Botryotrichum murorum is a common soil and indoor fungus resembling members of the genus Chaetomium. The fungus has no known asexual state, and unlike many related fungi, is intolerant of high heat exhibiting limited growth when incubated at temperatures over 35 °C. In rare cases, the fungus is an opportunistic pathogen of marine animals and humans causing cutaneous and subcutaneous infection.
Chaetomium murorum was first discovered by August Carl Joseph Corda in 1837 when he sampled the fungus from a wall in Prague. The Latin name “murorum” means “wall”. In 2016 X. W. Wang et al. re-examined a set of cultures of Chaetomium-like fungi using phylogenetic analysis of the DNA directed RNA polymerase II subunit gene sequence. Chaetomium murorum, together with the genus Emilmuelleria, were then transferred to the genus Botryotrichum as the phylogenetic analysis confirmed that they clustered in the Botryotrichum clade. The current name for C. murorum is B. murorum.
Botryotrichum murorum is a soil fungus also known to occur on animal dung of a range of animals including birds. It is also commonly found in indoor environment and on crops including sugarcane, rice, banana, pea, pumpkin, and cucumber.B. murorum is mesophilic with the optimum growing temperature of 20–30 °C (68–86 °F). It exhibits limited growth rate at 35 °C and above. This species grows on a wide range of microbiological growth media under standard clinical laboratory culture conditions, including oatmeal agar (OA), potato carrot agar (PCA), dichloran 18% glycerol agar (DG18), malt extract agar (MEA), and has shown to be able to metabolize keratin. Along with other close related species of Chaetomium such as C. globosum and C. funicola, B. murorum can degrade cellulose material in paper, as it expresses cellulase,xylanase, peroxidase, and laccase activities. The fungus can be utilized in waste degradation biotechnology.