Two new Agaricomycetes related to post-fire mosses

The very hot summers of recent years have led to an increase in the number of large forest fires in Europe. We investigated four large fire sites in Brandenburg and Saxony (Germany) up to 4 years after the fires with a focus on studying the post-fire fungal communities. In this context, we documented two species of Agaricomycetes associated with mosses, which are common but particularly emerge on burnt areas, i.e., Arrhenia bryophthora sp. nov. and Bryopistillaria clavarioides sp. nov. The former is an agaric with omphalinoid habit that causes the dieback of the common moss Ceratodon purpureus; the latter is a clavarioid fungus associated with either Ceratodon purpureus or another common moss, Funaria hygrometrica. Both fungal species appear to be restricted to recently burnt areas and have otherwise not been observed on or in close vicinity of these mosses. Herein, we describe these fungi macro- and micromorphologically as well as on a molecular basis and discuss their taxonomic position and potential lifestyles.