Evaluation of past and present suitable environments for Culex coronator (Diptera: Culicidae)

Culex coronator is a Neotropical mosquito species first recorded in Trinidad and Tobago in 1906 and is a competent vector for multiple medically important pathogens. The geographic distribution of Cx. coronator remained primarily limited to South and Central America, Texas and New Mexico before expanding into Louisiana in 2004 and subsequently establishing east along the Gulf Coast and then northward across 14 states. We used a species distribution modeling approach to estimate abiotic environmental suitability across parts of the Americas before and after its geographic range expansion in 2004. Georeferenced occurrence records were gathered from the Global Biodiversity Information Facility, and scientific literature. Bioclimatic variables were obtained from the TerraClim dataset, which derives variables from monthly temperature and precipitation to generate both monthly and annual climate metrics. Both occurrence and environmental data were grouped into two periods, 1958-1989 and 2000-2023 to represent Cx. coronator’s distribution prior to and subsequent to the geographic expansion in 2004. Models were run using a maximum entropy algorithm in Maxent. Variables that contributed the greatest to model performance included measures of annual mean temperature and precipitation. Model projections indicated an increase in suitable habitats for Cx. coronator throughout much of the Gulf Coast and farther north along the coastline during the 2000-2023, compared to the 1958-1989 period. Additionally, suitable habitats were projected in northwestern regions, suggesting potential for continued range expansion. Continued surveillance is essential to detect and mitigate the spread of this vector.