Composition of Necrophagous Insect Assemblages in Altitudinal Gradient of Central Chile

This study evaluated whether necrophagous arthropod assemblages, with emphasis on Calliphoridae (Diptera), differ among three sites in central Chile: Coastal (50 masl), Pre-mountain range (1000 masl), and High Andean (1800 masl). We analyzed differences in the abundance, richness, and community composition of arthropods associated with decomposed bait. Specimens were collected using carrion traps and active sampling. In total, 1240 specimens (predominantly insects) were obtained across three orders: Diptera (n = 1216), Hymenoptera (n = 22), and Neuroptera (n = 1). Within Diptera, the families recorded were Calliphoridae (n = 947), Muscidae (n = 118), Piophilidae (n = 77), Fanniidae (n = 44), Sarcophagidae (n = 15), Mycetophilidae (n = 8), Phoridae (n = 5), and Ulidiidae (n = 2). No significant differences were detected in total arthropod abundance or Calliphoridae abundance among sites. Necrophagous arthropod richness was highest at the Coastal and Pre-Andean sites. For Calliphoridae, no significant differences were observed among sites for the evaluated ecological parameters. Indicator taxa at the Coastal site included Braconidae (Hymenoptera) and the dipteran families Fanniidae and Muscidae. At the High Andean site, blowflies (Diptera: Calliphoridae), including Chrysomya albiceps, Compsomyiops fulvicrura, Lucilia cuprina, and Lucilia sericata, were identified as indicators. All Calliphoridae species sampled were confirmed as potentially forensically relevant for the region due to their necrophagous habits. Beyond documenting Calliphoridae across elevation, this study provides baseline data to support future work using this taxon to assess environmental impacts, characterize local trophic interactions, and inform forensic applications.