Freshwater Molluscs Research Articles

Recent and future distribution of the alien Chinese pond mussel Sinanodonta woodiana (Lea, 1834) on the European continent

The alien freshwater mussel Sinanodonta woodiana (Lea, 1834) has rapidly spread throughout Europe over the past decades. This species can cope with a broad range of environmental conditions and has a high reproductive capacity making S. woodiana a successful invader. Due to its negative effects on native freshwater mollusk communities and parasitized fish it is critical to identify suitable habitats where S. woodiana may persist and how these habitats may be altered under future climate projections. We applied multivariate ordination methods to analyze the space-time relationship and a maximum entropy approach (MaxEnt) to predict the recent (1970–2000) and future (2041–2060 and 2081–2100) distribution of S. woodiana using environmental and climate variables for the European continent. After first sightings in 1979 there were only a few new locations and findings which increased unevenly and exponentially to a maximum of about 100 new locations per year followed by decline during the last few years. Under recent climate condition, 2.3% of European watersheds are predicted as highly suitable habitat for S. woodiana and located in the temperate climate zone between 40°N and 60°N. Suitable habitat was associated with lowland watersheds characterized by fluviatile deposits and agriculture. Elevation, the distance between water bodies, land cover and mean temperature of the coldest quarter were the main factors influencing the modeling results. For future climate scenarios, highly suitable habitat increased to 2.4% by the middle of this century and decreased to 2.2% by the end of the century under the ‘least radiative forcing’ scenario. For the intermediate and high radiative forcing in 2050 and 2100, highly suitable habitat decreased to 2.2% and 1.7% and to 2.2% and 2.2%, respectively. Results from our study can be used as a baseline to better understand potential invasion pathways, identify high risk areas, and to initiate early detection and rapid response strategies.

Simultaneous species detection and discovery with environmental DNA metabarcoding: A freshwater mollusk case study.

Environmental DNA (eDNA) sampling is a powerful tool for rapidly characterizing biodiversity patterns for specious, cryptic taxa with incomplete taxonomies. One such group that are also of high conservation concern are North American freshwater gastropods. In particular, springsnails of the genus Pyrgulopsis (Family: Hydrobiidae) are prevalent throughout the western United States where >140 species have been described. Many of the described species are narrow endemics known from a single spring or locality, and it is believed that there are likely many additional species which have yet to be described. The distribution of these species across the landscape is of interest because habitat loss and degradation, climate change, groundwater mining, and pollution have resulted in springsnail imperilment rates as high as 92%. Determining distributions with conventional sampling methods is limited by the fact that these snails are often <5 mm in length with few distinguishing morphological characters, making them both difficult to detect and to identify. We developed an eDNA metabarcoding protocol that is both inexpensive and capable of rapid, accurate detection of all known Pyrgulopsis species. When compared with conventional collection techniques, our pipeline consistently resulted in detection at sites previously known to contain Pyrgulopsis springsnails and at a cost per site that is likely to be substantially less than the conventional sampling and individual barcoding that has been done historically. Additionally, because our method uses eDNA extracted from filtered water, it is non-destructive and suitable for the detection of endangered species where "no take" restrictions may be in effect. This effort represents both a tool which is immediately applicable to taxa of high conservation concern across western North America and a case study in the broader application of eDNA sampling for landscape assessments of cryptic taxa of conservation concern.

Integrated analysis of physiological, transcriptome, and metabolome analyses of the gills in Solenaia oleivora under ammonia exposure

