The Thar Desert of northwestern India harbours underdocumented parasitoid–host interactions and unique ecological interactions often overlooked due to its arid landscapes. Here, we report the first confirmed host association of Brachymeria apicicornis (Cameron, 1911) (Chalcididae: Brachymeriinae) as a pupal parasitoid of Cassida obtusata Boheman, 1854 (Chrysomelidae: Cassidinae) feeding on Amaranthus palmeri S. Wats (Amaranthaceae) in Rajasthan, India. Solitarily emerged adult parasitoids from five individually isolated pupae establish a pupal idiobiontic parasitoidism on the cassidine host. Species identity is corroborated through a diagnostic redescription. The present study also provides a structured evidence framework encompassing rearing isolation, emergence chronology, exit-hole morphology and position, and host pupal phenotype. Broader implications on ecological dynamics in arid landscapes are also discussed.
V. et al. (Mon,) studied this question.