Taxonomic Insights into the Diversity of Scelio (Hymenoptera: Scelionidae) from Sindh, Pakistan

Scelio Latreille, 1805 is a widely distributed genus of Scelionidae wasps, commonly known as egg parasitoids of acridid grasshoppers and locusts. Despite their potential importance in biological control, Scelio species remain poorly documented in Pakistan. Specimens were collected from seven localities of the Thar Desert during 2021-2023 using Malaise traps, yellow pan traps and sweep-netting. A total of 1,869 specimens were examined, comprising 1,769 females and 100 males. The highest collection was in 2023 (733 specimens; 39.22%), while Umerkot yielded the highest locality-wise abundance (319 specimens; 17.07%) and Nagarparkar the lowest (222 specimens; 11.88%). Nine species were identified: S. aegyptiacus (Priesner, 1951), S. hieroglyphi (Timberlake, 1932), S. mauritanicus (Risbec, 1950), S. oviphagus (Mukerji, 1953), S. poecilopterus Priesner, 1951, S. tristis (Nixon, 1958), S. serdangensis (Timberlake, 1932), S. pakistanensis Siddiqui, Mushtaque & Zafar, 1983 and S. popovi Nixon, 1958, with S. aegyptiacus being the most abundant. We report S. hieroglyphi from Sindh and S. pakistanensis from the Thar region for the first time. Material referable to S. popovi confirms its occurrence, or that of a closely related form, in Pakistan. Taxonomic notes, diagnostic characters, host associations, distributional data and sex-based identification keys are provided. This study improves baseline knowledge of Scelio diversity in Sindh and provides a foundation for future taxonomic, ecological and biological control studies in Pakistan.