Ammonia is a common toxicant in aquatic systems and one of the key factors affecting aquaculture. However, data on mollusks’ toxic response and coping mechanisms to ammonia nitrogen, especially freshwater mollusks, are still lacking. In this study, we evaluated the tolerance of a freshwater mollusk Solenaia oleivora to ammonia and investigated its coping mechanisms by combining physiological, metabolic, and transcriptomic analyses in the gills. The acute toxicity test revealed that the LC50–96 h (temperature-20 ℃, pH-7.4) of ammonia in S. oleivora was 63.29 mg/L. The physiological and TUNEL results showed that although 10 mg/L ammonia exposure increased the activities of antioxidant, immune and ammonia detoxification-related enzymes, it still caused oxidative damage and cell apoptosis of gill tissues. A total of 97 differential metabolites (DMs) and 3431 differential expressed genes (DEGs) were identified after ammonia stress. Among them, most DMs and DEGs were involved in immune response, antioxidant, cell apoptosis, carbohydrate metabolism, amino acid metabolism, and lipid metabolism. The enhancement of glycolysis and lipid metabolisms may provide energy for immune response and ammonia detoxification. In addition, glutamine synthesis, alanine synthesis and urea cycle were involved in ammonia nitrogen detoxification in the gill tissue of S. oleivora. Our results indicate that ammonia leads to individual death in S. oleivora, as wells as oxidative damage, cell apoptosis, immune response, and metabolic changes of gill tissues. The findings will provide valuable information to assess the potential ecological risk of environmental ammonia to freshwater mollusks and theoretical guidance for the healthy aquaculture of S. oleivora.

DISSECTING BIOCHEMICAL MECHANISMS THAT MEDIATE TOLERANCE TO MILITARY CHEMICAL STRESSORS IN DIVERSE MALACOLOGICAL SYSTEMS

The ongoing military conflict in Ukraine has severely contaminated freshwater ecosystems with heavy metal pollutants including lead from ammunition and explosives. This study investigates the physiological and biochemical mechanisms of resistance in the freshwater mollusks. This study examines how freshwater mollusks, specifically Planorbarius corneus and Viviparus viviparus, resist lead compounds. Lead pollution from military activities poses a significant threat to aquatic life due to its toxicity and bioaccumulation. The research investigated species-specific responses to lead exposure, revealing differences in adaptations. Both mollusk species showed increased levels of carotenoids and proteins when exposed to higher lead concentrations, indicating a compensatory response to oxidative stress. These findings enhance our understanding of adaptive mechanisms against lead toxicity in aquatic environments affected by military pollution.

An annotated type catalogue of the land and freshwater mollusks from Tunisia and Libya in the Natural History Museum “Giacomo Doria” of Genova (Italy)

In the present work are listed the type specimens of land and freshwater molluscs from Tunisia and Libya deposited in the Natural History Museum “Giacomo Doria” of Genova (Italy). The historical nucleus of the malacological collections of the Museum of Genova is made up of the material collected by the young Giacomo Doria. After the official creation of the Museum in 1867, the malacological collection increased considerably in number of species and importance also through the material collected in various scientific missions organized by the Museum around the world. After 1916, the director Raffaello Gestro reorganized all this material and began the cataloging and selection of the type species. Nineteen nominal species described by Arturo Issel, Laura Gambetta, Jole Bisacchi and Rolf Arthur Max Brandt have been traced in these malacological collections. The type series described (types and syntypes) but also the material coming from the description localities and collected by the author himself (sometimes referred to as “topotypes”) were examined. For each taxa, the collection data obtained from the labels, the current taxonomic classification, the photographic documentation, remarks and the malacological bibliography are provided.

Expansion of Sinotaia quadrata (Mollusca: Gastropoda: Architaenioglossa: Viviparidae) in two major rivers from Argentina.

Invasive non-native freshwater mollusks are a growing concern in South America, with 16 species already recorded in the region. Among them, Sinotaia quadrata has only been documented in Argentina, for the first time in the Punilla Valley, Córdoba (2009) and La Plata, Buenos Aires (since 2015). In this study, we report the presence of S. quadrata in two additional areas, the Río de la Plata River and a stream (unnamed) in the Paraná River basin, two of the most significant rivers in South America, located in the provinces of Buenos Aires and Entre Ríos, respectively. These new records confirm the invasive nature of this species, which has also been identified in Europe, the United States, and Africa in recent years. The findings of this study highlight the need for continued monitoring and management of invasive species in South America's freshwater ecosystems.

Proteomics and phosphoproteomics reveal novel proteins involved in Cipangopaludina chinensis carcasses.

