The introduction of invasive species has become an increasing environmental problem in freshwater ecosystems due to the high economic and ecological impacts it has generated. This systematic review covers publications from 2010 to 2020, focusing on non-native invasive freshwater bivalves, a particularly relevant and widespread introduced taxonomic group in fresh waters. We collected information on the most studied species, the main objectives of the studies, their geographical location, study duration, and type of research. Furthermore, we focused on assessing the levels of ecological evidence presented, the type of interactions of non-native bivalves with other organisms and the classification of their impacts. A total of 397 publications were retrieved. The studies addressed a total of 17 species of non-native freshwater bivalves; however, most publications focused on the species Corbicula fluminea and Dreissena polymorpha, which are recognised for their widespread distribution and extensive negative impacts. Many other non-native invasive bivalve species have been poorly studied. A high geographical bias was also present, with a considerable lack of studies in developing countries. The most frequent studies had shorter temporal periods, smaller spatial extents, and more observational data, were field-based, and usually evaluated possible ecological impacts at the individual and population levels. There were 94 publications documenting discernible impacts according to the Environmental Impact Classification for Alien Taxa (EICAT). However, 41 of these publications did not provide sufficient data to determine an impact. The most common effects of invasive bivalves on ecosystems were structural alterations, and chemical and physical changes, which are anticipated due to their role as ecosystem engineers. Despite a considerable number of studies in the field and advances in our understanding of some species over the past decade, long-term data and large-scale studies are still needed to understand better the impacts, particularly at the community and ecosystem levels and in less-studied geographic regions. The widespread distribution of several non-native freshwater bivalves, their ongoing introductions, and high ecological and economic impacts demand continued research. Systematic reviews such as this are essential for identifying knowledge gaps and guiding future research to enable a more complete understanding of the ecological implications of invasive bivalves, and the development of effective management strategies.

Limnoperna fortunei, the golden mussel, is a bivalve mollusk considered an invader in South America. This species is responsible for ecological and economic damages due to its voluminous fouling capability. Chemical biocides such as MXD-100™ and sodium dichloroisocyanurate (NaDCC) are often used to control L. fortunei infestations in hydraulic systems. Thus, we proposed to investigate the effects of different periods (24, 48 and 72 h) of exposure to MXD-100™ (0.56 mg L-1) and NaDCC (1.5 mg L-1) on the gills of L. fortunei through morphological and molecular analyses. NaDCC promoted progressive morphological changes during the analyzed periods and only an upregulation of SOD and HSP70 expression during the first 24 h of exposure. MXD-100™ led to severe morphological changes from the first period of exposure, in addition to an upregulation of SOD, CAT, HSP70 and CYP expression during the first 24 h. In contrast, MXD-100™ led to a downregulation of CAT transcription between 24 and 48 h. In static conditions, NaDCC causes lethal damage after 72 h of exposure, and that exposure needs to be continuous to achieve the control of the species. Meanwhile, the MXD-100™ treatment presented several effects during the first 24 h, showing acute toxicity in a shorter period of time.

