Sri Lanka is a tropical island situated close to the southern tip of India. It is situated in the middle of Indian Ocean.

Lichens are a mutual relationship between algae or cyanobacteria with a fungus. Therefore it is a composite organism and not plants. Lichens can be found different shapes and forms. They are grouped by thallus type. Thallus growth forms typically correspond to a few basic internal structure types. Common names for lichens often come from a growth form or color that is typical of a lichen genus. Coloration is usually determined by the photosynthetic component.

Sri Lanka is an island, which serves a great diversity vegetation that includes many endemic flora and fauna. George Henry Kendrick Thwaites was the first person to collect lichens in Sri Lanka, in 1868. In 1870, W.A. Leighton examined Thwaites' collection and determined 199 species. In 1900, Almquist's collections in 1879 formed the basis of "Nylander's Lichenes Ceylonenses". In 1932, Arthur Hugh Garfit Alston listed 89 lichen species common to the Kandy district. In 1970, F. Hale collected lichens in lowland rain forests and compiled a regional monograph of Relicina and Thelotremataceae in Sri Lanka. In 1984, Brunnbauer compiled a bibliographic description of lichens in Sri Lanka in 15 fascicles included 550 species belonging to 122 genera and 48 families. During the coming years, many foreign scientists such as Moberg (1986, 1987), Awasthi (1991), Makhija and Patwardhan (1992), Breuss et al. (1997) and Vezda et al. (1997) increased the recorded number of lichens in Sri Lanka up to 659 species.^[1]

Sri Lankan lichen biota has been studied by lichenologist Gothamie Weerakoon along with many other local and foreign researchers. The systematic classification of lichen was started in 2012 by Weerakoon and discovered more than 1200 lichen species from the island. Almost half of the described lichens are represented by the family Graphidaceae. In 2003 during a lichen survey in the Kandy municipal region, about 80 lichen species belonging to 18 families and 32 genera were recorded by Nayanakantha and Gajameragedara. Of them 33 (66%) were crustose lichens, 11 (22%) foliose, 4 (8%) placodioid and the remaining 4% were fruticose and squamulose lichens.^[1]

In 2013, Weerakoon discovered 51 new varieties of Lichens endemic to Sri Lanka, where 8 of them were found from the Knuckles Mountain Range.^[2][3] In 2014, Weerakoon documented over 200 new lichen records from Sri Lanka, with three new species.^[4] While Udeni Jayalal et al. found 2 new lichens from Horton Plains in 2012, as Anzia mahaeliyensis and Anzia flavotenuis.^[5] In 2015, Weerakoon et al. found 6 new Graphidaceae lichens from Horton Plains.^[6] In 2016, Weerakoon and André Aptroot described 64 new records of lichens of Sri Lanka. In May 2016, Weerakoon et al. recorded8 new lichen species and 88 new records from Sri Lanka.^[7]