Cipangopaludina chinensis is a common freshwater mollusk that is widely distributed worldwide, especially in China. In our research, 1,382 proteins and 1,039 phosphorylated proteins were identified from C. chinensis carcasses, and 690 differentially expressed proteins (DEPs) were quantified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that the DEPs are involved in cellular processes, single-organism processes, metabolic processes, developmental processes, localization, and biological regulation. The phosphorylated proteins were found to be related to the Rap1 signaling pathway, Ras signaling pathway, calcium signaling pathway, and longevity-regulating pathways. Moreover, we also identified important regulatory enzymes, such as guanylate cyclase, tyrosine protein kinase, receptor protein tyrosine kinase, and glyoxylate reductase/hydroxypyruvate reductase. Notably, we found guanylate cyclase to be present in multiple signaling pathways, including the Rap1 signaling pathway, calcium signaling pathway, Ras signaling pathway, insulin secretion, longevity regulating pathway, glutamatergic synapse, circadian entrainment, and gap junction. This enzyme may play a crucial role in regulating molecular mechanisms in C. chinensis. In summary, proteomic and phosphoproteomic analyses of C. chinensis carcasses displayed significant differences among different geographical isolates, which helps enhance our understanding of food nutrition, signaling pathways, and metabolic mechanisms in C. chinensis.

Uso de ferramenta geoespacial para predição da distribuição de Melanoides tuberculata (Müller, 1774) e alguns gastrópodes límnicos nativos encontrados no Brasil

Abstract: One of the most common environmental impacts that has caused irreversible effects on ecosystems is the introduction of exotic species. In addition to the ecological disasters that can be caused, such as the decline and extinction of native species, this phenomenon can generate significant economic losses and the possibility of the spread of parasites that are transmitted by these exotic species. These processes can be accentuated by climate change, which over time alters the global distribution pattern of the affected species, generating cases of niche overlap with species that share similar niches. In this sense, the knowledge about the areas with possible occurrence these species can direct the monitoring and control measures. In this study, we developed current and future prediction models to identify areas of suitability in the Neotropics for Melanoides tuberculata (Müller, 1774) and nine species of mollusks native to the American continent using the ecological niche modeling tool. In addition, we evaluated the ecological niche overlap between the invasive species and the native species of freshwater mollusks to verify whether the effects of climate change would alter the distribution of these organisms. The following methodological procedures were adopted to prepare the forecasting models: records of occurrence of the mollusks in different databases and search of environmental data for climate conditions in current and future scenarios in WorldClim 2.0 (SSP2-4.5 and SSP2-8.5). Besides, modeling procedures using seven packages of R software, evaluation of the models using the true skill statistic (TSS) metric, construction of maps and quantification and overlapping of ecological niche of the species included in the analysis. The results indicated that several areas of the Neotropics are suitable for the occurrence of M. tuberculata in the current scenarios. Moreover, the suitable areas for its occurrence will probably be expanded in both future scenarios. For native species, there were significant differences in relation to the areas of suitability, with a reduction for some species. Niche similarity tests indicated significant overlap only between M. tuberculata and the planorbid Biomphalaria straminea (Dunker, 1848). We discuss that the expansion of M. tuberculata can have negative consequences, including the reduction of native gastropod species and the spread of trematodes of medical and veterinary importance that this mollusk can transmit.

Identification of prevalence and degree of infection of paramphistomatosis of cattle according to the age: Case of districts of the Republic of Karakalpakstan

According to our research, the ecological situation in Karakalpakstan has gotten worse recently. This includes the Aral Sea tragedy, the drying up of many lakes due to droughts, the loss of most of the natural gastrotilax foci, as well as other paramphistomata like P.ichikawae and rare cases of L.scotiae. The purpose of this study was to assess the prevalence of paramphistomatosis in cattle across different districts of the Republic of Karakalpakstan and to evaluate the infection's impact based on the animals' age. Research was conducted in the districts of Tortkul, Amudarya, Ellikkala, and Beruni. Methods included helmintoovoscopic examination of dung samples from 478 cattle and comprehensive helminthological dissection of 40 cattle. Results indicated an average infection rate of 3.9%, with the highest prevalence in Amudarya district (5.5%) and the lowest in Tortkul district (3.3%). Age-wise, infection rates were 3.5% in calves (6-12 months), 3.7% in young cattle (1-2 years), and 2.5% in older cattle (2 years and older). The study concluded that paramphistomatosis is a significant issue in Karakalpakstan, with notable age and regional variations. The Amudarya district, with more natural freshwater mollusc biotopes, exhibited a higher prevalence, suggesting a correlation between mollusc populations and infection rates.

