The cyanolichen genus Epiphloea is currently included within the Heppiaceae (Lichinomycetes) based on ascus characteristics. The presumed presence of a prototunicate ascus has been used as support for this classification, despite the incongruence with other characters (e.g. spores). Here, we use a molecular phylogeny of the two markers mtSSU rDNA and Mcm7 to investigate the position of Epiphloea. In addition, we have re-investigated the ascus characteristics. Our results place the two species, Epiphloea byssina and E. terrena, within the Collemataceae, nested in Leptogium s. str. The ascus type in both species is shown to be Lecanoralean and similar to the ascus in other Collemataceae, with a strongly amyloid tube-like structure. This observation supports the placement within Lecanoromycetes and refutes the earlier suggested affinities with Heppiaceae and Lichinomycetes. The correct names for these species are Leptogium byssinum and Leptogium terrenum.

Leptogium quercicola (Collemataceae), a new corticolous species, is described from central and south-eastern Spain. It is closely related to L. lichenoides, but differs in the development of dense fruticolous cushions, with lobes narrower than the smallest known forms of L. lichenoides. Moreover, spore length and width of the two taxa are significantly different. In addition, the two species differ ecologically; L. quercicola growing directly on bark of Quercus spp., while L. lichenoides colonizes rocks, soil and bark but always among mosses.