Silent witnesses: basidiomycota as forensic biomarkers in human decomposition

Although forensic mycology has primarily focused on microscale Ascomycota and successional patterns, this review emphasizes the underexplored potential of macroscopic Basidiomycota as biomarkers in decomposition ecology. These taxa require quantitative validation prior to application. We present a conceptual synthesis and hypothesis-generating framework, rather than a formal systematic review. We did not utilize pre-registered criteria, formal protocols, or bias assessment. Consequently, conclusions are provisional and intended to encourage empirical validation. Focusing on ammonia fungi and late-stage decomposers, we demonstrate their forensic value through nitrogen-responsive colonization, enzyme-mediated specificity for recalcitrant tissues, and physical persistence of sporocarps and mycelial networks that outlast insect evidence. Unlike transient microbial communities, these fungi form durable, anchored sporocarps detectable in challenging environments where conventional methods fail-including arid regions and cold climates. However, in aquatic systems, Basidiomycota succession is reduced, with bacterial communities offering higher resolution for submersion intervals. Habitat-specific constraints require stratified validation before universal applicability is claimed. Their responsiveness to nitrogenous byproducts generates successional patterns that can assist post-mortem interval estimation. Their enzymatic capacity to degrade resistant materials establishes Basidiomycota as a dominant signature during advanced decomposition. Interactions with insects and grave-soil microbiota produce complex networks yielding additional crime scene evidence. Despite this potential, limitations including inconsistent collection protocols, incomplete databases, and environmental variability hinder broader application. We propose integrating fungal surveys with molecular techniques to develop calibrated forensic models. This synthesis identifies Basidiomycota as a promising biomarker, though evidentiary value requires validation through multi-site empirical studies. With rigorous methodological development, these fungi could serve as transformative tools for clandestine grave detection, crime scene reconstruction, and postmortem interval estimation. This review emphasizes the need for expanded research and standardization to realize the evidentiary value of these underutilized forensic indicators.