Two culicivorous mosquitoes, Toxorhynchites christophi and Lutzia vorax (Diptera: Culicidae), differentially shape mosquito larval communities within aquatic containers in a Korean temperate forest.

Container aquatic habitats such as tree-holes in temperate forests host diverse mosquito assemblages, yet the ecological functions of their obligate larval predators remain underexplored. We assessed the ecological roles of two widespread predatory mosquito larvae in Korea, Toxorhynchites christophi (Portschinsky) and Lutzia vorax Edwards, which share the same temperate forest container habitats. This study combined a 2-yr field mesocosm experiment (2023-2024) conducted in Gwangneung Forest in the central Korean Peninsula with laboratory analyses of the predatory behavior of the 2 species. Our field experiments revealed that the predation effects of the two species on mosquito larval communities were contrasting: Communities with Lt. vorax showed markedly low mosquito diversity and density, whereas those with Tx. christophi exhibited high diversity and evenness but low dominance. The two predators also showed temporal niche partitioning and different occurrence densities per container. In the laboratory experiment, both species displayed type II functional responses. However, Lt. vorax had a higher attack rate and a shorter handling time than Tx. christophi, yielding a greater theoretical maximum consumption. Only Lt. vorax showed significant preferences in tests using three dominant prey-mosquito species: Aedes koreicus (Edwards), Ae. flavopictus (Yamada), and Tripteroides bambusa (Yamada). Collectively, we propose that Tx. christophi and Lt. vorax each act as key predators that drive mosquito larval communities in opposite directions: Tx. christophi promotes greater diversity and evenness as a keystone predator, occurring at lower densities, whereas Lt. vorax collapses community structure through intense and rapid predation with higher densities per container.