Triadelphia morgoensis, an enigmatic wood-associated hyphomycete: second record, updated description and molecular identification.

Triadelphia (Ascomycota, Microascales) is a genus encompassing pleomorphic dematiaceous micromycetes occurring sporadically on rotting wood and other plant material, infrequently also on other substrates. In this study, we document a second record of Triadelphia morgoensis, found on a twig of Populus nigra near Prague (Czech Republic), after its original description from decaying wood in Hungary. This fungus is characterised by the production of three types of conidia. The identification was achieved by a combination of morphological, physiological and genetic traits. The description of the fungus is emended, and its differentiation from similar species is discussed. Multigene phylogeny showed that T. morgoensis is most closely related to T. loudetiae and T. heterospora. The DNA data from three loci generated in this study (ITS, LSU, RPB2) will facilitate identification of the species in the future. Our results add to the knowledge on the ecology and phylogeny of this understudied fungus, for which neither living type material nor a molecular sequence has been preserved.