Environmental DNA (eDNA) has increasingly been used to detect rare species (e.g., newly introduced nonindigenous species) in both terrestrial and aquatic ecosystems, often with distinct advantages over traditional methods. However, whether water eDNA signals can be used to inform invasion risks remains debatable owing to inherent uncertainties associated with the methods used and the varying conditions among study systems. Here, we sampled eDNA from canals of the central route of the South-to-North Water Diversion Project (hereafter SNWDP) in China to investigate eDNA distribution and efficacy to inform invasion risks in a unique lotic system. We first conducted a total of 16 monthly surveys in this system (two sites in the source reservoir and four sites in the main canal) to test if eDNA could be applied to detect an invasive, biofouling bivalve, the golden mussel Limnoperna fortunei. Second, we initiated a one-time survey in a sub-canal of the SNWDP using refined sampling (12 sites in ~22 km canal) and considered a few environmental predictors. We found that detection of target eDNA in the main canal was achieved up to 1100 km from the putative source population but was restricted to the warmer months (May-November). Detection probability exhibited a significant positive relationship with average daily minimum air temperature and with water temperature, consistent with the expected spawning season. eDNA concentration in the main canal generally fluctuated across months and sites and was generally higher in warmer months. Golden mussel eDNA concentration in the sub-canal decreased significantly with distance from the source and with increasing water temperature and became almost undetectable at ~22 km distance. Given the enormity of the SNWDP, golden mussels may eventually expand their distribution in the main canal, with established \"bridgehead\" populations facilitating further spread. Our findings suggest an elevated invasion risk of golden mussels in the SNWDP in warm months, highlighting the critical period for spread and, possibly, management.
环境DNA(eDNA)已被越来越多地用于检测陆地和水生生态系统中的稀有物种(例如:新引入的外源物种)，相较于传统方法，其通常表现出明显优势。然而，由于所用方法固有的不确定性和不同研究系统的差异，水体eDNA信号是否可用于揭示入侵风险仍有争议。本研究中，我们从中国南水北调中线工程(以下简称南水北调工程)的渠道中提取eDNA样本，研究eDNA在这样一个独特的动水系统中的分布及其揭示入侵风险的效果。首先，我们在这一系统中进行了16次月度调查(涵盖源水库2个站点和干渠4个站点)，以测试eDNA是否可以用于检测入侵生物沼蛤Limnoperna fortunei，一种生物污损双壳贝类。其次，我们在干渠的一个支渠中，采用更加精细的取样方法(在约22公里的渠道中设置12个样点)，开展了一次考察多个环境因子的调查。我们发现，在距离假定源种群1100公里的干渠中可以检测到目标eDNA，但仅限于温暖的月份(5-11月)。目标eDNA的检出概率与日平均最低气温和水温呈显著正相关，这与预期的产卵季节一致。在支渠中，沼蛤eDNA浓度随着与源头的距离增加和水温的升高而明显下降，在约22公里处变得几乎无法检出。鉴于南水北调工程的巨大规模，沼蛤最终可能无法避免地扩张其在干渠的分布，已定殖的 “桥头堡 “种群会促进其进一步传播。我们的研究揭示了南水北调工程在温暖月份中升高的沼蛤入侵风险，凸显了其扩散和潜在管理的关键窗口期。.

Nanoparticles such as zinc oxide nanoparticles (ZnO-NP) that are incorporated in consumer and industrial products have caused concern about their potential ecotoxicological impact when released into the environment. Bivalve mollusks are susceptible targets for nanoparticle toxicity since nanomaterials can enter the cells by endocytosis mechanisms. The aim of this study was to evaluate the influence of ZnO-NP on the redox metabolism in Limnoperna fortunei and the DNA damage after exposure to ZnO-NP. Adult bivalves were incubated with 1-, 10-, and 50-μg mL-1 ZnO-NP for 2, 4, and 24 h. Ionic Zn release, enzymatic and non-enzymatic antioxidant activity, oxidative damage, and DNA damage were evaluated. Oxidative damage to proteins and lipids were observed after 4-h exposure and returned to baseline levels after 24 h. Superoxide dismutase levels decreased after 4-h exposure and increased after 24 h. No significant alteration was observed in the catalase activity or even DNA double-strand cleavage. The dissociation of ZnO may occur after 24 h, releasing ionic zinc (Zn2+) by hydrolysis, which was confirmed by the increase in the ionic Zn concentration following 24-h exposure. In conclusion, ZnO-NP were able to induce oxidative stress in exposed golden mussels. The golden mussel can modulate its own antioxidant defenses in response to oxidative stress and seems to be able to hydrolyze the nanoparticles and consequently, release Zn2+ into the cellular compartment.

Biofouling by the invasive golden mussel Limnoperna fortunei deleteriously affects artificial water systems, but few effective, environmentally friendly antifouling strategies exist. We propose ultrasound for control of this invasive mussel and report minimum exposure times to kill juveniles and adults at ultrasonic powers ranging 300-600 W from a fixed distance of 8.5 cm. Analysis using a PMA + RT-qPCR assay revealed the formation of tissue lesions in response to ultrasound, with gill tissue more prone to injury than adductor muscle tissue. Shell microstructure determined using scanning electron microscopy (SEM) + energy dispersive X-ray spectroscopy (EDS) is plywood-like, with a thicker shell and increased numbers of prism and nacre layers in adult mussels that provide greater resistance to ultrasound, reducing mortality and tissue lesions. Our results suggest L. fortunei biomass could be effectively reduced by ultrasound, especially for early life-history stages without, or with only immature shells.

