1 Department of Biology, Faculty of Sciences, Badji Mokhtar University, Annaba 23000, Algeria.
2 Laboratory of Biology, Water and Environment (LBEE), The 8 Mai 1945 University, Street P.O. Box 401, Guelma 24000, Algeria.
3 Biology Department, Concordia University, 7141 Sherbrooke St. W., Montreal, QC H4B 1R6, Canada.

Mosquito community composition can differ spatially and temporally within the same wetlands. Understanding this spatiotemporal variation is crucial, particularly in wetlands of conservation importance. Here, we examine the diversity and community composition of Culicidae (Diptera) across four sites within Fetzara Lake, a large Ramsar site in Northeast Algeria. For two years, we conducted monthly field surveys across four sites (Northeast, Northwest, Southeast, and Southwest) from April 2021 to March 2023. During these surveys, we used ovitraps to sample mosquitoes and assess species richness as well as alpha and beta diversity. We identified seven mosquito species (Aedes aegypti, Ae. albopictus, Ae. geniculatus, An. labranchiae, Culex perexiguus, Cx. pipiens, and Cs. longiareolata). There was a clear dominance of Culex pipiens (Usutu and West Nile virus vector), which accounted for 74.3% of all samples, whereas Aedes aegypti was the least abundant (<1%). Species richness varied between five and six across sites. The Shannon index and beta diversity revealed significant variation in species diversity across sites and seasons, likely driven by local differences in environmental conditions. This study emphasizes the importance of local variation in environmental conditions in shaping ecological communities in space and time.