The non-indigenous freshwater molluscs of Lake Monterosi (Latium, central Italy)

The non-indigenous freshwater molluscs of Lake Monterosi (Latium, central Italy)

Mehkužci (polži in školjke) zgornjega toka Neretve

During a survey taking place from 29.6.2022–2.7.2022 in Bosnia and Herzegovina in the river-floodplain system of the upper Neretva River around Ulog, 51 species of molluscs were found at 12 sampling sites. Besides manual sampling in the water bodies, the main sampling technique consisted of sieving of river deposits, to maximise the coverage of species diversity. The majority of the species were terrestrial gastropods (45 out of 51), most of them common species of forests and moist areas, but also of grassland. In the Neretva River itself and in adjacent waterbodies, six species of freshwater molluscs were found. Among them, at least three species of spring snails of the taxonomically challenging genera Belgrandiella, Bythinella, and Paladilhiopsis were found, the latter one only in river deposits. Future research should focus on truncatelloidean snails in the groundwater system of the upper course of the Neretva River. Furthermore, a broader investigation of the mollusc fauna of Bosnia and Herzegovina would help to clarify taxonomically unresolved questions of species of the Balkan region and possibly reveal species new for science.

Achatina fulica infected by Angiostrongylus cantonensis in Manaus, brazilian amazon region, and the risk of transmission of eosinophilic meningitis

Angiostrongylus cantonensis, which causes the zoonosis Eosinophilic Meningitis (EM), has become increasingly widespread in Brazil. Terrestrial mollusks, especially the exotic giant African snail Achatina fulica, have being found naturally infected with this nematode besides some few freshwater species. In this study, we collected several terrestrial and one freshwater mollusks from five different localities in the city of Manaus, in the Brazilian Amazon Region. One hundred and eighteen specimens from nine different species were obtained. In all, 49 specimens were analyzed parasitologically, including A. fulica (42 specimens), Bulimulus sp. (one specimen) and the freshwater species Pomacea dolioides (five specimens). The other specimens died or were represented by shells. Specimens of A. fulica from one locality were found naturally infected with A. cantonensis, which was confirmed by phylogenetic analysis of mitochondrial MT-CO1 gene sequences. A recent case of EM reported in the Amazon region, in the city of Macapá, reinforces the need of effective surveillance of areas in which the parasite is known to occur, as well as raising the awareness of local populations at risk of infection. We highlight both the role of A. fulica in the transmission of A. cantonensis and the need for effective measures to control the spreading of EM in Brazil. KEY WORDS: Mollusk; neural angiostrongyliasis; neurotropic parasite; intermediate host

The Early Pleistocene freshwater mollusks of the Denizli Basin (Turkey): a new long-lived lake fauna at the crossroads of Pontocaspian and Aegean-Anatolian realms

We describe here a newly discovered, diverse fossil fauna of freshwater gastropods and bivalves from the Denizli Basin in SW Turkey. The material was collected from the Kolankaya Formation, for which latest chronostratigraphic and magnetostratigraphic data indicate an Early Pleistocene age, which is much younger than previously assumed for the fossil-bearing strata of the Denizli Basin. The fauna consists of at least 27 species (25 gastropods, 2 bivalves) and includes a new genus,Harzhauseriagen. nov., and 6 new species within the Hydrobiidae: Falsipyrgula ? coronatasp. nov., Graecoanatolica ? alcicekorumsp. nov.,Harzhauseria schizopleuragen. et sp. nov.,Iraklimelania minutissimasp. nov.,Iraklimelania submediocarinatasp. nov., and Xestopyrguloides ? sagittasp. nov.Additionally, we define lectotypes forStaja orientalis(Bukowski, 1896) andValvata orientalisFischer, 1866, as well as a neotype forTheodoxus percarinatus(Oppenheim, 1919). Nine of the recovered species (33.3%) are only known from the Denizli Basin. Almost half of the fauna (44.7%) is endemic to the Aegean–Anatolian region, with biogeographical affinities to the Pliocene–Early Pleistocene faunas of Rhodes, Kos, and mainland Greece, as well as the Çameli and Eşen Basin in Turkey. On the genus level, the fauna also contains several typical Pontocaspian elements. The composition points toward a typical long-lived lake environment with oligohaline conditions.

