The diversity of endolichenic fungi – A review

Abstract

Endolichenic fungi reside inside the lichen thalli without showing any visible symptoms of their presence. The fossil record of endolichenic fungi dates back to 415 million years, however, they have been successfully isolated only since the 1990s. Several reviews are available dealing with the bioprospecting potential of unique metabolites produced by endolichenic fungi; however, reviews addressing their taxonomic diversity are lacking. In this review, the names and the current taxonomic status of the endolichenic fungi reported so far are compiled and updated. The study indicated that approximately 500 endolichenic fungi are isolated of which only 135 identified up to species level. A large number of endolichenic fungi are either partially identified up to genus level or treated as unidentified. The reasons for such treatment are discussed. The study also revealed that only 114 well-known species of lichens belonging to 22 families are utilized for isolation of endolichenic fungi, while in some cases hosts were not identified. These lichens belong mostly to macro lichens with Parmeliaceae as the dominant members. The occurrence of the endolichenic fungi on different groups of plants indicates that they are not host-specific.