misgurnus fossilis is also known for exhibiting exceptionally low genetic diversity throughout Europe if compared to other freshwater fish species. This study analyses the genetic diversity of M. fossilis based on mitochondrial (mtDNA) and nuclear DNA (nuDNA) sequence data from 30 populations across Central Europe and two from Eastern Europe. Both datasets reveal that populations from the Czech Republic, Austria, and Bavaria form a genetically distinct lineage, separate from other European populations. This lineage is found in three major river basins — Elbe, Danube, and Oder — but is geographically isolated by surrounding mountain ranges. Despite at least two natural contact zones between the CZ-A-Bav lineage and other groups and a relatively small genetic distance between them, the two should be recognised as separate conservation units. In Austria, Bavaria, and the Czech Republic, the populations are typically geographically extremely limited and small, making them highly vulnerable to the ongoing landscape and climatic changes leading to the disappearance of surface water. These populations are experiencing a rapid and alarming decline. Given their precarious status and ecological uniqueness, this Central European conservation unit should be classified as critically endangered and prioritised for protection. Urgent habitat conservation efforts are essential, not only for M. fossilis but also for the broader ecological community that coexists with it
Is there any chance in a three-front war? The past, present and possible future of muddy water fish species in Hungarian waters
No full textIn this presentation we focus on key aspects that have affected wetland fish species in the past and affect them presently, as well as new challenges they are likely to face in the future. Numerous factors have influenced the fish fauna of the Carpathian Basin over the centuries. The first major changes were caused by river regulation, which began in the early 18th century. This was followed by the introduction of non-native species through both illegal and legal stocking and their natural spread. Finally, increasingly rapid climate change has begun to cause ever greater problems. Due to the combined effects of these three processes, muddy water fish populations are now on the edge of extinction. Here, we demonstrate how current maintenance practices are destroying the remaining populations of weatherfish (Misgurnus fossilis) in the lowland stream and channel network systems. Additionally, the co-occurrence of invasive marbled crayfish (Procambarus virginalis) and several invasive fish species (e.g. Chinese sleeper Perccottus glenii, Jaguar guapote Parachromis managuensis, Eastern mosquitofish Gambusia holbrooki) has affected the population of the European mudminnow (Umbra krameri) in the western drainage region of Lake Balaton. We emphasise the challenge posed by non-native species, which will require sustained management in the future, as well as changes in water management practices and angling stocking programs. Education programmes targeting all age groups, from children to adults, are also required. All of these measures are urgently needed to ensure the preservation of muddy-water fish species in Hungarian waters
The Distribution of the Belica Leucaspius delineatus and the Crucian Carp Carassius carassius in Hungary over the Past Fifty Years and the Threats to the Persistence of Their Populations
No full textIn the Carpathian Basin, large-scale water regulation projects in the 18th century – primarily the drainage of extensive marshlands – led to a substantial reduction of wetland habitats, which in turn caused significant declines in the populations of marsh-dwelling fish species. The Belica Leucaspius delineatus is also among these rare marsh fauna elements, for which distribution data are still scarce. In Hungary, the Belica is currently classified as “protected”. Its most typical habitats are marshes and wetland areas where it co-occurs with other threatened marsh fish species such as Tench Tinca tinca, Crucian Carp Carassius carassius, Weatherfish Misgurnus fossilis, and Mudminnow Umbra krameri. Additionally, populations have been recorded from mid-mountain streams, where it coexists with species such as Chub Squalius cephalus, Danube Gudgeon Gobio obtusirostris, and Stone Loach Barbatula barbatula. In several cases, it has also been found in small lowland drainage channels, degraded habitats, and in small pits or oxbows within the floodplains of larger rivers. The Crucian Carp Carassius carassius, became the second most endangered fish species in Romania by the 1990s, after the Romanichthys valsanicola. Unfortunately, the situation in Hungary is similar. The invasive Prussian Carp Carassius gibelio is now considered the most common fish species in Hungary, and has spread even into isolated marsh habitats where the Crucian Carp is gradually being displaced. The Crucian Carp has disappeared from many sites, especially oxbows, due to fishing exploitation and illegal introductions of the Prussian Carp. Unfortunately, the Crucian Carp does not currently enjoy legal nature conservation protection in Hungary, although its capture is prohibited year-round. Field surveys were conducted primarily using low-voltage battery-powered electrofishing gear. Data collection was often carried out under challenging field conditions, caused partly by dense submerged and emergent aquatic vegetation, and partly by deep soft sediments. At most survey sites, photographic documentation of the habitat was taken, the most common water quality parameters were measured (pH, dissolved oxygen content, conductivity, water temperature), and the number of individuals of captured species was recorded using a digital voice recorder. In this presentation, we aim to provide an overview of the distribution of these two endangered marsh fish species in Hungary over the past 50 years and to identify the main threats to the persistence of their populations