Continental mollusks from the Olmos Formation (Upper Cretaceous), Coahuila, Mexico

We describe freshwater mollusks from the Olmos Formation, Campanian, Upper Cretaceous. The results were obtained from several specimens of mollusks, identified with two families of gastropods: Viviparidae (Viviparus sp.) and Physidae (Mesolanistes sp.), and three families of bivalves: Limidae (Pseudolimea sp.), Unionidae (Proparreysia sp., Unio sp., Unionelloides? sp., Plesielliptio sp., and Ostreidae (Ostrea sp.). Based on this taxonomic recognition, along with the associated fossil flora, it was possible to get a preliminary of the environment where the mollusks lived. The interpretation of the paleoenvironment resemble freshwater bodies adjacent to an estuarine system. Furthermore, the mixing of specimens of brackish and freshwater environments is indicative of a transport of some of these mollusks. The general view of the paleoenvironment where the mollusks inhabited is that of a transitional freshwater-estuarine in the Olmos Formation during Campanian times.

Scientific and educational potential of the malacological collection of the State Museum of Natural History of the National Academy of Sciences of Ukraine

The importance of the malacological collection of the State Museum of Natural History of the National Academy of Sciences of Ukraine in Lviv for the history and further development of malacological research in Ukraine is considered. The scientific potential of stock malacological materials, accumulated in the museum since the second half of the 19th century and significantly supplemented during the last decades, was analyzed in temporal and geographical aspects, as well as taking into account the taxonomic diversity and intraspecific conchological variability of the molluscs of Ukraine, the presence of typical materials, etc. It was found that the main (scientific) part of the malacological collection well represents the present land and freshwater mollusc fauna of Ukraine and its western part. Not represented in the museum's malacological collection are still some species that are mainly locally distributed in Ukraine and often have small sizes, which further complicates their sampling. Among the more recent additions to the malacological collection, we can especially mention the samples related to the study of the land mollusc fauna of the steppe zone of Ukraine, which remained poorly studied until the end of the 20th and even the beginning of the 21st century, as well as to the shell color and banding polymorphism in the Eastern European populations of two introduced species, Cepaea nemoralis and C. hortensis. Among the auxiliary part of the malacological collection, a large block of materials that can be used for exhibition purposes is selected. They allow demonstrating a wide range of topics from the taxonomic and morphological diversity of molluscs of Ukraine and the world to conchological adaptations. It can be useful when studying corresponding sections of a school biology course, as well as for students of biological specialties, amateur naturalists, etc. Various forms of virtual exhibiting allow to shown the public also numerous materials of the main (scientific) part of the malacological collection, which became possible within the framework of the Educational online program “Molluscs”. This allows us to talk about the gradual transformation of the main part of the malacological collection from a classical scientific collection to a scientific and educational one with virtual access.

Comparative phenomics: a new approach to study heterochrony.

Understanding the links between development and evolution is one of the major challenges of biology. 'Heterochronies', evolutionary alterations in the timings of development are posited as a key mechanism of evolutionary change, but their quantification requires gross simplification of organismal development. Consequently, how changes in event timings influence development more broadly is poorly understood. Here, we measure organismal development as spectra of energy in pixel values of video, creating high-dimensional landscapes integrating development of all visible form and function. This approach we termed 'Energy proxy traits' (EPTs) is applied alongside previously identified heterochronies in three freshwater pulmonate molluscs (Lymnaea stagnalis, Radix balthica and Physella acuta). EPTs were calculated from time-lapse video of embryonic development to construct a continuous functional time series. High-dimensional transitions in phenotype aligned with major sequence heterochronies between species. Furthermore, differences in event timings between conspecifics were associated with changes in high-dimensional phenotypic space. We reveal EPTs as a powerful approach to considering the evolutionary importance of alterations to developmental event timings. Reimagining the phenotype as energy spectra enabled continuous quantification of developmental changes in high-dimensional phenotypic space, rather than measurement of timings of discrete events. This approach has the possibility to transform how we study heterochrony and development more generally.

