Hymenochaete liliae (Agaricomycetes, Fungi), a new species from the state of Oaxaca, Mexico

Background and Aims: Hymenochaete is the genus with the highest number of species of the family Hymenochaetaceae in Mexico; 25 species have been described. It is characterized by its mainly resupinate basidiome, although it may be pileate and stipitate, of brown colors, with presence of setae and xanthocroid reaction. The objective of this study is to describe a new species of Hymenochaete. Methods: The fresh material was studied and described macro and micromorphologically, using a stereoscopic and optical microscope, taking photos in situ. Vouchers of the herbaria ENCB y FCME were studied, and specialized literature was reviewed for its description. Key results: Hymenochaete liliae sp. nov. is characterized by a resupinate, adnate, fleshy basidiome, smooth hymenophore, with numerous setae, determinate margin, abrupt, with monomitic hyphal system, simple septae; abundant subfusiform setae in the hymenium, 69-80 x 6-8 µm, acute, with crystals; and ellipsoid basidiospores, thin-walled, 5-8 x 2-3 µm. Although it resembles H. rhabarbarina, it can be differentiated by setae covered with crystals and spores of 4.8-6 x 2.3-3.3 µm. It could also be confused with H. minuscula due to its basidiome color; however, the setae are smaller (40-60 µm), as well as the basidia (15-20 µm). It can be separated from H. cinnamomea because it does not present a stratose basidiome; setae with crystals, 69-80 x 6-8 µm; basidiospores 5-8 x 2-3 µm, ellipsoidal. Conclusions: Hymenochaete liliae is proposed as a new species, which is distributed in the tropical dry forest of the state of Oaxaca, and until now only reported from the type locality.