Boreusella

Boreusella is a genus of fungi in the family Tricholomataceae. It was first described by mycologist Rolf Singer in 1951. The genus is characterized by its small, cup-shaped basidiocarps, which are typically found growing on the bark of trees, particularly on conifers. Boreusella species are known for their distinctive, often reddish-brown to brown spore prints.

The genus includes several species, with Boreusella pini being one of the most well-known. This species is commonly found in Europe and North America, often growing on the bark of pine trees. It produces small, cup-shaped fruiting bodies that are typically 1-2 cm in diameter. The spores are smooth and ellipsoid, measuring about 6-8 by 4-5 micrometers.

Boreusella fungi are saprobic, meaning they obtain nutrients by decomposing organic matter. They play an important role in the ecosystem by breaking down dead plant material and recycling nutrients. Despite their small size, Boreusella species can be an important food source for certain insects and other small organisms.

The taxonomy of Boreusella has been a subject of debate among mycologists. Some species have been reclassified or moved to other genera, such as Hypholoma and Mycena. However, the genus remains a useful tool for identifying and studying the diverse world of fungi.