Some Components of the Serotonergic System in the Eyes of Two Species of Freshwater Molluscs

Some Components of the Serotonergic System in the Eyes of Two Species of Freshwater Molluscs

SOME COMPONENTS OF THE SEROTONERGIC SYSTEM IN THE EYES OF TWO SPECIES OF FRESHWATER MOLLUSCS

Labeling of 5-HT-immunoreactive structures was performed on eye slices of freshwater molluscs Lymnaea stagnalis and Pomacea canaliculata. In the periocular region of both species an increased density of 5-HTergic fibers forming structurally distinct plexuses and partially penetrating into the retina was detected. Transcription of serotonin receptor genes was detected in eye tissues: two types in L. stagnalis and three in P. canaliculata. Its relative level is significantly upregulated compared with central ganglia of the nervous system and tentacles. Additionally transcription of the 5HT transporter gene was recorded in P. canaliculata tissues.The obtained results are discussed in terms of a possible serotonergic mechanism of modulation of processes in the retina of gastropods.

Updated systematic inventory of the non-marine (land &amp; freshwater) molluscs occurring in the tropical mainland territory of the Guaianas (British, Dutch/ Surinam &amp; French), Northern region of South America located between Venezuela and Brazil

Introduction: Simultaneous with the malacological studies carried about the country of Venezuela (Agudo-Padrón 2023 a-b) and their immediate insular neighbor territories of Trinidad &amp; Tobago (Agudo-Padrón 2023 c) &amp; the Dutch ABC (Agudo-Padrón 2023 d), additionally since 2014 the “Projeto AM” (Brazil) has carried parallel out taxonomic, bioecological and conservation research of the non-marine (land &amp; freshwater) molluscs present in the mainland territory of the three (3) “Guianas” – including the “English/ British Guiana” (territory historically disputed, actively to this day, by “Venezuela”), the “Dutch Guiana” (better known as "Surinam"), and the “French Guiana” (border with the extreme North of “Brazil”). To date, these aspects of the natural history of this geographic region, located in the Northern sector of South America, have been regularly studied. Objective: Substantial updating of this knowledge through an exhaustive review of the regional malacological literature of historical and recent nature available. Methodology: Between 2014 and the present, a sequential review of the species occasionally referred to in the regional literature was carried out, examined from the perspective of the current taxonomy in force. Results and conclusions: Verification and determination of hundred one (101) referred taxons, including 63 land/ terrestrial (2 subspecies &amp; 61 species) and 38 aquatic (limnic/ freshwater) forms/ species (31 gastropods &amp; 7 bivalves), taxonomically grouped into twenty-seven (27) families and forty-four (44) genera.

Trace Element Patterns in Shells of Mussels (Bivalvia) Allow to Distinguish between Fresh- and Brackish-Water Coastal Environments of the Subarctic and Boreal Zone

The accumulation of trace metals in the shells of bivalves allows quantitative assessments of environmental pollution and helps to reconstruct paleo aquatic environments. However, the understanding on how marine and freshwater mollusks control the level of trace elements in their shells remains very limited. Here, we compared the trace element composition of marine and freshwater bivalves from boreal and subarctic habitats, using examples of widely distributed species of marine (Mytilus edulis, M. trossulus) and freshwater (Anodonta anatina, Unio sp., Beringiana beringiana) mussels. Sizable differences in several trace element concentrations were detected between different species, depending on their environmental niches. A multiparametric statistical treatment of the shell’s elemental composition allowed to distinguish the impact of external factors (water and sediment chemical composition) from active metabolic (biological) control. In particular, the obtained results demonstrated that Ba:Ca and Pb:Ca ratios in mussels’ shells are closely related to the primary productivity of aquatic ecosystems. The Mn:Ca ratio allowed to constrain the environmental conditions of mussels’ species depending on the trophic state of inhabited waterbody. Overall, the marine mussels exhibited stronger biological control of trace element accumulation, whereas trace element pattern in shells of freshwater mussels was chiefly controlled by environmental factors. The obtained results might help to use the trace element composition of bivalves in distinguishing marine and freshwater habitats of mollusks in paleo environments.