Predation of Toxorhynchites splendens on Aedes larvae under laboratory conditions and insights into its ecological role as a regulator

Toxorhynchites larvae are obligate predators and considered as biological control agents against container-breeding Aedes mosquitoes. However, quantitative information on their life history traits, stage-dependent predation dynamics, and lifetime predation capacity remains limited. Here, we reported a Toxorhynchites splendens population collected from Foshan city, China, and provided an integrated assessment of its morphology, life history, and predatory performance against Aedes larvae under laboratory conditions. Field surveys revealed substantial overlap between Tx. splendens and Ae. albopictus larvae in the rural areas. Molecular and morphological analysis confirmed their species identity, though slight geographical morphological variation was observed. No significant differences were observed between males and females in egg hatching time or larval developmental duration. However, females had significantly longer pupal duration and adult lifespan, while males had greater pupal width and wing length. Functional response experiments demonstrated that Tx. splendens predation generally followed a Holling type II functional response, but stable model fitting was not observed for all predator–prey stage combinations, indicating pronounced stage-dependent heterogeneity in predation dynamics. By integrating daily prey consumption derived from stable functional response models with instar-specific developmental durations, we found that the estimated lifetime prey consumption of Tx. Splendens increased with initial prey density and was consistently higher for Ae. albopictus than for Ae. aegypti . Our results highlight the importance of developmental stage in shaping predation dynamics of Tx. splendens and provide quantitative insights into the predatory capacity of Tx. splendens under laboratory conditions and its potential contribution to future biological control strategies.