Larval identification key to necrophagous Coleoptera of medico-legal importance in the western Palaearctic.

Several necrophagous Coleoptera species are frequently collected on cadavers, may occasionally act as intermediate or paratenic hosts of parasites, as vectors of pathogens or as allergens, and can also represent major pests of preserved animal products. However, despite their medical, veterinary and economic importance, there is a lack of reliable species identification tools for the larval stages (usually the only entomological evidence associated with medicolegal investigations), thus severely limiting their potential application as forensic indicators. Here, we provide an identification key to the larvae of the necrophagous Coleoptera species which have been recorded on carrion in the western Palaearctic region, based on easily observable morphological characters. In total, we provide diagnostic characters for the reliable identification of 23 necrophagous Coleoptera species within four different families (Cleridae, Dermestidae, Nitidulidae and Silphidae). In addition to the aforementioned families, we provide diagnostic characters for the identification of the larvae of families Histeridae, Staphylinidae and Trogidae, which can also be collected on cadavers. It is expected that the present key will facilitate the identification of larval material of necrophagous Coleoptera collected either in carrion succession studies or during medicolegal investigations, in order to further advance in the potential use of this insects as forensic tools.