CARRION INSECT SUCCESSION IN AN ARID ENVIRONMENT FROM SAN JUAN, ARGENTINA

CORTEZ VEGA AR; ABALLAY F; DÍAZ NIETO LM

Encuentro; XLI Reunión Científica Anual de la Sociedad de Biología de Cuyo; 2023

Forensic entomology aims to determine Post Mortem Interval (PMI) or the time between the death and discovery of the body using associatedarthropods with dead bodies. Diptera and Coleoptera are the most important forensic orders, arriving at decomposed bodies following aspecific sequence know as ecological succession. This succession is affected by the size of carrion resources, temperature, and particularweather and biogeographical conditions of each region. This study aims to know the composition and succession pattern of forensic insectsand their relationship with the various stages of decomposition states in pigs during spring in an arid location in San Juan, Argentina. Thisstudy was conducted in Medanos Grandes, Caucete, in October 2021. Three pig carcasses were used as models of vertebrate carriondecomposition and were sampled with daily base from Fresh to Remains stages. Pitfall traps, entomological nets, and hand-picking wereused to collect immature and adult arthropods. A total of 24322 specimens were collected from 10 orders and 32 families. The following flyspecies were identified: Chrysomya albiceps, Cochliomyia macellaria, Compsomyiops fulvicrura, Lucilia sericata and Sarconesiachlorogaster (Calliphoridae), Fannia fusconotata, F. sanihue, F. heydenni and F. femoralis (Fanniidae), Musca domestica, Muscinastabulans, Dolichophaonia trigona and Ophyra aenescens (Muscidae), Piophila casei (Piophilidae), Sarcophagidae, Anthomyidae, andPhoridae. Coleoptera species were identified: Necrobia rufipes (Cleridae), Dermestes maculatus (Dermestidae), Euspilotus eremita, E.lacordairei, E. lepidus, E. modestus, E. pavidus, E. golbachi and Xerosaprinus dyptichus (Histeridae), Anthicidae, Nitidulidae, Scarabaeidae,Staphylinidae, Tenebrionidae, and Trogidae. The arrival of Co. macellaria and Sarcophagidae flies, followed by F. fusconotata, M.domestica, C. fulvicrura, S. chlorogaster, M. stabulans, and O. aenescens was characteristic in the Fresh stage. Furthermore, in this state, weobserved Calliphoridae eggs and Sarcophagidae, and Co. macellaria larvae. P. casei flies and Staphylinidae, Trogidae, and D. maculatusbeetles were recorded in the Bloated stage. Larvae of Co. macellaria, C. fulvicrura, C. albiceps, M. domestica, O. aenescens and adults ofC. albiceps were registered in late Bloated and the early Active Decay stages. About the beetles, Anthicidae, Histeridae, Cleridae and D.maculatus larvae were registered. Larvae of P. casei were characteristic mainly in the Advanced Decay stage. In Remain stage, the absenceof Calliphoridae larvae and the presence of larvae P. casei and D. maculatus were registered. Calliphoridae and Sarcophagidae flies wereprimary colonizers of carcasses. Histeridae, Cleridae, Staphylinidae, and Anthicidae families bettles and C. albiceps larvae fly showednecrophilic behavior, feeding on immature stages of flies. This research contributes to the characterization of the succession of carrion insects,recording variations between decomposition stages in the arid environment of San Juan, Argentina.