Bjerkandera
Bjerkandera is a genus of wood-rotting fungi in the family Meruliaceae. Taxonomy. The genus was circumscribed by Finnish mycologist Petter Adolf Karsten in 1879. The type species, "B. adusta", was originally described as "Boletus adustus" by Carl Ludwig Willdenow in 1787. The generic name honours Swedish naturalist Clas Bjerkander. Karsten included seven species in addition to the type: "B. dichroa", "B. amorpha", "B. fumosa", "B. kymatodes", "B. diffusa", and "B. isabellina". Most of those species have been since moved to different genera or synonymized. In a 1913 survey of polypore genera, Adeline Ames included "B. adusta", "B. fumosa , and B. puberula"; the latter fungus is now placed in "Abortiporus". Marinus Anton Donk included only "B. adusta" and "B. fumosa" in a 1974 publication. Some authors have suggested to merge these two species into other genera, such as "Gloeoporus", "Tyromyces", or "Grifola". Molecular phylogenetic analysis has demonstrated that the two traditional "Bjerkandera" fungi form a monophyletic group that is sister to the crust fungus "Terana coerulea". The little-known Cuban species "B. subsimulans" and "B. terebrans", both originally described by Miles Berkeley and Moses Ashley Curtis, were transferred to "Bjerkandera" by William Alphonso Murrill in 1907, and are accepted  as valid species by Index Fungorum. "Bjerkandera atroalba" and "B. centroamericana" are two neotropical species that were transferred to "Bjerkandera", and described as new, respectively, in 2015. In 2021 four new species were added from South America and Asia. Description. The fruit bodies of "Bjerkandera" fungi have soft and pliable caps with an upper surface texture ranging from finely hairy to smooth. The pore surface on the undersurface of the cap ranges from grey to black or buff to greyish brown. The tubes are the same colour. A dark, denser zone is typically present between tubes and the context, which  is usually white to buff. The hyphal system in "Bjerkandera" is monomitic, containing only generative hyphae. These hyphae have clamps, and are thin to thick-walled. Cystidia are absent from the hymenium. The spores of "Bjerkandera" are smooth with a short cylindrical shape, thin-walled, and do not react in Melzer's reagent. Habitat and distribution. "Bjerkandera" fungi usually grow on hardwoods, and are rarely on conifers. They cause a white rot.