Six new species of from hardwood trees in Poland.

(, ) is a well-supported monophyletic lineage within the , species of which occur in a diverse range of habitats including on forest trees, in the soil, associated with bark beetles and mites as well as on the fruiting bodies of some . Several species have also been reported as important human and animal pathogens. During surveys of insect- and wound-associated from hardwood trees in Poland, many isolates with affinity to were recovered. In the present study, six undescribed spp. collected during these surveys are characterized based on their morphological characteristics and multi-locus phylogenenetic inference. They are described as , , , , , and . Two of the spp. reside in the -complex, while one forms part of the -complex. One sp. is a member of lineage F, and two other species grouped outside any of the currently defined species complexes. All the newly described species were recovered from hardwood habitats in association with sub-cortical insects, wounds or woodpecker cavities. These species were morphologically similar, with predominantly asexual states having hyaline or lightly pigmented conidia, which produce holoblastically on denticulate conidiogenous cells. Five of the new taxa produce ascomata with necks terminating in long ostiolar hyphae and allantoid ascospores without sheaths. The results suggest that species are common members of the in hardwood ecosystems of Poland.