Evaluation of the lichen flora of the Northern Andes must be based on a restricted number of better-known groups, probably less than 25% of the flora. This is because our knowledge of the taxonomy and distribution of lichens in the Tropics is still very incomplete.

In the Andes, the groups with foliose and fruticose growth forms are particularly well represented; the crustose group seems less important. This is in contrast with the surrounding lowlands, where crustose is the dominant growth form. At higher taxonomic levels there is a resemblance in taxonomic composition with the cooler zones of the world, which disappears at the generic or sectional levels. A conspicuous morphological feature is the frequency of foliose lichens with linear, rhizinate, or ciliate lobes, probably an adaptation to very humid conditions.

More than half of the species have a wide distribution throughout the Tropics or at least in the Neotropics. Among the more restricted taxa is a humid montane element. At the highest elevations a temperate element is apparent, usually with bicentric distribution in both hemispheres. Perhaps 10% of the species are known only from the region; local endemism is probably very scarce. A few taxa appear to be restricted to Ecuador and southern Colombia or Venezuela; so far, only a single species is known with certainty to be restricted to the humid páramos of Colombia. There are distinct affinities with the lichen flora of southeastern Brazil and the Caribbean–Central American area but not with the adjacent Guayana Highland.