A new systematic arrangement of the genus Oudemansiella s. str. (Physalacriaceae, Agari-cales)
狭义小奥德蘑属（膨瑚菌科,蘑菇目）的一个新系统

The genus Oudemansiella s. str. has been revised and circumscribed as an assemblage of taxa excluding the genus Xerula s. str. A new systematic arrangement with four sections, i.e., Oudemansiella, Mucidula, Dactylosporina and Radicatae, is proposed. Section Oudemansiella is comprised of tropical to south temperate species, e.g., O. platensis, O. australis, O. canarii and O. crassifolia, with an ixotrichoderm pileipellis composed of filamentous hyphae that, in many cases, are intermixed with inflated cells often occurring in chains, while section Mucidula encompasses north temperate and subtropical taxa such as O. mucida, O. venosolamellata and O. submucida that have an ixohymeniderm-trichoderm pileipellis composed of more or less clavate terminal cells. Sections Oudemansiella and Mucidula share similar habitats and forms of basidiomata, i.e., with or without a (rudimentary) annulus on the stipe and growing on exposed rotten wood. Section Dactylosporina accommodates species from South and Central America with basidiospores that have finger-like ornamentation. Section Radicatae, represented by O. radicata and its allies, is the largest section and includes the remaining species of the genus in its restricted sense. Oudemansiella americana, O. caussei and O. hongoi, previously treated in O. sect. Albotomentosae or Xerula sect. Hyalosetae, are excluded from Oudemansiella in this treatment because preliminary data indicate that they represent a segregate genus. Section Mucidula, 32 combinations and 1 name are newly proposed.