Shifting mosquito diversity across urban environments in Córdoba City, Argentina.

Urbanization alters habitat structure and resource availability, with cascading effects on biodiversity and species composition. Mosquitoes, as adaptable organisms and major disease vectors, typically thrive in urban environments; however, comprehensive assessments along urban gradients remain scarce in South American cities. The aim of this study was to evaluate the influence of different urban environments on adult mosquito diversity and to assess their potential relationship with the risk of mosquito-borne diseases, such as dengue and encephalitis, within the urban ecosystem of Córdoba City, Argentina. Adult mosquitoes were collected during six samplings between April 2021 and February 2022 through CO₂‑baited light traps, spanning diverse urbanization levels and environmental conditions. The resulting dataset provided insights into how urbanization influences mosquito community structure and species distribution. A total of 4,821 individuals of 14 species were collected, with Culex quinquefasciatus (71.7%) and Aedes aegypti (9.9%) being the dominant species and recorded mainly at high urbanized areas. Species richness increased with distance from the city center, ranging from 5 or fewer species in highly urbanized areas to more than 12 species in peripheral areas with abundant trees. Multivariate analyses revealed three distinct environmental groups: central sites exhibited reduced vector species diversity dominated by a few taxa, whereas peripheral areas supported greater community richness. Seasonal patterns highlighted the absence of Ae. aegypti during winter, in contrast to the persistence of Culex species. By encompassing 30 systematically sampled sites across Córdoba, our study provides the first city‑wide assessment of mosquito community variation along an urbanization gradient, demonstrating that urban expansion reduces overall diversity while promoting competent vector species, thereby potentially heightening public health risks and underscoring the need for strengthened surveillance and control strategies in the context of ongoing urban growth and climate change.