The success of Limnoperna fortunei as an invasive freshwater bivalve species is related to its physiological plasticity to endure changes in environmental conditions. The aim of this study was to investigate the physiological responses of L. fortunei after feeding on Microcystis aeruginosa grown at 26 °C (control) and 29 °C during 10 days. At the beginning, we measured biomass, fatty acids (FAs) composition on Cyanobacteria grown at both temperatures at different time intervals. Afterwards, mussels were fed with the thawed M. aeruginosa cells and their FA profile was measured after 15 days of feeding. M. aeruginosa exposed to 29 °C had the highest content of the FAs 18:2ω6 and cis-18:1ω9. The FA profile of the consumer L. fortunei fed with M. aeruginosa cultures grown at 29 °C was also significantly different to those fed with cultures grown at 26 °C, with a significant increased Eicosapentaenoic acid (EPA, 20:5ω3) and Arachidonic acid (ARA, 20:4ω6) concentrations. L. fortunei was already known to be physiologically adapted to live at 29 °C, but our results also shown a high biosynthesis of EPA and ARA (increase of 70 and 40% respectively, compared with 26 °C) and avoided the lipid peroxidation of both FAs. This increased EPA and ARA biosynthesis may be an important source of ω3 and ω6 polyunsaturated FAs (PUFAs) for higher trophic levels, such as the pelagic fishes or birds that mainly prey on these mussels. The transfer of the cyanobacterial response at higher temperature to higher trophic levels will influence the overall functioning of freshwater bodies.

The intensive use of glyphosate in industrial agriculture may lead to freshwater contamination, encouraging studies of its toxic effect on non-target aquatic organisms. Glyphosate-based commercial formulations contain adjuvants, making them even more toxic than the active ingredient (a.i.) itself. The golden mussel Limnoperna fortunei is a freshwater invasive species which has been found to increase glyphosate dissipation in water and to accelerate eutrophication. The aim of this study is to evaluate the capability of L. fortunei to reduce the concentration of glyphosate in two commercial formulations, Roundup Max® and Glifosato Atanor®. Results were compared with the decay of the a.i. alone and in presence of mussels. Evasive response and toxicity tests were performed in a first set of trials to analyze the response of L. fortunei exposed to Roundup Max® and Glifosato Atanor®. Subsequently, we conducted a 21-day degradation experiment in 2.6-L microcosms applying the following treatments: 6 mg L-1 of technical-grade glyphosate (G), Glifosato Atanor® (A), Roundup Max® (R), 20 mussels in dechlorinated tap water (M), and the combination of mussels and herbicide either in the technical-grade (MG) or formulated form (MA and MR) (all by triplicate). Samples were collected at days 0, 1, 7, 14 and 21. No significant differences in glyphosate decay were found between treatments with mussels (MG: 2.03 ± 0.40 mg L-1; MA: 1.60 ± 0.32 mg L-1; MR: 1.81 ± 0.21 mg L-1), between glyphosate as a.i. and the commercial formulations, and between the commercial formulations, suggesting that the adjuvants did not affect the degrading potential of L. fortunei. In addition to the acceleration of glyphosate dissipation in water, there was an increase in the concentration of dissolved nutrients in water (N-NH4+ and P-PO43-) even higher than that caused by the filtering activity of the mussels, probably resulting from stress or from the degradation of glyphosate and adjuvants. We believe that a larger bioavailability of these nutrients due to glyphosate metabolization mediated by mussels would accelerate eutrophication processes in natural water bodies. The approach used here, where L. fortunei was exposed to two commercial formulations actually used in agricultural practices, sheds light on the potential impact of glyphosate decay on water bodies invaded by this species.

