First record and range extension of Corbicula fluminea (Müller, 1774) (Bivalvia, Cyrenidae) in the Chapada dos Veadeiros region, Goiás, Brazil

Corbicula fluminea (Müller, 1774) is an Asian freshwater clam that is widely distributed throughout the world through multiple introductions. Its invasion can cause environmental and economic damage. In Brazil, C. fluminea is recorded in all major hydrographic basins. Here, we report the first record of C. fluminea in the Chapada dos Veadeiros region of Goiás, Brazil. This new record extends the known distribution of this species to a conserved area in the Cerrado biome, towards areas of interest for conservation and integral protection units of the biodiversity.

Homogenization of Macroinvertebrate Assemblages and Asiatic Clam Corbicula fluminea Invasion in a River of the Arid Patagonian Plateau, Argentina

The invasion of the Asiatic clam Corbicula fluminea in South America has already reached Patagonia. Despite the well-known direct and indirect impacts that this species exerts on fresh-water ecosystems, particularly on benthic communities, few studies have been undertaken on its effect on the composition and structure of aquatic macroinvertebrate assemblages. This study evaluated the effects of the invasion of the Asiatic clam C. fluminea on the aquatic macroinvertebrate assemblages of the Limay River, one of the most important rivers of the arid plateau of Argentinian Patagonia. As this river is currently in the process of being invaded, it was possible to compare invaded and non-invaded sites. Invaded sites displayed a certain homogenization of their constituent species and functional composition. Non-metric multidimensional scaling, similarity analysis and similarity percentages showed negative or positive influence of the presence of this species on the abundance of some taxa, due to competition for resources in this low-productivity Patagonian ecosystem. The deposition of the faeces and pseudo-faeces of C. fluminea enriches the organic content of the sediments. However, its pedal feeding can function as a competitive strategy: by consuming its own deposited organic matter when food is scarce, the amount available to other macroinvertebrates is reduced. This paper is the first contribution on the impact of this invasion on northern Patagonia’s aquatic macroinvertebrate assemblages.

Malacological news from the Czech and Slovak Republics in 2020

This paper presents important faunistic records including location data with all details conducted in the Czech and Slovak Republics during 2020. Four new non-native species, Arion intermedius, Ambigolimax valentianus, Clathrocaspia knipowitschii and Krynickillus melanocephalus, were recorded outdoors in Slovakia. Radix lagotis was genetically confirmed for the first time from several sites in the Czech Republic and Slovakia. Corbicula fluminea, recorded in Moravia for the first time in 2018, was found in another river, ca 50 km far from the first occurrence. Cepaea nemoralis, recorded in Slovakia for the first time in 2015, seems to have started spreading. New sites of Cornu aspersum were noticed in Prague and Bratislava; for the first time it was also found in Brno. There are also new records of several endangered species, e.g. Vertigo moulinsiana, Pisidium hibernicum, P. globulare, and Pseudanodonta complanata, presented.