Four new species of Acarosporaceae (Acarosporales, Lecanoromycetes) with carbonized epihymenial accretions from China

Based on a combination of morphological, chemical, and phylogenetic analyses, we report four new species from China: Acarospora carbonacea, A. rorida, Sarcogyne knudsenii, and S. xizangensis. These four species are characterized by endolithic thalli, apothecia with carbonized epihymenial accretions, an Acarospora - type ascus, and the absence of secondary metabolites. Acarospora carbonacea sometimes can develop a white epilithic ecorticate thallus, whereas such a thallus is not observed in the other three species.

Comprehensive descriptions, detailed illustrations, and phylogenetic analyses of the four new species are provided. In addition, a compiled species checklist summarizing the diagnostic features of the eight reported species of Acarosporaceae with carbonized epihymenial accretions in China is presented.