Succession of necrophagous insects over winter in an urban area of southern Italy

Over the past years, application of entomological evidence has contributed significantly to forensic investigation. Forensic entomology combines aspects of insect development, behaviour and ecology with investigative techniques. The most common application is the estimation of post mortem interval (PMI) by determining a minimum period of insect activity on a decomposing body. In this evaluation, an assessment of physical condition of the body must be combined with an assessment of the fauna associated with the body For this purpose, the correct identification of insect species recovered on the body is essential, along with a knowledge of their biological and ecological relationships with the local fauna. An experimental investigation on the insect fauna of decaying corpse has been carried out on animal carrion (baby pig) placed in an urban habitat of Bari (Southern Italy). We have intentionally limited our researches to the study of necrophagous insects of the early postmortem period and their succession, for a better definition of the time since death, in the earliest stages of decomposition. Data concerning climatological conditions, body decomposition and insect activity have been recorded daily. Ambient temperature and internal body temperature have been monitored using two Data Loggers. We have indeed analysed the time necessary for egg deposition, egg hatching, larvae development and pupation of blowflies based on different parameters such as degree of decay and seasonal weather (lighting, temperature, humidity, rainfall). Entomological specimens have periodically been collected from the corpse. Insect identification has been carried out based on the available identification keys combined with genetic analysis of COI and COII to establish morphological peculiarity of various stages of development and genetic sequences of every specimen collected from the carcass.