Lichens of Sri Lanka: Past discoveries, present knowledge, and future directions

Lichens are an important component of Sri Lankan biodiversity and have contributed greatly to the tropical diversity as well as to their application as bioindicators of changing environmental conditions. This review summarises 49 selected research publications on the taxonomic and chemical diversity of lichens, their application as bioindicators, and as a source of bioactive compounds that have medicinal properties against microorganisms with the potential of curing some diseases. The chemical properties of lichens and associated fungi and mycobionts have been a major focus in recent years, and several useful compounds have been identified that have benefits for human health. Several areas of the country are well surveyed and further surveys in new areas will aim to discover new species and document lichen diversity, and responses to environmental pollution. These results highlighted the importance of ongoing research in Sri Lanka in a tropical and global lichen context.