The researchers found the species at the Isojärvi National Park and the Hallinmäki protected area in Jämsä.
The species grows on the bark of decaying trees and its foot looks like covered with white powder, said Panu Halme, a researcher from the University of Jyväskylä.
The species has previously been discovered in Norway and Sweden.
Majority of unknown mushroom species discovered by researchers in the past have been very small ascomycetes or nearly invisible to the naked eye.
Species new to science can still be found in Finnish forests when different researchers collaborate.
An abundant number of small-sized wood-decay fungi which have not even been described scientifically and had never before been spotted in the country seem to lie in decaying birch woods in southern Finland’s low pristine forests.