Phylogeny and taxonomy of the Inonotus linteus complex

The Inonotus linteus complex comprises several closely related species characterized by pileate basidiomes, a heterogeneous hyphal system with a monomitic context and a dimitic hymenophoral trama. Setae are hymenial and basidiospores are broadly ellipsoid to subglobose, yellowish and thick-walled. Research to understand this complex have been particularly noticeable in East Asia. In the present paper, the complex was studied at a larger scale, including samples from Mesoamerica. Inonotus linteus, an epitype of this species being designated here, is circumscribed as a narrow sense based on morphological and phylogenetic data, and this has lead to delimiting a new species from Mesoamerica, viz. I. cubensis, and provides evidence for two additional species, I. alpinus and I. zonatus, from East Asia. Phylogenetic analyses of ITS sequences also confirmed the status of I. baumii, I. linteus, I. lonicericola, I. lonicerinus, I. vaninii, I. sanghuang, I. weigelae and I. weirianus as distinct taxa, while I. tenuicontextus is considered to be a synonym of I. weigelae. A key to 11 species in the complex is provided.