New Faunal Records of Mymaridae (Hymenoptera) Egg Parasitoids of Cicadellid Leafhoppers on Vegetable Crops

Abstract

Extensive faunistic surveys were conducted in vegetable-growing agroecosystems to document the diversity and distribution of mymarid egg parasitoids associated with cicadellid leafhoppers infesting economically important vegetable crops. Sampling was carried out across multiple production areas during different cropping seasons through collection of leafhopper-infested plant materials and laboratory rearing of parasitoids from host eggs. Adult parasitoids emerging from leafhopper eggs were examined using morphological and molecular techniques for accurate taxonomic identification. Diagnostic morphological characters including antennal segmentation, forewing shape, body sculpture, ovipositor structure, and mesosoma morphology confirmed the presence of several species belonging to the family Mymaridae, including multiple new regional faunal records. Molecular characterization using mitochondrial cytochrome oxidase I (COI) gene sequencing supported species identification and phylogenetic placement within recognized mymarid lineages. The recovered parasitoids were associated with leafhopper species attacking vegetable crops such as tomato, bean, eggplant, cucumber, and chili pepper. Seasonal abundance of parasitoids varied according to host population density, crop phenology, and environmental conditions. Higher parasitism activity was observed during periods of moderate temperature and increased leafhopper oviposition. Certain parasitoid species exhibited broad host associations, whereas others demonstrated specificity toward particular cicadellid hosts. Natural parasitism levels indicated that mymarid parasitoids contribute significantly to suppression of leafhopper populations under field conditions. Vegetable fields managed with reduced insecticide applications supported greater parasitoid diversity and abundance compared with intensively treated systems. The discovery of new mymarid records expands current knowledge of hymenopteran biodiversity associated with vegetable agroecosystems and highlights the ecological importance of indigenous egg parasitoids in biological control programs.