Xerocomus

Xerocomus is a genus of poroid fungi (boletes) within the Boletaceae family. The genus has undergone significant taxonomic revision, with many species formerly classified under Xerocomus being reclassified into other genera such as Hortiboletus, Imleria, Rheubarbariboletus, and Xerocomellus.

Historically, Xerocomus was used as a "wastebasket" genus for boletes that possessed a dry, often cracked, or velvety cap surface, lacked a reticulated stipe, and had tubes that were typically adnate or depressed. This broad definition led to a heterogeneous grouping of species.

Following modern phylogenetic studies, based largely on DNA sequencing, Xerocomus in its current, more restricted sense includes fewer species than previously recognized. Members of Xerocomus are typically mycorrhizal, forming symbiotic relationships with trees. Fruiting bodies are often found in woodlands.

Distinguishing features of the redefined Xerocomus may include a dry, often cracked cap, a stipe lacking a distinct reticulum (though it may have granules or scales), and tubes that stain blue when bruised. Spore morphology and microscopic features are also important for accurate identification.

Due to the dynamic nature of fungal taxonomy, ongoing research may result in further revisions to the classification of species within Xerocomus and related genera. It is essential to consult up-to-date taxonomic resources for the most accurate information on bolete identification.