Round goby population differentiation across river barriers in Central Europe
No full textRiver barriers such as hydropower dams and weirs can negatively affect river ecosystems by disrupting connectivity and reducing biodiversity. However, such barriers could also limit the spread of invasive species. Here, we used a spatial population genetics approach to test whether river barriers act as a hindrance to gene flow in the invasive round goby (Neogobius melanostomus Pallas, 1814). We sampled gobies from four different rivers across their invasive range in Central Europe (the Danube, Dyje, Morava, and Rhine rivers), with locations on either side of eight major river barriers. Using microsatellite genotyping, we found that round goby populations were differentiated with increasing number of river barriers and with increasing distance between sampling sites, depending on the river system in focus. We found significant population differentiation across three individual barriers, but no clear indication that this was related to barrier type as barriers were highly diverse. We also found reduced genetic diversity in populations that were more recently established. Our findings suggest that successive river barriers can sometimes slow the spread of round goby. Further research on the features of barriers that hinder round goby movement will help to design barrier passage solutions that will both limit spread of this invasive species and maintain connectivity for the native fauna
New insights into the phylogeny of Tetrigoidea (Insecta, Orthoptera), with the announcement of the first mitogenome of the genus Phaesticus
No full textThe mitochondrial genome (mitogenome) has been widely used to infer the phylogeny, origin and evolution of insects. Although mitogenomic data have been used to study the phylogenetic relationships of Tetrigoidea (Orthoptera), larger sample sizes were also essential to explore the detailed phylogenetic relationships of these taxa. In this study, two complete mitogenomic sequences were sequenced from Phaesticus moniliantennatus (formerly Flatocerus daqingshanensis and F. nankunshanensis). The mitogenome sequences were assembled, annotated and analyzed. The length of the mitogenomes was 16,147 and 16,224 bp, and the nucleotide composition was A>T>C>G, A-skew and C-skew. Large intergenic regions between trnS(ucn) and ND1 were identified with a length of 191–233 bp. Phylogenetic analyses showed that Batrachideinae formed the basal position of Tetrigoidea, followed by Tripetalocerinae. The monophyly of several subfamilies was not supported. Within Tetriginae, P. moniliantennatus clustered with a clade containing Systolederus spicupennis, S. hainanensis and S. zhengi (Metrodorinae), indicating their closer phylogenetic relationship. The divergence time results indicated that Batrachideinae diverged at 170.96 Ma and Tripetalocerinae diverged at 149.36 Ma. And the divergence time between P. moniliantennatus and the closely related Systolederus clade was 87.06 Ma. These results represent the available mitogenome sequences of the genus Phaesticus and provide a valuable data resource for reconstructing phylogenetic relationships and studying the differentiation of Tetrigoidea species
Revision of the Chinese species of the genera Genimen and Genimenoides (Orthoptera, Acrididae)
No full textBased on an examination of types and additional materials, Chinese species in the genera Genimen and Genimenoides were reviewed. As a result of our study, Genimen burmanum Ramme, 1941 was shown not to occur in China, the species Genimen zhengi Mao, Ren & Ou, 2010, syn. nov. was synonymized under Genimen yunnanensis Zheng, Huang & Liu, 1988, and Genimenoides vittatum Mao, Ren & Ou, 2010 was transferred to Genimen, as the new combination Genimen vittatum (Mao, Ren & Ou, 2010), comb. nov. An updated species key for Genimen is provided
Two new species and a new record of the genus Nephrotoma Meigen, 1803 (Diptera, Tipulidae) from Northwest China, with a key to species in the region
No full textThis study describes two new species of the genus Nephrotoma Meigen, 1803 from Northwest China, N. furvligulata sp. nov. and N. palacea sp. nov., with full descriptions and illustrations. It also records N. lunulicornis (Schummel, 1833) for the first time in China. Updated descriptions and illustrations are also provided for three previously known species, N. geniculata Yang & Yang, 1987, N. joneensis Yang & Yang, 1990, and N. ligulata Alexander, 1925, incorporating new morphological details. An identification key to all Nephrotoma species currently recorded in Northwest China is included to facilitate further research
Monstrilloid copepods (Crustacea, Copepoda) in the U.S. National Museum of Natural History, Smithsonian Institution: updated redescriptions of Mexican species of Monstrilla Dana
No full textThe species of monstrilloid copepods (Monstrilloida: Copepoda: Crustacea) from Mexico that were deposited by the author in the collections of the National Museum of Natural History, Smithsonian Institution in the 1990s are redescribed based on updated descriptive standards. This study includes the re-examination and redescription of type specimens of several species of Monstrilla Dana, 1849. The redescriptions were prepared following currently used standards that were set after these species were described. This revision reveals previously unnoticed characters that improve the morphological details of these species; new comparisons of some of these species are also provided. This work will allow a more complete and accurate analysis of these Mexican species