Molecular data place the hyphomycetous lichenicolous genus Sclerococcum close to Dactylospora (Eurotiomycetes) and S. parmeliae in Cladophialophora (Chaetothyriales)

The lichenicolous anamorphic fungus Sclerococcum parmeliae was isolated in pure culture, and ITS, nuLSU and mtSSU sequences were obtained from these isolates. For comparison, sequences from S. sphaerale, the generic type, were obtained directly from freshly collected specimens. Phylogenetic analyses place S. sphaerale with species of Dactylospora and an unidentified lichen-inhabiting isolate in a strongly supported clade that is sister to a lineage comprising members of the Chaetothyriales and Pyrenulales. In contrast, S. parmeliae is inferred as a member of the Herpotrichiellaceae (Chaetothyriales) and belongs to a robustly supported clade that also includes species of Cladophialophora, Capronia semiimmersa, and Phialophora verrucosa. Within the Herpotrichiellaceae, S. parmeliae most closely resembles members of the anamorph genus Cladophialophora. Accordingly, we propose the transfer of S. parmeliae and the morphologically similar species S. cladoniae, S. hawksworthii and S. normandinae to Cladophialophora. A new lichenicolous species, Clad. megalosporae, collected twice on Megalospora in Florida and Papua New Guinea, is also described.