Exploring the diversity of culturable fungi on corpses for forensic applications

Abstract Fungi form part of saprotrophic communities that are responsible for the decomposition of carrion and corpses. While necrophagous insects are known in detail and can be therefore used for forensic investigation, information provided by fungi is rarely used in forensic investigations. By the present study, we further our understanding of fungal diversity on corpses in order to make fungi useful for forensic investigation. We sampled macroscopically visible microfungi on 36 corpses at the place of discovery or at the Institute of Legal Medicine in Frankfurt am Main. Forty-seven strains of fungi were isolated, cultivated, and identified based on morphological characteristics and molecular barcoding. Together with records of fungi on corpses found in literature, this information is compiled in a checklist which contains 306 records and context information on 104 species of fungi. By our investigation, 17 species of fungi have been detected for corpses for the first time. Information on localities and the decomposition stages of the corpses is compared to characteristics of fungal species as known by literature. Many fungal species use a broad spectrum of substrates in diverse habitats, but some indicate special circumstances concerning the habitat, humidity, and temperature. The degree of decomposition of the corpses significantly correlates negatively with the value of water activity for optimal growth of individual fungal species. The checklist is a first step for the documentation of the diversity of culturable fungi on corpses, but it is still very incomplete. More records of microfungi on corpses are required, and more detailed information on characteristics of individual fungal species is needed in order to interpret and use the occurrence of fungi for criminal investigation.