Human bodies suffer a series of physicochemical and microbiological changes that modify their anatomy. When necrophagous insects accelerate the decomposition process, it results to a difficulty for the forensic pathologist to establish the death cause. However, entomological evidence on cadavers has been used as a tool in criminal investigations such as clarifying the death causes, geographical location, and eventually transfer of the body (Smith 1986; González et al. 2011; Nuñez 2012).
The entomologist’s work begins when there is entomological evidence, which requires a specialized study of the species involved, stage of development in which the insect was collected, life cycle, and other aspects of its biology. When obtaining this data, it is sought to provide information within the forensic context: primary species colonizer, ecological succession, development at the temperature of the event site, geographical location, and environmental factors help to estimate the minimum postmortem interval (mPMI), as well as other circumstances regarding the cause of death (Gennard 2007; Amendt et al. 2010).
Venezuela has experienced soaring rates of violent crime, in particular, homicides (Tremaria 2016; UNODC 2019). Data regarded from a non-governmental organization known as the Venezuelan Violence Observatory provides information on homicide rates and showed that the Aragua state presents the highest homicide rate in the last 5 years (142 to 168 crimes per 100,000 inhabitants). All these cases are transferred to the estate morgue, located in Caña de Azúcar neighborhood at 130 km from the Caracas. This morgue has two main spaces: the body holding area with mortuary refrigerators for storage and the autopsy room area. However, since 2015, the refrigerators are only partially operational and serve for short-term storage only. Thus, all bodies are placed in the autopsy room in postmortem tables. After, autopsy unclaimed bodies are returned temporarily to the mortuary refrigerators. Under these conditions, some sarcosaprophagous Diptera species colonized some exposed bodies in the morgue area facilities.
From an entomological point of view, in Aragua state are recorded 36 flies species (23 Calliphoridae and 13 Muscidae), with eight species reported in forensic studies: Calliphora vicina Robineau-Desvoidy, 1830, Chrysomya albiceps (Wiedemann, 1819), C. megacephala (Fabricius, 1794), Lucilia sericata (Meigen, 1826), L. cluvia (Walker, 1849), L. cuprina (Wiedemann, 1830), Cochliomyia macellaria (Fabricius, 1775), and Musca domestica Linnaeus, 1758 (Cova-García 1964; Magaña et al. 2006; Löwenberg-Neto and Carvalho 2013; Thomas 2014; Velásquez et al. 2017).
This study aims to characterize the Diptera species, particularly Calliphoridae and Muscidae, present on bodies that arrived for autopsy at the Caña de Azúcar morgue, Aragua. This investigation can contribute to the creation of a database of local dipterans species of medico-legal importance in Venezuela.