Retiboletus atrofuscus (Boletaceae, Boletales), a new species from China

Based on morphological and phylogenetic analyses, an ectomycorrhizal fungus collected from Jiangxi, China, is described as a new species. R. atrofuscus is morphological characterized by a dark gray to black pileus, white to pale yellowish white hymenophore, a grayish brown to pale yellow context, which turning orange-yellow to rusty yellow when injured, a prominently and coarsely white to pale yellow to black reticulation on upper 3/4 or entire stipe, grayish yellow to pale yellow to yellowish brown basidiospores in KOH with measuring (7-)7.5-13(-13.5) x (3-)3.5-5(-5.5) mu m. Phylogenetic analysis results showed that R. atrofuscus formed an independent lineage within Retiboletus. Descriptions and hand drawings of the new species and comparisons with similar species are presented.

Automated summary

Based on morphological and phylogenetic analyses, a new species of ectomycorrhizal fungus collected from Jiangxi, China, has been described as R. atrofuscus. The fungus is characterized by its distinct morphology, including coloration of the pileus, hymenophore, context, stipe, and basidiospores. Phylogenetic analysis revealed that R. atrofuscus forms a separate lineage within the genus Retiboletus.