New Records of Aphelinidae (Hymenoptera) Parasitoids of Mealybugs on Grapevine in Semi-Arid Vineyards

Abstract

Documentation of aphelinid parasitoids associated with mealybugs infesting grapevine in semi-arid vineyard ecosystems was undertaken through systematic surveys, field collections, and laboratory rearing. Mealybug populations predominantly infesting Vitis vinifera were sampled across multiple vineyard blocks, and associated parasitoids were reared and identified using morphological characters supported by mitochondrial COI barcoding. New distributional records of Aphelinidae species were confirmed, expanding the known host–parasitoid associations in arid viticultural landscapes. Parasitism levels varied spatially and temporally, ranging from low incidence in early-season infestations to significantly higher rates during peak mealybug density periods. Encarsia spp. and Coccophagus spp. were the dominant aphelinid taxa recovered, indicating their adaptive colonization of semi-arid agroecosystems. Phylogenetic placement of representative specimens revealed close affinity with previously reported populations from Mediterranean and subtropical regions, suggesting possible dispersal via agricultural trade routes and climatic similarity. The presence of multiple parasitoid species within single mealybug colonies indicates potential for natural biological control, although overall parasitism was insufficient to suppress outbreak-level infestations without supplementary management interventions. Environmental variables such as temperature, humidity, and vineyard canopy structure were observed to influence parasitoid activity and host accessibility. The findings emphasize the importance of conserving native parasitoid diversity and integrating habitat management strategies to enhance biological control efficiency in vineyard pest management systems. These new records contribute to the global inventory of Aphelinidae diversity and provide baseline information for future augmentation and conservation biological control programs targeting mealybugs in grape production systems under changing climatic conditions in semi-arid regions supporting sustainable integrated pest management strategies in viticulture.