Refractohilum pluriseptatum

A hyphomycetous  fungus, lichenicolous on Pachyphiale carneola in old woodlands, with two older records from Scotland but also found in the New Forest in 2024 and may be more widespread. The bristle of hyaline conidiophores should be looked for on more scruffy thalli of the host, turned orange from exposed Trentepohlia algae, rather than the typical white thalli. The mature multiseptate conidia are very distinctive, narrowing abruptly towards the tip, and are longer (>20µm long) than those of other Refractohilum species. See Roux et al (1997).