Naevia

Naevia is a small genus of fungi in the family Arthoniaceae. Unlike most members of their family, these fungi do not form lichens because they lack algal partners and instead obtain nutrients by decomposing dead bark material. They appear as tiny black dots scattered across the smooth bark of trees and shrubs, where they act as early colonisers of fresh bark surfaces. The genus was historically confused with the related lichen-forming genus Arthonia, but modern molecular phylogenetics studies have confirmed that Naevia represents a distinct evolutionary lineage of non-lichenised fungi....read more on Wikipedia.