Current Research Projects - Lichenicolous fungi:


Lichenicolous fungi live obligately on lichens, as broad-spectrum pathogens, host-specific parasites or commensals. Approximately 1800 species of lichenicolous fungi have been described within a wide range of phylogenetic groups.

Over 95% of lichenicolous fungi are members of various groups of the Ascomycota, and most of these are highly host-specific, relatively nonvirulent parasites. Lichenicolous basidiomycetes are also diverse but far less numerous. Many basidiomycetous members, especially of the mushroom-forming clades, exhibit unusually broad host ranges.

It is estimated that there may be 3000-5000 species of lichenicolous fungi globally, of which the European forms are best known at present. Most of the floras of the rest of the world have not been well-studied.

A systematic listing of described lichenicolous fungi (modified from Lawrey and Diederich 2003), including numbers of species, links to fungal isolates available from culture collections, links to published genetic sequences, and relevant literature is available at



In our lab, lichenicolous fungi are isolated in pure culture for experimental study of the associations. Isolated fungi are also sequenced for phylogenetic placement and study of the evolution of the lichenicolous habit.

Results of our studies and those of other labs indicate that:

  • For reasons that are not yet clear, lichenicolous fungi are difficult to isolate and maintain in culture. Especially difficult are gall-forming and host-specialist groups. Broad-spectrum pathogens are the easiest to isolate.
  • Isolated lichenicoles grow on a variety of standard fungal media and on lichen thallus material in the lab.
  • Isolated lichenicolous fungi are frequently tolerant of lichen secondary metabolites that are inhibitory to other nonlichenicolous fungi.
  • Lichenicolous fungi are known to break down inhibitory lichen defense compounds in culture.
  • The lichenicolous habit has evolved in a wide diversity of fungal lineages from ancestors that were saprotrophic, pathogenic or mutualistic.



Illosporiopsis christiansenii Germany, Nordeifel, on Physcia tenella  2006 by Norbert Stapper. From http://www.lichenology.info.

Opegrapha on Heterodermia


Opegrapha melanospila on Heterodermia sp.






Xanthoriicola physciae France (Lorr.), Moselle, Sierck, on Xanthoria parietina, 2005  2005 by N. Stapper. From http://www.lichenology.info.

Xanthoriicola in culture

Isolated X. physciae in culture.
by P. Diederich