Megasporoporia
Megasporoporia is a genus of four species of crust fungi in the family Polyporaceae. The genus is characterized by its large spores (after which it is named), and dextrinoid skeletal hyphae. Taxonomy. The genus was circumscribed by mycologists Leif Ryvarden and Jorge Eduardo Wright in 1982, with "Poria setulosa" as the type species. They included an additional three species: the new combinations "M. cavernulosa" and "M. hexagonoides", and the new species "M. mexicana". Six new species of "Megasporoporia" were introduced by Chinese mycologists between 2004 and 2009 as a result of taxonomic studies of wood-inhabiting fungi in China . Molecular analysis showed that "Megasporoporia" nested within the "core polyporoid clade", a grouping of polypore fungi roughly equivalent to a more narrowed but still broad concept of the family Polyporaceae. Later analysis that included the more recently described Chinese species revealed that the genus was not monophyletic and could be divided into four clades. In 2013, two of these monophyletic clades were segregated from "Megasporoporia" and circumscribed as the new genera "Megasporia" and "Megasporoporiella". Description. "Megasporoporia" have crust-like fruit bodies, with large or small pores, and spores that are typically greater than 10 μm long. It features a dimitic  hyphal system with clamped generative hyphae and dextrinoid skeletal hyphae. Characters that can be absent or present in the hymenium include small rhomboid or bipyramidic crystals, dendrohyphidia, hyphal pegs, and cystidioles or cystidia. "Megasporoporia" mainly occurs on angiosperm branches, causing a white rot. Species. "Megasporoporia setulosa" has a pantropical distribution, while the other three species are found in China. Several species once placed in "Megasporoporia" have since been transferred to other genera: