Invasive New and Old World freshwater species in isolated springs of the Atacama Desert: implications for native species

Invasive species can significantly alter invaded ecosystems. In this study, we report the presence of two invasive species, the poeciliid fish Poecilia reticulata and the gastropod Melanoides tuberculata, in three isolated springs from the coast of the Atacama Desert in Antofagasta city, northern Chile. Both species were identified through diagnostic morphological features and phylogenetic analysis. This is the first confirmed record of P. reticulata in natural ecosystems of Chile. The finding of M. tuberculata represents the first record of the species in the Antofagasta Region, and the third in the country. Considering the well-documented adverse effects of both species on invaded ecosystems and their high potential for spread, we recommend the prompt implementation of mitigation measures. These should focus on the direct mechanical removal of these species, given the relatively straightforward sampling process and the relatively small size of the springs. Such measures would significantly contribute to the preservation of native species, particularly those categorized as vulnerable.