In this study we test the sensitivity of three sizes of golden mussel (Limnoperna fortunei), an introduced species in Argentina, to a 96-h exposure to [Formula: see text], [Formula: see text], and [Formula: see text]. We also analysed the relative sensitivity of L. fortunei compared to other freshwater bivalve equivalent sensitivity data. The ANOVA results showed that both factors, heavy metal and size, had significant effects (p = 0.0013 and p = 0.0091, respectively) on the mortality of the golden mussel. Tukey\'s test showed significant differences for [Formula: see text] treatment and the smallest size class (7 mm [Formula: see text]). The relative sensitivity analysis showed that [Formula: see text] values for the smallest size class of L. fortunei exposed to [Formula: see text] and [Formula: see text] were in the low range, with values of 11.40 mg/L and 12.65 mg/L, respectively. In the case of [Formula: see text] (1.66 mg/L), its [Formula: see text] was in the medium-low range of the freshwater bivalve sensitivity distribution.

The Asian invasive species Limnoperna fortunei (Dunker, 1857), known as the golden mussel, causes great economic and environmental damage due to its fixative capacity and accelerated proliferation. Molecular studies for the control of larval and adult forms are of great economic, scientific and technological interest. Here, we first report on the compositional analysis of the L. fortunei proteome obtained through shotgun analysis using LC-MS/MS. Among those 2790 proteins identified, many of them related to secretory processes and membrane receptors. Our second approach consisted in exposing the mollusc to the molluscicide niclosamide to evaluate the induced proteomic alterations. Exposure to niclosamide at 0.25 mg/L for 24 h resulted in a pronounced differential abundance of proteins when compared to those obtained when exposure was reduced to 4 h at 2.3 mg/L. In total, 342 proteins were found differentially expressed in the responsive individuals as revealed by label-free quantitative proteomics. Regarding the affected cell processes were: cell division and differentiation, cytoskeletal organization and compartment acidification (upregulated), and energy metabolism (downregulated). Our findings constitute the first inventory of the expressed proteome of the golden mussel and have the potential to contribute with a more rational proposition of molecular targets for control and monitoring of this species. SIGNIFICANCE: With the recent availability of transcriptomic and genomic data applied to L. fortunei the timing is right to interrogate its putative gene repertoire using proteomic techniques. These have the potential to validate the existence of the predicted genes, infer their relative abundance and quantify their levels as a response to environmental stressors or various agents. Here we provided an inventory of the golden mussel proteome and evaluated its response to the molluscicide niclosamide. The obtained results open new avenues for intervention aimed at its control or elimination, particularly by targeting the various cellular processes that were uncovered.

The literature indicates that exotic species have a greater tolerance to environmental stressors compared with native species. In recent decades, the introduction of contaminants into the environment has increased as a result of industrialization. The objective of this study was to verify the resistance of bivalve mollusks from freshwater native (Anodontites trapesialis) and exotic (Limnoperna fortunei) species to chemical contamination using an ex vivo/in vitro approach. Gill and muscle tissues were exposed to two different types of environmental stressors, copper (metal), and Roundup Transorb® (herbicide). The tissues were submitted to a cytotoxicity test in which the lysosomal integrity was assessed, from the adaptation of a method to isolated cells, and multixenobiotic resistance (MXR) test which evaluated cellular defense. In the exotic species, only copper at 9000 μg/L and Roundup Transorb® at 5000 μg/L were cytotoxic. In the native species, copper cytotoxicity at 900 and 9000 μg/L and Roundup Transorb® at 50 and 5000 μg/L were observed. Results were the same in both tissues. The MXR, responsible for the extrusion of contaminants (cell defense), was inhibited in both species when exposed to the contaminants, this cell defense system seems to be more inhibited in the native species, when exposed to both pollutants, indicating greater sensitivity. Therefore, cytotoxicity may be related to the lack of capacity of cellular defense. In relation to lysosomal integrity, the native species was more sensitive to cytotoxic pollutants, where a greater number of experimental conditions of metals and herbicide showed cytotoxicity, as well as more experimental situations inhibited its ability to defend itself.