Diversity and new distributional records of parasitoid species (Hymenoptera) in poultry facilities in the Brazilian Pampa

ABSTRACT Poultry production systems create favorable conditions for the proliferation of synanthropic flies, which negatively affect animal health and productivity through the transmission of pathogens. Despite their economic and sanitary importance, data on the diversity of flies and their associated parasitoids remain scarce in southern Brazil, particularly within the South American Pampa biome. The present study investigated the diversity and seasonal occurrence of parasitoid Hymenoptera emerging from fly pupae collected in poultry manure, with emphasis on new distributional records. Between October 2022 and March 2023, a total of 2,372 fly pupae were collected in Pelotas, Rio Grande do Sul, of which 30.73% were parasitized. From these, 1,492 parasitoids belonging to the families Pteromalidae, Braconidae, and Encyrtidae emerged. The house fly Musca domestica represented 70.87% of all flies collected. Among the parasitoids, Nasonia vitripennis, Pachycrepoideus vindemmiae, and Spalangia endius were the most abundant and frequent species. Notably, Aphaereta muesebecki is reported here for the first time in South America, and new regional records are provided for Aphaereta laeviuscula. These results expand the known distribution of parasitoid taxa associated with synanthropic flies and highlight the ecological relevance of native parasitoid communities for the development of integrated pest management strategies in poultry production systems.