Lichen : classification based on forming fungi

(i) Ascolichen : If the lichen forming fungus belongs to the class of Ascomycetes then it is called ascolichen. E.g. Rhizocarpon macrosporum.
(ii) Basidiolichen : If the lichen forming fungus belongs to the class Basidiomycetes then it is called Basidiolichen. For example – Clavaria mucida.
(iii) Deuterolichen : If the lichen-forming fungi belong to the class of Deuteromycetes, they are called deuterolichens. Such as Racodium rupestre, Leparia incana etc.

Lichen : Habitat classification

(i) Corticolous : This lichen grows on the bark or stems of trees in tropical regions. Like- Graphis scripta, Evernia prunastri, Parmelia sulcata, Usnea barbata etc.
(ii) Terricolous : They grow in moist and upland soils. For example – Collema tenax, Cladonia leporina, Lecidea atrobrunnea, Cora pavonia etc.
(iii) Sexicolous : They grow on rocks or rocks in temperate regions. Such as Xanthoria calcicola, Aspicilia contorta, Dermatocarpon miniatum etc.
(iv) Lignicolous: They grow on wet wood. Such as Calicium lenticulare, Chaenotheca trichialis, Cyphelium notarisii, Piptoporus betulinus etc.
(v) Foliicolous : They grow on the leaves of ferns or succulent plants. Like Porina epiphylla, Strigula angulul etc.
(vi) Omnicolous : They grow on leather, wood, iron etc. For example, Lecanora dispersa.