Limnoperna fortunei, an Asiatic rivers bivalve has become a worldwide problematic invasive species causing several water quality and macrofouling problems. In the Neotropical region it was first recorded in 1991 in the Río de la Plata coast, Buenos Aires province. Since this, it showed a quick upstream invasion into the principals aquatic systems of the Plata Basin. Nevertheless, there is not a study about its invasion and distribution process in aquatic systems of Uruguay. We describe the new records of Limnoperna fortunei in Uruguayan coast of Río de la Plata, Santa Lucía, Negro and Uruguay Rivers. With these results we aim to estimate its distributional limits for Uruguay main hydrographical basins. We also deal with the role of salinity as the main abiotic factor in limiting the east distribution of this mussel in Uruguayan coast of Río de la Plata and as a potential determinant of the "new" colonization on the Atlantic and the Merín Lagoon Basins. Its presence in the ecosystems not only can cause changes at the ecosystem level but also endanger the associated community, favoring the displacement and the disappearance of endemic species.

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The invasive Asian golden mussel Limnoperna fortunei is continuously expanding through South America, altering aquatic ecosystem structure and functioning. While several native fish species predate on this mussel, these interactions, and their consequences for the food web, have not been studied in depth. We combine a survey of the fish assemblage trophic structure using gut contents and stable isotope analysis with an in situ exclusion experiment in order to: (a) determine the main fish species predating on L. fortunei; (b) estimate the contribution of L. fortunei to the biomass of fish assemblage; and (c) evaluate the role of fish on the density and maximum shell length of L. fortunei in the lower Uruguay River (the Río de La Plata Basin). We found that about one third of fish species in the assemblage (28 out of 81 species) consumed L. fortunei, which was an important food item (>10% of the dietary volume and >30% of frequency of occurrence) for 11 fish species. Stable isotope mixing models consistently suggested that >14% of the total biomass of the fish assemblage was derived directly from carbon derived from L. fortunei tissues. In addition, the exclusion experiment demonstrated that fish predation reduces the mussel density by c. 70% and the mussel maximum shell length by c. 40%. Synthesis and applications. Our research suggests a top‐down effect of fish on the invasive Asian golden mussel's abundance. This work highlights the need to preserve the native fish communities, particularly in South America, where many vulnerable migratory fish are of key relevance as Limnoperna fortunei consumers. In the light of these findings, actions such as implementing efficient fish passage technologies in the actual (and projected) dams of the Uruguay River basin and elsewhere become essential to avoid local extinctions of these natural invasion controls upstream of the dams.

Resumen: Los invertebrados (por ejemplo, cirripedios y mejillones) son los principales responsables de las pérdidas económicas a nivel industrial y naval de la bioincrustación, agravada por la colonización de especies invasoras (por ejemplo, el mejillón dorado, Limnoperna fortunei). Se han utilizado diversas estrategias para controlar la bioincrustación. Sin embargo, no son eficientes o causan una alta mortalidad de organismos acuáticos, incluso las tintas antiincrustantes. Actualmente, con la necesidad de preservar la salud humana y ambiental, se han enfocado en la investigación de nuevos agentes naturales para reemplazar las moléculas sintéticas tóxicas de estas pinturas. El estudio de productos naturales bioactivos a partir de plantas terrestres ha sido una opción prometedora en el campo clínico y puede tener el mismo potencial en el acuático. Así, la principal pregunta de este estudio es: ¿Cómo seleccionar los extractos y compuestos más prometedores? Este trabajo analizó artículos publicados sobre el tema con el objetivo de resaltar la información necesaria para centrar las investigaciones en antiincrustantes derivados de plantas terrestres. Se examinaron 29 artículos entre 1990 y 2020. Los productos naturales derivados de plantas terrestres tienen un gran potencial como antiincrustantes sostenibles, inhibiendo la colonización de micro y macrofouling. Los compuestos alcaloides y flavonoides de las familias Zingiberaceae, Myrtaceae y Fagaceae ya han mostrado resultados prometedores contra mejillones.