Involvement of larder beetles (Coleoptera: Dermestidae) on human cadavers: a review of 81 forensic cases

From 1994 to 2013, French forensic entomology laboratories investigated 1,093 cases. Larder beetles (Coleoptera: Dermestidae) were observed in 81 (7.5 %) of these cases. To describe and analyze these 81 cases, eight parameters were used: city, location (indoor or outdoor), decay stage (fresh, decay, or dry), dermestid species and instar (adults and/or larvae), presence of living calliphorid larvae, presence of calliphorid pupae or adults, and presence of other necrophagous species. Eight Dermestidae species were observed: Dermestes frischii (42 % of cases), Dermestes undulatus (35.8 %), Dermestes peruvianus (12.3 %), Dermestes lardarius (9.9 %), Dermestes haemorrhoidalis (8.6 %), Dermestes maculatus (7.4 %), Dermestes bicolor (3.7 %), and Dermestes ater (1.2 %). Larder beetles primarily developed on human cadavers in outdoor locations in areas with a dry climate and were never reported in oceanic areas (which are characterized by frequent rainfall and high ambient humidity). The number of dermestid species on a single corpse never exceeded three. Typically, one species was found per corpse. Species differed between indoor and outdoor cases, with D. frischii and D. undulatus dominant in outdoor cases, while D. peruvianus dominant in indoor cases. Calliphoridae was found in 88 % of the cases, while Hydrotaea and Piophilidae were observed 40 % of the time. Regarding Coleoptera, Necrobia spp. (Coleoptera: Cleridae) was observed in 46 % of the cases. Lastly, we observed a typical decomposition pattern, with preferential feeding areas on the face, hands, and feet (i.e., the extremities). Pupation chambers on or inside the bones were not observed.