Four new wood-inhabiting fungi were found in Southwestern China within the genera Phanerochaete, Phlebiopsis, Asterostroma, and Vararia of the families Phanerochaetaceae and Peniophoraceae, belonging to the orders Polyporales and Russulales individually. Combined with their morphological characteristics and molecular biological evidence, the present study describes them as new fungal taxa. Asterostroma yunnanense is characterized by the resupinate, membranaceous to pellicular basidiomata with a cream to salmon-buff hymenial surface, hyphal system dimitic bearing simple-septa, thin- to thick-walled, yellowish brown asterosetae with acute tips, and thin-walled, echinulate, amyloid, globose basidiospores. Phanerochaete tongbiguanensis is characterized by the resupinate basidiomata with a white to cream hymenial surface, a monomitic hyphal system with simple-septa generative hyphae, the presence of subclavate cystidia covered with a lot of crystals, and oblong ellipsoid basidiospores (6-9 × 3-4.5 µm). Phlebiopsis fissurata is characterized by the membranaceous, tuberculate basidiomata with a buff to slightly brown hymenial surface, a monomitic hyphal system with simple-septa, conical cystidia, and broadly ellipsoid. Vararia yingjiangensis is characterized by a corky basidiomata with a pinkish buff to cinnamon-buff hymenial surface, cracking, yellowish dichohyphae with slightly curved tips, subulate gloeocystidia, and thick-walled, ellipsoid basidiospores (6.5-11.5 × 5-7 µm). The phylogenetic analyses of ITS + nLSU revealed that the two new species were nested into the genera Phanerochaete and Phlebiopsis within the family Phanerochaetaceae (Polyporales), in which Phanerochaete tongbiguanensis was sister to P. daliensis; Phlebiopsis fissurata was grouped with P. lamprocystidiata. Two new species were clustered into the genera Asterostroma and Vararia within the family Peniophoraceae (Russulales), in which Asterostroma yunnanense was sister to A. cervicolor; Vararia yingjiangensis formed a single branch.
Keywords: Asia; Yunnan province; macrofungi; molecular systematics; taxonomy.