It is the only genus in the monotypic family Abrothallaceae, which itself is the sole taxon in the order Abrothallales.

[2] The genus was circumscribed by the Italian botanist Giuseppe De Notaris in 1849.

[3] The classification of the genus in either family or order was uncertain until molecular phylogenetic analysis revealed the group as an independent lineage in the class Dothideomycetes.

Both the family and the order were circumscribed in 2013 by Sergio Pérez-Ortega and Ave Suija.

These include: spherical (or nearly so) ascomata without a margin or well-defined edge that are sometimes dusted with golden or green pruina; bitunicate asci (i.e., with two functional ascal wall layers) that have four to eight ascospores; brown, 2- to 4-celled, warted asymmetric ascospores; paraphyses that are ramified-anastomosed; and the presence of an epihymenium (the uppermost layer of the hymenium) with granulose pigments that often dissolve in potassium hydroxide.